A Brief History of Coyote A Brief History of Coyote Research at HoplandResearch at Hopland

Robert M. TimmRobert M. TimmExtension Wildlife Specialist Extension Wildlife Specialist emeritusemeritusUC Hopland Res. & Ext. CenterUC Hopland Res. & Ext. Center

Coyote Research at HoplandCoyote Research at Hoplandmid-1970s to 2007mid-1970s to 2007

caca 120 publications 120 publications

Most studies were conducted by UC Davis and Most studies were conducted by UC Davis and UC Berkeley faculty and graduate students UC Berkeley faculty and graduate students

in cooperation with USDAin cooperation with USDA

UC’s Experience at HoplandUC’s Experience at Hopland

1951 – 1965: essentially no coyote loss1951 – 1965: essentially no coyote loss1965 – 1975: coyote losses common1965 – 1975: coyote losses common1985: return of mountain lions to area1985: return of mountain lions to area

1990s & 2000s: Loss of ~10-15% of lamb 1990s & 2000s: Loss of ~10-15% of lamb crop annually despite employing many crop annually despite employing many non-lethal measures and all legal lethal non-lethal measures and all legal lethal methods methods

Sheep & Lambs Inventory, Mendocino County

0

20000

40000

60000

80000

100000

120000

140000

160000

180000

200000

1930 1940 1945 1950 1960 1970 1980 1990 2000 2010

Year

No. of Head

Potential Reasons for Sheep Potential Reasons for Sheep Industry Decline:Industry Decline:

Lamb & Wool PricesLamb & Wool Prices Real Estate Values & Rancher DemographicsReal Estate Values & Rancher Demographics Predation LossesPredation Losses

Nesse et al. (1976), Wagner (1988)

Predation LossesPredation Losses Increasing range and populations of Increasing range and populations of

coyotescoyotes Fewer predator control tools and methodsFewer predator control tools and methods Less predator control effort, and Less predator control effort, and

decreased ability to suppress coyote decreased ability to suppress coyote numbersnumbers

““Snowball effect”Snowball effect”

Increasing range and Increasing range and populations of coyotespopulations of coyotes

Inland vs. Coastal RangelandsInland vs. Coastal Rangelands

19701970 ShootingShooting Foothold trapsFoothold traps SnaresSnares Toxic draw stationsToxic draw stations Place baitsPlace baits Sodium cyanide ejectorsSodium cyanide ejectors Den huntingDen hunting

Coyote Control Methods - Coyote Control Methods - CACA

after Connolly (1981)after Connolly (1981)

Methods of Lethal Coyote ControlMethods of Lethal Coyote Control and Percentage of Coyotes Takenand Percentage of Coyotes Taken by Federal Wildlife Damage Control FY 1971 (U.S.)by Federal Wildlife Damage Control FY 1971 (U.S.)

37.5%37.5% Foothold trapsFoothold traps27.3%27.3% Sodium cyanide ejectorsSodium cyanide ejectors 9.1%9.1% Aerial huntingAerial hunting 9.0%9.0% Other toxicantsOther toxicants 7.0%7.0% Den huntingDen hunting 6.5%6.5% Ground shootingGround shooting 3.3%3.3% SnaresSnares 0.4%0.4% Use of dogsUse of dogs

Non-lethal methods usedNon-lethal methods used(by ranchers)(by ranchers)

FencingFencing Pasture selectionPasture selection Increased protection at lambing and Increased protection at lambing and

soon thereaftersoon thereafter Timing of breeding / lambingTiming of breeding / lambing

1970s1970s

USDA funding to UC Davis faculty –USDA funding to UC Davis faculty –

William M. LonghurstWilliam M. LonghurstWalter E. HowardWalter E. Howard

facilitated establishment of coyote facilitated establishment of coyote research at Hopland research at Hopland

beginning about 1972.beginning about 1972.

Connolly, G. E. and W. M. Longhurst. 1975. Connolly, G. E. and W. M. Longhurst. 1975. The effects of control on coyote populations. The effects of control on coyote populations. Div. of Agric. Sci. Bulletin 1872, Univ. of California. 37 pp.Div. of Agric. Sci. Bulletin 1872, Univ. of California. 37 pp.

To exterminate coyote populations by lethal removal, >75% of To exterminate coyote populations by lethal removal, >75% of coyotes would need to be harvested annually for approximately coyotes would need to be harvested annually for approximately 50 years.50 years. * * * * * *

Nesse, G. E., W. M. Longhurst, and W. E. Howard. 1976. Nesse, G. E., W. M. Longhurst, and W. E. Howard. 1976. Predation and the sheep industry in California 1974-1976. Predation and the sheep industry in California 1974-1976. Agric. Exper. Sta. Bulletin 1878, Univ. of Calif. 63 pp.Agric. Exper. Sta. Bulletin 1878, Univ. of Calif. 63 pp.

Survey data of No. California sheep ranchers indicated that Survey data of No. California sheep ranchers indicated that coyotes by far were the largest predator of sheep and lambs, coyotes by far were the largest predator of sheep and lambs, accounting for 82% of predation losses.accounting for 82% of predation losses.

Survey of CA Sheep RanchersSurvey of CA Sheep Ranchers

Most critical concerns to ranchers Most critical concerns to ranchers regarding sustainability: regarding sustainability: ““most important production problem”most important production problem”

Predation (50% of ranchers)Predation (50% of ranchers)Property Taxes (15% of ranchers)Property Taxes (15% of ranchers)Market Prices (13% of ranchers)Market Prices (13% of ranchers)

after Nesse et al. (1976)after Nesse et al. (1976)

Connolly, G.E., R.M. Timm, W.E. Howard, and W.M. Longhurst. 1976. Connolly, G.E., R.M. Timm, W.E. Howard, and W.M. Longhurst. 1976.

Sheep killing behavior of captive coyotes. Sheep killing behavior of captive coyotes. J. Wildl. Management 40:400-407.J. Wildl. Management 40:400-407.

photos: G. E. Connolly

19801980 ShootingShooting Foothold trapsFoothold traps SnaresSnares Toxic draw stations Toxic draw stations –– banned 1972banned 1972 Place baits Place baits –– banned 1972banned 1972 Sodium cyanide ejectors Sodium cyanide ejectors – banned 1972-1975, – banned 1972-1975,

19981998 Den hunting Den hunting – prohibited by USDI in 1979– prohibited by USDI in 1979

Coyote Control Methods - Coyote Control Methods - CACA

1980s1980sScrivner, J.H., W.E. Howard, R. Teranishi, and D.B. Fagre. 1985. Scrivner, J.H., W.E. Howard, R. Teranishi, and D.B. Fagre. 1985. Toward a more effective coyote lure. Toward a more effective coyote lure. Rangelands 7:52-54.Rangelands 7:52-54.

Coyotes were highly Coyotes were highly attracted to short-chain fatty attracted to short-chain fatty acids, a product of protein acids, a product of protein decomposition.decomposition.

One of the most successful One of the most successful lures was lures was trimethylammonium trimethylammonium decanoate (TMAD)decanoate (TMAD)

Fagre, D.B., B.A. Butler, W.E. Howard, and R. Teranishi. 1981. Fagre, D.B., B.A. Butler, W.E. Howard, and R. Teranishi. 1981. Behavioral responses of coyotes to selected odors and tastes. Behavioral responses of coyotes to selected odors and tastes. Proc. Worldwide Furbearer Conf. Vol. 2, pp. 966-983. Proc. Worldwide Furbearer Conf. Vol. 2, pp. 966-983.

Aversive conditioning of coyotes was ineffective in preventing Aversive conditioning of coyotes was ineffective in preventing predatory attacks, as was the application of repellents. predatory attacks, as was the application of repellents.

Scrivner, J.H., W.E. Howard, A.H. Murphy, and J.R. Hays. 1985. Scrivner, J.H., W.E. Howard, A.H. Murphy, and J.R. Hays. 1985. Sheep losses to predators on a California rangeSheep losses to predators on a California range. . J. Range Manage. 38:418-421.J. Range Manage. 38:418-421.

Sheep and lamb losses for an 11-year period were analyzed; for all Sheep and lamb losses for an 11-year period were analyzed; for all known ewe and lamb deaths, 45% and 26% were killed by known ewe and lamb deaths, 45% and 26% were killed by predators. Of predator kills, coyotes caused 89% of deaths, with predators. Of predator kills, coyotes caused 89% of deaths, with more sheep and lambs killed Oct – Mar than from Apr – Sept.more sheep and lambs killed Oct – Mar than from Apr – Sept.

1990s1990sSymposiumSymposium::Predator Management in North Predator Management in North Costal CaliforniaCostal California

March 1990March 1990

HREC guard dog ‘Brutus’ with flock

Sacks, B.N., K.M. Blewjas, and M.M. Jaeger. 1999. Sacks, B.N., K.M. Blewjas, and M.M. Jaeger. 1999. Relative vulnerability of coyotes to removal methods on a Relative vulnerability of coyotes to removal methods on a northern California sheep ranch. northern California sheep ranch. J. Wildl. Manage. 63:939-949.J. Wildl. Manage. 63:939-949.

Sacks, B.N., M.M. Jaeger, J.C.C. Neale, and D.R. McCullough. Sacks, B.N., M.M. Jaeger, J.C.C. Neale, and D.R. McCullough. 1999. 1999. Territoriality and breeding status of coyotes relative to sheep Territoriality and breeding status of coyotes relative to sheep production. production. J. Wildl. Manage. 63:593-605.J. Wildl. Manage. 63:593-605.

Alpha coyotes (especially males) were significant predators of Alpha coyotes (especially males) were significant predators of sheep and lambs, and were the most difficult coyotes to control. sheep and lambs, and were the most difficult coyotes to control. Selective removal of problem individuals would reduce losses, Selective removal of problem individuals would reduce losses, especially if timed strategically.especially if timed strategically.

Healthy population of bobcats existed at HREC alongside coyotes Healthy population of bobcats existed at HREC alongside coyotes with apparently little competitive overlap.with apparently little competitive overlap.

Timm, R. M. 1999. Timm, R. M. 1999. Controlling coyote predation on sheep in California: a model Controlling coyote predation on sheep in California: a model strategy. strategy. Final Report to CA Dept. of Pesticide Regulation.Final Report to CA Dept. of Pesticide Regulation.

Used the Livestock Protection Collar (active ingredient: sodium monofluoroacetate – ‘1080’) as the sole lethal tool to selectively remove problem coyotes, in conjunction with guard llamas. Established a local Predator Research Advisory Committee.

Timm, R. M., and G. E. Connolly. 2001. Timm, R. M., and G. E. Connolly. 2001. Sheep-killing coyotes a continuing dilemma for ranchersSheep-killing coyotes a continuing dilemma for ranchers. . Calif. Agriculture 55:26-31Calif. Agriculture 55:26-31

Proposition 4 (Nov. 1998) Proposition 4 (Nov. 1998) CaliforniaCalifornia

Banned use of foothold traps, Banned use of foothold traps, including in research including in research

(Exception: public safety emergency (Exception: public safety emergency use)use)

Banned use of sodium cyanide and Banned use of sodium cyanide and 1080 for control of predators1080 for control of predators

20002000 ShootingShooting Foothold trapsFoothold traps – banned 1998– banned 1998 SnaresSnares Toxic draw stations Toxic draw stations Place baits Place baits Sodium cyanide ejectors Sodium cyanide ejectors Den hunting Den hunting

Coyote Control Methods - Coyote Control Methods - CACA

Knowlton, F. F., E. M. Gese, and M. M. Jaeger. 1999. Knowlton, F. F., E. M. Gese, and M. M. Jaeger. 1999. Coyote depredation control: an interface between biology and Coyote depredation control: an interface between biology and management. management. J. Range Manage. 52:398-412.J. Range Manage. 52:398-412.

A very thorough, science-based summary of our A very thorough, science-based summary of our knowledge of coyotes and their management. knowledge of coyotes and their management. Integrates HREC research with other research from Integrates HREC research with other research from various localitiesvarious localities. .

2000s2000sWilliams, C.L., K. Blewjas, J.J. Johnston, and M.M. Jaeger. Williams, C.L., K. Blewjas, J.J. Johnston, and M.M. Jaeger. 2003. 2003. A coyote in sheep’s clothing: predator identification A coyote in sheep’s clothing: predator identification from saliva. from saliva. Wildl. Soc. Bull. 31:926-932.Wildl. Soc. Bull. 31:926-932.

DNA from coyote saliva can provide positive identification of individual coyotes that have killed prey, chewed bait delivery devices, or bitten people or pets.

K.M. Blejwas, C.L. Williams, G.T. Shin, D.R. McCullough, and M.M. Jaeger. 2006. Salivary DNA evidence convicts breeding male coyotes of killing sheep. J. Wildl. Manage. 70(4):1087-1093.

A. R. Berentsen, R. M. Timm, and R. H. Schmidt. 2007. A. R. Berentsen, R. M. Timm, and R. H. Schmidt. 2007. The Coyote Lure Operative Device revisited: a fresh look The Coyote Lure Operative Device revisited: a fresh look at an old idea. at an old idea. Calif. Agriculture 61(1):20-23.Calif. Agriculture 61(1):20-23.

photo: Guy E. photo: Guy E. ConnollyConnolly