Browsing SUNY Brockport by Subject "Habitat Assessment"
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A Quantitative Survey of the Freshwater Mussel (Unionidae) Fauna in Honeoye Creek, New YorkContemporary baseline data such as species presence, distribution, abundance, size-class structure, species-habitat relationships, and host species distributions are needed for monitoring the status and health of freshwater mussel communities in Honeoye Creek and other watersheds in New York State in the future. Quantitative surveys were performed at 20 sampling sites to assess the status of freshwater mussels in Honeoye Creek. Fifteen species were observed throughout the creek, with the highest diversity of nine species at two sites. Mussel abundance ranged from 0 to 3.15 mussels/m2. Recent recruitment was observed in five species, including Fusonaia flava, Lampsilis cardium, Lampsilis siliquoidea, Strophitus undulatus, and Villosa iris. Physical and chemical habitat parameters were assessed at each of the 20 sites sampled for mussels. Instream cover, embeddedness, velocity/depth regime, and frequency of riffles were positively correlated to mussel density. Discriminant analysis produced a single function positively correlated with instream cover and velocity/ depth regime. The analysis was able to correctly classify 95% of sites based on presence/ absence of freshwater mussels. A survey of host fishes provided additional data regarding the reproductive potential of freshwater mussels. Twenty seven fish species, including 19 known mussel hosts, were caught during the surveys. Host fishes were not collected for 2 Leptodea fragilis, Potamilus alatus, and Truncilla truncata, a finding consistent with the low abundances of these three species in Honeoye Creek. While these data provide a base-line for freshwater mussel diversity, abundance and distribution, additional research is needed to monitor the status and health of freshwater mussel communities in Honeoye Creek. Future research will help identify trends in population health and target sites where management and conservation measures are needed.
Evaluation of the Basis and Effectiveness of Habitat Assessments in Wetland Functional Assessment MethodsI studied the basis and effectiveness of wetland assessment methods in providing habitat assessments. While it is well understood that wetlands and riparian areas provide important ecological functions and habitat for a wide variety of wildlife species, much is still to be learned about providing meaningful, accurate and repeatable methods for assessing them. I examined and evaluated four assessment methods to determine their accuracy and usefulness in assessing a site's provision of habitat. One hypothesis I tested is that if the assessment methods studied provide an accurate assessment of wetland functions, then the resulting site scores for the methods should be correlated. The second hypothesis is that there is a correlation between the site scores and an independent measure of function, specifically the number of riparian-associated bird and butterfly species observed at each site. Biological and physical data collected from 47 riparian sites in California's Central Valley were used to calculate site scores using Habitat Assessment Technique (HAT), Rocky Mountain Riparian Hydrogeomorphic (HGM), Southern California Riparian Model, and Reference Wetland assessment methods. The rankings of these site scores were also calculated for each method. Correlation coefficients (r) were calculated between the site scores of the four methods, as well as between the site scores and the numbers of riparian-associated bird and butterfly species for each plot. The site scores were mostly uncorrelated. Only one statistically significant correlation was demonstrated between the site scores for the Southern California Riparian Model and Reference Wetland methods (df = 46, r = 0.46, p = 0.00103, with Bonferroni correction). With Bonferroni corrections (p < 0.00625), the site scores were also uncorrelated with the numbers of riparian-associated bird and butterfly species. Without Bonferroni corrections, only two statistically significant correlations were demonstrated: between the number of riparian-associated bird species and the HAT score (df = 46, r = 0.37, p = 0.0095) and the number of riparian-associated butterfly species and the Reference Wetland score (df = 46, r = 0.38, p = 0.0092). I rejected both original hypotheses, which demonstrated that the assessment tools currently available do not consistently produce relatively precise, or reproducible results. Possible reasons for these problems include attempting to assess a function that is too broadly defined, inappropriately or subjectively selected variables, subjectively assigning values to variables, or inappropriately selecting reference sites. The existing attempts at assessing wetland or riparian function are important steps in the right direction toward assessment of wetland and riparian sites and achievement of "no net loss," but functional assessment must be considered a work in progress.