First description and survey of the egg masses of Loligo gahi and Loligo sanpaulensis from the Patagonian coastal waters

BARÓN, PEDRO J.

JOURNAL OF SHELLFISH RESEARCH

National Shellfisheries Association

Lugar: Connecticut; Año: 2001 vol. 20 p. 289 - 295

0730-8000

A survey was conducted on the egg masses of Loligo gahi D’Orbigny, 1835, a target of an important squid fishery in the Southwest Atlantic, and Loligo sanpaulensis Brakoniecki, 1984, a species exploited as by catch in artisanal fisheries from Brazil to Argentina. The egg masses are described and several spawning areas are identified. L. gahi egg masses were composed of a variable number of capsules (6 to 345) enclosing 40 to 150 eggs/embryos. L. sanpaulensis egg masses consisted of numerous capsules (6 to 465) containing approximately 240 to 320 eggs/embryos. The size range of the eggs was 2.1-2.3 mm for L. gahi and 1.2-1.3 mm for L. sanpaulensis from Nuevo Gulf, showing good correspondence with size of the mature oocytes carried in the oviducts by the females of each species at the same location. L. gahi egg masses were located in San Matías, San José and Nuevo gulfs, Cape Tres Puntas and Beagle Channel, usually attached to hard substrates including kelp or objects laying on the seafloor, such as stones, shells, ropes or even fishing lines, at depths ranging from 1 to 15m. L. sanpaulensis egg masses were found in Nuevo Gulf on sandy and muddy bottoms at a depth range of 5-15 m. Throughout a survey conducted from March 1996 to February 2000 in Nuevo Gulf, an area within the distribution range of both species, L. gahi egg masses were the ones found more frequently, being present on every month of the year but February, while L. sanpaulensis egg masses were only detected from February to May.