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By Michael A. Kallok

you ever watched a loon dive into a lake or a heronwalkinginshallowwateralongshore?Perhapsyou’vegazedupatanospreysoaringoverthewater.Alongariver,youmighthavecaughtaglimpseofariverotter.

Whatweretheseanimalsdoing?Theywereprobablyfishing.Likepeoplewhofish,thesewildanglersknowMinnesota’slakesandriversaregoodplacestofish.Theyareallreallygoodatfind-ingandcatchingfish.

Whenyougofishing,youuseafishingpoleorarodandreel. Minnesota’s wild anglers rely on their natural abilitiesand adapted traits such as sharp talons and bills to catch ameal.Somecanswimfast,usingwebbedfeet.Somecansoarthroughtheairanddivewithincrediblespeed.Someprefertofishalone,andothersworkwellasateam.

Wherever fish live, chances are good that Minnesota’swildanglersarenearby.

Meet seven Minnesota critters that dive after, scoop up, stalk, ambush, and chase fish for breakfast, lunch, and dinner.

Photography by Joe Rossi

Minnesota’s

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Common Loon (Gavia immer)Minnesota’s state bird, the commonloon, leaves its winter home along theAtlantic Ocean or Gulf of Mexico andfliestoMinnesotainspringafterlakeicemelts.Whenamale loonarrivesathissummerlake,hebeginsfishing.Hedivesdeep and swims fast to catch bluegills,perch,andothersmallfish.Onedaythemaleloon’smatejoinshim.Inthenorth-

ernlakewherethepairnests,theadultloonsspendmostoftheirtimelookingforsmallfishinshallowwater.

Hunt and Chase. Tohuntforperch,a favorite meal, the loon swims alongwith its eyes just below the surface.Whenitspotsaschooloffish,theloondivesandchasesthefish.

Theloon’sgiantwebbedfeetareway

backonitsbody—likeanoutboardmo-toronthebackofaboat.Theloonkicksbothofitsbigfeetatthesametimetopropelitsstreamlinedbodybeneaththewater.Toturnquickly,itusesitstaillikearudderandsticksonefootouttothesidewhilekickingwiththeother.

Thoughloonshavebeenobservedflyingasfastas90milesperhour,nooneisquitesurehowfastalooncanswim.Buttocatchafish,aloonmustswimfasterthanOlym-picchampionswimmerMichaelPhelps.

Float and Dive. Likeasubmarine,aloonadjustsitsbuoyancy,orabilitytofloat,bytakinginorreleasingair.Whenaloonbreathesin,airgoesthroughitslungsandinto stretchy membranes called air sacs.Whentheairsacsarefull,theloonswimshighinthewater.Whenreadytodiveforameal,theloonquicklyexhalestheair.

Mostbirdshavehollowbones.Aloon’sbonesarehollow,too,butthickerandwithlessairinside.Thishelpsloonsdivequicklybecausetheyareheavierandlessbuoyant.Loonscandivedeep.InwinteringareasintheGulfofMexico,theycandiveasdeep

as200feet.InMinnesota,smallperchandsunfisharemostabundantinshallowwa-ter.Loonsusuallystayunderwaterforlessthan a minute, but they can hold theirbreathforaslongas10minutes.

Catch and Eat.Whenaloongetsclosetoafish,itthrustsitsheadforwardandgrabsthefishinitsbill.Tiny,hookedteeth,calleddenticals,ontheloon’stongueandroofofthemouthhooktheslipperyfish.The loon swallows thewholefish,headfirst—usuallywhilestillunderwater.Eachdayanadultlooneatsabout2poundsoffish—that’sabout50smallperch.

Feed the Chicks. The parent loongrabs small fish, aquatic insects, or am-phibianssuchasfrogsanddeliverstheminitsscissorlikebilltofeeditsyoungatthesurface.A1-day-oldloonchickcanswim.Youngloonsrelyontheirparentsforfoodforabouttwomonths,buttwodaysafterhatching,loonchicksbeginpeeringintothewaterandchasingminnows.

Surf

ace Divers

Loons and pelicans are known as surface

divers. When they see or feel fish as

they swim upon the water’s surface, they

dive after or scoop up the fish.

A loon prepares to deliver a minnow to its chicks.

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Great Blue Heron (Ardea herodias)Standingastallas4½feet,thegreatblueheronisthelargestheronspeciesinNorthAmerica.Lookforitalongtheshoresoflakesandslow-movingrivers.Onceinawhile, you might see one in grasslandshuntingforgrasshoppersormice.

Quiet While Fishing.Stealthisthegreatblueheron’sadvantageforcatch-ingfish.Withitslong,skinnylegs,itcansilentlystalkthroughtheshallowsor stand perfectly still, waiting for afish to swim by. Sometimes a heronwillfishfromadockoralogdriftinglikeaboatonthewater.Becausetheheron’seyesarewell-adaptedforsee-inginthedark,itcanfishatnightaswellasduringtheday.

Eat the Catch. When a great blueheron spots a fish, it rapidly thrustsits long,pointybill intothewatertoseize itsprize.Notapickyeater, theheronwilleatanyfishnotmuchlon-gerthan12inches.Ifitcatchesaspinyfish,suchasaperchorbullhead,theheronwillsometimesshakeorspearthefishwithitsbilltoforcethefishtorelaxitsspinessotheheroncanmoreeasilyswallowit.

Dinner Bill.Foraboutamonthafterhatching,greatblueheronchicksstayinthenestandeatregurgitatedfishfroma parent’s bill. By 3 months old, theyleavethenest.Atfirsttheyareclumsyatflyingandnotverygoodatfishing,sotheirparentsmustcareforthemforafewmoreweeks.

Great Egret (Ardea alba)EgretsbeginarrivinginMinnesotainAprilandnestinthesoutherntwo-thirdsofthestatenearlakesandsmallrivers.Theynestintreesincolonies,calledrookeries,withtwoneststoseveralhundrednests.

Capturing Meals.Like thegreatblueheron,thegreategrethuntsforsmallfishby walking slowly or standing very stilland waiting. Sometimes it stirs up thebottom with its feet to uncover aquaticinsectsorcrustaceanstoeat.Ortheegretmight fly low over water, fluttering itswingstoherdfishintoanareawheretheycanbeeasilycaught.Sometimesoneegretwillstealamealfromanotheregret.

Learning to Fish. An egret parentfeedschicksregurgitatedfishfromitsbill.Youngegretsbegintofishforthemselvesaround 2 months of age. Juvenile greategrets don’t walk and hunt as carefullyasadultgreategretsdo.Andtheydonotcatchfishasoftenasadults.Butastheygrowup,theylearntowalkmorecarefullyandgetbetteratfishingforaliving.

Wad

ing Birds

Herons and egrets do their fishing

in shallow water by wading silently on their tall, skinny legs.

Green Heron (Butorides virescens)

Weighing an average of ½ pound, the green heron is much smaller than the great blue heron, but this wading bird is a fishing superstar. The green heron stalks fish in the shallows and dives from the air to grab fish with its bill. This wild angler also does something truly remarkable: It uses bait. The green heron, one of only a few tool-using birds in the world, tosses bugs, twigs, bread crumbs, litter, or other small items on the water to lure a fish near the surface, where the bird can easily grab it.

A great blue heron spears a hefty bullhead, which was swimming in shallow water near shore.

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Bald Eagle (Haliaeetus leucocephalus)Our national symbol, the bald eagle,soarsoverwaterlookingforanopportu-nitytogetameal.Thisopportunistic for-agerprefersfishbutalsoeatsmammals,reptiles,andotherbirds.Watchforbaldeaglesyear-roundnearopenwater.

Grabbing a Meal.Tofindfishorotherliveprey,aneagleglidesoverhead.When

itspotsamealwithitskeeneyes,itsud-denlyswoopsinandgrabsitwithoneorbothfeet.Itcarries itspreytoanearbytree,perchesonabranch,anddevoursit.Ifthefishisbig,theeaglemighteatitscatchontheground.Ifthecatchissmall,theeaglecansnackonitintheair.

Fish Thieves.Eagleseatalotoffish,butinsteadof livefish, theyofteneatdeadfish. Because of its imposing size and

fiercedemeanor,aneaglecansometimesstealfishfromasmaller,moresuccessfulwildangler,suchasaheronoranosprey.

Trial and Error.Youngeaglesleavethenestwhen2to3monthsold.Forthefirstfew weeks, these fledglings still dependon their parents for food. Young eagleslearntohuntforfishbytrialanderror.Meanwhile,theyfeedmostlyondeadfishtheyfindfloatingorwasheduponshore.

Osprey (Pandion haliaetus)Becauseospreysdon’teatmuchelsebutfish,theymusthaveaccesstoopenwa-ter.ComeMarch,asicemeltsonMin-nesota’s lakes and rivers, they returnfromasfarawayasSouthAmerica.

Ospreysfishforwhateverhappenstobeinshallowwaterornearthesurface.That might be sunfish, suckers, bull-heads,gizzardshad,ortrout.

Feet First. An osprey hunts from itsperchnearthewater.Oritsoarshighoverthewaterinsearchofschoolingfishnearthesurface.Tocatchfast-movingfishnearthe surface, theospreymakesagradualdive,likeaplanecominginforalanding.

Tograbafishswimmingasdeepas3feet,the osprey makes a steep dive, crashingstraightdown likea rock, feetfirst.Theosprey’slargefeethavelongtalonsandareversibletoethatworkslikeathumbtohelpholdslipperycatches.

Fishing Expert. When the fishing iseasy,researchershavefoundthatforevery10divesanospreymakes,itwillcatchasmanyassevenfish.Thesefishingprofes-sionalsofthebirdworldrarelyscavengeondeadordyingfish.Usingtheirpow-erful wings, ospreys can easily haul a2-poundfishfromthesurfaceofthewa-ter.Afteradive,theospreytwistsitsentirebodybackandforthintheairlikeadogshakingoffwater.Thenitheadsbacktoitsperchornesttochowdown.

Born to Fish.Ospreysusuallytaketheirfirst flight sometime before they turn 2monthsold.Researchersstudyingospreysin Florida observed fledglings trying tocatchfishfivedaysaftertakingtheirfirstflight.Whilelearningtofish,theydependontheirparentsforfood.

Aeri

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Eagles and osprey search for fish from the

air or from a perch high up in a tree. When

they spot a meal, they quickly descend

and grab it with razor-sharp talons, curved

like fishhooks to help hold slippery prey.

A bald eagle grabs a gizzard shad from the Mississippi River.

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North American River Otter (Lontra canadensis)The river otter, a full-time resident ofMinnesota, fishes year-round in rivers,lakes,andwetlands.Whilefishingbelowice,theriverottercanholditsbreathaslongaseightminutes.Tocatchabreath,itpopsupthroughaniceholeoraplacewhere river current has kept the wateropen.Otterssometimesappearplayfulastheyrollinthegrassorslidedownsnow-coveredhillsontheirsilkyfur.

Underwater Pursuit. This memberof the weasel family prefers to hunt atnight.Paddlingitswebbedfeetandflex-ing its long body and strong tail, this

powerful swimmer pursues its prey. Ithas excellent underwater vision. Theriverottercanalsolocatefishinmurkywater, thanks to vibrissae, sensitivewhiskersnearitsnostrilsthathelpdetectvibrationsmadebyswimmingfish.Theotter’s oily fur repels water. Its nostrilsandearsclosewhen itdives.Theriverotter catches a fish with its teeth andusesitsfrontpawstoholdthefishwhileeatingit.

Waterfront Living.Riverottersliveindens, which are usually natural hollowsalongthebanksoflakesandrivers.Whilemostoftheirdietisfish,theyalsodineoncrayfish,amphibians,andeventurtles.

Riverottersarealsorightathomeonland.Theyrunandboundwellandwon’tpassupamealofmiceorsmallbirds.

Hard-Working Mothers. When itcomestoraisingyoungotters,themoth-erotterdoesallthework.Givingbirthtolittersofonetosixyoung,thefemaleot-terfeedstheminthedenforabouttwomonths.Whenthekitsareoldenough,themotherotter leads themoutof thedenfortheirfirstswimminglesson.Be-ing naturally built for swimming, the

young otters quickly get the hang of itandbeginfishingontheirown.

Learn from Watching Wild AnglersYou can learn a lot about fishing fromwatching and listening to experiencedanglers.YoucanalsolearnbyobservingandaskingquestionsaboutthebehaviorofMinnesota’swildanglers.Doyoueverwonder why you always see a loon atyourfavoritefishingspot?Canyouwalkquietlyalongtheshorelikeawadingbird?Areyoupatientlikeaneagle?nV

Fish

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ing Furbearers

Scavengers such as raccoons, skunks,

and black bears eat fish when they find

them. Mink have the ability to pursue and

catch live fish, but the best of all fishing

mammals in Minnesota is the river otter.River otters eat a variety of fish, including pumpkinseeds (opposite page) and bullheads (this page). They also dine on crayfish, turtles, and frogs.

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A Note to TeachersFind links to teachers guides to this and other stories online at www.mndnr.gov/young_naturalists.

* www.mndnr.gov/magazine Watch a pair of river otters diving for fish on a Minnesota lake.