Population structure and reproductive patterns of the NW Mediterranean deep-sea macrourid Trachyrincus scabrus (Rafinesque, 1810)

12 pages, 10 figures, 6 tables
Macrourid fish are one of the most abundant marine species on continental margins worldwide. Although they play an important role in the ecosystem, little is known about their overall biology. We report here a large data set of the most abundant macrourid in Mediterranean waters, Trachyrincus scabrus, showing the main population and reproductive characteristics. The study was based on 3,239 specimens collected between 300 and 1,500 m depth on the northwestern Mediterranean in 2003–2004 and 2008–2009. The population showed a depth-related structure with the largest individuals at 1,100 m depth and the smallest (i.e., immature) at shallower depths. Macroscopic and microscopic analyses of the gonads showed that T. scabrus has a highly seasonal reproductive pattern. Spawning females were found during winter when the organic matter fluxes were highest on the continental slope. T. scabrus is a batch spawner with group-synchronous oocyte development and present low average fecundity of 14,191 oocytes
The authors would like to thank the Officers and crews of the R/V Garcia del Cid, F/V Montse III and Virgen del Vilar for helping to provide samples and the data necessary for our study. We also thank I Quagio-Grassiotto, M Metaksakis and C Cerviño for helping with the histological analyses and JA Garcia for developing the study area map. This study was conducted within the RECS, PROMETEO and DOS MARES projects by the Spanish Science and Innovation Ministry CICYT (REN02/04556/C02/MAR; CTM2007-66316-C02/MAR; CTM2010-21810-C03-03/MAR, respectively, to JBC) and European Community’s Seventh Framework Programme under the HERMIONE project (Grant Agreement 226354, to ERLL). UF-A is funded by a Spanish PhD doctoral fellowship FPI-2008. ERLL is funded by a Spanish JAE-CSIC postdoctoral grant. This paper is a contribution number 580 from AZTI Tecnalia (Marine Research Division)