An ovigerous Maja spider crab was captured during a fishery research cruise in the North Alboran Sea, western Mediterranean, near the city of Malaga. From morphological characters this individual was identified as Maja brachydactyla. Prior to the specimen being returned alive back to sea, it was measured, photographed, and a portion of a pleopod excised for genetic analysis. The latter confirmed the identification as correct. An additional seven specimens collected from Caleta de Velez in the vicinity of Malaga were morphologically examined, confirming the presence of M. brachydactyla in the Alboran Sea. This finding would represent the first evidence of the species occurring in the western Mediterranean Sea, with apparently well-established populations.

The Magharees fishery (Brandon and Tralee Bays in south-west Ireland) is 495 km2 in extent, the majority of this area ≤20 m in depth. Since 1981 it has been occupied by a directed spider crab fishery yielding in some years all of the national catch of Maja brachydactyla. Maximum recorded landings were 336 t in 1999 and effort has numbered up to 10,000 pots annually. Increasing fishing capacity and declining opportunities have accentuated fishing effort on spider crab. This paper describes a catch census undertaken in the fishing season of March to August inclusive, 2000–2007 and a mark–recapture experiment, 2005–2007. A method of ageing the adult moult by attributing a chronology to the rate of erosion of the claw on the dactyl is introduced. Males migrated longer distances, moved into the fishery on a wider trajectory and demonstrated greater wear on the claw than females. Recapture rate of males was twice that of females. The conduct of the fishery changed in its 26 years in existence. Landings became more concentrated in the earlier months of the year and the recent summer fishery was characterized by fewer male captures. Larger males were quickly removed and none >140 mm carapace length survived in the fishery longer than one year.