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Dedicated to Sharing Information About Water Management and the Florida LAKEWATCH Program Volume 42 (2008)
Toxic Algae: Should Floridians Be Worried?
Toxic algae are an issue of increasingconcern for scientists and communitymembers alike. Especially in Florida, wehear and see media headlines claiming thedangers and adverse effects caused bytoxic algae. The fear of these microscopicorganisms is ever present and escalating,therefore, gaining a better understandingand awareness of toxic algae will providethe average citizen with the ability todetermine if these claims are a cause forconcern.
When reading about toxic algae blooms,sometimes people are confused as towhether marine or freshwater algae areresponsible. Take for example theorganism that causes the dreaded Red Tidethat causes massive fish kills along our
Florida beaches. The dinoflagellate algaespecies that scientists have named Kareniabrevis can produce a toxin calledbrevetoxin. When these algae bloom inlarge numbers they are responsible forcausing the toxic conditions known as RedTide. While dinoflagellate algae are foundboth in freshwater and marine water, thedinoflagellates responsible for causing thered tide only occur in marine waters.
When examining toxins produced by algaein freshwater systems, the focus ofconcern should be directed to the type ofalgae known as blue-green algae orcyanobacteria. Blue-green algaepredominate in freshwater systems andgenerally proliferate in warmer waterswith high nutrient concentrations. Because
many of Florida’s freshwater systemsexhibit these characteristics, blue-greenalgae blooms have the potential to occurfrequently.
There are many species of cyanobacteriathat can contribute to these blooms, but theblue-green algae called Microcystisaeruginosa is one of the most common.Some strains of blue-green algae produce atoxin called microcystin. Microcystin is ahepatotoxin (or liver toxin) and may alsoact as a tumor promoter in studies
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FloridaLAKEWATCH
A microscopic view of Microcystis aeruginosa.
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completed in rats and mice. Reportedcases of animal sickness and death havebeen attributed to microcystin. Many ofthese cases involved cattle or dogs that hadingested water containing extremely highmicrocystin concentrations as a result ofintense algae blooms. Rare instances ofhuman deaths have occurred when patientsreceived contaminated water containinghigh microcystin concentrations duringtheir dialysis treatments.
In response to these microcystin studiesand reported cases, the World HealthOrganization (WHO) developedprovisional safety standards formicrocystin concentrations in water. TheWHO drinking water standard was set at 1µg/L and a recreational water contactstandard was set at 20 µg/L. Because thepossibility of adverse effects frommicrocystin exists, water samplescollected by Florida LAKEWATCHvolunteers were analyzed for microcystinconcentrations to identify potentialproblem lakes or areas of concern.
From January-December 2006, FloridaLAKEWATCH collected 862 individualwater samples from 187 Florida lakes thatwere analyzed for microcystin. Thesesamples were analyzed using an enzyme-linked immunosorbent assay known asELISA. An ELISA kit consisted of a platewith 98-wells and into each well the lakewater sample was loaded. After treatmentwith several different chemical processes,the absorbance of each water sample wasread with a microplate reader. From theabsorbance value, the microcystinconcentration was calculated. Thefollowing are three major findings fromthe study.
(1) Of a total of 862 water samples thatwere analyzed:
Only 7 % of the water samples exceededthe 1 µg/L World Health Organizationstandard established for drinking water.
Only 3 individual water samples (0.3%)exceeded the 20 µg/L World HealthOrganization standard established forrecreational water contact.
Therefore, microcystin does not seem topose a major threat to lake recreational
activities such as boating, fishing,swimming, and water skiing. However,concerns could arise if the lakes were usedfor drinking water sources.
(2) Water samples collected fromeutrophic and hypereutrophic lakestended to have higher microcystinconcentrations and were the only watersamples in this study that exceeded theWHO drinking water and recreationalwater contact standards.
All water samples were classified intotrophic states based on the amount ofbiological productivity as estimated using
chlorophyll concentration and the criteriaof Forsberg and Ryding (1980). Thefollowing four trophic state classificationsare based on chlorophyll concentration:oligotrophic < 3 µg/L, mesotrophic 3 - 7µg/L, eutrophic 7 - 40 µg/L, andhypereutrophic > 40 µg/L. The results areshown in Table 1.
The data show that as the trophic state ofthe water samples increases, thepercentage of water samples containingmicrocystin concentrations that meet orexceed the WHO drinking water standard(1 µg/L) and recreational water contactstandard (20 µg/L) increases as well.
A Microsystis aeruginosa bloom on the surface of a lake.
Table 1. Trophic states for the water samples analyzed for microcystinconcentration and percent of water samples that met or exceeded the WHOdrinking water standard (1 µg/L) and WHO recreational water contactstandard (20 µg/L).
Trophic state ofwater samples
analyzed
# of watersamples foreach trophic
state
% of water sampleswith microcystin
>1µg/L
% of watersamples withmicrocystin
>20µg/LOligotrophic 102 0% 0%Mesotrophic 221 0% 0%
Eutrophic 378 4% 0%Hypereutrophic 161 27% 2%
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In other words, eutrophic andhypereutrophic lakes have the potentialfor higher microcystin concentrations.Although some oligotrophic andmesotrophic lakes had water sampleswith detectable microcystinconcentrations (0.1 µg/L was thedetection limit), none of these lakes hadconcentrations that met or exceeded theWHO drinking water standard of > 1µg/L.
(3) In some hypereutrophic Floridalakes, microcystin concentrationsbegin increasing in late summer withthe highest concentrations occurringduring the months of Septemberthrough December.
At any time throughout the year in theeutrophic and hypereutrophic Floridalakes tested in this study, there was apotential for microcystin concentrationsthat were > 1 µg/L. However, starting inSeptember and going through December,microcystin concentrations in somehypereutrophic lakes increased with thehighest values (> 20 µg/L) occurringduring this time period.
Now that the data has been presented, we
pose the question “Is microcystincontamination the greatest threat to usersof Florida’s freshwaters?” Let’s think ofthe possibility versus the probability. Thepossibility is there because intense blue-green algae blooms will occur and couldpotentially create high microcystinconcentrations. However, based on
Dana Bigham, a graduate studentwith Florida LAKEWATCH at theUniversity of Florida, contributedthis article based on research shedid to fulfill the requirements for aMasters of Science Degree. If youhave any questions or concerns,please feel free to contact Danaat:
To learn more about microcystin, take a look at the book Toxic cyanobacteria in water: A guide to their publichealth consequences, monitoring, and management Edited by Ingrid Chorus and Jamie Bartram. This book isavailable from the Internet at the following link:
http://www.who.int/water_sanitation_health/resourcesquality/toxicyanbact/en/
the evidence the probability ofencountering high microcystinconcentrations in Florida lakes thatexceed the WHO recreational watercontact standard seems to be low, atleast based on the results of this studydone during 2006. To be on the safeside, remember that if a major algaebloom is observed or reported, it isprobably best to keep both humansand animals out of the water as aprecautionary measure until thebloom subsides.
An ELISA plate ready for analysis.
An ELISA plate during the analysis process.
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Minimum flows and levels (MFLs) and Total MaximumDaily Loads (TMDLs)
Minimum flows and levels
The 2007 Florida Statute Subsection373.042(2) mandates that the fiveWater Management Districts setminimum water flows and/or levels(MFLs). The Legislature believed itwas necessary to prevent significantharm to the water resources orecology of an area resulting fromsurface water withdrawals permittedby the Districts.
The MFLs define how often and forhow long high, average, and lowwater levels should occur to preventsignificant harm. The term significantharm however is never clearlydefined making it difficult for theWater Management Districts toactually set reasonable MFLs. In fact,each District takes a different methodon defining significant harm andsome districts like the SouthwestDistrict actually uses up to fivedifferent methods for setting MFLs.Generally, the hydrologic conditionsdefined by established MFLs aresimilar to, but usually lower than theexisting hydrologic conditions. Intheory, MFLs protect bothconsumptive and non-consumptivewater uses.
Minimum flows and levels identify arange of water levels and/or flowsabove which water could be permittedfor consumptive use. Consumptiveuse causes the diminishment of thewater source at the point ofappropriation. Consumptive usesinclude the use of water in suchquantity as is necessary for economicand efficient use for a purpose andmanner that is both reasonable andconsistent with the public interest. Insimple terms, it is for human use fordrinking water, Non-consumptive usecauses no diversion from the watersource or diminishment of the source.Non-consumptive uses includequantities of water necessary fornavigation, recreation, andmaintaining fish and wildlife habitat
levels return to historic levels. On theother hand if water levels continue todrop, previously established MFLswould only indicate that significantharm has occurred or is occurring.
If significant harm has occurred, stateagencies will try to find a way tocorrect for the effects endured undercontinuous minimum lows. Forexample, the Hillsborough River isused as a drinking water source byseveral communities and has beenunder continuous low levels for sometime. The Southwest Florida WaterManagement District (SWFWMD) isattempting to experimentally augmentHillsborough River using water froma flowing sink. They are monitoringground wells and surface waters oflakes to determine potential impacts.If significant lowering of lake levelsoccurs (greater than expected basedon evaporation) then the pumpingfrom the sink would theoretically
as well as other natural resources. It isespecially difficult to set MFLs onmulti-use lakes because asLAKEWATCH always tries toemphasize “a lake can not be allthings to all people.”
Another problem with setting MFLsis that many lakes and rivers do nothave a long-term data base availablefor determining the actual historicalhydrology. Thus, if the MFL processoccurs during a drought period likeFlorida is currently experiencing, orafter significant water withdrawalshave already occurred, the minimumhigh and minimum average levelsmay not recognize any significantharm that has already occurred.Essentially, current impacts duringpresent low water conditions wouldnot be addressed.
Determining the MFLs based on lowconditions could potentially allow forgreater water withdrawals when water
Florida Statutes Subsection 373.042(2) requires the establishment ofMFLs. Establishing MFLs is also a requirement of the StateComprehensive Plan, the water implementation rule, and a 1996Governor’s executive order for priority water bodies. How and when MFLsdeterminations are made are exceedingly important as the programprovides input to the water supply planning process (373.0361, F.S.),permitting criteria for consumptive use permits (Chapter 40C-2, F.A.C.)and environmental resource permitting program (ERP).
Lake Brooklyn in Clay County showing very low water levels.
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cease. The use of water from aflowing sink that is connected directlyto a deeper aquifer will most likelynot impact surface water levelsdirectly. It is essentially agroundwater withdrawal. Results arenot in and LAKEWATCH will try tokeep you updated.
Generally, MFL development is beingdone without reference to existinguses and development, with someexceptions. Districts maintain thereshould be great flexibility inaddressing “significant harm” toinclude regional considerations. Thefollowing are how the differentDistricts look at the concept of“significant harm”:
Northwest Florida WaterManagement District (NWFWMD)No definition, but states it involvesscience-based judgments requiringregional governing board todetermine what functions are to beprotected to ensure a sustainablesystem.
Suwannee River Water ManagementDistrict (SRWMD)No prescriptive definition ofsignificant harm. Staff state theprocess is science-driven rather thanpolicy-driven.
St. Johns River Water ManagementDistrict (SJRWMD)Defines in terms of impact on thestructure and function of ecosystems.Staff states they examine long-termbiological, physical and hydrologicalindicators in an effort to evaluateappropriate levels without referenceto human uses.
Southwest Florida WaterManagement District (SWFWMD)Definition involves protectingexisting as well as future consumptiveuses of water, and at the District’sdiscretion may provide forprotection of non-consumptive uses.
South Florida Water ManagementDistrict (SFWMD)Definition involves science-basedjudgments that should provide forsome acceptable level of harm towater resources from consumptiveuses and flood protection.
Total Maximum Daily Load (TMDLs)
During the last century there havebeen many examples of degradedwater quality in the United States aswell as other parts of the world. Toaddress these problems and protectour Country's vast water resources theFederal government established asubsection in the Clean water Act of1972 to address impaired waters.A Total Maximum Daily Load(TMDL) specifies the maximumamount of a specific pollutant awaterbody can receive and still meetwater quality standards includingpollutant loadings from point andnon-point sources. Legislationestablished means for adoptingTMDLs, allocating pollutant loadingsamong contributing sources andimplementing pollution reductionstrategies. TMDL developmentinvolves determination of the“assimilative capacity” of theimpaired water for the pollutantcausing the impairment. TMDLs aredetermined typically by computermodeling that predicts the fate andtransport of pollutants.
At the Federal level, subsection305(b) of the 1972 Clean Water Act(CWA) requires states, territories andauthorized tribes to develop lists ofpolluted/impaired waters. Thislegislation defines how impairedwaters are to be determined. The USEnvironmental Protection Agencyunder the CWA requires the lists tobe ranked according to priority and todevelop TMDLs of pollutants forthese waters.At the State level, Chapter 99-223 ofthe Laws of Florida sets forth theprocess by which the impaired waterslist will be refined through moredetailed water quality assessments.The 1999 Florida WetlandsRestoration Act (FWRA) clarifiesstatutory authority for TMDLdevelopment and to define theapproval process. This legislationestablished Florida’s 303 (d) list ofimpaired waters that was submitted toUSEPA in 1998 for planningpurposes only. The FWRA requiresFDEP to adopt listing criteria andmethodology by Rule (Chapter 62-303 FAC). Once adopted by Rule,FDEP is required to validateimpairment in listed waters for whichFDEP will calculate the TMDLsprovided for in 403.067 (4) of theFlorida Statutes. This impaired waterslist along with calculated TMDLswill then be submitted to the USEPApursuant 303 (d)(1)c of the CWA. Inaddition, FDEP is required toevaluate whether proposed pollutioncontrol programs are sufficient tomeet water quality standards.
non-point sources and determine theparty responsible for the specificpollution load, identify fundingsources, set forth managementstrategies (stormwater retrofits,wastewater upgrades, bestmanagement practices, etc.), andsecure commitments to implement theactions called for in the plan. EachBMAP will be adopted by an order ofthe Secretary of the FDEP and theimplementation of the BMAP isaccomplished cooperatively withstakeholders and can be viewed as anadaptive management tool. Itssuccess is measured against objectivestandards and, where necessary,changes may be made (throughSecretarial adoption).
The Florida TMDL process has beenformalized by the Florida Departmentof Environmental Protection’s(FDEP) five step approach which canbe summarized as: (1) data collectionand assessment; (2) follow-up datacollection;(3) setting the total allowablepollutant load in the form of aTMDL; (4) development of a BasinManagement Action Plan (BMAP),and (5) implementation of the plan.During the BMAP development stepthe FDEP works with stakeholders toallocate pollutant loads to point and
Lake JoAnna in Lake County during a recentdrought.
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No longer able to sample?If you are unable to collect samples on your lake and would like to resign,please give us a call and let us know. We appreciate all of the hard work thatyou have done and understand that time does not always allow us to geteverything done that we would like. We also ask that you return the samplingequipment to your water collection center or mail to our office as soon aspossible. Be sure to label the equipment kit with your name, lake name andcounty so we can credit you with its return. The equipment used to sampleyour lake is essential for our program and costs about $400 dollars per kit. Itis important that we re-use this equipment to keep our expenses down. If youhave already returned your equipment, thank you very much, but give us acall and let us know so we can update our records.
Water levels low?If you are unable to sample due to low water levels and have not contacted usto let us know please consider giving us a call. We have a toll free number (1-800-525-3928) and it will just take one minute of your time. This will updateour records and help us separate which volunteers can no longer sample dueto low water from those who can no longer sample due to other reasons suchas health, time, or etc.
2007 Fish Report
Volunteer Bulletin Board
Thank You!We take this opportunity to thank you for your hard workand dedication! Using Florida LAKEWATCH techniques, youare documenting your lake's nutrient levels (nitrogen andphosphorus), its algae content, and its water clarity. Thesedata are compiled to create a long term data base that canbe used as an "early warning system" to help spot potentialproblems in their earlier stages. The Florida LAKEWATCHprogram also forms a network for communication, education,and understanding among various groups and individualsinvolved in research, planning, management, and resourceuse. Without your help this information would never havebeen generated. Be proud of yourself!
The 2007 FL LAKEWATCH/Fish andWildlife Conservation Commissionlong-term fish monitoring programreport for 2007 is now available onthe LAKEWATCH website at :
http://lakewatch.ifas.ufl.edu/
The 2007 report as well as a list ofthe lakes sampled are available todownload in pdf format.
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LAKEWATCH NEEDSYOU!
Highlands County
Angelo MaryJaneAnoka McCoyByrd Mills Pond
Chilton MirrorCounterfeit Nellie
Crews OliviaDamon Persimmon
Deer PioneerDiane PythiasDuck RachardFox Saddlebags
Granada SilverHill Trout
Huntley TulaneIsis Verona
Jackson ViolaLelia Wolf
Little Bonnett
Polk County
Annie Blue SouthArbuckle Bonnet
Ariana BonnyAurora BuffumBentley CannonBlue 2 Clark
Seminole County
Ada Island PondAlma JennieAnn Kathryn
Asher LongBanana Marion
Baptismal MillsBel-Air Mirror
Bingham Monroe EastBrantley Mullet
Buck MyrtleCochran Pearl
Cranes Roost PineDeep Plaza Oval
DeForest PrairieDot Quail Pond
East Red BugEast Crystal Silver
Emily TonyEmma Twin East
Florence WekivaForest West Crystal
Fruitwood WildwoodGem Willa
Golden WoodlakeHayes Yvonne
HorseshoeHorseshoe North
Polk County
Clearwater Little Otis
Clinch Little Spirit
Conine Little WintersetCrago Livingston
Deer Lizzie
Eagle LostElbert Lucerne
Eva Mabel
Fannie MarionGarfield Mattie
Gibson Maude
Haines MayHamilton Mirror
Hancock Mountain 2
Hartridge NedHelen Otter
Henry Pansy
Howard PatrickHunter Pollock
Ida Ring
Idylwild RochelleJessie Roy
John Silver
Josephine SmartJuliana Spring
Little Elbert St. Anne
Little Hamilton Symphony
These lakes have been inactive for over one year. If you know ofanyone who might want to sample any of these lakes please
have them call us at 1-800-525-3928 or e-mail us [email protected].
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Florida cannot be beat as the No. 1place to cast a line, pitch a lure orland a lunker. No tall fisher’s talehere — this title has been earned,according to a survey by the U.S.Census Bureau.
Every five years the Census Bureauconducts the “National Survey ofFishing, Hunting and Wildlife-Associated Recreation.” This surveyis the gold standard for comparingoutdoor recreational activitiesbetween the states. Once again itproves that Florida is the number onefishing destination, according to the2006 results.
The facts tell where anglers go for thebest fishing opportunities. Floridaprovided 46.3 million days ofrecreational fishing in 2006 versus41.1 million days in Texas, thesecond highest state. Of fishing daysspent in Florida, 4.8 million dayswere by tourists (nonresidents), whileWisconsin, the second highest statefor tourist days, provided 3.8 milliondays. In terms of nonresident anglers,Florida is also number one with885,000, versus No. 2 North Carolinawith less than half that at 395,000.
But the story does not end there.Overall Florida again ranked first innumber of fishing participants age 16and older with 2.77 million. Runner-up Texas had 2.53 millionparticipants. However, in 2001Florida had 3.10 million anglers, sothere has been a decline ofapproximately 11 percent over fiveyears according to these estimates.
If you look at the decline as apercentage of the population, whichhas been rapidly increasing, thepercent decline is a little moredramatic. In 2001, national rates were16 percent and in Florida 17 percentof the population fished. Those ratesdropped to 13 percent nationally andto 14 percent in the Sunshine State in2006. On the positive side, thenumber of fishing days per angler has
In spite of the national estimates offishing participation for all U.S.anglers (does not include foreignanglers) over 16 years of agedecreasing, actual fishing licensesales for both freshwater andsaltwater have increased in Florida.From 2001-02, with 1,070,577licenses sold to 2006-07 with1,188,092, there was an increase of11 percent in the sale of saltwaterlicenses. Freshwater license salesincreased, from 587,413 sold in 2001-02 to 630,078 in 2006-07, showing anincrease of 7 percent. Although notenough to keep pace with thepopulation increase, it is certainlybetter than competing states.
Florida Still Reigns Supreme asFishing Capital of the World
A young angler enjoys success on a Florida lake.
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increased nationally, with the averageangler fishing 17 days out of the yearin 2006.
Anglers in Florida spent $4.4 billionin 2006, allowing Florida to claimanother No. 1 spot as the place whereanglers spend the most money. TheLone-Star State was second best with$4.3 billion spent on fishing.Recreational fishing dollars helped tosupport 75,068 jobs in Florida, againmaking it No. 1, with Texas trailingbehind with 58,938 jobs. Thiseconomic trend is great news forFlorida partially because state andlocal taxes from the sale of fishing-related goods and services generated$441 million for general funds.
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In calendar year 2006, the NationalSurvey estimated 2.77 millionanglers fished in Florida, and duringfiscal year 2006-07 (July 1 to June30), 1.55 million fishing licenses
were sold. This discrepancy ispartially the result of seniors (age 65and older), resident saltwatershoreline anglers and several othergroups, including those fishing from
licensed saltwater piers or charterboats, being exempt from licensing.No one can dispute the facts andfigures. Florida remains the FishingCapital of the World because of greatresources and responsiblemanagement. With a huge variety offish, fishing waters and fishing stylesto choose from, along with year-round fishing weather, there is littledoubt that Florida will remain theplace to go fishing. You can helpensure a vibrant future with highquality, sustainable and safe fishingopportunities by being an ethicalangler, mentoring a youth or friendand keeping your license current.
Additional information and relevantlinks are also posted the Florida Fishand Wildlife ConservationCommission (FWC) FrequentlyAnswered Questions page atwww.MyFWC.com/fishing/faqs.Click on “What is the value ofFlorida’s Fisheries?”
Figure 1. Number of in-state fishing participants estimated in 2006 for the top five states in the United States.
The latest national survey again shows Florida has more anglers than any other state.
0 1,000,000 2,000,000 3,000,000
Michigan
Minnesota
California
Texas
Florida
In state fishing participants
Jason Bennett displays a largemouth bass caught on the Manatee River inManatee County.
This article was contributed by BobWattendorf of the FWC.
Instant licenses are available onlineat: MyFWC.com/License or bycalling 1-888-FISH-FLORIDA
(347-4356)
VisitMyFWC.com/Fishing/Updates for
more FishBuster columns.
10
If you want to know about Bugg Spring,located in Lake County, Florida off CR470 West of Okahumpka you need to askJoe Branham. He came to live at BuggSprings with his father and mother in1940 from Washington D.C. Joe is now76 and for nearly 50 years he has lived onthe shore of Bugg Spring in his familyhome, which dates back to 1923. As achild he swam, fished and boated in thespring and the mile long spring run thatconnects to the Helena Run to LakeDenham, which was at the end of theHart Line steamboat traffic on thePalatlakaha chain and the original site ofthe town of Okahumpka.
Joe left Bugg Spring to attend college atthe University of Florida and then FloridaState University, where he received 3degrees in zoology, marine biology, andexperimental biology. While heworked on his Ph.D. at FSU, hespent two summers with hisyoung family at the MarineBiological Laboratory in WoodsHole, Massachusetts. In 1965, hereturned to Woods Hole as aLalor fellow and met Dr. AlanBeatty of the Institute of AnimalGenetics in Edinburgh, Scotland.Also in 1965 he received aNational Institute of Health Grantto do post-doctorial work at theUniversity of Edinburgh. Hesailed from the United Stateswith his family, wife Margaret,sons Russell and Charles aboardthe Empress of Canada toScotland.
The family spent two years inEdinburgh while Joe worked onproblems of sperm motility andcapacitation in the lab of NobelPrize winner C.H. Waddington.Next, they left Scotland for theUniversity of Hawaii inHonolulu. While there Joe wasan assistant professor teachingzoology courses indevelopmental biology. Hisresearch interests involved reefecology, primarily the effects ofthe giant crown-of-thorns starfishon coral reef habitats of the
Hawaiian and Marshall Islands. His workwas published in Science and Bioscienceand several other journals. Returning tothe mainland they spent a year at theUniversity of Utah. There he researchedthe stone fly larvae in the mountain riversaround Salt Lake City. His work waspublished in the Canadian Journal ofZoology. Then the family returned toOkahumpka where the family had acitrus business. It was a very happyhomecoming for Joe because he couldintroduce his boys to Bugg Spring, anatural paradise he loved. Once back inLake County Joe was offered a jobteaching at Leesburg High School hisAlma Mater. He was going to be asubstitute for one year while anotherteacher was out on maternity leave, buthe stayed for 22 years. He taught biology,chemistry, general science, andlimnology.
Dr. Joe Branham with his “outstanding volunteer paddle at the 2008Lake County Regional meeting.
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Outstanding LAKEWATCH Volunteer
Joe has been very active as aconservationist in Lake County. Hehas held many committeechairmanships such as an advisorymember of the Lake County WaterAuthority. He worked on the firstLake County Comprehensive Plan, hehelped build Flat Island Nature Trail,served on the Public LandAcquisition Advisory Council ofLake County, and served as a teacherand worker at Trout LakeEnvironmental Center. Joe hascollected over 220 samples forLAKEWATCH since 1990 fromBugg Spring. He has collected nearly20 years of rainfall, water flow, andlake level data to accompany thenutrient data for Bugg Spring. He hasbeen an advocate for minimum flowsand levels that are being established
by the St. Johns River WaterManagement District, and hasshared his scientific informationon Bugg Spring with otherscientists for years.
It is rare to have a professionalbiologist consistently gatheringdata on a unique water body,such as Bugg Springs for thislong period of time. The 170foot spring is one of the deepestof Florida’s beautiful springsand Joe has carefully watchedand enjoyed its beauty andnatural history for many longyears. He is a modelenvironmental citizen that hasworked to preserve a naturalFlorida gem and it is a pleasureto have Joe as a LAKEWATCHvolunteer. Joe’s dedication toBugg Spring goes beyondanything we could have hopedfor from a volunteer when theprogram was created. We donot come across volunteers likeJoe very often and commendhim for his time, energy andcontinued service toLAKEWATCH and LakeCounty.
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There are 18 named coastaldune lakes in south WaltonCounty along 26 miles ofcoastline. These coastal dunelakes are extremely rare. InFlorida, they are found only inthe Florida Panhandle. Aroundthe world, coastal dune lakesalso exist in Madagascar,Australia, New Zealand, thenorthwest Pacific Coast of theUnited States and SouthCarolina. FloridaLAKEWATCH volunteershave been sampling 15 of theselakes over the last 10 years.
Coastal dune lakes are uniqueand generally found within twomiles of the coast and aretypically shallow andirregularly shaped. The wateris composed of both fresh andsalt water obtained fromgroundwater seepage (in bothdirections), heavy rain, and
Walton County Dune Lakes
storm surges. Most of the dunelakes around the world arecalled freshwater lakes withvarying periods of saltwaterintrusion. Lake water isgenerally colored (e.g., tea orblack colored) due to watershedcontributions of dissolvedorganic matter. While theselakes are exposed to normalweather conditions, coastaldune lakes are tremendouslyimpacted by hurricane activity(i.e., storm frequency, strengthand duration).
The coastal dune lakes ofWalton County have anintermittent connection to theGulf of Mexico. This periodicconnection serves as control forflood-level waters by opening aconduit to the Gulf. When alake reaches a critical pre-floodlevel, breaching water forms anoutlet through the dune system
and empties the lake water intothe Gulf. Depending on tidesand weather conditions, saltwater and biota from the Gulffills the void left behind by thelowered water level of the lakeuntil equilibrium is reached andthe opening eventually closes.This exchange forms a brackishwater-body, creating atemporary estuarine ecosystem.Each of the coastal dune lakeshas individual outletcharacteristics, with outletopenings varying in length,frequency and duration. Theseopenings occur based on eachlake’s critical water level,which is driven by droughtsand rainfall. As a result, someof the lakes can be completelyfreshwater, some brackish,and/some salty, with varyingdegrees between stages. The
(Continued on page 12)
An aerial photo of a Walton County dune lake.
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This newsletter is generated by the Florida
LAKEWATCH program, within UF/IFAS. 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 LAKEWATCHDepartment of Fisheries and Aquatic Sciences
7922 NW 71st Street
Gainesville, FL 32653
or call
1-800-LAKEWATCH (800-525-3928)
(352) 392-4817E-mail: [email protected]://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.
Florida LAKEWATCHDepartment of Fisheries and Aquatic Sciences7922 NW 71st StreetGainesville, FL 32653
FloridaLAKEWATCH
mission statement for thisadvisory board is as follows:“To serve, protect andperpetuate the Coastal DuneLakes of Walton Countythrough mitigation of theeffects of development.” TheCDLAB has several objectives,which fall under three majorheadings; 1) Action, 2)Education and 3) PerpetualProtection. One action item isdevelopment of an action plan(essentially a lake managementplan) for each lake. TheChoctawatchee Basin Alliancehas recently requested thatFlorida LAKEWATCH helpwith the development of thismanagement plan so stayposted for updates on theprocess.
changing condition of waterchemistry in the coastal dunelakes makes them biologicallydiverse systems with a dynamicnature. Walton County’stremendous population growth,especially in the vicinity of thecoastal dune lakes has raisedmuch concern over the “health”of these exceptional systems.For this reason, the WaltonCounty Board of CountyCommissioners extendedprovisions in the WaltonCounty Land DevelopmentCode and Walton CountyComprehensive Plan for theprotection of the dune lakes.Additionally, the CountyCommission established theCoastal Dune Lake AdvisoryBoard (CDLAB) in 2002. The
Walton County Dune Lakes (Continued from page 11)
