Differences in Prevalence of Multiple Paternity in the Spiny Spider Crab Maja Brachydactyla in Two Localities That Differ in Female Fecundity, Fishing Intensity, and Management Measures

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] Many marine species are under high fishing pressure, which can cause alterations in their mating systems and the structure of their populations. The spiny spider crab Maja brachydactyla is a commercial decapod on the east Atlantic coast. In Galicia, the most exploited region in Spain, the landing of ovigerous females is prohibited, favouring exploitation focused on males. The removal of males, especially the largest ones, may lead to sperm limitation and a reduction in the average size over generations. In these cases, polyandry can work as a mechanism to protect females against sperm limitation and to increase genetic diversity and effective population size. This study analyses the multiple paternity in M. brachydactyla in two localities that differ in female fecundity, fishing intensity, and management measures. Our results showed multiple paternity in this species for the first time, with a moderate bias between sires. However, the frequency of multiple paternity was almost seven times higher in the intensely exploited Golfo Ártabro (NW Spain; 69%) than in Carna (W Ireland; 10%), where exploitation levels and female fecundity are lower.This work was funded by a CTM2014-53838-R grant from the Spanish Government (Ministerio de Economía y Competitividad), by a GRC2014/050 grant from Xunta de Galicia (Programa de Investigación Competitiva do Sistema Universitario Galego, Modalidade de grupos de referencia competitiva: Grupo de Investigación en Biología Evolutiva), and by a PID2019-109194RB-I00 grant from the Spanish Government (Ministerio de Ciencia e Innovación). The researcher Elba Rodríguez-Pena was supported by the Axudas de apoio á etapa predoutoral from the Xunta de Galicia (Spain), co-financed by the European Social FundXunta de Galicia; GRC2014/05