Diet of Lontra longicaudis in La Sangría Lagoon, México

Abstract

There are records of Neotropical otters, Lontra longicaudis in Campeche, but ecological information is scarce.  The diet of this species inhabiting La Sangría Lagoon, México, was analyzed to record feeding preferences over a year through the identification of undigested remains.  Data were obtained from feces and feeders.  Once per season (winter rainy season or nortes 2016, dry, and rainy 2017), 11.9 km of the shoreline was traveled.  One hundred twenty-six feces and one feeder were collected in 52 sites.  These samples were analyzed by assessing the percentage of occurrence (PO) and ecological niche width (Levin’s index) through the identification of undigested remains to the finest taxonomic level possible.  Seven major groups of prey were identified: fish, crustaceans, mollusks, mammals, birds, and others.  From a total of 16 prey categories, fishes were the best represented with a higher PO and number of genera, including janitor fish (invasive species), followed by crustaceans and mollusks.  There were no variations in the frequency of prey consumption by season, but there were statistical differences in the diversity of species consumed.  Three native fish species and 4 potential new records of fish were confirmed as prey of Neotropical otters. Levin’s index showed that La Sangría Lagoon has a niche width with a trend toward specialization for the otter (0.2078).  Comparing the diet observed herein with literature reports for other localities confirms the trophic adaptability and highlights the ecological value of the Neotropical otter.