Distribution, Abundance, and Habitat Characteristics of Fundulus jenkinsi (Evermann) (Saltmarsh Topminnow) in Coastal Mississippi Watersheds, with Comments on Range-Wide Occurrences Based on Non-Vouchered and Museum Records

Fundulus jenkinsi (Saltmarsh Topminnow) is listed as "at risk" by the USFWS and as a Tier 2 conservation priority in Mississippi, in part, because of marsh-habitat loss due to storms, urbanization, and its specialized habitat requirements and limited geographic distribution. To provide additional quantitative data for conservation planning, our objectives were to (1) determine the distribution and abundance of Saltmarsh Topminnow within coastal Mississippi, (2) characterize its habitat requirements, and (3) organize and present all Saltmarsh Topminnow data records (non-vouchered and museum records and those from this study) for use in the development of management/conservation plans. We collected 497 fish and associated habitat data from 27 February to 1 August 2009. PCA produced 3 meaningful components: (1) a landscape-position axis (32.40% of the total variance), (2) a seasonal/spatial axis of species occurrence (18.99%), and (3) a geomorphic bank-slope axis (18.78%). Ninety-six percent of all fish (representing 78.8% of collection effort) were captured in water with salinity <13 psu. We compiled 831 geo-referenced occurrences with collection dates ranging from 1891 to 2015. To better quantify and conserve the closely-linked habitat requirements of this species within a reduced salinity range, additional sampling should be focused in undersampled areas between Lake Borgne, LA, to west of Galveston Bay, TX.