Tunas off northwest Africa: The epipelagic diet of The Bigeye and Skipjack tunas
نویسندگان
چکیده
Tunas are among the most exploited top predators worldwide, with negative impacts on some of their stocks. Changes in population abundance can impact marine food-webs and have potential to alter entire ecosystems. To better understand exploitation tuna stocks critical habitats, basic knowledge diet these species each region is required. Here, we describe two fished archipelago Madeira, Bigeye Thunnus obesus Skipjack Katsuwonus pelamis, based stomach contents analysis. gain further insights into diet, also assess possible bias caused by occurrence live bait stomachs, compared mercury values those other similar diets that not directly targeted fisheries, tunas from ocean basins. fed mostly Atlantic chub mackerel Scomber colias Trachurus sp., which together contributed 85% total prey weight. Only 7.5% weight was constituted mesopelagic prey, including myctophids cephalopods. had an epipelagic (NF = 97%), representing half weight, despite Longspine snipefish Macroramphosus scolopax Sand smelt Atherina sp. accounting for 62.9% number prey. There were interannual variations likely linked pelagic community shifts. Bait did results analysis observed be part natural both species. Baseline data provided this study should allow more informed decisions efficient ecosystem-based fisheries management.
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ژورنال
عنوان ژورنال: Fisheries Research
سال: 2021
ISSN: ['0165-7836', '1872-6763']
DOI: https://doi.org/10.1016/j.fishres.2021.105914