Diet of an endangered Neotropical catfish (<i>Kalyptodoras bahiensis</i>) from the Paraguaçu River, Bahia, Brazil

Santos, Alexandre Clistenes Alcântara; Souza, Fabiane Barreto; Santos, Edjane Pereira dos

doi:10.1080/01650521.2020.1728031

Cited by 2 publications

(1 citation statement)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This feeding index also prevents potential bias arising from huge numeric variations amongst items/categories, as prey abundance is not necessarily correlated with greater biomass (i.e. several small individuals may account for less biomass than one large individual), thus being largely applied in the literature (Souza et al, 2019;Santos et al, 2020;Reis et al, 2020).…”

Section: Diet and Trophic Strategymentioning

confidence: 99%

The influence of size on the trophic interactions between juveniles of two syntopic Trachinotus species

Souza

Santos

2020

J. Mar. Biol. Ass.

View full text Add to dashboard Cite

Abstract Syntopic species with similar anatomic configuration may face strong competition for trophic resources, thus relying on developed mechanisms to ensure coexistence. The present study investigated the influence of body size on trophic interactions between juveniles of two closely related fish species at three sandy beaches in south-eastern Brazil. A total of 150 fish were sampled, where 103 were identified as Trachinotus carolinus (mean ± SE: weight = 9 g ± 1.13) and 47 as Trachinotus goodei (weight = 46.7 g ± 3.34). A significant size-difference between juvenile Trachinotus was detected by a null-model analysis (P = 0.04), with T. carolinus (TL = 79.6 mm ± 2.4) presenting a smaller body size than T. goodei (TL = 147.7 mm ± 4.2). The main prey items consumed by T. carolinus were Perna perna (IAi = 0.76) and Emerita brasiliensis (IAi = 0.18), whereas the latter was the major T. goodei dietary prey (IAi = 0.71). Both prey were correlated with larger-sized juveniles of each pompano species, whereas smaller fish shared non-preferred trophic items. Such opportunistic behaviour of smaller juveniles may account for the dietary overlap detected between the Trachinotus species (P = 0.09). Size-related dietary partitioning was observed for the largest T. goodei juveniles, which displayed only a slight overlap with T. carolinus, and between juveniles belonging to the small and medium size groups of each pompano species. Therefore, food partitioning related to pompano body size seems to be especially important for the smallest juveniles, as they present the highest vacuity (particularly T. carolinus) in the sampled beaches, suggesting that these individuals are under intra- and interspecific competitive pressure, which may affect local coexistence.