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This poster was presented at the 2024 UCSB EEMB Research symposium.Aquatic macroinvertebrates are critical indicators of ecological health because of their role as primary consumers, supporting many species within their respective food chains. Birds, as key components of wetland ecosystems, heavily rely on these aquatic macroinvertebrates as a food source. Understanding the dynamics between aquatic macroinvertebrates and environmental factors is crucial for effective ecosystem management efforts. This study compares surface sampling data and benthic dipnetting sampling data across multiple sites within North Campus Open Space (NCOS) from the summer of 2023 to the spring of 2024. Our research aims to determine the species abundance and diversity of key aquatic invertebrates and zooplankton using the Shannon–Wiener diversity index. By utilizing two distinct sampling methods, we investigate the effectiveness of the sampling techniques through potential variations in species abundance. Moreover, we correlate this data with water quality parameters such as pH, salinity, and dissolved oxygen to assess their influence on the distribution and abundance of aquatic macroinvertebrates. Overall, this research contributes to a deeper understanding of the intricate relationships between environmental variables and aquatic macroinvertebrate abundance across two different sampling mediums.

Dipnet (DN) sampling is routinely employed for macroinvertebrate bioassessments in wetlands, but it has been demonstrated that some taxa are more effectively collected with activity traps (AT). The Minnesota Pollution Control Agency (MPCA) used both DN and AT methods to evaluate the biological condition of depressional wetlands in the Mixed Wood Plains (MWP) and Temperate Prairies (TP) ecoregions. Two indices of biotic integrity (IBIs) were developed for each ecoregion using: 1) DN data alone and 2) composite samples consisting of both DN and AT data. ATs collected more active taxa such as diving beetles and swimming Hemiptera. DNs collected more taxa and collected more skating taxa and those associated with sediment or vegetation. A comparison of the effectiveness of the IBIs to evaluate biological condition indicated that the composite data had a slightly better relationship with anthropogenic disturbance and was marginally more precise. A comparison of sampling and processing costs revealed that sampling using composite samples was 130 % greater and processing was 50 % greater compared to DN-only samples. Based on the cost and limited benefit of adding AT samples, a DN-only sampling protocol is recommended to assess biological condition in depressional wetlands. [ABSTRACT FROM AUTHOR]

Macroinvertebrates are increasingly used as indicators of wetland integrity and productivity. However, accurate interpretation of biological information depends on effective sampling methods, which are also preferably cost-effective. We compared sampling yield, precision, and cost-effectiveness of two traditional wetland sampling methods (dipnet, stove pipe corer) to a dipnet combined with a dropframe in wetlands in the Platte River Valley, USA. The dropframe method was designed to be more quantitative than standard dipnet techniques and to maximize capture of mobile taxa. We compared measures of macroinvertebrate community structure (e.g., abundance, richness, diversity) and function (functional structure, habitat associations), as well as processing time for each sampling technique in vegetated and non-vegetated habitats. Vegetated habitats harbored higher richness, diversity, abundance, and biomass of most invertebrates. The dipnet consistently yielded the lowest values in vegetated and non-vegetated habitats, suggesting that sampling with a dipnet alone can greatly underestimate macroinvertebrate populations and diversity. The corer and the dropframe yielded similar results, but the dropframe produced significantly higher richness values. While the dropframe appeared to be a good choice for sampling in these wetlands, sample processing times for this method were more than two times longer than the other methods. Results provide a basis for informed decisions regarding quantitative sampling of wetland macroinvertebrates. [ABSTRACT FROM AUTHOR]

To design effective and efficient research and monitoring programs researchers must have a thorough understanding of the capabilities and limitations of their sampling methods. Few direct comparative studies exist for aquatic sampling methods for amphibians. The objective of this study was to simultaneously employ seven aquatic sampling methods in 10 wetlands to compare amphibian species richness and number of individuals detected with each method. Four sampling methods allowed counts of individuals (metal dipnet, D-frame dipnet, box trap, crayfish trap), whereas the other three methods allowed detection of species (visual encounter, aural, and froglogger). Amphibian species richness was greatest with froglogger, box trap, and aural samples. For anuran species, the sampling methods by which each life stage was detected was related to relative length of larval and breeding periods and tadpole size. Detection probability of amphibians varied across sampling methods. Box trap sampling resulted in the most precise amphibian count, but the precision of all four count-based methods was low (coefficient of variation > 145 for all methods). The efficacy of the four count sampling methods at sampling fish and aquatic invertebrates was also analyzed because these predatory taxa are known to be important predictors of amphibian habitat distribution. Species richness and counts were similar for fish with the four methods, whereas invertebrate species richness and counts were greatest in box traps. An effective wetland amphibian monitoring program in the southeastern United States should include multiple sampling methods to obtain the most accurate assessment of species community composition at each site. The combined use of frogloggers, crayfish traps, and dipnets may be the most efficient and effective amphibian monitoring protocol. [ABSTRACT FROM AUTHOR]