Feeding Habits and Trophic Level of the Panama GruntPomadasys panamensis, an Important Bycatch Species from the Shrimp Trawl Fishery in the Gulf of California

Abstract

The Panama grunt is an abundant and commercially important species in the southeastern Gulf of California, but the research undertaken on this species is scarce despite its ecological and economic importance. We studied the feeding habits of Panama grunt through stomach content analyses as a first step towards understanding the biology of this species in the study area. Our results indicate that the Panama grunt is a benthic predator throughout its life cycle and feeds mainly on infaunal crustaceans. Diet differences among grunt were not found according to size, diet, or season. Shannon diversity index results indicate that Panama grunt has a limited trophic niche breadth with a diet dominated by a limited number of taxa as crustaceans. The estimated trophic level of this species is 3.59. Overall, the Panama grunt is a carnivorous fish occupying the intermediate levels of the trophic pyramid.

Trophic niche of the Pacific Sierra (Scomberomorus sierra) in the southeastern Gulf of California: Assessing its importance as a predator and prey (Mesopredator) in the food web

“…invertebrates, fish, cetaceans, and turtles), some of them with significantly high endemism (Brusca, 2010) and others with incalculable economic and ecological value (Torres‐Rojas, Hernández‐Herrera, Ortega‐García, & Domeier, 2013; Torres‐Rojas, Hernández‐Herrera, Ortega‐García, & Soto‐Jiménez, 2014). For example, a well‐developed tuna, shark, shrimp and sardine fisheries, as well as hundreds of skiffs dedicated to small scale fisheries; all exploit the resources of this region (Ramírez‐Rodríguez, Amezcua, & Aguiar‐Moreno, 2014; Rodriguez‐Preciado et al, 2014; Torres‐Rojas, Páez‐Osuna, et al., 2014; Alatorre‐Ramirez et al, 2017). However, there is still limited knowledge about the trophic interactions of the species subject to exploitation and of the food web structure at southeastern GC.…”

Resource partitioning across a trophic gradient between a freshwater fish and an intraguild exotic

“…While diet studies have previously been conducted for white perch and yellow perch in Lake Erie (Parrish & Margraf, 1990, 1994; Schaeffer & Margraf, 1986a), contemporary comparisons, that is, since the proliferation of dreissenid mussels (Burlakova et al., 2014), of their feeding ecology and trophic position were not available. We used a variety of indices to better understand the trophic level and relative position of white perch and yellow perch along the generalist–specialist continuum (Christensen & Walters, 2004; Pauly & Watson, 2005; Rodríguez‐Preciado et al., 2014). Trophic level ( TL ) was calculated as follows:where the product of the proportion (i.e., % F ) of the j th prey in i th consumer (DC ij ) and the trophic level of the jt h prey was summed across all G prey taxa (Rodríguez‐Preciado et al., 2014).…”

Feeding Ecology and Distribution of an Invasive Apex Predator: Flathead Catfish in Subestuaries of the Chesapeake Bay, Virginia

“…We also calculated a dimensionless omnivory index for Flathead Catfish, which provides valuable information on diet specialization (Christensen and Walters ; Rodríguez‐Preciado et al. ). Omnivory indices (OI) were calculated using the formula…”

“…When OI = 0, the consumer is specialized and only feeds on one trophic level; conversely, an OI value > 0.5 would indicate nonspecialization and feeding on many trophic levels (Christensen and Walters ; Rodríguez‐Preciado et al. ). The square root of a consumer's OI is the SE of its trophic level (Rodríguez‐Preciado et al.…”