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COYOTE (Canis latrans) SPATIAL ECOLOGY AND INTERACTION WITH CATTLE (Bos taurus) IN THE SUB-TROPICAL RANGELANDS OF FLORIDA By KE ZHANG A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2017

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  • COYOTE (Canis latrans) SPATIAL ECOLOGY AND INTERACTION WITH CATTLE (Bos

    taurus) IN THE SUB-TROPICAL RANGELANDS OF FLORIDA

    By

    KE ZHANG

    A THESIS PRESENTED TO THE GRADUATE SCHOOL

    OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT

    OF THE REQUIREMENTS FOR THE DEGREE OF

    MASTER OF SCIENCE

    UNIVERSITY OF FLORIDA

    2017

  • © 2017 Ke Zhang

  • 3

    ACKNOWLEDGMENTS

    I would like to thank Dr. Stewart Breck and Dr. Michael Avery and the United States

    Department of Agriculture, National Wildlife Research Center for providing funding to

    undertake this study (#15-7449-1154-CA). A special thank you goes to Ralph Pfister of Adam’s

    Ranch for his skill and guidance in how to trap coyotes efficiently, as well as Cary Lightsey,

    Layne Lightsey, Jim Strickland, and Gene Lollis for allowing the work to occur on properties

    within their cattle operations. I thank the MacArthur Agroecology Research Center of Archbold

    Biological Station for logistical and data support. Thank you to Dr. Breck, Dr. Avery, Bethany

    Wight, James McWhorter, Connor Crank, and Wes Anderson for their help capturing, sampling,

    and tracking coyotes. I am very grateful to Connor Crank, Audrey Wilson, and Jane Anderson in

    supporting me as I continued to learn English during my thesis writing process. I also thank my

    committee members, Dr. Main and Dr. Basille, for their guidance during my proposal, and thesis

    writing process. Above all, I am very grateful to Dr. Boughton for his patient guidance and

    generous funding. This study was performed under IACUC #201408477 reviewed by the

    University of Florida.

  • 4

    TABLE OF CONTENTS

    page

    ACKNOWLEDGMENTS ...............................................................................................................3

    LIST OF TABLES ...........................................................................................................................6

    LIST OF FIGURES .........................................................................................................................8

    ABSTRACT ...................................................................................................................................10

    CHAPTER

    1 COYOTE HOME RANGE, MOVEMENT, AND ACTIVITY PATTERNS ..........................12

    Introduction .............................................................................................................................12 Methods ..................................................................................................................................16

    Study Sites .......................................................................................................................16 Capture, Restraint and Handling .....................................................................................17 Mortality Monitoring and Radio-telemetry .....................................................................18

    Analysis Methods ............................................................................................................19

    Results.....................................................................................................................................22 Capture and Retrieval ......................................................................................................22 Overall and Seasonal Home Ranges ................................................................................23

    Movement Rates and Circadian Rhythm .........................................................................25 Effects of Temperature and Rainfall on Coyote Activity ................................................25

    Coyote Interactions ..........................................................................................................26 Discussion ...............................................................................................................................28

    Sizes of Sub-Tropical Coyotes ........................................................................................28

    Home Range Sizes of Sub-Tropical Coyotes ..................................................................30 Movement Rates and Circadian Rhythm .........................................................................32

    Effects of Temperature and Rainfall on Coyote Activity ................................................35

    Individual Interactions .....................................................................................................36

    2 COYOTE HABITAT SELECTION, INTERACTION WITH CATTLE ................................68

    Introduction .............................................................................................................................68 Methods ..................................................................................................................................70

    Land Cover Map Preparation ..........................................................................................70

    Habitat Selection Analysis ..............................................................................................70 Cattle Movement Record .................................................................................................72

    Coyote Habitat Selection of Pasture with Cattle/Calves .................................................73 Compare Calves Carcass Records with Coyotes Movements .........................................74

    Results.....................................................................................................................................74 Simplified Land Cover Map ............................................................................................74

  • 5

    Overall Habitat Selection Result .....................................................................................74 Habitat Selection by Gender and Territoriality ...............................................................75 Cattle/Calves Pasture Selection Ratios ............................................................................75 Comparison of Calf Carcass Records with Coyotes Movements ....................................76

    Discussion ...............................................................................................................................76 Coyote Habitat Selection .................................................................................................76 Cattle/Calves Pasture Selection Ratios, Carcass Visiting Behavior ................................78

    3 CONCLUSION.......................................................................................................................101

    LIST OF REFERENCES .............................................................................................................103

    BIOGRAPHICAL SKETCH .......................................................................................................110

  • 6

    LIST OF TABLES

    Table page

    1-1 Coyote home range sizes in different studies ........................................................................38

    1-2 Coyote capture records ..........................................................................................................40

    1-3 Coyote overall home range summary ....................................................................................41

    1-4 Coyote seasonal home range summary .................................................................................42

    1-5 Coyote home range season, gender Mann-Whitney U test ...................................................43

    1-6 Coyote core use area season, gender Mann-Whitney U test .................................................43

    1-7 Hourly movement rate, time period of the day and season Linear Mixed-Effects Model

    analysis ...............................................................................................................................43

    1-8 Cumulative travel distance, time period of the day and season Linear Mixed-Effects

    Model analysis ...................................................................................................................43

    1-9 Hourly movement rate, time period of the day and season Tukey Honest Significant

    Difference analysis.............................................................................................................44

    1-10 Cumulative travel distance, time period of the day and season Tukey Honest

    Significant Difference analysis ..........................................................................................45

    1-11 Daily mean temperature and rainfall interactive effect on daily cumulative travel

    distance Linear Mixed-Effect Model analysis ...................................................................46

    1-12 Daily mean temperature and rainfall main effects on daily cumulative travel distance

    Linear Mixed-Effect Model analysis .................................................................................46

    1-13 Daily mean temperature, rainfall, and season interactive effect on daily cumulative

    travel distance Linear Mixed-Effect Model analysis .........................................................46

    1-14 Records of interactions of coyotes from two different home ranges ..................................46

  • 7

    2-1 Summary of reclassified land cover process .........................................................................82

    2-2 Grazing records example from Bucks Island Ranch .............................................................84

    2-3 Calculation selection ratio of pastures with cattle ................................................................85

    2-4 Calculation selection ratio of pastures with cattle and calves ..............................................86

    2-5 First-order level selection ratio Chi-Square Test ..................................................................87

    2-6 First-order level selection ratio Chi-Square Test in winter ..................................................87

    2-7 First-order level selection ratio Chi-Square Test in spring ...................................................87

    2-8 Second-order level selection ratio Chi-Square Test .............................................................87

    2-9 Second-order level selection ratio Chi-Square Test by territoriality ....................................87

    2-10 Selection ratios of pasture with and without cattle..............................................................88

    2-11 Selection ratios of pasture with and without cows calving .................................................88

    2-12 Chi-Square Test of cattle/calve pasture selection ratio .......................................................88

    2-13 Visits of coyote to pastures with incidental calf carcasses found by ranchers on Buck

    Island Ranch.......................................................................................................................89

  • 8

    LIST OF FIGURES

    Figure page

    1-1 Research sites ........................................................................................................................47

    1-2 Buck Island coyote home ranges ...........................................................................................48

    1-3 Lightsey coyote home ranges ................................................................................................49

    1-4 Blackbeard coyote home ranges ............................................................................................50

    1-5 Circadian activity of coyote hourly movement in winter and spring ....................................51

    1-6 Coyote hourly movement rates in different seasons and time periods ..................................52

    1-7 Coyote hourly movement rates in different seasons and time periods Tukey Honest

    Significant Difference ........................................................................................................53

    1-8 Coyote cumulative travel distance in different seasons and time periods .............................54

    1-9 Coyote cumulative travel distance in different seasons and time periods Tukey Honest

    Significant Difference ........................................................................................................55

    1-10 Predicted temperature and rainfall effect on daily travel distance ......................................56

    1-11 Coyote daily travel distance by temperature and season .....................................................57

    1-12 Instantaneous distance between female juvenile coyote F2 and F3 every 30mins .............58

    1-13 Coyote F3 travel out of the home range on 3/13/2015 ........................................................59

    1-14 Coyote F3 & M1 interaction on 3/10/2015 .........................................................................60

    1-15 Coyote F2 travel out of the home range on 4/18/2015 ........................................................61

    1-16 Instantaneous distance between female juvenile coyote F9 and F10 every 30mins ...........62

    1-17 Coyote F8 & F9 & F10 interaction on 12/22/2014 .............................................................63

    1-18 Coyote M13 & M15 interaction on 12/15/2014 ..................................................................64

    1-19 Coyote M13 & M15 interaction on 4/5/2015 ......................................................................65

    1-20 Coyote home ranges in southern states ...............................................................................66

    1-21 Resident coyote home ranges in winter and spring season of Florida ................................67

  • 9

    2-1 Home range of two male coyotes and two female coyotes on the Buck Island Ranch

    showing underlying simplified land cover categories .......................................................90

    2-2 Home ranges of one male coyote and two female coyotes on the BlackBeard Ranch

    showing underlying simplified land cover categories .......................................................91

    2-3 Home ranges of two male coyotes on the Lightsey Ranch showing underlying

    simplified land cover categories ........................................................................................92

    2-4 First-order level resource availability and utilization proportions ........................................93

    2-5 First-order level habitat selection ratios for whole study period ...........................................94

    2-6 First-order level habitat selection ratios in winter .................................................................95

    2-7 First-order level habitat selection ratios in spring .................................................................96

    2-8 Second-order level habitat selection ratios by gender and season ........................................97

    2-9 Second-order level habitat selection ratios by territoriality and season ................................98

    2-10 Buck Island Ranch pasture boundary, carcass reported pastures, coyote home ranges

    map .....................................................................................................................................99

    2-11 Buck Island Ranch pasture boundary, carcass reported pasture, coyote home ranges,

    and coyote location points on 11/12/2014 .......................................................................100

  • 10

    Abstract of Thesis Presented to the Graduate School

    of the University of Florida in Partial Fulfillment of the

    Requirements for the Degree of Master of Science

    COYOTE (Canis latrans) SPATIAL ECOLOGY AND INTERACTION WITH CATTLE (Bos

    taurus) IN THE SUB-TROPICAL RANGELANDS OF FLORIDA

    By

    Ke Zhang

    May 2017

    Chair: Raoul Boughton

    Major: Wildlife Ecology and Conservation

    Coyote are medium sized predatory, native American Canidae, that during the last one

    hundred years has expanded its range extensively to include much of the North American

    continent, including Florida. By the year 2000, coyote presence had been confirmed in all

    counties of Florida (McCown & Scheick, 2007). The sub-tropical climate and intense cattle

    husbandry in south-central Florida provide excellent environmental conditions for coyote to

    survive, leading to changes in biological responses, such as increased phenotypic size and shifted

    spatial behaviors. From November 2014 to May 2015, I retrieved extensive locational data from

    9 coyotes spread over three research sites (Buck Island Ranch, BlackBeard Ranch, and Lightsey

    Ranch). Using these spatial locations, I 1) tested for effects of season and gender on coyote home

    range, 2) describe coyote circadian activity pattern and test for relationships between temperature

    and rainfall with coyote movement, 3) infer interactions among coyote dyads using proximity

    and describe the patterns of these occurrences, and 4) examined habitat selection of coyote

    within rangelands of Florida, to understand if coyote have a preference for improved pasture

    habitats, and if preference increases when pastures are stocked with cattle or cattle are calving.

  • 11

    The average resident home range size of coyotes in my study area was 27.14 km2. Floridian

    coyotes were most active during crepuscular and nocturnal periods of the day. In the spring,

    coyote became more active, having higher hourly movements and longer cumulative travel

    distance than in the winter. Increasing temperature and rainfall negatively correlated with daily

    travel distance. Resident adult male coyotes in adjacent territories avoided encountering each

    other during the period of the study, transient males infrequently encountered resident males. In

    two cases females from the same group interacted frequently and are thought in one case to be

    siblings and the other possibly a mother and daughter. At the population level, coyote preferred

    improved pasture, forest, and scrub & shrub habitats. Where as they spent less time in wetland

    areas, roads, open water, human communities and dry prairie. There was no evidence that coyote

    preferred pastures with cattle or calves to any greater extent than the pastures without. Taken

    together, coyote prefer improved pastures and although do occasionally take calves, their activity

    patterns suggest there are many other factors that may drive their use of pasture other than the

    presence of cattle and calves.

  • 12

    CHAPTER 1

    COYOTE HOME RANGE, MOVEMENT, AND ACTIVITY PATTERNS

    Introduction

    Coyotes originated in western North America, but are now commonly found throughout

    the continent of North America. By the 1960s, coyotes had crossed the Mississippi river into the

    southeastern United States (McCown & Scheick, 2007), entering northern Florida from Alabama

    and Georgia. Populations were established in the panhandle and northern region of Florida by the

    1970s (Layne, 1994), and the establishment of coyote populations in Florida was contributed to

    by both natural expansion and release of coyotes used for hound hunts (Hill et al., 1987). A

    survey conducted in 1983 documented coyotes in 18 Florida counties, primarily in the panhandle

    (Brady & Campbell, 1983). The presence of coyote populations was confirmed in central Florida

    in 1990 (Wooding & Hardisky, 1990). By the middle of 1990s coyotes were well established in

    southern Florida (Maehr et al., 1996), and by 2000, coyotes were confirmed in 65 of Florida’s 67

    counties (Main et al., 2000). Today, coyotes inhabit all counties of Florida (McCown & Scheick,

    2007).

    Coyotes can be described as resident or transient based on the spatial behavior patterns of

    individuals. Residential coyotes are territorial, show aggressive behaviors toward intruders,

    maintain consistent home range boundaries which manifest in consistent and repeated use of

    specific areas over time, and usually have a smaller home range in general, while transients are

    the alternative. Transients generally have large and disjointed home ranges, showing no fidelity

    to any given area (Hinton et al., 2015). Transients may be coyotes that are unable to find a mate

    and defend a territory. The delineation between resident and transient coyotes needs to be taken

    into account when attempting to understand home range sizes and activity patterns of coyotes.

  • 13

    Coyotes show large variation in home range sizes across North America (Table 1-1).

    Coyote home ranges have also been shown to vary by age, gender, season, territoriality, and land

    cover types (Hotzman et al., 1992; Hinton et al., 2015; Gese et al., 1998; Laundre & Keller,

    1984; Gese et al., 1990). One study of particular focus in Florida includes analyses of coyote

    home ranges and activity patterns in an area dominated by natural communities with only about

    3% pasture. Within these natural communities of Florida, annual coyote home range sizes

    averaged 24.8 km2 (95% Confidence interval = 16.96 – 32.64 km2, n = 7, 95% fixed Kernel) and

    did not differ between dry and wet seasons (Thornton et al., 2004). Coyotes preferred scrub

    habitat within core home ranges (50% fixed Kernel) with the highest selection ratios among 8

    land cover types in both the dry and wet seasons, but preference to scrub was only significant in

    the wet season. The preference to scrub habitat could be explained by potential prey base and

    high rodent densities in this type of environment (Franz et al., 1998). Coyotes avoided wet

    habitats such as swamp and marsh within core home ranges, especially during the wet season

    (Thornton et al., 2004).

    Coyote are more active during crepuscular and nocturnal hours and are relatively inactive

    during diurnal hours. Although coyote are active during crepuscular hours, the peak of activity

    can be either dawn or dusk depending on seasonality, breeding condition, and anthropogenic

    patterns of activity and influences (Arias-Del Razo et al., 2010; Andelt & Gipson, 1979; Way et

    al., 2004). In Florida, coyote display a circadian rhythm of movement rates with nocturnal and

    crepuscular periods higher than diurnal periods (Thornton et al., 2004). Sun exposure and severe

    heat in the sub-tropical environment may be the factors that drive coyotes to avoid diurnal

    activities. However, research on the relationship between day length, temperature, and coyote

    activity in the sub-tropical environment like Florida is scarce.

  • 14

    Coyotes are omnivores, exhibiting broad diet capabilities and complicated interactions

    with local food resources which, in turn, define activity and spatial use. For example, coyotes

    prey on small mammals, reptiles, birds, insects, and larger species such as white-tailed deer

    (Odocoileus virginianus) (Stout, 1982), mule deer (Odocoileus hemionus) (Truett, 1979), elk

    (Cervus canadensis) (Robinson, 1952), and moose (Alces alces) (Benson & Patterson, 2013).

    The distribution, seasonal availability, and density of these prey items are likely to influence

    coyote behaviors, activity patterns, and spatial use (Bekoff & Wells, 1986). One particular study

    from the Great Basin of northern Utah and southern Idaho, where jackrabbit (Lepus californicus)

    is the major prey of coyote, indicated that coyote home ranges can be significantly larger when

    prey is scarce compared to when prey is abundant, and there is a higher chance of increased

    proportion of transients when food is lacking (Mills & Knowlton, 1991). In the western coastal

    area of Florida, insects and berries were found most frequently in coyote fecal samples in a

    wildland reserve area during the wet season, while rabbits, rodents, and deer were found most

    frequently during the dry season. (Grigione et al., 2011). Similarly, in Avon Park located in

    central south Florida coyote fecal samples contained vegetation material, white-tailed deer, feral

    swine (Sus scrofa), cattle, rodents, and rabbits. There was 5% occurrence of cattle found across

    samples, even though 97% of habitat coyotes used was native (Thornton et al., 2004). In 2014,

    there were 1.7 million head of cattle and calves in Florida, with Okeechobee, Highlands,

    Osceola, Polk, and Hardee counties being the top five producers, all of which distributed in

    central south Florida (Florida Department of Agriculture and Consumer Services, 2014). The

    large cattle and calves industry in these regions may provide abundant food resources through

    modification of native habitats to improved pasture and a possible increase in biomass of prey,

  • 15

    reducing the necessity of larger movements and home ranges for coyotes to access food

    resources.

    Coyote range expansion has also led to increased interactions with other predators. For

    example, coyotes may compete with lynx (Lynx canadensis) for highly important prey items

    such as the snowshoe hare (Lepus americanus) (Kolbe et al., 2007). Coyote are highly

    competitive with other species of similar size, and have been show to kill bobcats (Felis rufus)

    (Gipson & Kamler, 2002), and rarely, lynx (O’Donoghue et al., 1997). From the measurement of

    food habit overlap among carnivores in south Florida, there was a speculation that coyote were

    more competitive with bobcats, black bears (Ursus americanus), and Florida panthers (Puma

    concolor coryi) than local carnivores competed with each other (Maehr, 1996). A study of the

    interactions between coyotes and bobcats in south-central Florida suggested that coyotes and

    bobcats display similar habitat selection, activity patterns, and overlapping home ranges.

    Segregation may occur between the two species at finer scales of core use areas (50% Fixed

    Kernel), suggesting a level of territoriality and competition (Thornton et al., 2004), this may

    reduce availability of resources to bobcat. Other effects caused by competition between coyotes

    and other predators need to be further investigated but are beyond the scope of this study.

    Studies of coyote ecology in Florida have addressed population expansion, home range,

    habitat selection, diets, and parasites (Maehr et al., 1996; Thornton et al., 2004; Grigione et al.,

    2001; Foster et al., 2003). Since the home range, activity pattern, and habitat selection analysis of

    coyote in Florida have only been carried out in a natural environment (Thornton et al., 2004), it

    is largely unknown how the dominant land use in south central Florida, cattle ranching, has

    impacted the behavioral ecology of coyote. The altered land cover and abundant distribution of

    cattle may have a variety of potential effects on coyotes. To understand how coyotes may behave

  • 16

    differently in this agricultural landscape, I undertook a study to describe home ranges, movement

    rates, activity patterns, and spatial interactions among coyotes captured on ranches in south

    central Florida. The hypotheses are 1) coyote have different home range sizes and circadian

    activity patterns in different seasons of the year, 2) the temperature and rainfall have effect on

    coyote daily cumulative travel distance, 3) there are frequent interaction among coyotes from the

    same group. I specifically examined home range size across gender, age, season, and

    territoriality; describe movement activity across time of day and test if there is a seasonal (winter

    versus spring) effect upon circadian activity; investigate temperature and rainfall influence upon

    movement behavior; and described interactions among coyotes when they occurred.

    Methods

    Study Sites

    Coyotes were trapped in November and December 2014 on three different ranches

    located in south central Florida (Figure 1-1). The ranches were located approximately 50 km

    apart. The Lightsey Ranch is located 10 km east of the city of Lake Wales, south of Tiger Lake

    (27°51’, -81°22’). The Buck Island Ranch is located 6 km east of the city of Lake Placid (27°09’,

    -81°06’). The BlackBeard’s Ranch is north of Myakka River State Park (27°16’, -82°08’). The

    density of human residents living within each site was very low (< 8%) except around the

    Blackbeard’s Ranch. The human densities were slightly higher (10%) at the Blackbeard’s Ranch

    site because the low-density residential areas occurred in the north and west sides of the ranch.

    All research areas had similar topography and habitat types typical of south central Florida.

    These habitats consisted of palmetto palm prairies, shrublands, open pine flatwoods, hammock

    forest, improved pasture, and marsh wetlands. The climate of the area is subtropical, with a

    winter season from November 2014 through March 2015 (Daily mean temperature range: 6.65 ~

  • 17

    26.4 °C) and spring season from March 2015 through May 2015 (Daily mean temperature range:

    13.9 ~ 29.72 °C). Annual rainfall averaged 132 cm, of which 75% typically falls during the wet

    season in the summer (Swain et al., 2007).

    Capture, Restraint and Handling

    At each study site, I searched for signs of coyote presence (i.e., footprints, scats, scrapes

    and dens). Once potential areas of coyote activity were found, I set a trapping array of 1-4 soft

    catch foothold traps (MB-550- Rubber Jaw 4 coil). These soft catch foot-hold traps had rubber

    pads applied to the jaws to minimize foot injury. Each trap was dyed and waxed before

    deployment to minimize human scent and maintain trap condition. I attached a trap tranquilizer

    device (TTD) to each foothold. The TTD is a chewable pouch containing a tranquilizer, in this

    case 600 mg propiopromazine hydrochloride (Sahr & Knowlton, 2000; Zemlicka et al., 1997), to

    induce lethargy in the coyote and reduce injury when trying to escape from the trap. I used a

    variety of scent lures including skunk scent, coyote urine, deer meat and fermented horse flesh

    mingled with a sight lure such as a cow bone to attract coyotes to the traps. I set up traps during

    the evening and checked traps regularly to avoid any coyotes suffering from heat or dehydration.

    If a coyote was captured, I used a Y pole at the neck to pin the coyote to the ground. The

    animal was then restrained by hobbling three feet, muzzling and applying a hood. The coyote

    was then carefully removed from the foothold and processed in a shielded area on a cover sheet.

    During the capture I monitored temperature and recorded morphometrics (length, weight, teeth

    eruption and wear), gender, reproductive status, estimated age, and then collected samples for

    other studies including blood, hair and scat. Body length (cm) and weight (kg) were reported as

    mean, median, and 95% Confidence interval (95% CI). Mann-Whitney U test (Ruxton, 2006)

    was used to evaluate the difference on body length and weight between genders. Refurbished

  • 18

    GPS LOTEK 3300 store-on-board collars with timed release drop-off mechanisms (set to 6

    months) were fitted to each coyote. The GPS was set to record location every 30 minutes from

    16:00 to 10:00 and hourly between 10:00 to 16:00 to conserve battery when coyotes are

    suspected to move the least. The collars were recovered using collar specific Very High

    Frequency (VHF) transmitters set to transmit continuously. I set collar mortality functions to go

    off after 4 hours of stationary activity, at which point the pattern of VHF signal increased in bip

    rate to signify stationary behavior of the collar (e.g., slipped, or dropped from animal, or animal

    deceased).

    Coyotes were released and their condition was observed until their revival from the effect

    of tranquilizer, after which they were able to walk away on their own accord. I returned to the

    release location after one hour to confirm that the coyote had left and was mobile using a VHF

    radio receiver (Communication specialists model # R1000) with a Yagi antenna (Lotek centered

    on 165mhz).

    Mortality Monitoring and Radio-telemetry

    I tracked coyotes weekly to check for mortality events and roughly recorded coyote

    locations using triangulation, to make sure they had not left the general area. Drop-off

    mechanisms were designed to go off six months after the deployment date, at which time I

    located and retrieved the collars. For coyotes that exited the study area and were no longer

    trackable via ground VHF antenna, I attempted to locate the deployed collars using aerial

    surveys. Two flights were undertaken near the end of the 6 months on each property in either a

    Cessna 150 or Cubcrafters Carbon Cub EX. A survey of 50 km2 radius was performed. All collar

    data were then downloaded to a computer using the LOTEK interface (Download-link version 1)

    and the software GPS host 3300. Data were cleaned before analyses with relocation points of

  • 19

    greater probability of low accuracy (hdop > 7.5) removed and relocations truncated to from

    deployment date to date when collars were dropped or slipped from coyotes.

    Analysis Methods

    Estimation of Home Range

    I defined November 2014 to the end of February 2015 as winter season, then beginning

    of March 2015 to June 2015 as spring season. I estimated overall and seasonal home range areas

    for each coyote using two methods: Minimum Convex Polygon (MCP) and fixed Kernel

    Utilization Distribution (KUD). In both cases a 95% cut-off was used; in MCP the smallest area

    containing 95% of fixes and in the KUD the 95% of kernels with highest probability of use,

    converted to polygon areas. I also estimated core areas using 50% MCP and 50% KUD.

    For the Kernel Utilization Distribution model, I used bivariate normal kernel, with

    parameter h estimated by “reference bandwidth” that is equal to:

    ℎ = 𝜎×𝑛16

    when

    𝜎 = 0.5×(𝜎𝑥 + 𝜎𝑦)

    The 𝜎𝑥 and 𝜎𝑦 are the standard deviations of the horizontal and vertical coordinate of

    the location points, n is the amount of the location points.

    The analyses were performed in the adehabitatHR package (Calenge, 2006) using

    Rstudio (version 0.99.893, Rstudio team, 2015). I reported the results of both, but only used

    polygons derived from the fixed KUD method to undertake statistical analyses because it is more

    specific and accurate in identifying actual likely use of a specific area compared with MCP

    (Worton, 1989). The home range sizes were reported as mean, median, and 95% CI by groups. I

    used Mann-Whitney U test (Ruxton, 2006) to evaluate the difference in the sizes of home ranges

  • 20

    between genders, ages, resident and transient, and in different seasons. I plotted the result of

    home range analysis with average value and standard error, compared my findings with other

    known home range.

    Hourly Movement Rate and Circadian Activity

    I used the adehabitatLT package in R (Calenge, 2006) to calculate the hourly movement

    rate. I extracted the points recorded on the hour from the original data. The hourly movement

    rate was defined by the distance between two consecutive location points, that should result in 24

    hourly distance records. However, because of non-fixes or location points removed with low

    accuracy, there were 3% of points absent, these points and the points next to them were not used

    to calculate the hourly speed of movement. I calculated mean hourly movement rates of each

    coyote, and then combined all coyotes together to estimate average hourly movement rates of the

    population and plotted by hour to show circadian activity trends.

    I obtained daily sunrise and sunset times of the research period from Astronomical

    Application Department U.S website (http://aa.usno.navy.mil/). I divided 24 hours into four time

    periods of the day: dawn (sunrise time ± one hour), dusk (sunset time ± one hour), diurnal

    (sunrise time + one hour to sunset time – one hour), and nocturnal (the rest of hours). I calculated

    the cumulative travel distance in each time period as the sum of all hourly movement rates in the

    time period. Due to the change in day length, I defined November 2014 to the end of February

    2015 as the winter short daily photoperiod, then beginning of March 2015 to June 2015 as spring

    long daily photoperiod. I used boxplot to present the hourly movement rate and cumulative

    distance travelled within each time period in winter and spring season separately.

    All the hourly movement rates and cumulative travel distances were square-root

    transformed before the statistical tests. I used Linear Mixed-Effects Model to test if hourly

  • 21

    movement rate and cumulative travel distance are effected by time of the day and season. I used

    Tukey’s Honest Significant Difference (Yandell, 1997) after the Linear Mixed-Effects Model to

    test the interactive effects among time period of the day and the season. Random effects from

    coyote individuals and location sites were blocked in the analysis. Linear Mixed-Effects Model

    analysis was carried out by nlme package in R (Pinheiro et al., 2017). Tukey’s Honest

    Significant Difference analysis was carried out by multcomp package in R (Hothorn et al., 2008).

    Effects of Temperature and Rainfall on Coyote Activity

    To understand how weather and local climatic variables may influence coyote activity, I

    obtained daily mean temperature and rainfall data from Florida State Weather Center website

    using the closest weather station to each research site. The stations were Archbold Biological

    Station (27.16670, -81.35000), 14 km away from the Buck Island site, MTN lake Station

    (27.93330, -81.58330), 23 km away from the Lightsey site, and Myakka River SP Station

    (27.23330, -82.30000), 5 km away from the Blackbeard’s Ranch site. I calculated daily

    cumulative travel distance as the sum of the distances coyote moved in each hour of the day. All

    the cumulative travel distances were square-root transformed, the rainfall record was converted

    to the category of rain and no rain based on daily rainfall. I used Linear Mixed-Effects Model to

    investigate the relationship between daily cumulative travel distance, temperature, presence of

    rainfall, and the seasons. Random effects from coyote individuals and location sites were

    blocked in the analysis. Linear Mixed-Effects Model analysis was carried out by nlme package

    in R (Pinheiro et al., 2017).

    Spatial Interactions

    I described the spatial interactions of coyotes by calculating the overlapping area between

    their home ranges, estimating instantaneous distance, and recording occasional visit behavior

  • 22

    into other coyote’s home ranges. I used the result from home range analysis to calculate the

    overlapping areas between coyote home ranges. Pythagorean theorem was used to calculate the

    instantaneous distance between every two coyotes. I plotted the instantaneous distances between

    females who sharing same home ranges, to present their long-term interaction through the

    research period. I defined the average coyote movement rate as 70 m/minute, and because there

    was a one-minute variation in recording location on GPS, I considered two coyotes with an

    instantaneous distance of < 140 m (the farthest distance two coyotes can be dispersed from each

    other in one minute) as interacting at that moment. I then plotted the location points of these

    coyotes with their home ranges on the maps to present their interactions and visiting behavior

    toward each other’s home range.

    Results

    Capture and Retrieval

    I captured and placed collars on 15 coyotes across three research sites from November

    through December 2014 (Table 1-2). No coyotes were injured during the capture and all coyote

    were left in the shade to revive after handling. All coyotes revived and left by themselves within

    one hour after the handling.

    Among the coyotes I captured, eight of them were female (two adults, eight juveniles),

    and seven of them were male (all adults). Average male body length (mean = 99.57 cm, median

    = 98.00 cm, 95% CI = 95.63 - 103.51 cm; n = 7) was similar (U = 13.5, p = 0.10) to average

    female body length (mean = 92.38 cm, median = 88 cm, 95% CI = 86.87 – 97.89 cm; n = 8).

    Average male weight (mean = 16.19 kg, median = 16.4 kg, 95% CI = 17.39 – 14.99 kg; n = 7)

    was heavier (U = 6, p = 0.0009) than average female weight (mean = 12.72 kg, median = 12.1

    kg, 95% CI = 11.39 – 14.05 kg; n = 8).

  • 23

    By the beginning of June 2015, I had successfully retrieved 11 collars from the field.

    Four remained missing and were not found by aerial surveys. Among the 11 collars I retrieved,

    three of the coyotes were killed by humans; one was hit by a vehicle on 11/16/2014 and one was

    shot on ranch on 12/23/2014. The third was shot by a rancher over 21 km from the capture

    location, but the collar still contained five months of data. Due to the short deployment period,

    the first two coyote collars killed by humans were not used in analyses. The nine remaining

    collars included 5 male adults, 1 female adult, and 3 female juveniles. Among these nine

    coyotes, average male body length (mean = 98.6 cm, median = 98 cm, 95% CI = 93.78 – 103.42

    cm; n=5) was similar (U = 6.5, p = 0.46) to average female body length (mean = 93.5 cm,

    median = 93 cm, 95% CI = 86.11 – 100.89 cm; n=4). Average male weight (mean = 16.34 kg,

    median = 16.4 kg, 95% CI = 14.95 – 17.73 kg; n=5) was similar to (U = 2, p = 0.06) that of the

    females (mean = 12.62 kg, median = 12 kg, 95% CI = 10.78 – 14.46 kg; n=4).

    Coyote location data began on 11/12/2014, the second day after the release of the first

    captured coyote, and ended on 6/6/2015, the last day before collar drop off for the last coyote.

    Although collars were all programed to drop off from coyotes after 6 months recording time,

    some collars were collected before the scheduled day because of coyote’s death or collar-

    slipping for unknown reason. The average number of location points recorded by each collar was

    6737. Coyote M1 had the most location points out of any collar (7587), and coyote F9 had the

    least location points (4667; Table 1-2).

    Overall and Seasonal Home Ranges

    Given the shape and size of their home ranges during the six-month study, I classified

    seven coyotes (three males, four females) as residents, and two coyotes (both males) as transients

    (Figure 1-2; Figure 1-3; Figure 1-4). The two male transients (M8 and M15) had large home

  • 24

    ranges of 921 km2 and 88 km2 under 95% KUD, respectively. Mean home range for all residents

    was 27.14 km2 (median = 27 km2, 95% CI = 19.00 – 35.27 km2; n = 7) under 95% KUD, and

    mean core home range (50% KUD) for all residents was 4.86 km2 (median = 4 km2, 95% CI =

    2.08 – 7.64 km2; n = 7). The home ranges were not significantly different for male residents

    (mean = 20.33 km2, median = 20 km2, 95% CI = 8.45 – 30.21 km2; n = 3) compared to female

    residents (mean = 32.25 km2, median = 31 km2, 95% CI = 23.16 – 41.34 km2; n = 4) under 95%

    KUD (U = 2, p = 0.23). Similarly, core areas were not significantly different for male residents

    (mean = 4.33 km2, median = 2 km2, 95% CI = -1.26 – 9.92 km2; n = 3) compared to female

    residents (mean = 5.25 ± 1.7 km2, median = 4.5 km2, 95% CI = 1.92 – 8.58 km2; n = 4) under

    50% KUD (U = 4, p = 0.59; Table 1-3).

    Under 95% KUD and 50% KUD, I found no significant differences in resident coyote

    home range sizes among seasons (Table 1-4; Table 1-5; Table 1-6). In the winter, female

    residents had an average home range size of 25.25 km2 (median = 25 km2, 95% CI = 16.80 -

    33.70 km2; n = 4), while male residents had an average home range size of 26 km2 (median = 32

    km2, 95% CI = 9.10 – 42.90 km2; n = 3). In the spring, female residents had an average home

    range size of 40.75 km2 (median = 38.5 km2, 95% CI = 28.17 – 53.33 km2; n = 4) under 95%

    KUD, while male residents had an average home range size of 17 km2 (median = 10 km2, 95%

    CI = 3.28 – 30.72 km2; n = 3). Among all three female juvenile coyotes, the average home range

    size increased from 22 km2 (median = 26 km2, 95% CI = 14.16 – 29.84 km2; n=3) to 42.67 km2

    (median = 42 km2, 95% CI = 25.68 – 59.66 km2; n=3) from the winter to the spring, although the

    difference is insignificant (U = 0, p = 0.08).

  • 25

    Movement Rates and Circadian Rhythm

    Average coyote hourly movement rates began to increase at dusk and were maintained

    through the night until dawn. After dawn, coyotes became inactive and traveled less during the

    diurnal period. Descriptively, from November 2014 to early March 2015, hours of maximum

    activity were 18:00-19:00, 21:00-22:00, while from early March 2015 to June 2015, hours of

    maximum activity were 19:00-20:00 and 22:00-23:00. Coyote maximum average movement rate

    in the spring was 1060 m/hour at 19:00, while the maximum average movement rate in the

    winter was 900 m/hour at 19:00 (Figure 1-5).

    Both time period of the day and season had effects on average hourly movement rate and

    cumulative travel distance, there were also interactive effects among time period of the day and

    the season (Table 1-7, Table 1-8). In both of the spring and winter, coyote had higher hourly

    movement rates at dawn, dusk, and nocturnally, compared to diurnal rates (Figure 1-6). The

    average hourly movement rates in each time period of the day in the spring were higher than the

    corresponding hourly movement rates in the winter (Table 1-9, Figure 1-7). In both the spring

    and winter, coyote traveled the longest distance during the night while distances were relatively

    low during dawn, diurnal, and dusk (Figure 1-8). The travel distance in dawn, diurnal, and dusk

    in the spring were longer than the corresponding distance in the winter, whereas the nocturnal

    travel distances were similar in winter and spring season (Table 1-10, Figure 1-9).

    Effects of Temperature and Rainfall on Coyote Activity

    During the research period (November 2014 – May 2015) daily mean temperature varied

    from 6.65 to 29.72 ℃, and daily mean rainfall varied from 0 to 6.05 cm, and averaged 0.26 cm.

    There was no interactive effect of temperature and rainfall on distance travelled (Table 1-11).

    However, both mean daily temperature and the presence of the rainfall significantly and

  • 26

    negatively impacted daily travel distance when the interaction was removed the model (Table 1-

    12). The predictive equation model based on temperature and rainfall to estimate the distance

    when there is no rain was:

    D = [t×(−0.234) + 117.34]2

    The predictive equation model to estimate the daily movement when there is rain should

    be:

    D = [t×(−0.234) + 114.38)2

    Where D is the cumulative daily movement (m/day), t is the daily mean temperature (℃),

    and it is squared to adjust back from square root distance. In this model as daily mean

    temperature increases by 5 ℃, the daily distance travelled decrease about 270m/day, and when it

    rains the daily distance travelled decreases a further 650m/day (Figure 1-10).

    There was no interactive effect of temperature, season and rainfall (Table 1-13) and the

    relationship of decreased distance travelled with increasing temperature was the same in both

    seasons but coyotes travelled less overall in winter (Figure 1-11).

    Coyote Interactions

    Male adult residents at Buck Island (M1, M5) had exclusive home ranges (Figure 1-2).

    There was a small shared area (2.5 km2) between the 95% KUD home ranges of these two male

    adult residents, which was about 12.5% of M5 home range (20 km2) and 8% of M1 home range

    (31 km2). There was no overlap between the core areas of M1 and M5.

    Male transient coyote (M15) had large 95% KUD home range (88 km2) which covered

    the home range of one male resident (Figure 1-3). Male transient coyote(M8) had huge 95%

    KUD home range (921 km2) which covered the home ranges of the two female residents (Figure

  • 27

    1-4). However, the core areas of the transients did not overlap with the core areas of any male or

    female residents that we had collared.

    I only had data from one female adult resident (F9) who shared her home range (95%

    KUD) almost completely with a juvenile (F10), except their core use areas (50% KUD) were not

    overlapped with only 1.8 km2 shared, which was 18% of adult core area and 35% of juveniles

    (Figure 1-4). In the case of two juvenile females they shared their 95% and 50% KUD almost

    completely (Figure 1-2).

    Collared coyotes presented a variety of interactions influenced by age, gender, and home

    ranges (Table 1-14). At the Buck Island site, two female juveniles (F2 & F3) interacted

    throughout the whole research period, and were likely from the same litter. From the beginning

    of February 2015, the interactions became less frequent, and the average distance between the

    two coyotes increased (Figure 1-12). From the beginning of February 2015, F3 began to

    frequently leave her home range, travel into the home range of M1. From 2/21/2015 to

    5/22/2015, there were 20 days that F3 traveled into the boundary area of M1 home range. Most

    of the travel ended up by F3 returning to her home range on the same day. During 3/13/2015-

    3/14/2015, F3 traveled cross the home range of M1 to the northeast part of the ranch, and

    returned to her own home range on 3/15/2015 (Figure 1-13). Although F3 frequently traveled

    into the home range of M1, there was only one time inferred interaction between these two

    coyotes. On 3/10/2015, the closest distance between F3 and M1 was 124 m, which happened in

    the boundary area between their home ranges around 1:30 am (Figure 1-14). Another female

    juvenile (F2) rarely left her home range. During 4/17 - 4/18/2015, F2 left her home range, and

    travelled several kilometers to the west, then to the north, and eventually entered the home range

    of the male coyote M5 (Figure 1-15). However, she went back to her home range right after this

  • 28

    travel. There was no interaction between F2 and M5; the closest distance between them was 4

    km.

    At the Blackbeard’s site, a female adult and a female juvenile (F9 & F10) interacted

    throughout the whole research period, without a shift in the frequency or average distance

    between the two coyotes (Figure 1-16). These two females both encountered transient male adult

    (M8) on 12/22/2014, female juvenile (F10) at 4:30 and female adult (F9) at 5:00. This happened

    by F9 traveled into the home ranges of F10 and F9, then dispersed and had no further

    interactions with these females (Figure 1-17).

    At the Lightsey site, transient M15 had a large home range which covered more than 85%

    of the home range of resident M13 (Figure 1-3). From 12/14-2014 to 4/12/2015, there were at

    least 30 days that M15 visited the home range of M13. However, there were only two instances

    of interactions between M15 and M13. On 12/15/2014, the interaction began at 08:00, and

    interestingly the distance maintained between these coyotes was only several hundred meters

    until 18:00 when they separated (Figure 1-18). On 4/5/2015, these two males again interacted for

    hours and the closest distance between them was 95 meters at 5:00 before they completely

    separated (Figure 1-19).

    Discussion

    Sizes of Sub-Tropical Coyotes

    In the subtropical environment of central south Florida, the average male coyote weight

    (all adults) was heavier than average female coyote weight (two adults, six juveniles). This

    suggested difference was likely because of the juvenile females. Compared to a separate study in

    central south Florida in mostly native habitat (Thornton et al., 2004) which reported male

    weights of 14.2 kg (95% CI = 13.42 – 14.98 kg, n = 3, adults) and female weights as 13.0 kg

  • 29

    (95% CI = 12.41 – 13.59 kg, n = 4, four adults, one juvenile), the adult coyotes from my research

    are approximately 2 kg heavier. This 15% greater coyote weight could be due to a number of

    reasons, such as small sample size. The coyotes in my research were captured and weighed in

    November and December of 2014, although not described exactly in Thornton et al., (2014) it is

    suspected that coyote weight data was collected during April and May before VHF telemetry was

    began. In sub-tropical Florida April and May is the end of the dry season and food resources may

    be limited compared to later in the year when I captured coyote. There is evidence for changes in

    male and female coyote weights increasing from summer to winter and decreasing from winter to

    summer, with suggested reasons that coyote have increased body weight in the winter to

    withstand cold temperature, deficiency of food, or to provide the additional energy for the

    breeding in the spring (Poulle et al., 1995). Another, more intriguing hypothesis is that the

    habitats and resources provided in the predominantly improved grazing landscape in my research

    allowed coyotes to be in better condition and grow larger.

    The body weights of coyote in Florida are heavier than in many regions of United State

    of America. The heaviest coyotes were in northeastern region, average weights of coyote were

    16.4 kg and 14.7 kg for male and female according to the summarized data from several studies

    (Way, 2007). In California, average weights of coyote were 10.9 kg and 9.8 kg for male and

    female, respectively (Hawthorne, 1971). In Texas, average weights of coyote were 12.6 kg (n =

    46) and 10.5 kg (n = 38) for male and female, respectively (Young & Jackson, 1951). According

    to Bergmann’s Rule, warm-blood vertebrates from cooler climates tend to be larger than same

    species living in warm climates. Although, the northeastern coyotes have the heaviest weights

    comparing with other regions in the United States of America, Longitude was significantly more

    correlated in body weights than latitude. 62% variation of the male weights (p < 0.0001) and

  • 30

    59% variation of the female weights (p < 0.0001) can be explained by longitude, while only 13%

    variation of the male weights (p = 0.043) and female (p = 0.044) could be explained by latitude

    (Way, 2007). The small size of Californian and Texan coyotes may be because of dry, hot arid

    climates with scarce of resources. The richer forests of the eastern US could be providing greater

    and more regularly resources for coyote allowing for increased body size in the populations. The

    larger body size of eastern coyote may also be contributed to increased hybridization with the

    timber wolf (Canis lupus) and red wolf (Canis rufus), genetic selection to adapt to bigger prey,

    and phenotypic increased in body size because of the greater food supply (Larivière & Crête,

    1993; Thurber & Peterson, 1991). Although the coyote hybridization with wolf is still undefined

    in Florida, the large population of white-tailed deer and year-round cattle industry in central

    south Florida may provide a greater amount of food for coyote resulting in heavier weight of

    coyotes in eastern US and Florida.

    Home Range Sizes of Sub-Tropical Coyotes

    The home range size of coyotes estimated under 95% fixed Kernel were relatively

    consistent with the home range size estimated under 95% MCP, however, the core areas of

    coyotes estimated under 50% fixed Kernel were not always consistent with the core areas

    estimated under 50% MCP (Table 1-3). In general, Kernel estimate provides a less biased home

    range estimation result than MCP (Swihart & Slade, 1997). However, when the sample size is

    large enough, the difference between the results from different estimate methods is not obvious

    (Boyle et al., 2009). In this research, there were thousands of location points for each coyote

    (Table 1-2), the large sample (under 95%) diminished the bias and resulted in fairly consistent

    home range sizes under both methods (Table 1-3). The average home range size for residents

    (mean = 27.14 km2, median = 27 km2, 95% CI = 19.00 – 35.27 km2; n = 7) was consistent with

  • 31

    Thornton et al (2004) average yearly home range size (mean = 24.8 km2, 95% CI = 16.96 –

    32.64 km2; n = 7), both carried out under 95% fixed KUD. The relative consistency between

    studies and similarity among genders (from my study) suggest that a breeding pair of coyotes if

    they are defending territory together in sub-tropical Florida require approximately 25 - 30 km2 on

    average.

    The resident coyotes in Florida have larger home range than the coyotes distributed in

    southwestern states at the similar latitudes, such as California and Arizona, but have similar

    home range size to the resident coyotes distributed in the southeastern states, such as South

    Carolina (Table 1-1, Figure 1-20). The estimation method, sample size of the studies, length of

    study, season of study, reproductive status, prey availability, and vegetation composition can all

    affect the size and shape of coyote home range. Due to the complexity of these variables, there

    are considerable difficulties and limited significance in comparing coyote home ranges from

    different studies carried out in different environments, other than gross generalities. Therefore, I

    have focused on comparison between gender, season, resident and transient within my study.

    After removing transients, I found no significant differences in resident home range sizes

    (95% or 50% KUD) between genders or seasons (Figure 1-21). However, in the spring, the

    difference between female and male home range under 95% KUD was marginally significant (U

    = 1, p = 0.11). The average home range size of females was tending to increase from the winter

    to the spring (U = 1.5, p = 0.08) and the majority were juvenile (three out of the four). Two of

    the female juveniles increased home ranges in the spring, inflating the overall average female

    home range (Table 1-4). These two juveniles interacted extensively and were likely siblings.

    Juvenile coyotes may have increased home range before dispersing (Harrison et al., 1991), and

    the dispersal could be the result of the increased aggressiveness from other juveniles in the same

  • 32

    litter as they grow older (Bekoff, 1977). These two coyotes had increasing average distance

    between each other from the winter to the spring, which may have been caused by increased

    aggressiveness, as well as exploratory behavior as they begin to disperse from their natal home

    range and search for available mates. In California, a study found that 1st year female coyotes

    started to enter proestrus in November, and that 50% of the 1st year female coyotes were in

    proestrus by February (Sacks, 2005). During the timeframe of my research it is likely that

    juveniles were entering or in proestrus during and searching mates. I show in the interaction

    analysis that one female juvenile frequently left her home ranges and traveled into one neighbor

    male resident home range. (Figure 1-13). This female may also have travelled across other

    coyote home ranges and had other interactions between her natal territory and the male resident

    visited. This exploratory behavior of visiting nearby territories may explain why home range

    sizes of female juveniles are possibly increasing during the spring season.

    Movement Rates and Circadian Rhythm

    In the sub-tropical environment of Florida, coyotes have high average hourly movement

    rates during dawn, dusk, and nocturnally, compared to relatively low rates in the day (Table 1-7,

    Figure 1-7). The dawn and the dusk periods by default are only 2 hours in length, while and the

    daytime is about 10 hours, this resulted in the similar cumulative travel distances among dawn,

    dusk, and day, showing that there are some periods during the day when considerable

    movements are made. The sum distance travelled at night is approximately the same as sum

    distances travelled during the dawn, day, and dusk (Table 1-8, Figure 1-8). The crepuscular and

    nocturnal movement rates in this study area are consistent with another Florida study that

    indicated coyote movement rates were 600 m/h crepuscularly and 630 m/h nocturnally but

    diurnal movements from my study were only 100 m/h on average compared to 300 m/h

  • 33

    (Thornton et al., 2004). Coyotes present similar circadian activity patterns as reported from many

    studies with higher rates at dusk, dawn, and night compared to the daytime (Kitchen et al., 2000;

    Hidalgo-Mihart et al., 2009; Arias-Del Razo et al., 2011). The coyotes in Florida were relatively

    less active during the day time. The avoidance of the diurnal movement could be explained by

    very open landscape with a small amount of shelter, combined with exposure to the strong

    tropical sun and high temperatures in Florida rangelands. Another reason could be coyote

    avoided getting shot by local hunters. The lower diurnal activity may also be due to difference in

    the land use, predominantly being agricultural and an increased amount of human activity

    compared to natural lands, as coyote activity can be strongly affected by humans. Kitchen et al.

    (2000) indicated that coyotes are less active during the day and more active at night but 8 years

    later in the same area when human activity was less coyote had increased their daytime activity.

    At my research sites there was recurrent horseback riding for cattle working, driving of trucks

    and tractors, sod cutting, and orange picking activity by humans. Coyote may decrease activity

    during the day to avoid encounters with humans that in Florida ranchlands are also known to

    have hunted them when seen.

    In most coyote circadian activity research, periods of interest were either divided into

    biological seasons such as breeding, gestation, pup rearing, and juvenile independence (Servin et

    al., 2003), or divided into climatic seasons such as spring, summer, fall, and winter (Gese et al.,

    1988). In Florida, the biological seasons of coyotes are not well ascertained, so I divided my

    research period into winter and spring. These two periods probably covered breeding/gestation

    and the beginning of whelping and pup rearing in Florida, with breeding and gestation occurring

    in the winter period and pup rearing more likely across spring (Main et al., 1999). The hourly

    movement rates of coyotes were higher in all time categories dusk, nocturnal, dawn and diurnal

  • 34

    in the spring than the movement rates in the corresponding time category in the winter (Table 1-

    9). As expected the cumulative travel distances in each time category show similar patterns to

    hourly movement rates, in that in the spring coyote traveled longer distances in most time

    categories than in the winter, except nocturnally when there was no significant difference (Table

    1-10). The non-difference in nocturnal distance travelled can be explained by the changes in

    night length with slower hourly movement rates in winter being compensated by length of night

    compared to faster hourly movements in spring in a shorter night. It has been suggested that

    coyote may spend less time in hunting and more time in resting in winter if carcasses and larger

    prey are available, as small mammal, fruits, and invertebrates become less abundant (Bekoff and

    Well, 1980; Gese et al., 1996). Reduced hourly activity in winter may also be the most efficient

    way to save energy output and improve individual survival and condition during harsher

    conditions (Shivik et al.,1997). In the cattle stocked rangelands of Florida, the majority of calves

    are born from October through February and access to both carcasses and afterbirth may alter the

    way coyote behave in winter. However, compared to many other regions of the US, Florida has

    an extremely mild winter and thermal energy costs and reduction in food resources may not be as

    taxing as other locations. The opinion that coyote reduce activity in winter in order to save

    energy may be valid but further investigation should be carried out on coyote breeding cycles in

    Florida. Although there are no adequate studies to describe the breeding seasons of coyote in

    Florida, the changes in coyote activity behavior could be related to the reproductive status. It is

    likely pro-estrus occurs sometime early in the year as daytime increases and in female coyotes

    this period can last 60-90 days (Kennelly, 1972). In many canids there are heightened levels of

    activity behavior preceding breeding during pro-estrus, including raised leg urination, ground

    scratching, howling and general activity (Thomson, 1992, Bekoff 1979), and if this period

  • 35

    coincided mostly with spring months (March 2015 to May 2015), it would explain the increased

    activity observed. Coyotes may have been patrolling home range more intensely and increasing

    above mentioned behaviors. Understanding the breeding phenology of coyote in Florida will

    enhance our knowledge of changes in activity patterns.

    Effects of Temperature and Rainfall on Coyote Activity

    The general relationship between temperature variation and coyote daily travel distance is

    complex because behaviors such as foraging, breeding, and territory patrol can all affect the

    distance coyote travel per day. One research study on the movement patterns of coyotes in

    Washington found an insignificant correlation between daily mean temperature and daily

    movement (Springer, 1982). In Florida I expected high temperatures to reduce activity, and after

    controlling for the random effects of location and individual coyote, I show that daily cumulative

    travel distance was significantly negatively correlated with daily mean temperature. This result

    seems to be contradictory to the conclusions from my seasonal home range and activity analysis

    which indicates that coyote have larger home ranges, higher hourly movement rates and longer

    cumulative travel distance in the spring, especially when the temperature increases from the

    winter to the spring. However, further investigation showed that in both winter and spring

    periods activity decreases with temperature but activity is overall higher in spring (Figure 1-1).

    I found that rain had an effect on coyote daily distance travelled and this may be because

    they don’t like getting wet, as a wet pelt has a significantly reduced insulating quality and

    decreases the total thermal resistance of the coat of the mammal (Webb & King, 1984). The

    effect of decreasing thermal resistance is more significant when environmental temperature is

    low, as has been shown in black-tailed deer (Odocoileus hemionus columbianus; Paker, 1987).

  • 36

    Once coyote get wet, the heat loss may increase and coyote may decide to find cover and in turn

    reducing daily movement.

    Individual Interactions

    Resident coyotes defend their territory from intruders from other groups and transients

    (Gese, 2001). Therefore, direct interactions among coyotes from different groups are infrequent.

    During this study resident coyotes from different groups with exclusive home ranges rarely

    encountered each other. However, there were numerous interactions between the female

    residents from the same group. There were two pairs of female residents in this study. The two

    female juveniles (F2 & F3) at Buck Island could be considered siblings because of their highly

    overlapped home ranges, the long-term repeated interactions, and being of the same age. Before

    February, these two juveniles were resting and moving together consistently. From February

    onwards one female (F3) began to expand her area of use (Figure 1-13), although there was still

    frequent interactions, the average distance between the female juveniles increased (Figure 1-12).

    A possible reason for the expanded active area and farther average distance between the siblings

    could be the pre-dispersal behavior of juveniles, a period of preparation before young coyotes

    leave their natal territory. There is a strong tendency for individuals to avoid others and to show

    increasing independence before the dispersal (Bekoff, 1977) and to show within territory family

    aggression between adults and siblings (Harrison et al., 1991). It is unknown that either F3 was

    forced by other sibling to expand her home range to avoid increasingly aggressive interactions or

    it could be that F3 was a more dominant coyote and capable of leaving the natal territory.

    Unfortunately, we do not have the breeder home range to define territorial boundaries the

    juveniles may have been safer within. The reason for the increasing average distance between

    these two coyotes could also be exploration in order to find available male coyotes. I

  • 37

    documented coyote F3 visiting M1 near her home range boundary and frequently traveled into

    M1 home range. At the same time, there was also one time that F2 left her home range and

    eventually traveled 7 km to the north into the home range of M5.

    Another pair consisted one female juvenile (F10) and one female adult (F9). These two

    coyotes also had highly overlapped home ranges and long-term interactions, however the core

    area did not have large proportion overlapping. The distances between these two coyotes did not

    show trend of increasing through the research period. One potential reason for the long term

    interactions could be less pressure from other members in the group, for example no siblings or

    the male resident died. It could also be that this juvenile was slow to develop and stayed within

    female adult home range as long as possible.

    The two transient coyotes had large home ranges with overlap with the resident coyote

    home ranges. Both these male transients were recorded interacting with other coyotes (Figure 1-

    17, Figure 1-18, Figure 1-19). Usually, transient coyotes are dispersing juvenile and transient’s

    movement can be restricted to the area between resident home ranges (Kamler & Gipson, 2000).

    However, M15 was already a 2-year old adult when he was captured in 2014 winter. The reason

    of the abnormal revisitings toward resident home range by transients can be that the residents

    lacked of the ability to defend the territory. Another potential explanation can be the that there is

    extraordinarily attractive food resource distributed in resident’s home range. Timm et al. (2004)

    discuss coyote visiting areas near suburban-wildland interface. The home range of the male

    resident (M13) was half surrounded by low density human community. The two times inferred

    interaction between M13 and M15 both happened near human community by the lake. The

    transient may have visited several times due to the attraction of the nearby human community

    offering a potential food resource to the coyote.

  • 38

    Table 1-1. Coyote home range sizes in different studies.

    Paper General Adult Juvenile Male Female Resident Transient Method Location Season

    Boisjoly et al., 2010 121±7,

    n=19

    2689±252,

    n=4

    100%

    MCP

    Eastern

    Quebec,

    Canada

    Annual

    Bowen, 1982 13.7±1.35, n=18 95%

    MCP

    Alberta,

    Canada Annual

    Chamberlain et al., 2000 10.01±1,

    n=16 24.68±7.48, n=10

    95%

    ADK Mississippi Spring

    Gehrt, 2009 4.95±0.34,

    n=84

    26.8±2.95,

    n=40

    95%

    MCP Illinois Annual

    Gese, 1988 11.3±0.78,

    n=56

    106.5±6.93,

    n=16

    95%

    MCP Colorado Annual

    Grinder & Krausman, 2001 12.6±3.5,

    n=13

    105.2±37.9,

    n=3

    95%

    MCP Arizona Annual

    Grubbs & Krausman, 2009 22.9±4.2, n=9 95%

    MCP Arizona Annual

    Grubbs & Krausman, 2009 26.8±5.1, n=9 95%

    FK Arizona Annual

    Harrison & Gilbert,

    1985 46.4±1.06, n=7 MCP* Maine

    Summe

    r

    Harrison et al., 1991 11.2±2.9, n=7 MCP* Maine Winter

    Jantz, 2001 10.61, n=14 95%

    ADK Alabama Annual

    Kamler et al.,

    2003 12.5±0.4, n=7

    95%

    MCP Texas Annual

    Kamler et al.,

    2003 8.9±1.2, n=7

    95%

    MCP Texas Annual

  • 39

    Table 1-1. Continued

    Paper General Adult Juvenile Male Female Resident Transient Method Location Season

    Riley et al., 2003

    4.69±1.

    31,

    n=28

    4.18±1.06,

    n=12

    6.17±1.59,

    n=22 2.84±0.66, n=18

    95%

    MCP California Annual

    Schrecengost,

    2007 30.5±8.6, n=18 20.61±5.4, n=16

    95%

    MCP South Carolina

    Schrecengost,

    2007 31.85±8.3, n=22 24.24±4.7, n=20 95% FK South Carolina

    Thornton et

    al., 2004 24.8±4, n=7 95% FK Florida Annual

    This research 24±5.6

    4, n=4

    31.33±6.4

    4, n=3

    20.33±6.0

    6, n=3

    32.25±4.6

    4, n=4

    27.14±4.

    15, n=7

    504±416.

    5, n=2 95% FK Florida

    Winter

    &

    Spring

    Note: MCP= Minimun convex polygon.

    ADK=Adaptive kernel utilization.

    FK= Fixed kernel utilization.

    KUD= Kernel utilization distribution.

    *= Proportion of points not descripted

    n= Sample size

    Unit: X ± SE km²

  • 40

    Table 1-2. Coyote capture records.

    Location

    Capture

    date

    Ag

    e

    Weight

    (kg)

    Length

    (cm)

    Gend

    er Description Data start Data end

    Fix

    Num

    1

    Buck Island

    Ranch

    11/11/201

    4 3+ 17.80 98 M

    Collar dropped and

    recovered

    11/12/20

    14

    5/12/201

    5 7,587

    2

    Buck Island

    Ranch

    11/11/201

    4

  • 41

    Table 1-3. Coyote overall home range summary.

    Note: MCP= Minimum convex polygon.

    KUD= Kernel utilization distribution.

    Unit: km².

    Coyote

    ID Location Gender Age

    MCP

    95%

    MCP

    50%

    KUD

    95%

    KUD

    50% Data start Data end

    Data

    Fix

    Number

    1 BuckIsland Male Adult 29 14 31 10 11/12/2014 5/12/2015 7,587

    2 BuckIsland Female Juvenile 26 3 23 2 11/12/2014 5/12/2015 7,235

    3 BuckIsland Female Juvenile 72 4 44 4 11/23/2014 5/23/2015 7,411

    5 BuckIsland Male Adult 15 5 20 1 11/25/2014 5/25/2015 7,538

    8 Blackbeard Male Adult 963 523 921 125 12/6/2014 5/11/2015 6,391

    9 Blackbeard Female Adult 32 11 35 10 12/6/2014 4/1/2015 4,667

    10 Blackbeard Female Juvenile 30 6 27 5 12/7/2014 6/6/2015 7,326

    13 Lightsey Male Adult 10 3 10 2 11/14/2014 5/14/2015 7,527

    15 Lightsey Male Adult 92 21 88 13 12/14/2014 4/12/2015 4,953

  • 42

    Table 1-4. Coyote seasonal home range summary.

    Coyote ID Gender Age KUD 95% Winter KUD 50% Winter KUD 95% Spring KUD 50% Spring

    1 Male Adult 31.65 10.08 30.94 7.79

    2 Female Juvenile 14.09 1.14 41.69 5.02

    3 Female Juvenile 25.55 2.24 58.24 6.18

    5 Male Adult 37.22 2.99 10.18 2.05

    8 Male Adult 686.28 108.45 439.71 30.47

    9 Female Adult 35.27 9.84 34.79 8.93

    10 Female Juvenile 26.23 4.84 27.63 4.95

    13 Male Adult 8.70 1.87 10.14 2.35

    15 Male Adult 61.13 11.13 118.33 19.29

    Note: KUD= Kernel utilization distribution.

    Unit: km²

  • 43

    Table 1-5. Coyote home range season, gender Mann-Whitney U test.

    Male 95% Female 95% U p-value

    Winter 25.86 25.29 5 0.86

    Spring 17.09 40.59 1 0.11

    U 3 1.5

    p-value 0.66 0.08

    Note: KUD= Kernel utilization distribution.

    Unit: km²

    Table 1-6. Coyote core use area season, gender Mann-Whitney U test.

    Male 50% Female 50% U p-value

    Winter 4.51 4.98 7 0.86

    Spring 4.07 6.27 3 0.37

    U 3 5 p-value 0.64 0.46

    Note: KUD= Kernel utilization distribution.

    Unit: km²

    Table 1-7. Hourly movement rate, time period of the day and season Linear Mixed-Effects

    Model analysis. Value Std.Error DF t-value p-value

    (Intercept) 21.62 0.95 5899 22.77 0.00

    Winter-Spring -2.17 0.49 5899 -4.44 0.00

    Diurnal-Dawn -10.89 0.52 5899 -20.91 0.00

    Dusk-Dawn 5.26 0.52 5899 10.08 0.00

    Nocturnal-Dawn 5.37 0.52 5899 10.32 0.00

    Table 1-8. Cumulative travel distance, time period of the day and season Linear Mixed-Effects

    Model analysis. Value Std.Error DF t-value p-value

    (Intercept) 30.48 2.03 5899 15.03 0.00

    Winter-Spring -2.99 0.99 5899 -3.01 0.00

    Diurnal-Dawn 2.90 1.06 5899 2.73 0.01

    Dusk-Dawn 7.51 1.06 5899 7.06 0.00

    Nocturnal-Dawn 51.57 1.06 5899 48.65 0.00

  • 44

    Table 1-9. Hourly movement rate, time period of the day and season Tukey Honest Significant

    Difference analysis.

    Estimate Std. Error

    z

    value Pr(>|z|) Significant

    Winter.Dawn - Spring.Dawn -2.17 0.49 -4.44 < 0.001 ***

    Spring.Diurnal - Spring.Dawn -10.89 0.52 -20.91 < 0.001 ***

    Winter.Diurnal - Spring.Dawn -12.66 0.49 -25.99 < 0.001 ***

    Spring.Dusk - Spring.Dawn 5.26 0.52 10.08 < 0.001 ***

    Winter.Dusk - Spring.Dawn 1.87 0.49 3.83 0.00 **

    Spring.Nocturnal - Spring.Dawn 5.37 0.52 10.33 < 0.001 ***

    Winter.Nocturnal - Spring.Dawn 2.77 0.49 5.69 < 0.001 ***

    Spring.Diurnal - Winter.Dawn -8.72 0.49 -17.91 < 0.001 ***

    Winter.Diurnal - Winter.Dawn -10.50 0.45 -23.42 < 0.001 ***

    Spring.Dusk - Winter.Dawn 7.43 0.49 15.21 < 0.001 ***

    Winter.Dusk - Winter.Dawn 4.03 0.45 8.99 < 0.001 ***

    Spring.Nocturnal - Winter.Dawn 7.53 0.49 15.49 < 0.001 ***

    Winter.Nocturnal - Winter.Dawn 4.94 0.45 11.01 < 0.001 ***

    Winter.Diurnal - Spring.Diurnal -1.78 0.49 -3.64 0.01 **

    Spring.Dusk - Spring.Diurnal 16.15 0.52 30.95 < 0.001 ***

    Winter.Dusk - Spring.Diurnal 12.76 0.49 26.16 < 0.001 ***

    Spring.Nocturnal - Spring.Diurnal 16.26 0.52 31.26 < 0.001 ***

    Winter.Nocturnal - Spring.Diurnal 13.66 0.49 28.04 < 0.001 ***

    Spring.Dusk - Winter.Diurnal 17.93 0.49 36.71 < 0.001 ***

    Winter.Dusk - Winter.Diurnal 14.53 0.45 32.37 < 0.001 ***

    Spring.Nocturnal - Winter.Diurnal 18.03 0.49 37.09 < 0.001 ***

    Winter.Nocturnal - Winter.Diurnal 15.44 0.45 34.43 < 0.001 ***

    Winter.Dusk - Spring.Dusk -3.39 0.49 -6.94 < 0.001 ***

    Spring.Nocturnal - Spring.Dusk 0.11 0.52 0.20 1.00 #

    Winter.Nocturnal - Spring.Dusk -2.49 0.49 -5.10 < 0.001 ***

    Spring.Nocturnal - Winter.Dusk 3.50 0.49 7.19 < 0.001 ***

    Winter.Nocturnal - Winter.Dusk 0.90 0.45 2.01 0.47 #

    Winter.Nocturnal - Spring.Nocturnal -2.60 0.49 -5.34 < 0.001 ***

    Note: ** means p

  • 45

    Table 1-10. Cumulative travel distance, time period of the day and season Tukey Honest

    Significant Difference analysis.

    Estimate Std. Error

    z

    value Pr(>|z|) Significant

    Winter.Dawn - Spring.Dawn -2.99 0.99 -3.01 0.05 #.

    Spring.Diurnal - Spring.Dawn 2.90 1.06 2.74 0.11 #

    Winter.Diurnal - Spring.Dawn -4.63 0.99 -4.67

  • 46

    Table 1-11. Daily mean temperature and rainfall interactive effect on daily cumulative travel

    distance Linear Mixed-Effect Model analysis. Value Std.Error DF t-value p-value

    (Intercept) 120.29 7.20 1301 16.71 0.00

    Temperature -0.12 0.08 1301 -1.52 0.13

    Rain 3.75 12.29 1301 0.31 0.76

    Temperature:Rain -0.10 0.17 1301 -0.55 0.58

    Table 1-12. Daily mean temperature and rainfall main effects on daily cumulative travel

    distance Linear Mixed-Effect Model analysis. Value Std.Error DF t-value p-value

    (Intercept) 121.50 6.85 1302 17.73 0.00

    Temperature -0.13 0.07 1302 -1.94 0.05

    Rain -2.96 1.46 1302 -2.03 0.04

    Table 1-13. Daily mean temperature, rainfall, and season interactive effect on daily cumulative

    travel distance Linear Mixed-Effect Model analysis. Value Std.Error DF t-value p-value

    (Intercept) 141.15 15.21 1297 9.28 0.00

    Temperature -0.36 0.19 1297 -1.85 0.06

    SeasonWinter 5.94 16.49 1297 0.36 0.72

    Rain 7.28 48.42 1297 0.15 0.88

    Temperature:SeasonWinter -0.24 0.23 1297 -1.01 0.31

    Temperature:Rain -0.11 0.63 1297 -0.17 0.87

    SeasonWinter:Rain 14.33 51.44 1297 0.28 0.78

    Temperature:SeasonWinter:Rain -0.24 0.68 1297 -0.36 0.72

    Table 1-14. Records of interactions of coyotes from two different home ranges.

    Coyote ID Location Date Time Distance (m)

    M1 & F3 BuckIsland 3/10/2015 01:30 124

    M8 & F9 Blackbeard 12/22/2014 05:00 105

    M8 & F10 Blackbeard 12/22/2014 04:30 137

    M13 & M15 Lightsey 12/15/2014 08:00 127

    M13 & M15 Lightsey 4/5/2015 05:00 95

  • 47

    Figure 1-1. Research sites.

  • 48

    Figure 1-2. Buck Island coyote home ranges.

  • 49

    Figure 1-3. Lightsey coyote home ranges.

  • 50

    Figure 1-4. Blackbeard coyote home ranges.

  • 51

    Figure 1-5. Circadian activity of coyote hourly movement in winter and spring.

    0

    200

    400

    600

    800

    1000

    1200

    1400

    1600

    0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

    mo

    vem

    ent

    rate

    (m

    ean

    + 9

    5%

    co

    nfi

    den

    ce i

    nte

    rval

    m/h

    r)

    time (hr)

    November 2014 - February 2015 March 2015 - June 2015

  • 52

    Figure 1-6. Coyote hourly movement rates in different seasons and time periods. Note: each box presents minimum, lower quartile,

    median, upper quartile, maximum from bottom to top.

  • 53

    Figure 1-7. Coyote hourly movement rates in different seasons and time periods Tukey Honest Significant Difference. Note: mean

    value and 95% confidence interval.

  • 54

    Figure 1-8. Coyote cumulative travel distance in different seasons and time periods. Note: each box presents minimum, lower quartile,

    median, upper quartile, maximum from bottom to top.

  • 55

    Figure 1-9. Coyote cumulative travel distance in different seasons and time periods Tukey Honest Significant Difference. Note: mean

    value and 95% confidence interval.

  • 56

    Figure 1-10. Predicted temperature and rainfall effect on daily travel distance.

    10500

    11000

    11500

    12000

    12500

    13000

    13500

    15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

    Dai

    ly t

    rave

    l dis

    tan

    ce (

    m/d

    ay)

    Temperature (℃)

    Rain & Temperature effect on daily movement

    no rain rain

  • 57

    Figure 1-11. Coyote daily travel distance by temperature and season.

  • 58

    Figure 1-12. Instantaneous distance between female juvenile coyote F2 and F3 every 30mins.

    0

    2000

    4000

    6000

    8000

    10000

    12000

    14000

    16000

    Dis

    tance

    bet

    wee

    n c

    oyo

    tes

    (m)

    Time (date)

    Distance between F2 & F3

  • 59

    Figure 1-13. Coyote F3 travel out of the home range on 3/13/2015.

  • 60

    Figure 1-14. Coyote F3 & M1 interaction on 3/10/2015.

  • 61

    Figure 1-15. Coyote F2 travel out of the home range on 4/18/2015.

  • 62

    Figure 1-16. Instantaneous distance between female juvenile coyote F9 and F10 every 30mins.

    0

    1000

    2000

    3000

    4000

    5000

    6000

    7000

    8000

    Dis

    tan

    ce b

    etw

    een c

    oyo

    tes

    (m)

    Time (date)

    Distance between F9 & F10

  • 63

    Figure 1-17. Coyote F8 & F9 & F10 interaction on 12/22/2014.

  • 64

    Figure 1-18. Coyote M13 & M15 interaction on 12/15/2014.

  • 65

    Figure 1-19. Coyote M13 & M15 interaction on 4/5/2015.

  • 66

    Figure 1-20. Coyote home ranges in southern states.

    0

    5

    10

    15

    20

    25

    30

    35

    4095%

    hom

    e ra

    nge

    (Mea

    n +