ESR 12:141-155 (2010)  -  DOI: https://doi.org/10.3354/esr00294

ABSTRACT: Fundulus jenkinsi is a state and federally listed Species of Concern because it is rare and is threatened by human activities, and ecological information is lacking. Fish collected from Louisiana, Mississippi, Alabama, and Florida, USA, during winter, spring, and summer were evaluated for selected habitat-linked reproductive and trophic metrics. Mouth-gape–weight relationships increased with standard length (SL) but did not differ by gender. An exposed genital papilla, an anal sheath, and an elongated posterior anal ray separated mature males from females in 86.7% of the fish examined (year round), and adding vertical bars and dark dorsal pigmentation increased this percentage to 96.7% (seasonal). There was a clear season–size spawning relationship, whereby fish <20 mm SL were immature, and ovary phases and oocyte stages suggested that spawning initiated in spring/early summer. Diet did not vary by size-class but did vary seasonally. Summer diets were most similar to each other compared to other seasons, with prey consisting of arachnids, crab zoea, dipterans, amphipods, hymenopterans, and hemipterans. Aquatic prey size classes shifted with increased fish size and mouth gape, which allowed for larger prey to be consumed. Smaller-bodied terrestrial prey were consistently consumed regardless of fish body size. Overall, reproduction and diet are strongly linked with mid- and high salt marsh access. These data highlight small, interconnected intertidal creeks embedded within salt marshes as access points for reproduction and foraging and suggest that ‘dendritic’ complexes of intertidal creeks should be a focus in conservation planning efforts, and that efforts to restore tidal marsh habitat should attempt to mimic these naturally occurring complexes.

KEY WORDS: Fundulidae · Connectivity · Foraging · Insects · Mid-marsh · High marsh · Salt marsh

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Cite this article as: Lopez JD, Peterson MS, Lang ET, Charbonnet AM (2010) Linking habitat and life history for conservation of the rare saltmarsh topminnow Fundulus jenkinsi: morphometrics, reproduction, and trophic ecology. Endang Species Res 12:141-155. https://doi.org/10.3354/esr00294 Export citation Share:    Facebook - - linkedIn