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Dedicated to Sharing Information About Water Management and the Florida LAKEWATCH Program Volume 40 (2007)

Secure the Legacy-A Fundraising Update The most difficult task anyorganization can undertake is theraising of private funds. This is trueno matter how much money seemsto be out there or how good thecause. Success, however, isachieved through commitment,making the personal contacts, andpersistence! LAKEWATCH volunteers havedemonstrated all three of thesetraits of success over the past fewmonths, resulting in the raisingof over $44,000. Much of thismoney has come through thepurchase of LAKEWATCH Legacybricks. As the Christmas holidayapproaches, consider donating a

brick for each of your loved-onesor someone else that is special! Substantial funds have beenraised through soda/candy/chipsales in the name of FloridaLAKEWATCH or the highly awardedyouth education program, Fishingfor Success. Other funds are nowarriving from donations for theLAKEWATCH calendar. Thecalendar is an excellent way youcan help to spread the word aboutLAKEWATCH to fellow Floridians aswell as friends who live outsideFlorida. Besides, it is a beautifulproduct that will grace any wall! Other funds come toLAKEWATCH from our friends who

have contributed to building the“Home” for LAKEWATCH andFishing for Success. An anonymousdonor just sent a contribution of$10,000! The campaign for aLAKEWATCH HOME is makinggreat progress given that “word ofmouth” has been the primarymeans of communication. Radioand TV shows have been releasedin parts of Florida as well as newsarticles in statewide publications.Success, however, will only beachieved with each of you makingthe personal contacts andpersisting with the request forhelp. Available funds are close to$100,000 given past efforts andfuture pledges, but the fund-raisingcommittee established a goal of$1,000,000 so the LAKEWATCHteam has a long way to go. TheLAKEWATCH advantage is that theState of Florida will match eachdollar raised. If each of you willreach out to your neighbors andothers using our lakes and coastalwaters, the pooling of many smallcontributions will get the hard taskof funding a LAKEWATCH HOMEdone!

FloridaLAKEWATCH

Pictures of the current LAKEWATCH facilities and a diagram of the proposed newbuilding.

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An aerial view of Red Tide moving into a southwest Florida beach.

RED TIDE!

Red tide, sometimes referred to asharmful algal blooms (HAB), occurswhen toxic, microscopic algae inseawater proliferate to higher-than-normal concentrations known asblooms, often discoloring the waterred, brown, green, or yellow. Whilemore than 40 species of toxic microalgae live in the Gulf of Mexico, themost common species is calledKarenia brevis also known as theFlorida red tide organism. The Florida red tide organism wasidentified back in 1947, but anecdotalreports of the effects of red tide inthe Gulf of Mexico date back to the1530’s. Florida red tides occur in theGulf of Mexico almost every year,generally in the late summer or earlyautumn. They are most common offthe central and southwestern coastsof Florida between Clearwater andSanibel Island, but they may occuranywhere in the gulf. They alsooccur, but are less common, along

brevetoxins that is capable of killingfish, birds, and other marine animals.Bottom-dwellers such as groupersand grunts are usually the first fish todie in a Florida red tide, althoughmost fish are probably susceptible.Mortality, in terms of numbers killedand species affected, can be severeand is dependent upon factors suchas bloom density and the length oftime animals are exposed to thetoxins. Brevetoxins may also causehealth problems in humans. Thetoxins accumulate in shellfish that arefilter feeders, such as oysters, clams,and coquinas, and may reach levelscapable of causing neurotoxicshellfish poisoning (NSP) wheningested. NSP is a temporary illnesscharacterized by gastrointestinal andneurological distress. Symptomsinclude nausea and diarrhea;

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the southeastern Atlantic coast as farnorth as North Carolina. Most bloomslast three to five months and mayaffect hundreds of square miles,however, blooms can continuesporadically for as long as 18 monthsand may affect thousands of squaremiles! Karenia brevis is a commonphotosynthetic dinoflagellate (a typeof free floating algae) found year-round throughout the Gulf of Mexico.It has two whip-like appendages, orflagella, that propel and direct itthrough the water. In Florida watersK. brevis thrives in high-salinityareas, but it can tolerate a widerange of salinities and temperaturescommon to the Gulf of Mexico. Thisspecies is able to out-compete otherphytoplankton (free floating algae)and forms nearly monospecificblooms. Karenia brevis produces

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A victim of the Red Tide in Northwest Florida (October 2007).

dizziness; muscular aches; andtingling and numbness in the tongue,lips, throat, and extremities.Symptoms of NSP usually appearwithin a few hours of eatingcontaminated shellfish and disappearwithin a few days. Brevetoxins can also irritate eyesand respiratory systems when thetoxins become airborne in sea spray;the irritation disappears once aperson is no longer exposed. Otherpublic health effects caused by redtides include puncture wounds fromspines when beaches are littered withdead fish and, rarely, contactdermatitis from exposure tobrevetoxins in seawater. Florida red tides have economicimpacts as well. Tourist communitieslose millions of dollars when deadfish wash up on beaches orbeachgoers experience eye andrespiratory irritation. Shellfish-harvesting businesses lose incomewhen shellfish beds must be closedbecause of Karenia brevis blooms.Even tourism, recreational activities,and other businesses not actually atthe bloom site may be adverselyaffected. Although it is hard tocalculate actual dollars lost, a studyof three red tide blooms that occurredin the 1970s and 1980s estimatedlosses from each event at between

$15 million and $25 million dollars. Prior to the early 1970’s, Floridared tides were believed to originateinshore because discolored water,fish kills, and respiratory irritationwere most often observed firstaround passes and barrier islands.Later review of the historical datacompiled from research cruisesshowed that Florida red tides actuallybegin in nutrient-poor water offshore.Resting populations of K. brevis arebelieved to exist in the water columnor sediments in specific areas on the

west Florida continental shelf. Biologists have documented theoccurrence and abundance of the K.brevis organism for more than 50years. Most sampling occurred after abloom had already begun asevidenced by reports of dead fish,discolored water, or respiratoryirritation. Data collected from suchresponse-oriented monitoring isincomplete and limited because bythen it would be too late to study theinitiation and growth phases of thebloom. Bloom detection usingsatellite technology and color imagerybegan in the 1970’s. In the satelliteimages, different concentrations ofchlorophyll are seen as different colordensities, and the color densities arecorrelated with cell densities of K.brevis. Satellites can be used to tracksurface blooms as they move, butthey cannot yet detect bloomdevelopment or subsurface blooms. Several research programs havebeen used to study the possibility ofmitigating the effects of red tidesthrough prediction or advancedwarning. One such project is thefederally funded Ecology andOceanography of Harmful AlgalBlooms (ECOHAB) program.ECOHAB investigators in Floridacollect data from research cruisesand from moored buoys to studythe biology of K. brevis and its

Red Tide can affect us economically as well as ecologically

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movement in response toenvironmental variables such astemperature, salinity, and currentsmonitored on the continental shelf.Physical, chemical, and biologicaldata are used to model andpredict bloom initiation, growth,maintenance, and dissipation ortermination; to evaluate life-cycleprocesses; and to study thetransport and eventual fate of thebrevetoxins. A pilot project called theHarmful Algal BloomS ObservingSystem (HABSOS) is anotherfederally funded program tocollect from federal, state, andacademic laboratories all availabledata on red tide events and tocompile the information in acentral, accessible, continuallyupdated repository. Such adatabase will give investigatorsthe ability to study events as theyoccur and perhaps forecast themovement and probable effects ofa bloom. The Florida HarmfulAlgal Bloom Task Force wasestablished in 1997 to identifygaps in the data already collectedand to recommend additionalresearch and monitoring neededon Florida red tides and theirassociated effects. The TaskForce consists of representativesfrom federal agencies, state andlocal governments, watermanagement districts,universities, private laboratories,and a citizen-volunteerorganization. The volunteerprogram was established in 2000to help monitor the extensiveregion over which Florida red tidesmay occur. Volunteers collectwater samples from establishedoffshore transects in a networkextending from Pensacola to theFlorida Keys and send them to theFlorida Fish and Wildlife ResearchInstitute (FWRI) for analysis. Red tides are a part ofFlorida’s history and will mostlikely remain a part of its future.Scientists continually strive tolearn more about factors affectingthe growth and intensity of K.brevis blooms. Although the

biology of the organism and the rolethat red tides play in the dynamics ofthe Gulf of Mexico ecosystem are stillnot fully understood, predictive twoand three-dimensional models arebeing developed and tested. Datagenerated through traditional

environmental sampling andmonitoring, in combination with datagenerated through newer approachessuch as remote sensing andmodeling, may give us the ability toforecast red tide events and mitigate,or even eliminate, their effects.

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Dead fish from Red Tide with an inset of a microscopic look at Karenia brevis.

The information used to compile this article came from theFlorida Fish and Wildlife Conservation Commission’s Fish

and Wildlife Research Institute.

For more information on Red Tide and the current status of Red tide inFlorida visit:

http://research.myfwc.com/features/

and click on “Red Tide”

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Making Cities a Greener Place to Live- The Orlando Example

It’s always about leadership. Orlando, a city of vision, knows this. That’s why the City of Orlando is asking localbusiness leaders to join its innovative Orlando Green Business Program. The program encourages business owners tobecome partners in protecting Orlando’s waterways.

The program can be applied to a variety of businesses, but during the initial phase the city has developed specificprograms for restaurants, vehicle maintenance facilities and lawn care/maintenance specialists. In the future, theOrlando Green Business Program will be expanded to other types of businesses.

Specifically, the Orlando Green Business Program arms business owners with the knowledge and tools they need toreduce their pollution in stormwater runoff. Although the program is free for local businesses, there are several stepsto becoming an Orlando Green Business Program member. They are:

• Participate in an on-site stormwater review by City of Orlando staff• Select a representative to be responsible for implementing and following the Green Business guidelines, as well

as act as a liaison between the participating company and Orlando’s Green Business Coordinator• Review the booklet, Orlando’s Lakes: The City Beautiful’s Natural Connection to understand the vital connection

between what we do and what happens to our waters as a result• Follow and post Best Management Practices throughout facilities• Spread the word by requiring employees to participate in trainings/presentations provided by city staff• Have all pertinent employees sign pledges stating they will continue their commitment to reduce the pollutant

load to our lakes and streams

Once businesses have completed all of the program requirements, they will receive:• Free publicity on the city’s Web site and in a variety of publications featuring articles about the Orlando Green

Business Program• Orlando Green Business certification• Promotional materials, such as posters and decals, to share with employees and customers• Recognition from Mayor Buddy Dyer

Small changes in the way we do business result in major benefits to our local lakes. Stormwater transports everythingin its path—trash, oil, grease, grass clippings, fertilizers and pesticides— into our waterways. Stormwater runoffimpacts our drinking water supplies, alters aquatic habitats and puts our unique quality of life at risk.We have more than 100 lakes in the City of Orlando, and by working together we can improve water quality in eachone.

I know I speak for everyone when I say we will miss Sky and all of the talents he brought to the LAKEWATCH program and thatwe wish him well on his new career path. Good luck Sky!!!!

Mark HoyerAssistant Director Florida LAKEWATCH

New Regional DutiesUntil a more permanent solution is determined, the remaining LAKEWATCH Coordinators will handle Sky’s Region from thePanhandle down through Citrus County as follows:Eric Schulz:Gadsden, Liberty, Franklin, Leon, Wakulla,Claude Brown:Jefferson, Madison, Taylor, Dixie, Levy and Citrus Counties.David Watson:Escambia, Santa Rosa, Okaloosa, Walton, Holmes, Washington, Bay, Gulf, Calhoun, and Jackson Counties.Dan Willis will take over the following counties from David Watson:Orange, Brevard and Indian River.

Collection Center Changes

Volunteer Bulletin Board

Notice to all FloridaLAKEWATCH samplers

Keep those samples flowing!

Please be sure to deliver all frozen water and chlorophyllsamples to your collection center as soon as possible. Thiswill enable us to prepare the annual data reports onschedule.

We’d also like to take this opportunity to thank you for yourhard work and dedication!

Sincerely,

The Florida LAKEWATCH Crew

Citrus CountyThere is a change in the collection center for Crystal River:

The collection center at Oyster’s Resturant hasbeen moved to the Crystal River Preserve StatePark.

The new contact information is:

Crystal River Preserve State Park3266 N Sailboat Ave.Crystal River, FL 34428352-563-0450

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An Update on the Largemouth Bass Stocking Project on Lake Griffin

Lake Griffin is a large 9,428 acrelake located in the Ocklawaha Riverbasin near Leesburg, Florida. In 1999,the Florida Fish and WildlifeConservation Commission (FWC)reported that the sport fish populationand fishery of Lake Griffin was at ahistorical low point. The averagebiomass of Florida largemouth bass(Micropterus salmoides floridanus)per unit effort of sampling in thevegetated zone of Lake Griffin was81% lower when compared to theaverage largemouth bass biomasssampled in 1986. During fishsampling in 1999 and 2000, the FWCfound an extremely low density oflargemouth bass and documentedvery few small, young of the yearjuveniles, indicating a possibleproblem with reproduction. Consequently, the FloridaLAKEWATCH program (FLW)proposed a research/demonstrationproject to transfer substantial numbersof largemouth bass greater than 8inches in total length into LakeGriffin with the goal of restoring theeconomic vitality of Lake Griffin’slargemouth bass fishery. Three mainobjectives of this stocking programwere to: 1) mitigate damage done tothe largemouth bass fishery whilewaiting for ongoing environmentalrestoration programs to improvelargemouth bass habitat in LakeGriffin, 2) determine if sufficientnumbers of largemouth bass greaterthan 8 inches in length could becollected from private waters andsuccessfully transferred to LakeGriffin, and 3) determine if thestocking program could contribute tothe economic vitality of LakeGriffin’s largemouth bass fishery. This project was funded andsupported by the Harris Chain ofLakes Restoration Council and theLake County Water Authority(LCWA). In 2005, the LCWAcontracted with FLW to implementthe transfer of approximately 4,000largemouth bass into Lake Griffin.The LCWA then evaluated the project

and considered it to be successful, sothe project was funded again in 2006and 2007. In 2007, a total of 4,666largemouth bass were transferred intoLake Griffin. Approximately 58% ofthe largemouth bass collected fortransport were between 8 and 12inches in length. The remaining 42%of the largemouth bass stocked were12 inches or greater in length andweighed from 2.5 to 9.3 pounds.Since 2005, the total number oflargemouth bass stocked into LakeGriffin that were greater than eightinches was 13,933, with 7,024 ofthose fish measuring over 12 inchesin length. About 50% of the bass stockedinto Lake Griffin were fitted withorange plastic tags that werenumbered and printed with the toll-free telephone number for the FloridaLAKEWATCH program. These tagshelped FLW monitor the progress ofthe project. The FLW and FWC assessed thepotential impact to the resident basspopulation of Lake Griffin of

Florida LAKEWATCH personnel Dan Willis places an orange tag into a largemouthbass before stocking the fish into Lake Griffin.

stocking almost 14,000 largemouthbass from 2005 through 2007. FloridaLAKEWATCH recaptured a total of87 tagged fish that were stocked in2007 and 36 tagged fish that werestocked in 2005and/or 2006. Florida LAKEWATCHcaptured tagged largemouth bass in68% of their lake-wide samplingsites. The Florida Fish and WildlifeConservation Commission captured22 tagged fish that were stocked in2007 and 5 tagged fish that werestocked in 2005 and/or 2006 duringtheir sampling of Lake Griffin.Approximately 10% to 13% of thefish collected by FLW and FWC weretagged fish. The fact that stocked fishcomprised 10% to 13% of total fishcollected indicated that FLW hadachieved a temporary increase in thenumber of largemouth bass availableto anglers in Lake Griffin. When undertaking a stockingprogram of larger-sized fish, theultimate question that arises is thecost/benefit to the funding agency.

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Although this project was notdesigned to directly measureeconomic impacts, the informationthat was collected could provide somelimited insights for the LCWA.According to the 2001 NationalSurvey of Fishing, Hunting, andWildlife-Associated Recreationpublished by the U.S. Department ofInterior in 2001, Florida anglers spentan average of $1,341 per angler peryear on fishing. This means that LakeGriffin anglers could have spentbetween $858,240 and $1,716,480 in2007 alone. Since the beginning ofthe project in 2005, it is possible thatfrom $4,800,780 to $9,601,560 couldhave been spent by anglers fishing inLake Griffin. A more conservative way ofexamining cost/benefit relationshipsis to calculate the replacement orrecreational value assigned by theState of Florida according to theFlorida Administrative Code 62-11.001. The replacement value in2006 dollars for largemouth basstransferred in 2007 would be $68,341and the recreational replacementvalue would be $74,694. SinceDecember 2004, the total replacementvalue and recreational replacementvalues would be $230,692 and$352,843, respectively. Thesefindings suggest that the largemouth

bass stocking program has generatedconsiderable economic activity in thelocal community. However, absolutedollar estimates can be obtained onlywhen a comprehensive economicanalysis of the sport fishery iscompleted. This research/demonstrationproject showed that considerablenumbers of larger-sized Floridalargemouth bass could be collectedfrom private waters during areasonable time window (determinedby water temperature) andsuccessfully transported to LakeGriffin. The underlying goal was toassist in restoring the economicvitality of Lake Griffin’s largemouthbass fishery. Information obtainedfrom angler reports, as well as

reports from local fish camp owners,revealed that anglers fishing in LakeGriffin and other lakes of the HarrisChain were catching a substantialnumber of the transferredlargemouth bass and were spendingtheir money in the Harris Chain ofLakes area. It appears that theLCWA received an immediatereturn on their investment andeconomic returns should continueover the next few years given thepractice of catch and release bymost largemouth bass anglers.However, the magnitude andduration of economic returns to thecommunity will require that anglersmaintain an optimistic attitude aboutthe potential for fishing success atLake Griffin.

An Update on the Largemouth Bass Stocking Project on Lake Griffin (continued from page 7)

A largemouth bass with inserted orange tagready to be stocked into Lake Griffin.

Florida LAKEWATCH personnel Darren Pecora releases a tagged largemouthbass into Lake Griffin.

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A drought is an extended period ofmonths or years when a region notes adeficiency in its water supply. Generallythis occurs when a region consistentlyreceives below average rainfall.According to the October 2007 droughtsummary provided by the FloridaDepartment of Environmental Protection(FDEP), the statewide drought conditionshave improved since this summer butFDEP still has concerns about theupcoming historically dry winter season.

One of the vessels was 50 to 60 feet long.Archaeologists have left most of the findsin the lake but did remove a few items. Drought can affect Florida’s coastalareas as well. Because of record low lakelevels in Lake Okeechobee, the SFWMDhas released little or no water into theCaloosahatchee River this year. This hasreduced the flow of murky fresh waterinto the river and eventually into SanCarlos Bay at Ft. Myers allowing greaterlight penetration and higher salinities inthe estuaries associated with the river.Just to the south of San Carlos Bay,

During the summermost of Floridaexperienced droughtconditions, but as weapproach winter itappears that onlynorthwest Florida isexperiencing severedrought conditions.According to theNorthwest FloridaWater ManagementDistrict the averagerainfall across thedistrict (Tallahassee toPensacola) was 22inches below normal asof October 19, 2007.As we reported inVolume 18 of theFlorida LAKEWATCHnewsletter, there aresome benefits ofdrought. This summer,the South Florida Water ManagementDistrict (SFWMD) took advantage of arecord low lake level in LakeOkeechobee to remove muck from thelake. The District’s governing boardapproved more than 11 million dollars toremove a total of 3.8 million cubic yardsof muck. The District conducted a similarmuck removal project during the 2001drought. Also in Lake Okeechobeearchaeological benefits of the droughtrecently surfaced. The exposed lakebottom yielded thousands of pieces of

FDEP scientist working in the Estero BayAquatic Preserve noticed expansion(from 5-25% coverage to 50-75%coverage) in seagrass coverage versustwo years earlier when the effects ofincreased water releases from LakeOkeechobee due to repeated hurricanescaused significant decreases in seagrasscoverage. The FDEP scientists reportedthat the mouth of the Caloosahatchee hasseen the greatest increase of seagrass bedcoverage in the area.

Juniper Lake in Walton County after several months of severe drought in the Floridapanhandle.

pottery, five boats and a number ofhuman bone fragments. Most of thebones were extremely fragmented andwere estimated to be 500 to 1000 yearsold. Because of the estimated age of thefragments the state has alerted theSeminole and Miccosukee tribes of thebones. The five boats were considerablyyounger and included a steam powereddredge, possibly used to dig canals, asteamship, a wooden motorized canoeand a catfish boat from the early 1900’s .

Homeowners may intentionally

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Drought! Here We Go Again.

During thedrought of 1999-2001, theDepartment ofFisheries andAquatic Sciences(FAS) at theUniversity of Floridawas conducting astudy of thephysical, chemicaland vegetativecharacteristics offive gulf coastrivers. FASdiscovered thatduring the time ofdrought and lowwater in theChassahowitzka andHomosassa Rivers,the submersedaquatic vegetation inthe rivers decreased,

especially in the lower reaches of therivers. They also noticed that duringthe drought the submersed plants inthe lower reaches of the riversswitched from freshwater species tomore saline tolerant ones. Duringsevere drought periods saltwaterintrusion in coastal areas can affectcoastal river ecosystems. While drought can certainly affectaquatic ecosystems here in Florida inboth positive and negative ways,

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In 2001 LAKEWATCH published an article in our Florida LAKEWATCH newsletter (Vol. 18) onthe bright side of Florida’s drought. During that time the whole state was experiencing a severedrought. We thought that given the current drought conditions in parts of the state this year,we should revisit the effects of drought on aquatic ecosystems in Florida.

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So while the drought may temporarily cause problems and a change toFlorida waterbodies, our main message is this…don’t give up! It willrain again and water levels will eventually return to “normal.” Whenthat does happen, LAKEWATCH volunteers will have a chance of alifetime to participate in the collection of some extremely importantwater chemistry data. So keep up the good work and stay tuned!

it is important to remember that thecycles of floods and droughts that Floridaexperiences is natural, normal andrecurring. According to the Florida Fishand Wildlife Conservation Commission(FWC); “Florida’s ecosystems aredependent on this cycle of drought andflood to maintain healthy fish andwildlife populations. The long-termbenefits of droughts and floods oftenexceed the short-term negative effects.”Some of the benefits listed by the FWCwere increased effectiveness of plannedhabitat enhancement projects,opportunities for improvement to boatramps, docks and seawalls, and increased

angling opportunities to fresh wateranglers as marine species are able totravel further up river in some riversystems. Some of the negative affectslisted were increased sinkholeformation resulting in lake drainage,increased stress on fish due to salinityincreases in tidal creeks and lowwater levels that can trap fish,resulting in fish kills from lowdissolved oxygen. Florida can also feel the effects ofdrought in other states. The State ofGeorgia’s attempt to press the Federalgovernment to temporarily lift theEndangered Species Act and reduce

the amount of water flowing fromLake Lanier (the source of Atlanta’sdrinking water) could affect Florida’secology and economy accordingGovernor Charlie Crist in a letter toPresident Bush earlier in November.This renewal of the tri-state waterwars resulted in Officials from theWhite House, the Department of theInterior and the U.S. Corps ofEngineers meeting with the governorsof Florida, Georgia and Alabama towork out a temporary plan for howthe three states would share themuch-reduced waters of Lake Lanier.

Drought! Here We Go Again! (continued from page 9)

Areas of exposed lakebed of Lake Okeechobee. The area is normally submerged, but is now dry because of a severe drought.

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Bryozoa are predominantly foundin salt-water habitats with 4000species listed as marine and only 50species restricted to freshwater. As agroup, they are often confused withtheir ecological analogs, the corals,but they are unrelated taxonomically.

All bryozoans are colonial withgrowth habits determined as afunction of water energy. The growthforms include encrusting and massiveor domal (blob-like) forms found inhigh-energy environments such asshallow lakes with a lot of windactivity and branching or erect formsfound in low energy environmentslike protected backwaters.

In Florida, the freshwater speciesare usually found in unpolluted andunsilted waters of shallow ponds,lakes, and streams. Bryozoa usuallyoccur where the light is dim as incolored waters. Colored or stainedwaters are often the result of theleaching of tannins and humic acidfrom plant material and soilssurrounding the waterbody.

The picture submitted by ourLAKEWATCH Volunteer on OakLake in Hamilton County is of ahealthy specimen of Bryozoa knownas Pectinatella magnifica. The colonyis gelatinous, firm, and slimy to thetouch. The inner mass is composedmostly of water and the surfaceappears to be divided into littlerosettes. Millions of individuals canform one colony. In each colony,different individuals assume differentfunctions: some gather food, othersare devoted to strengthening thecolony, and still others clean thecolony. Bryozoans have no bloodsystem as gaseous exchange occursacross the entire colonial surface.Massive colonies may exceed 2 feetin diameter, but typical sizes are 1foot or less. As you can see by thephoto this specimen is a champion!

All bryozoans are filter feeders.The bryozoan’s diet consistsprimarily of small microorganisms,including diatoms and otherunicellular algae. Studies have shownthat bryozoans can filterphytoplankton (microscopic

Bryozoa (Moss Animalcules) ----What is That?free-floating algae) less than 0.045mm in size (1/1800 of an inch) fromthe water column and that eachindividual in a colony can clear 8.8ml (almost 1/3 of an ounce) of waterper day. A large colony would act asa living bio-filter clearing severalgallons to several thousand gallons ofwater a day.

Bryozoa themselves are anelement in the diet of manyfreshwater invertebrates and somefish.

Bryozoans can reproducesexually and asexually. Asexualreproduction occurs by budding offnew individuals as the colony growsand is the main way colonies expand.Sometimes part of the colony breaksoff, but it can continue to grow andwill form a new colony.

All freshwater bryozoans arehermaphroditic, having both male andfemale sexes present in the colony. Aunique feature of freshwater Bryozoais the production of highly resistantstatoblasts. Statoblasts are anasexually produced encapsulated budof the freshwater bryozoans thatappears with the onset of hot weatherand functions mainly in tiding thespecies over unfavorable conditionssuch as droughts and drastic changes

in water quality and temperature.Statoblasts also aid in geographic

dissemination. There are reports thatstatoblasts occur in mud found on thefeet and feathers of waterfowl and thefur of mammals. In fact, somestatoblasts are capable of germinatingafter passing through the digestivetract of waterfowl, turtles, frogs,salamanders, and fish.

The lengths of the statoblastdormant period are highly variabledepending on the species, theindividual, temperature, and otherenvironmental conditions, but themajority over winter and germinatethe following spring.

Rising temperatures initiateactive budding in bryozoans and tosome degree sexual reproduction.Most American species attain theirgreatest abundance in the summerwhen the water temperature reaches23° C (72° F) or higher. Colonies ofPectinatella magnifica usually die offwhen the water temperature goesbelow 16° C (60° F).

A review of the literatureindicates large floating gelatinouscolonies of Pectinatella magnificacan clog the screens of water intakes

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A bryazoan (Pectinatella magnifica) collected by LAKEWATCH volunteer TomNeeley of Oak Lake in Hamilton County.

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This newsletter is generated by the Florida

LAKEWATCH program, within UF/IFAS’

Department of Fisheries and Aquatic Sciences.

Support for the LAKEWATCH program is provided

by the Florida Legislature, grants and donations. For

more information about LAKEWATCH, to inquire

about volunteer training sessions, or to submit

materials for inclusion in this publication, write to:

Florida LAKEWATCH

7922 NW 71st Street

Gainesville, FL 32653

or call

1-800-LAKEWATCH (800-525-3928)

(352) 392-4817E-mail: fl-lakewatch@ufl.eduhttp://lakewatch.ifas.ufl.edu/

All unsolicited articles, photographs, artwork or other

written material must include contributor’s name,

address and phone number. Opinions expressed are

solely those of the individual contributor and do not

necessarily reflect the opinion or policy of the Florida

LAKEWATCH program.

Department of Fisheries and Aquatic SciencesFlorida LAKEWATCH7922 NW 71st StreetGainesville, FL 32653

FloridaLAKEWATCH

environment to enjoy. Pectinatellamagnifica has been observed on threedark water lakes in the FloridaLAKEWATCH program: Oak/Hamilton, Holden Pond/Alachua, andLittle Orange/Alachua.

and grates of hydroelectric plants. Ifyour lake water is not used forirrigation or cooling power plantsthen Pectinatella magnifica shouldnot be a nuisance, just anothermarvelous curiosity of your lake

Pectinatella magnifica growing attached to a submersed surface.

Bryozoa (Moss Animalcules)----What is That? (Continued from page 11)

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