The reproduction of anglerfish Lophius piscatorius Linnaeus from the north‐west coast of Scotland

Abstract

The reproductive cycle of anglerfish was studied by examining fresh material obtained from commercial landings and research vessel surveys. The general morphology and histology of the gonads are described. This species has unusual gonads. The testes are tubular, and beanshaped in transverse section. The maturation process of the testis is similar to that of most other teleosts. The ovaries are confluent and form a single, flattened tube. During maturation, the width and, in particular, the length of the ovaries increases dramatically. A gelatinous matrix is produced during the maturation process, which contributes to the enormous size and weight of ripe ovaries. Ripe testes can be found throughout the year, whereas ripened ovaries were found only between November and May. Females outnumbered males in length classes greater than 70 cm and no males larger than 90 cm were found. The estimated mean length at maturity (150%) was 73 cm for females and 49 cm for males. Because only the large female anglerfish are capable of spawning, and because virtually all large anglerfish are female, trends in their abundance resulting from commercial exploitation should be monitored with care.