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This preliminarily study aims at increasing our understanding of an assemblage of coastal batoids on the northern coast of Peru by determining species composition, body size structure and its behaviour in marine-coastal zone of Los Órganos, Piura Region, Peru. During 20 field trips, between the years 2016, 2017, and 2019, eighty-six individuals were sampled belonging to eight species: Zapteryx xyster (n= 22), Narcine entemedor (n= 11), Urobatis tumbesensis (n= 7), Urotrygon chilensis (n= 40), Pseudobatos planiceps (n= 1), Urobatis halleri (n= 1), Gymnura crebripunctata (n= 2), Aetobatus laticeps (n= 2). In the study area, a predominance of adult females was observed for Z. xyster, N. entemedor and U. chilensis. These preliminary results suggest that during the morning some batoid species (i.e., Z. xyster, N. entemedor, U. chilensis) use the coastal zone to rest since they are found inactive and partially or totally buried in the sand - N. entemedor could be also hunting through ambush. Future studies should determine if this is a gestation area for some of these batoid species. [ABSTRACT FROM AUTHOR]

This study provides information about the diet across geographic areas and throughout ontogeny and sex of two coastal and commercial batoid species in Peru (Chilean eagle ray Myliobatis chilensis and Pacific guitarfish Pseudobatos planiceps). Data was collected in the central coast (13°30′S to 14°30′S; Pisco district, Lima) and in the northern coast (13°12′S to 13°49′S; San Jose district, Lambayeque) off Peru during the second semester of the years 2015 and 2016 (i.e., winter and spring) in an El Niño event. A total of 357 stomach contents were analyzed in northern and central Peru with different oceanographic and ecological conditions. In the central coast, M. chilensis showed a high trophic position (tertiary consumer) due to its high consumption of Peruvian anchoveta (Engraulis ringens), while P. planiceps had a lower trophic position (secondary consumer) and a less specialized diet of benthic invertebrates (i.e., crustaceans and mollusks) and pelagic fish (e.g., E. ringens). In the northern coast, both species preyed mainly upon benthic invertebrates and to a lesser degree on fish; therefore, their trophic position was lower. Dietary variation was influenced by species, geographic location, and ontogeny. The diet variability between geographic locations shows insights of these batoids' trophic plasticity and opportunistic feeding behavior in response to differences in the local prey availability, an effect that may be amplified during the El Niño–Southern Oscillation (ENSO). The spatial variation in this species diet may indicate that they play different ecological roles in distinct environments. This study contributes to the scarce literature about batoids' ecology in the southeast Pacific Ocean and presents novel information on habitat-specific diet composition. [ABSTRACT FROM AUTHOR]

The Peruvian sea represents one of the most productive ocean ecosystems and possesses one of the largest elasmobranch fisheries in the Pacific Ocean. Ecosystem-based management of these fisheries will require information on the trophic ecology of elasmobranchs. This study aimed to understand the diet, trophic interactions and the role of nine commercial elasmobranch species in northern Peru through the analysis of stomach contents. A total of 865 non-empty stomachs were analysed. Off northern Peru, elasmobranchs function as upper-trophic-level species consuming 78 prey items, predominantly teleosts and cephalopods. Two distinctive trophic assemblages were identified: (a) sharks (smooth hammerhead shark Sphyrna zygaena, thresher shark Alopias spp. and blue shark Prionace glauca) that feed mainly on cephalopods in the pelagic ecosystem; and (b) sharks and batoids (Chilean eagle ray Myliobatis chilensis, humpback smooth-hound Mustelus whitneyi, spotted houndshark Triakis maculata, Pacific guitarfish Pseudobatos planiceps, copper shark Carcharhinus brachyurus and school shark Galeorhinus galeus) that feed mainly on teleosts and invertebrates in the benthonic and pelagic coastal ecosystem. This study reveals for the first time the diet of T. maculata and the importance of elasmobranchs as predators of abundant and commercial species (i.e., jumbo squid Dosidicus gigas and Peruvian anchovy Engraulis ringens). The results of this study can assist in the design of an ecosystem-based management for the northern Peruvian sea and the conservation of these highly exploited, threatened or poorly understood group of predators in one of the most productive marine ecosystems., (© 2020 Fisheries Society of the British Isles.)

Angel sharks are distributed worldwide in tropical to subtropical waters. Across the Eastern Pacific Ocean (EPO), two valid species are reported: The Pacific angelshark Squatina californica and the Chilean angelshark Squatina armata; however, there is still uncertainty about their geographic distribution, mainly along the northern Peru coast where the species have been reported to be sympatric. The aim of this study is to describe the genetic differences between the genus Squatina from the EPO, including samples from northern Peru, and using DNA barcoding and three species delimitation models: Poisson tree processes (PTP) model, Bayesian implementation of the PTP (bPTP) model and the general mixed Yule coalescent (GMYC) model. The three approaches summarized 19 nominal Squatina species in 23 consensus Molecular Taxonomic Units (MOTU). Only 16 of them were in accordance with taxonomic identifications. From the EPO, four Squatina MOTUs were identified, one from North America (S. californica USA/Mexico) and three sampled in northern Peru, S. californica Peru, S. armata and Squatina sp. (a potential new species). This study contributes to the management and conservation policies of angel sharks in Peru, suggesting the presence of an undescribed species inhabiting the northern Peruvian coast. The use of molecular approaches, such as DNA barcoding, has the potential to quickly flag undescribed species in poorly studied regions, including the Southeast Pacific, within groups of ecologically and economically important groups like angel sharks. [ABSTRACT FROM AUTHOR]