Turkish Journal of Fisheries and Aquatic Sciences
2018, Vol 18, Num, 2 (Pages: 247-257)
Comparative Pattern of Octopus vulgaris Life Cycle with Environmental Parameters in the Northern Alboran Sea (Western Mediterranean Sea)
2 Facultad de Ciencias del Mar. Universidad de Vigo. Campus universitario Lagoas-Marcosende, 36200, Vigo, Spain
3 Universidad de Málaga. Departamento de Biología Animal, Facultad de Ciencias, Campus Universitario de Teatinos s/n. 29010 (Málaga), Spain DOI : 10.4194/1303-2712-v18_2_04 Viewed : 4634 - Downloaded : 3484 Octopus vulgaris is a short living species with environmental adaptive plasticity and high fecundity. Its abundance can experience large fluctuations highly dependent on the recruitment success. Both, these abundance fluctuations and the reproductive season seem to be influenced by the variability of environmental conditions which can determine the beginning and the length of the spawning period, the existence of one or several spawning peaks and the length of both the embryonic and planktonic phases. Beside this inter annual variability, the availability of long time series of octopus landings and biological data can allow us to define a mean or average length for the different phases of the octopus life cycle. Time series for landings, biological and environmental data in the Alboran Sea are analyzed in the present work. Sexual maturity data are used to determine the average spawning season. The ratio of mature females in coastal waters and GSI indicate that spawning occurs during June, July and August. Temperature time series in the Alboran Sea are used to calculate the length of the embryonic and planktonic phases for O.vulgaris. According to our results, individuals spawned during late spring and summer would settle during September, October and November, incorporating to the fisheries some weeks later. These results from our simple model agree with landings time series which show maximum landings from October to January or February. Keywords : Octopus vulgaris, life cycle, reproductive stages, spawning and settling, Cephalopods, environmental factors