Quantitative Assessment of Yield, Precision, and Cost-Effectiveness of Three Wetland Invertebrate Sampling Techniques

Abstract

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 costeffective. We compared sampling yield, precision, and costeffectiveness 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.

Beaver-Created Habitat Heterogeneity Influences Aquatic Invertebrate Assemblages in Boreal Canada

“…The strongest trend, regardless of year, was higher species richness, diversity and evenness in vegetated-edge habitats compared to openwater habitats. This finding is similar to other studies that suggest that vegetation within ponds can affect the distribution and diversity of aquatic invertebrate communities (de Szalay and Resh 1996;Meyer et al 2011). In their study, Meyer et al (2011) determined that aquatic invertebrate diversity, abundance and biomass were consistently higher in vegetated-edge habitats than open-water habitats.…”

“…This finding is similar to other studies that suggest that vegetation within ponds can affect the distribution and diversity of aquatic invertebrate communities (de Szalay and Resh 1996;Meyer et al 2011). In their study, Meyer et al (2011) determined that aquatic invertebrate diversity, abundance and biomass were consistently higher in vegetated-edge habitats than open-water habitats. Although we observed a tendency for species richness (S) and density to be higher in wetlands with active beaver populations, there was no significant difference from inactive ones.…”

Insights into biodiversity sampling strategies for freshwater microinvertebrate faunas through bioblitz campaigns and DNA barcoding

“…While many studies have compared the efficacy of various field collection methods for capturing accurate estimates of planktonic invertebrate community structure [21-29], there has been little discussion of the idea of sampling strategy as a whole in terms of study objectives, sampling instrumentation, time commitments, adaptation of field methods in response to environmental heterogeneity, and sorting of samples prior to identification both in the field and in the laboratory. Given that the sample size of microinvertebrate community analyses is always much greater than the resources available to identify each individual organism to the appropriate taxonomic level, this sorting of organisms representing the sample community is of utmost importance.…”

Checklist of insects associated with Salvinia minima Baker in Louisiana, USA

“…Both Mfundisi et al (2008) and Albertoni and Palma-Silva (2006) reported larval Chironomidae as the most abundant macroinvertebrates, but we did not collect these due to our sampling design. Differences in taxa collected across these studies are almost certainly a result of differences in sampling method (Meyer et al 2011). Our sampling effort for associated insects was much more intensive (2600 samples over two years) than other published studies and focused solely on adult insects.…”

“…This suggested that most species that occured in the list were already present in the broader habitat prior to invasion by S. minima and are likely using the mat to exploit new, adjacent microhabitats. Utilizing new collection methods resulted in different taxa collected than expected (Meyer et al 2011) and the use of a long term non-destructive collection method produced crepuscular and nocturnal insects that are not collected by traditional collecting methods. Jäch (1998), representing a range of 6 ecological affiliations with water: A1 (completely aquatic) -A6 (riparian).…”