Meeting Abstract
Introduced species pose a major threat to biodiversity globally. One species of callichthyid catfish, Hoplosternum littorale (Hancock, 1828), was introduced to Florida waters from Neotropical South America and has enjoyed rapid dispersal since first being reported in 1995. Assessing the condition of invasive stocks is an important step in understanding the dynamics and success of introduced populations. In order to quantitatively evaluate the condition of the H. littorale in its nonnative range, this study reports for the first time the length-weight relationship (LWR) and Fulton’s condition factor of the invasive H. littorale in Florida. Sampling was conducted from November 2013 to April 2014 in Tosohatchee Wildlife Management Area in Christmas, Florida. A total of 477 specimens were caught (6.40-13.50 cm TL). The allometric coefficient b of the LWR was greater than the isometric value (b=3.11), suggesting positive allometric growth. The average value for Fulton’s condition factor (K) was 1.396, with no significant differences between size classes. The results differ from data recorded from the fish’s native range, suggesting that this freshwater invasive is flourishing in Florida. Thus, these data could pave the way for additional studies addressing the ultimate causes of the success of H. littorale in Florida (e.g. parasite release). In addition, a new maximum total length of the species is reported.
