SFS Annual Meeting

5/20/2019  |   09:00 - 09:15   |  151 DEF

WHEN AND WHERE DOES THE STREAM PARADIGM FOR THE ROLE OF DETRITIVORES IN LITTER BREAKDOWN APPLY TO SHALLOW STANDING WATERS? Detritus is a major source of nutrients and energy for secondary production in many shallow lentic habitats, and many microcosm studies demonstrate that detritus shredders (e.g., caddisflies, amphipods, isopods) and biofilm grazers (e.g., snails, tadpoles, diptera) are nutritionally dependent on detrital-microbial substrates. Conversely, the impact of these consumers on the overall breakdown of detritus in standing waters is poorly documented compared to streams. We conducted in situ experiments in different types of wetlands using “detritus-tray” leaf packs with fine- (few small animal consumers) and coarse-meshed (all animal consumers) coverings. In two experiments conducted in high-elevation ponds, detritus breakdown was 2-3 times greater with than without consumers (mainly caddisfly shredders). In the other experiments conducted in low-elevation marshes and woodland ponds, animal consumers had trivial effects on detritus breakdown. Our results are consistent with the hypothesis that animal consumers play a small role, relative to microbial decomposers, in many ponds and wetlands. Thus, the “stream paradigm” for detritus breakdown might only apply to the subset of shallow lentic habitats that have high densities of macro-consumers relative to the often highly concentrated and voluminous inputs of detritus.

Scott Wissinger (Primary Presenter/Author), Allegheny College, swissing@allegheny.edu;


Grace O'Malley (Co-Presenter/Co-Author), Allegheny College , omalleyg@allegheny.edu;


Amanda Klemmer (Co-Presenter/Co-Author), University of Maine, klemmer.amanda@maine.edu;


Marieke Perchik Bender (Co-Presenter/Co-Author), Allegheny College, mariekebendernyc@gmail.com;


Jessica Bullis (Co-Presenter/Co-Author), Allegheny College, bullisj@allegheny.edu;


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5/20/2019  |   09:15 - 09:30   |  151 DEF

WETLAND RESTORATION AND FISHERIES OUTPUT: THE NIGERIAN EXPERIENCE Wetland is one of the resources of high value which has been exposed to indiscriminate use. It is an important ecosystem to fish and loss or degradation of wetland will have a direct consequence on sustainable fisheries. This paper reviewed the term “wetland”, its functions and values, importance to fish production in Nigeria and threats to its sustainability. The term “wetland” has been defined by various researchers especially based on their profession and their needs but up till today there is no single definition accepted by all users. In Nigeria, the most commonly adopted is that of RAMSAR convention. Wetland has both marketed and non-marketed functions and values. They provide essential link in the life cycle of 75 percent of the fish and shell fish commercially harvested in the world and are vital to fish health. Despite the importance, there have been exceptional losses of wetlands. Lagos state alone has witnessed more than 96 percent loss. Major threats to wetlands are: agriculture, development, pollution and climate change. Therefore proper management of the wetland ecosystem is important in other to ensure continuous fish production.

Peace Chidinma Wilfred-Ekprikpo (Primary Presenter/Author), Michael Okpara University of Agriculture, Umudike, Abia State, Nigeria, wilfred.ekprikpo@gmail.com;


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5/20/2019  |   09:30 - 09:45   |  151 DEF

EPHEMERAL WETLAND INVERTEBRATES IN A NATURALLY DISAPPEARING HABITAT: EMERGENT PATTERNS OF COMMUNITY DISASSEMBLY Communities inhabiting ephemeral wetlands naturally undergo community disassembly every hydroperiod. Disassembly proceeds through processes including but not limited to emigration, inactivation (diapause, resting eggs, torpor, etc.), or simply killing individuals in the harshening conditions of the disappearing habitat. Emerging from these processes are patterns that can be tracked by following the community structure of ephemeral wetlands through their hydroperiod. We tested the following hypotheses in aquatic invertebrate communities in a group of ephemeral wetlands (Playa Lakes) through their entire hydroperiods in the Pawnee National Grassland in Colorado, USA. As the ephemeral wetlands dried, we expected: 1–Diversity to decrease, 2-Predation to increase, 3-Encounter rates to increase, 4-Immigration of new species to decrease. We found that diversity in the invertebrate community increased in the beginning of the hydroperiod, but decreased towards the end; predation rates increased; encounter rates to be highest in the middle of the hydroperiod; and less immigration to occur as the hydroperiod proceeded. Determining how an ephemeral wetland disassembles is extremely important for understanding the ecology of ephemeral ecosystems. Additionally, monitoring the health of these systems is impossible without knowing when in the hydroperiod sampling is occurring.

Brian O'Neill (Primary Presenter/Author), University of Wisconsin-Whitewater, oneillb@uww.edu;


James H. Thorp (Co-Presenter/Co-Author), University of Kansas/Kansas Biological Survey, thorp@ku.edu;


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5/20/2019  |   09:45 - 10:00   |  151 DEF

ECOTOXICOLOGY EFFECTS OF MICROPLASTIC CONTAMINATION IN FRESHWATER WETLANDS There is increasing evidence for the detrimental effects of microplastic on aquatic consumers. However, far less research has focused on the ecotoxicological community effects of microplastics. I hypothesized that the effects of microplastic pollution on aquatic communities will vary by type of plastic and will be most detrimental among plastics with high volatility (e.g., PVC). To test this hypothesis, I conducted an outdoor mesocosm experiment in 100-L wading pools. I added one of six microplastic types, including the six most commonly used compositions: PVC, polypropylene, PET-G, LDPE, HDPE, and polystyrene. I added microplastics at two concentrations for a total of 12 treatments and a no-plastic control. Mesocosms contained leaf litter, microbes, algae, zooplankton, snails, amphipods, and tadpoles. After two months of community development, I found few effects for most community components. However, I found that tadpole growth was lower at the high contaminant concentration, but only for a subset of the microplastic types. In contrast to expectations, I found that tadpoles gained more biomass with PVC than other plastics, and at the lower microplastic concentration. These results suggest microplastic contamination in freshwaters will have bottom-up effects on aquatic food.

Aaron Stoler (Primary Presenter/Author), Stockton University, aaron.stoler@stockton.edu;


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5/20/2019  |   10:00 - 10:15   |  151 DEF

EFFECTS OF DRAWDOWN HISTORY AND VEGETATION TYPE ON AQUATIC INVERTEBRATE DIVERSITY AND BIOMASS IN A MANAGED WILDLIFE AREA Invertebrates provide a key source of protein and nutrients for waterfowl during breeding and migration. Management of wetland impoundments for waterfowl production is often focused on water level drawdowns to influence vegetation. This study objective was to determine the effects of hydroperiod history and vegetative type on aquatic invertebrate diversity and biomass in managed flowages. In fall of 2016, invertebrates were sampled at Mead Wildlife Area in Milladore, Wisconsin, USA from four flowages with different drawdown years and in shallow areas of submersed, floating, and emergent vegetation. A two-way ANOVA revealed that diversity was influenced by drawdown year (p<0.001) but not by vegetation community (p=0.700). However, post-hoc analysis revealed no correlation between diversity and drawdown year, suggesting site-specific characteristics could be more influential than hydroperiod. Vegetation community (p=0.005) and drawdown year (p<0.001) significantly affected invertebrate biomass. The flowage with the earliest drawdown year had significantly higher biomass, and the samples with submersed and floating vegetation had the highest amount of biomass compared to the other communities. These results suggest that both hydroperiod and vegetation can influence invertebrate biomass, and vegetation may be a stronger driver in this waterfowl prey source.

Kaira Kamke (Primary Presenter/Author), RMB Environmental Laboratories, Inc., kaira.kamke@rmbel.info;


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