Distribution and Foraging Ecology of Hardhead (Ariopsis Felis) and Gafftopsail (Bagre Marinus) Catfishes in The Florida Coastal Everglades Honors Thesis

(2018). Distribution and Foraging Ecology of Hardhead (Ariopsis Felis) and Gafftopsail (Bagre Marinus) Catfishes in The Florida Coastal Everglades .

authors

  • Sisco, Sarah E.

honors thesis advisor

abstract

  • Distribution of the sea catfishes Ariopsis felis and Bagre marinus were investigated using long-term data collected from May 2005–December 2017 in Tarpon Bay, a mangrove estuary that is part of the Everglades National Park. A total of 332 catfish were caught during 452 longlines deployed from May 2005 to December 2017 in Tarpon Bay. Of those, 44 were identified as A. felis, 184 as B. marinus, while the remaining 104 were unidentified. Using a multiple regression approach and multi-model inference, I found that salinity, temperature, and year all showed a positive relationship with the catch rate of both species of catfish. Using a combination of stomach content and stable isotope analysis, I compared δ13C and δ15N with known stomach contents to assess trophic position. Stomach contents of B. marinus (n = 8) were consistent with previous studies that indicate a dominance of crustaceans and teleosts, which was supported by δ15N levels in both fin and muscle tissues. Further, stable isotope analysis indicated that A. felis and B. marinus are feeding within the same trophic level. The movements of these large-bodied fish, particularly in relation to their breeding season, should be further investigated, as they likely represent a temporal prey pulse for larger predators in this sub-tropical estuary.

publication date

  • April 16, 2018

keywords

  • Ariidae
  • Ariopsis felis
  • Bagre marinus
  • Everglades
  • ecology