Biology of the red mullet Mullus surmuletus (Mullidae) off the Canary Islands, Central-East Atlantic

The biology of red mullet Mullus surmuletus was studied from collections taken off the Canary Islands between January 1991 and September 1993. Total length ranged from 12 to 33 cm, mainly between 15 and 21 cm. Males ranged from 14 to 26 cm and females from 14 to 33 cm. Females dominated the larger size-classes (>18 cm). The overall ratio of males to females was 1:2.3. The reproductive period extended from February to May, spawning peaking in March and April. The total length at 50% maturity was 16.6 cm for the whole population. The length-mass relationship for all individuals can be described by the parameters a = 0.0074 and b = 3.1826. Fish aged 0-8 years were present in the samples. The parameters of the Von Bertalanffy growth equation obtained for all individuals were: L-infinity = 35.71 cm and k = 0.22.year(-1). Significant differences were found in the growth parameters between males and females. The rates of total mortality Z, natural mortality M and fishing mortality F were 1.25, 0.55 and 0.70.year(-1) respectively. The estimated total length at first capture was 15.74 cm.