BECAS
VAZQUEZ diego martin
artículos
Título:
Exploring nursery sites for oviparous chondrichthyans in the Southwest Atlantic (36°S?41°S)
Autor/es:
VAZQUEZ, DIEGO MARTÍN; MABRAGAÑA, EZEQUIEL; GABBANELLI, VALERIA; DÍAZ DE ASTARLOA, JUAN MARTÍN
Revista:
MARINE BIOLOGY RESEARCH
Editorial:
TAYLOR & FRANCIS AS
Referencias:
Año: 2016 vol. 12 p. 715 - 725
ISSN:
1745-1000
Resumen:
The aim of this paper was to explore egg-laying areas of oviparous chondrichthyans occurring in the northern part of the Southwest Atlantic Ocean (36°S?41°S) between 50 and 200 metres depth and the Mar del Plata Canyon (from 200 to 3447 m). A total of 515 capsules were collected corresponding to 10 species. Four species accounted for 87.6% of the total catch: Psammobatis normani, Bathyraja macloviana, Amblyraja doellojuradoi and Bathyraja brachyurops. The remaining corresponded to Schroederichthys bivius, Psammobatis rudis, Zearaja chilensis, Bathyraja albomaculata, Psammobatis lentiginosa and Bathyraja sp. Most hauls were monospecific and relatively few hauls contained four or five species (southern part of the area, in sites located at 75 and 94?105 m depth). No egg capsules were recorded between 1712 m and 3447 m. Highest densities (>3000 capsules/km2) were mainly found between 39°46.2′ and 40°29.9′S from 85 to 105 m and they were also recorded near the Mar del Plata Canyon at 37°597′S and at 852 m. The highest value recorded was 12,326 capsules/km2 (located at 40°18.9′S and 85.4 m). The highest densities for each of the most abundant species are discussed. The finding of high densities of egg cases near the Argentine shelfbreak front indicates that many skate species use this area as nursery sites. Egg-laying areas explored here are the first reported sites of this kind in the Southwest Atlantic Ocean. Recognizing and protecting egg-laying habitats may be an important step to a long-term conservation of oviparous chondrichthyan populations.