CIIIPIII.A'tlat,'-8COPY RIU-G 9Q-001 C2 Sea6raot OaIjository Winter Flounder in Rhode Island Coastal Ponds Richard Crawford OB ~SZ ~O 0 ~ GRP Additional copiesof this publicationare availablefrom; Rhode Island Sea Grant Publications, University of Rhode Island Bay Campus, Narragansett, RI 02882-1197. Order P1133. Nationa1 Sea Grant Depository Publication IRIU-G-90-00L Loan copies available from the National Sea Grant Depository, Pell Library Building, University of Rhode Island Bay Campus, Narragansett,RI 02882-1197, Rhode Island Sea Grant. March 1990. Editing and layout by Eleanor Ely, Rhode Island Sea Grant, Cover photo: An adult winter flounder lying in the sand. The ~inter flounder's cryptic colorationallowsit to blendinconspicuouslyintoits environment, thus protecting it from predators. Photograph by Ilarold Wes Prat t. SeaGrant is a nationalprogram working to ensurethe wise useand conservationof marine resourcesfor the public benefi , Table of Contents 2 PREFACE 2 ACKNOWLEDGEMENTS 3 INTRODUCTION 6 HABITS OF COASTAL POND WINTER FLOUNDER Preparation for spawning season Spawning and early life history 8 COASTAL POND WINTER FLOUNDER FISHERIES Recreational fishery Cointnercial fishery 11 NEW KNOWLEDGE OF WINTER FLOUNDER BEHAVIOR Winter flounder spawning areas Distribution of winter flounder larvae Movements of adult winter flounder 18 CONFLICTS BETWEEN THE RECREATIONAL AND COMMERCIAL FISHERIES 18 RECENT CHANGES IN THE COMMERCIAL FISHERY 21 SUMMARY AND RECOMMENDATIONS 22 CONCLUSION 23 BIBLIOGRAPHY 24 APPENDI X List of fish species found in Rhode Island coastal ponds PREFACE This work was part of the University of Rhode monitor the use and abuse of the resources for Island URI! Salt Ponds Study. Information from which they have shown such great concern. this studywas usedin the preparationof thc Rhode This paperreports the resultsof the finfish Island Coastal Zone Management Plan and the segmentof the Salt PondsStudy. It was written for SpecialArea ManagementPlan for RhodeIsland's the users of Rhode Island's coastal ponds, in the coastal pond regions. The Salt Ponds Study was a continued belief that without informed stewardship very successful multidisciplinary investigation that of resourcesby local users those resources are in has been adopted as a model for similar studies dangerof beinglost. That suchstewardship can elsewhere in the United States and abroad. One occur has been demonstrated by the involvement of reason for its success was the involvement of the Rhode Island's coastal pond watchers. This paper people who use the resources.This involvement was written for them and for those who share their continues today in the Rhode Island Sea Grant concern for the sustained well-being of these re- Pond Watchers Project, in which local residents s aurces. ACKNOWLEDGEMENTS This paper reflects the labors of many people ponds,they kept recordsof fishing activity and who worked on the fisheriescomponent of the URI other noteworthy events to keep me better in touch Salt Ponds Study. It also includes insights gained with the happenings on the ponds. I also want to by other research teams in the study, as well as thank commercial fishermen Richard Johnstone and ideas gleaned from innumerable conversations with William Sieczkiewicz for providing me with their fishermen while on the ponds. I am gratefully observations and catch records and for assisting indebted to all of the contributors, and same with the Ninigret Pond stock assessment. warrant special mention. Finally, my heartfelt appreciation is extended to Many students at the URI Graduate School of Stephen Olsen, Director of the Coastal Resources Oceanography worked on this project. Without Center. As coordinator of the Salt Ponds Study, he their participationthis work would neverhave been provided the glue that so successfully held together accomplished. Constance Carcy! Grove and Mary the various components of that eclectic investiga- Worobcc became accomplished draggerwomcn and tion. He also gave invaluable advice during the prepared graduate theses from stock assessmcntsof preparationof this paperand it has benefited flounder in Point Judith and Ninigrct ponds, re- immensely from his comments. spectively. Kim Billington, Leslie Bulian, Mary This work was administered by the Rhode Island Fabrizio, Bob Sand, Skip Cynar, Lynne Hanson, Sea Grant office and was financed in part by and others provided excellent support in various ca- NOAA Office of Sea Grant, U.S. Department of pacities during the project. Numerous students, URI Commerce, under Grant INA79AA-D-00096, and staff members, Department of Environmental Man- in part by the National Oceanic and Atmospheric agcrncnt personnel, and colleagues at the Coastal Administration, under the provisions of the Coastal ResourcesCenter also assisted in numerous ways Zone Management Act of 1972 Public Law 92- during the five years of research.A special thank 583!. This publicationwas producedunder NOAA you goes to the local residents who volunteered as Office of SeaGrant, U.S, Dcpartinentof Com- "pond watchers." From vantage points around thc merce, under Grant ONA89AA-D-SG-082. INTRODUCTION During the 1960sand early 1970s,Point Judith botherto go out any more.There was no doubt in Pond andNinigret Pond Figure 1! ratedvery high their minds that there were not as many fish as amongrecreational fishermen as exceptionally there used to be. good fishing areas.Some claimed that on a good Therewere manyopinions about the causefor day you could catchas many fish there as you the perceiveddecrease in winter flounderlandings. could at the well-known regional "hot spot" off At the time of our surveysbetween 1978 and 1983, Quincy, Massachusetts. the most frequentlyexpressed belief amongrecre- By the mid 1970s,however, there werc signs ational fisherrncn was that the problem was the that not all was weLl with this popular fishery. Rec- impact of commercialharvests within the ponds. reationalfishermen recalled years when they had Two men operatedsmall otter trawls there,as they caughtmore fish and complainedthat the fish they had done during the previous decade. To recrea- now caught were smaller. Previously productive tional fishermen, they were a visible source of placessuch as GreenHill Pondchannel Figurc 3! compeiitionand potentialimpact on the winter did not seem to yield as many fish as they once did. flounder. Less conspicuous was the commercial Old-timers who used to spear a bushel-basketful of fykc-net fishery. A fyke net is a funnel-shapedtrap floundcr off the channel's sand flats didn't even made of fish net. Fish are typically guided to the o3 41 30 4 I' 25 41 ' 20 71 50 71' 40 71 30 Figure 1. I hefour RhodeIsland coastalponds studied during the UR/ Salt Pond Study, mouth ol' the net by wings of netting stretching out the perceived problem with the resource was real. froin either side, Fish entering the fyke nct are There is a long history of concernfor the winier trapped until a fisherman removes them. Several flounder in Rhode Island waters. Prior to the turn of pcoplc sct theseportable fish traps in Point Judith, the century,biologists recognizedour estuariesand GreenHill and Potterponds. These nels were coastal ponds as places where winter flounder placed in areas less frequcntcd by recreational spawn and their young develop. In fact, during thc fishcnncn, so the fykc-nctlcrs received less vocal first severaldecades of this century the state of opposition than the Ninigret Pond draggermen. Rhode Island operateda winter flounderhatchery in Some recreational fishermen also believed that Wickford. Its purpose was to augment the natural increased fishing pressure by thc commercial fleet supply of young flounderso that populations sup- operating outside the ponds in Rhode Island and porting the important inshore commercial flounder Block Island sounds may have had an impacton the fishery would be maintained or perhaps increased. winter flounder resource. Others attributed the Iluc- It was never conclusively demonstrated that hatch- tuations in flounder abundanceto a natural phenom- ery production influenced commercial fishery enon regulated by changes in temperature and other landings,and the hatchery closed in thc late 1930s. cnvironmcntal variables Jeffries and Johnson That a single, small hatchery had little impact on 1974!. There was plenty of discussion but liitlc the numbers of young flounde developingin our «grccment. No onc could even say for sure whether coastalwaters is really no surprise, We now know that, in addition to the vast numbers of young flounder produced in Narragansett Bay and its estuaries,millions arc produced in our coastal ponds each year. Nature has provided hcr own hatcheries. The quantitics produced by the hatchery in Wickford pale in comparison to nature's efforts. F<QUr82. Point Judith and Potterponds study area features. Fig Ul'e 3. Nittigret and Green Hill ponds study area features. Table 1. Characteristicsof thefour RhodeIsland studyponds and their watersheds. Point Judith Potter Nlnlgret Green Hill Ponds: Hectares 638 137 713 180 Average depth meters! 2 1.2 1.2 0.8 Average salinity o/oo! 29 28 28 24 Breachway dimensions meters! width 50 7 34 depth 8 1.5 2 Watersheds 980!: Hectares 2245 1068 3058 1700 Land use '%%d! developed 34,6 21.5 16 28 agricultural 3.9 10.4 3.2 5 woodland/open space 54.9 63 66.1 65 conservation 1.7 15 2 houses 2028 755 1215 1223 projected houses at full development 6828 1902 4816 3850 Freshwater input 0' rn'/yr! 25.3 5 15 6.8 HABITS OF COASTAL POND WINTER FLOUNDER The winter flounder, Pseudopleuronecresameri- diameter. As the eggs are developing in the fe- canus also known locally as blackback or simply males, the bellies of males also become distended "flounder" !, is a cold-water species with a special from the swelling of maturinginilt sacs.By mid- ability to withstand near-freezing temperatures. February,the gonadsof both sexesare fully devel- During winter months,these fish producewithin oped,but the energeticcost of this developmentto their tissues an organic antifreeze compound other tissues is apparent in the skinny and flaccid similar to glycoproteinsfound in certainspecies of quality of the musculature.A fillet from a fish in Antarctic fish Duman and deVries 1974!.