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Rivers, lakes and springsRivers, lakes and springs

Florida: land of waterFlorida: land of water

Inland and coastalInland and coastal

Flat topography, porous bedrock andFlat topography, porous bedrock andabundant rainfall create complexabundant rainfall create complex

array of aquatic habitatsarray of aquatic habitats

Biologically richBiologically rich

Apalachicola, Suwannee, St. Johns,Apalachicola, Suwannee, St. Johns,Myakka, Myakka, OklawahaOklawaha, Kissimmee,, Kissimmee,Loxahatchee, St. Loxahatchee, St. MarysMarys,,WithlacoocheeWithlacoochee

More than 1700 rivers in FloridaMore than 1700 rivers in Florida

Larger rivers: Larger rivers: blackwater blackwater and mostand mostdischarge directly into seadischarge directly into sea

Of 23 major rivers that dischargeOf 23 major rivers that dischargeinto sea, 21 are located on the Gulfinto sea, 21 are located on the Gulfcoast.coast.

Classification of FloridaClassification of Florida’’s rivers and streamss rivers and streams

•• velocity of flow velocity of flow

•• substratum substratum

•• dissolved oxygen concentration dissolved oxygen concentration

•• water hardness (concentration of dissolved salts; mg/kg) water hardness (concentration of dissolved salts; mg/kg)

Variation in these variables determine theVariation in these variables determine thesuitability of a particular river or stream for varioussuitability of a particular river or stream for variousorganisms.organisms.

Sand-bottomed steams:Sand-bottomed steams:

most widely distributedmost widely distributed

moderate to swift flowsmoderate to swift flows

slightly acidic (pH 5.7-7.4)slightly acidic (pH 5.7-7.4)

shifting sand substratesshifting sand substrates

WithlacoocheeWithlacoochee, Hillsborough, Myakka, and, Hillsborough, Myakka, andOklawaha Oklawaha riversrivers

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Canals:Canals:

artificial waterways, standing water:artificial waterways, standing water:

Caloosahatchee Caloosahatchee River, Kissimmee River,River, Kissimmee River,

TamiamiTamiami, Miami canals, Miami canals

Calcareous streamsCalcareous streams::

spring originspring origin

cool & clear, alkaline (pH 7.0-8.2)cool & clear, alkaline (pH 7.0-8.2)

Suwannee, Santa Fe, St. MarkSuwannee, Santa Fe, St. Mark’’s riverss rivers

Large rivers:Large rivers:

turbid, high silt and clay loadsturbid, high silt and clay loads

Apalachicola, St. Johns, EscambiaApalachicola, St. Johns, Escambiariversrivers

Swamp-and-bog streams:Swamp-and-bog streams:

acidic (pH 3.8-6.5), sluggish acidic (pH 3.8-6.5), sluggish

SteinhatcheeSteinhatchee, St. Mary, St. Mary’’ss

Lakes and ponds:Lakes and ponds:

Porous limestone gradually dissolves inPorous limestone gradually dissolves incontact with water.contact with water.

Vast underground waterways formedVast underground waterways formedbeneath much of state.beneath much of state.

Lakes and ponds:Lakes and ponds:

Subsidence, collapse of underground cavitiesSubsidence, collapse of underground cavitiesresults in sinkholes or in shallow lakes.results in sinkholes or in shallow lakes.

Karst Karst topography: landscape marked bytopography: landscape marked bysinkholes and caves.sinkholes and caves.

Estimated 7,800 lakes in FloridaEstimated 7,800 lakes in Florida

Majority are small:Majority are small: only 5 with surface areas only 5 with surface areasgreater than 40 square milesgreater than 40 square miles

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Most are shallowMost are shallow:: average depth 15-20 feet average depth 15-20 feetLake Okeechobee: max. depth < 5 metersLake Okeechobee: max. depth < 5 meters

More than half of all the lakes occur in a 14-More than half of all the lakes occur in a 14-county area of central and north Florida.county area of central and north Florida.

FloridaFlorida’’s lakes: most are seepage lakes, nos lakes: most are seepage lakes, noinflow or outflow.inflow or outflow.

Gamut of lake types:Gamut of lake types:

Ultra-oligotrophicUltra-oligotrophic: extremely poorly nourished: extremely poorly nourished

OligotrophicOligotrophic: poorly nourished: poorly nourished

Hyper-eutrophicHyper-eutrophic: extremely well nourished.: extremely well nourished.

FloridaFloridaRainfall varies seasonally and annually. LakeRainfall varies seasonally and annually. Lakeevaporation fairly constant.evaporation fairly constant.

Result: dry years are frequent and rainfallResult: dry years are frequent and rainfalldeficiencies can be severe.deficiencies can be severe.

““NormalNormal”” years do not exist and some lakes years do not exist and some lakesfluctuate more than others, some lakes willfluctuate more than others, some lakes willdisappear.disappear.

FloridaFlorida’’s lakes and waterways: impacted bys lakes and waterways: impacted byexotic water plants.exotic water plants.

Water hyacinth (Water hyacinth (Eichhornia crassipesEichhornia crassipes))

Hydrilla Hydrilla ((Hydrilla verticillataHydrilla verticillata))

Asiatic grass carp: eat Asiatic grass carp: eat hydrillahydrilla

Control with herbicides relatively unsuccessful.Control with herbicides relatively unsuccessful.

FloridaFlorida’’s lakes:s lakes: extremely valuable natural extremely valuable naturalresourcesresources

Support diverse flora and faunaSupport diverse flora and fauna

Bathing, boating, skiing, fishing,Bathing, boating, skiing, fishing,irrigation and drinking.irrigation and drinking.

Growing human population. Water useGrowing human population. Water useand water quality will become majorand water quality will become majorissues.issues.

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Florida:Florida:Over 300 named springs in north andOver 300 named springs in north andcentral regions.central regions.

Springs are artesian.Springs are artesian.

Some holes open into caverns.Some holes open into caverns.

Significant differences in physical andSignificant differences in physical andchemical features of springs.chemical features of springs.

Largest springs are Largest springs are ““first-magnitudefirst-magnitudespringssprings””

Flow rates of > 3 million gallons of waterFlow rates of > 3 million gallons of waterper hour.per hour.

Florida: 27 first-magnitude springsFlorida: 27 first-magnitude springs

Homosassa SpringsHomosassa Springs

Ichetuchknee Ichetuchknee SpringsSprings

Silver SpringsSilver Springs

Juniper SpringsJuniper Springs

Larger springs: major tourist attractionsLarger springs: major tourist attractions

Fishing, snorkeling, tubing, swimmingFishing, snorkeling, tubing, swimmingand cave diving.and cave diving.

Silver Glen SpringsSilver Glen Springs

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Clear, warm waterClear, warm water

Constant temperature: 68-73° FahrenheitConstant temperature: 68-73° Fahrenheit

During cold spells water is warmer than theDuring cold spells water is warmer than thefreezing air temperature: springs attract largefreezing air temperature: springs attract largenumbers of manatees.numbers of manatees.

Belted kingfisher: Perch hunts, divesBelted kingfisher: Perch hunts, divesheadfirst for small fish, hover-like flight,headfirst for small fish, hover-like flight,distinctive rattle calldistinctive rattle call

Hole nestersHole nesters

Southern bald eagleSouthern bald eagle

Estimated 500 pairs inEstimated 500 pairs inUS in early 1960sUS in early 1960s

Banning of DDT in 1972Banning of DDT in 1972halted decline: 10-foldhalted decline: 10-foldincrease in USincrease in US

Florida has played an important roleFlorida has played an important rolein recovery.in recovery.

Florida has largest bald eagleFlorida has largest bald eaglepopulation in lower 48 states.population in lower 48 states.

Florida: number of active nestsFlorida: number of active nests

1972: 1201972: 120

1978: 3191978: 319

1991: 6231991: 623

1999: 1,043 (historical levels)1999: 1,043 (historical levels)

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Habitat: Habitat: suitable nest and perch sites in suitable nest and perch sites in proximity to large, open proximity to large, open waterbodieswaterbodies

DIETDIET

North-central Florida: freshwater catfish andNorth-central Florida: freshwater catfish andAmerican cootAmerican coot

Florida Bay: sea catfish, mullet, andFlorida Bay: sea catfish, mullet, andassorted wading birdsassorted wading birds

Fish are snatched from water by talonsFish are snatched from water by talons

Bald eagle: natural historyBald eagle: natural historySpectacular courtship displays: aerialSpectacular courtship displays: aerial

Long-term fidelity to nesting territoriesLong-term fidelity to nesting territories

Clutch size: 2Clutch size: 2

Incubation: 35 daysIncubation: 35 days

Fledging: 77 daysFledging: 77 days

Juvenile eagles disperse northJuvenile eagles disperse north

One-third of marked birds sighted more thanOne-third of marked birds sighted more than1,000 miles north1,000 miles north

South Carolina to Prince Edward Island,South Carolina to Prince Edward Island,CanadaCanada

Return to Florida after 2-3 yearsReturn to Florida after 2-3 years

Vulnerability:Vulnerability:•• Gunshot woundsGunshot wounds

•• Collisions with vehicles, power linesCollisions with vehicles, power lines

•• Bioaccumulation of contaminantsBioaccumulation of contaminants

•• Disturbance in early stages of breedingDisturbance in early stages of breeding

•• Nest abandonmentNest abandonment

•• High levels of boat activity may limitHigh levels of boat activity may limitforaging areasforaging areas

OspreyOsprey

Occur in Florida bothOccur in Florida bothas nesting species andas nesting species andmigrantsmigrants

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Major nesting areas in Florida:Major nesting areas in Florida:

Nest along Gulf Coast from ApalachicolaNest along Gulf Coast from ApalachicolaRiver to Keys;River to Keys;

Atlantic coast from St. MaryAtlantic coast from St. Mary’’s River tos River toMerritt Island;Merritt Island;

and St. Johnand St. John’’s and Kissimmee rivers.s and Kissimmee rivers.

Nests constructed in tops of large living andNests constructed in tops of large living anddead trees. Will also use man-madedead trees. Will also use man-madestructures: utility poles, radio towers, channelstructures: utility poles, radio towers, channelmarkers.markers.

Elaborate courtship flights in air over nestElaborate courtship flights in air over nestsites.sites.

Male will bring fish to its mate.Male will bring fish to its mate.

Clutch size: 3Clutch size: 3

Fledge: 55 days, continue to be fed until 90-Fledge: 55 days, continue to be fed until 90-100 days100 days

50-60% of all active nests fledge 1 or > 50-60% of all active nests fledge 1 or > ygyg

Diet:Diet:

Prey 7-16 inches long (catfish, crappie,Prey 7-16 inches long (catfish, crappie,sunfish, mullet, shad)sunfish, mullet, shad)

Capture by diving into water with talonsCapture by diving into water with talonsextended.extended.

Will orient prey in talons, align with bodyWill orient prey in talons, align with bodyof bird when carrying prey back to perch.of bird when carrying prey back to perch.

Conservation:Conservation:

Estimate of 1,500 - 2,000 pairs in FloridaEstimate of 1,500 - 2,000 pairs in Florida

Supplemental nest platforms readily acceptedSupplemental nest platforms readily accepted

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River otterRiver otter

Long, slender body, head is broad and flattenedLong, slender body, head is broad and flattened

Stiff whiskers around nose and snoutStiff whiskers around nose and snout

Long muscular tail, legs short and stoutLong muscular tail, legs short and stout

Thick guard hair, oiled fur, webbed toesThick guard hair, oiled fur, webbed toes

Small rounded ears. Ears and nostrils closeSmall rounded ears. Ears and nostrils closeunder water. 5-14 kg. Amphibious.under water. 5-14 kg. Amphibious.

Habitat: almost every aquatic habitat inHabitat: almost every aquatic habitat inFlorida except the KeysFlorida except the KeysDens: bank burrows, under roots of tree, rockDens: bank burrows, under roots of tree, rockpiles; both permanent and temporary nestspiles; both permanent and temporary nests

Den has underwater entrance with tunnel toDen has underwater entrance with tunnel tonest chambernest chamber

•• Breed once/yr: late summer or fall in FLBreed once/yr: late summer or fall in FL

•• Delayed implantation: gestation may last aDelayed implantation: gestation may last ayear, with 2 month pregnancyyear, with 2 month pregnancy

•• Litter size: 1-6, but 2-3 Litter size: 1-6, but 2-3 yg yg commoncommon

•• Post-partum estrusPost-partum estrus

•• Young fully furred, but helpless, at birthYoung fully furred, but helpless, at birth

•• Depend on mother for about 1 yearDepend on mother for about 1 year

Otters: unusually high metabolic rateOtters: unusually high metabolic rate

Water rapidly conducts heat away from bodyWater rapidly conducts heat away from body

Creates high-energy demands: depending onCreates high-energy demands: depending onwater temperature, individual may need towater temperature, individual may need toeat 15% of body weight/day in fisheat 15% of body weight/day in fish

Vulnerable to changes in prey availabilityVulnerable to changes in prey availability

Skillful swimmersSkillful swimmers

Hunting forays: 3-5 hours/night,Hunting forays: 3-5 hours/night,

Females with young: 8 hours/nightFemales with young: 8 hours/nighthuntinghunting

Diet of fish, crayfish, frogs, crabs,Diet of fish, crayfish, frogs, crabs,turtles, bird eggs, snakes, smallturtles, bird eggs, snakes, smallmammalsmammals

Otters: social animalsOtters: social animals

Vocal repertoire is large (chirps, whistles)Vocal repertoire is large (chirps, whistles)

Densities in good habitat: 1 otter per 3-5Densities in good habitat: 1 otter per 3-5mile of waterwaymile of waterway

MustelidaeMustelidae: strong musk glands in anal: strong musk glands in analregion. Common scent mark: fecesregion. Common scent mark: feces((spraintspraint) left at conspicuous points along) left at conspicuous points alongriver bank.river bank.

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Fur is valuable: harvestedFur is valuable: harvested

Status in Florida is not well knownStatus in Florida is not well known

Vulnerability: loss of wetland habitatsVulnerability: loss of wetland habitats

DonDon’’t cope well with vehicles: t cope well with vehicles: roadkillsroadkills

Cooter Cooter laying eggs: 3-holeslaying eggs: 3-holes

Highly aquatic: float in open water or inHighly aquatic: float in open water or inemergent vegetationemergent vegetation

Gigged by humans at night for frog legsGigged by humans at night for frog legs

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Common snapperCommon snapper

Alligator snapperAlligator snapper

Alligator snapping turtleAlligator snapping turtle

Worm-like projection on tongueWorm-like projection on tongue

Largest freshwaterLargest freshwaterturtle in the world.turtle in the world.Record: 236 lbRecord: 236 lb

Carapace: 31.5 inCarapace: 31.5 in

Diet:Diet: fish, frogs, snakes, clams, crayfish, fish, frogs, snakes, clams, crayfish,other turtles, and carrion.other turtles, and carrion.

Clutch: 8-52 eggs Incubation: 100-140 daysClutch: 8-52 eggs Incubation: 100-140 days

Sexual maturity: 11-13 yearsSexual maturity: 11-13 years