In addition, the species is less abundant at the one site with 10

In addition, the species is less abundant at the one site with 100 % detectability. It is difficult to compare numbers of specimens collected with previous studies due to variable effort. However, in the 1970s, numbers as high as 83 were reported from one breeding

site collection in the Cypress Creek system. Boschung (1976) estimated 800–1200 Slackwater Darter were selleck chemicals llc present in one segment of Cemetery Branch in the Cypress Creek system, where they are now presumed extirpated. Recent surveys produce numbers of specimens comparable to this at only one site, in the Cypress Creek system, and evidence indicates a decline over time at this location. Since breeding sites are targeted for sampling, it is difficult to compare detectability of non-breeding and breeding sites over time. The species was detected at four of 25

non-breeding sites during this study, however. Non-breeding sites should be included in future monitoring efforts for these species, as the potential environmental stressors in these habitats are poorly known. Although two new breeding sites were discovered during SYN-117 research buy this study, one of them is in an industrial cotton field, and it is doubtful that the seepage habitat will persist due to plowing. There are potential seepage areas in the headwaters of both the Brier Fork and Swan Creek systems, which should be explored and surveyed for Slackwater Darter during the breeding season. The decline in distribution and abundance make detection of this species difficult to monitor. At many sites, numerous samples were necessary for the detection PtdIns(3,4)P2 of Slackwater Darter, suggesting very low numbers of individuals are present relative to historical samples. Future monitoring must include multiple samples at each site to insure detection. Several environmental problems may be contributing to the decline of this species, including various types of passage barriers, habitat degradation and

the destruction of seepage areas via the construction of farm ponds. Boschung (1976) emphasized the importance of connectivity of breeding and non-breeding habitats, and gave a range of bank heights at existing breeding sites as 30–45 cm. Although it is impossible to go back and gather comparative data, data on current bank height ratios, low at extant and Tanespimycin molecular weight higher at apparently extirpated breeding sites and associated stream channels suggest that channel incision may play a role in the decline of this species at some sites. Additionally, culverts at road crossings are known passage barriers to small fishes (Boubee et al. 1999; Kemp and O’Hanlley 2010). Future conservation efforts for this species should include an evaluation of potential environmental impacts on the migration of this species. Prioritization of breeding sites for protection is also essential for the persistence of Slackwater Darter.

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