Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2017
Erindi/veggspjald / Talk/poster E71
Höfundar / Authors: James Kennedy (1,2), Halldór G. Ólafsson (2)
Starfsvettvangur / Affiliations: 1. Marine and Freshwater Institute, 2. BioPol
Kynnir / Presenter: James Kennedy
Lumpfish (Cyclopterus lumpus) have an extended spawning season in Iceland with the population spawning from March until August. However, individual fish spawn only two batches of eggs with approximately two weeks between these batches. This poses an interesting question of whether the spawning time of an individual fish is random. We investigated this using tagging data of female lumpfish tagged between 2008 and 2016 during the commercial fishery. A high proportion of recaptures were within the year in which they were tagged, however, 89 fish were recaptured during the following year´s fishing season. The date in which the fish was recaptured the following year was positively correlated with the date in which the fish was tagged i.e. fish which were tagged later in the season in one year, were recaptured later in the season of the following year. As the fishery catches fish which are close to spawning, this pattern of recaptures indicates that spawning time in female lumpfish is influenced by the timing of the previous year´s spawning. This spawning time fidelity between years may in part be influenced by the extended time taken for lumpfish to develop their gonads, which takes at least 8 months. The current pattern of decreasing fishing effort as the season progresses has the potential to impact the spawning diversity of the stock as earlier spawners will have a higher likelihood of capture.