Movements of female lumpfish (Cyclopterus lumpus) around Iceland

Abstract

Lumpfish (Cyclopterus lumpus) migrate from their offshore feeding areas to the coastal areas of Iceland during March and April where they remain for several months before spawning. Their movements during this time are poorly documented. Using the results of an extensive tag-recapture study (the largest documented for lumpfish) which took place between 2008 and 2014, the movement of female lumpfish around Iceland was investigated and the implications for fisheries management were considered. Of 9710 female fish tagged, 880 were recaptured and 82 of these were recaptured after more than 250 days at liberty (DAL). There was a negative relationship between length at tagging and recapture rate indicating that between 2008 and 2014, the fishery was selecting for smaller fish. Lumpfish showed extensive movements with fish tagged in coastal areas being recaptured up to 587 km from their tagging location and were capable of swimming up to 49 km day−1. Fish were most frequently caught in the area in which they were tagged; however, movement between areas was common. There were indications of homing behaviour with 75% of the fish, which were recaptured after 250 DAL, caught within 80 km of their tagging location. Fish which were tagged offshore before the fishing season showed no clear pattern of where they would be recaptured. These extensive movements and homing behaviour are discussed in the context of the management of the lumpfish fishery.

Observations of vertical movements and depth distribution of migrating female lumpfish (Cyclopterus lumpus) in Iceland from data storage tags and trawl surveys

“…This indicates that lumpfish are capable of freeing themselves from gillnets. As lumpfish have tough skin and lack scales, they are less likely to be damaged by the net compared with other species, and results from tagging studies, which used gillnets (Kennedy et al, 2015), show that they are capable of surviving this experience. Fish 730 appears to get caught in a net on the 17.3.13, 3 d before the start of the lumpfish fishing season so this is likely to have been in a gillnet used for targeting cod.…”

“…After tagging, the fish were returned to the tank and if deemed to be in good health, released. Previous tagging experiments on lumpfish in Iceland indicate a high recapture rate (23%) of fish tagged with Peterson disc tags during the IGFS in the fishing seasons which starts soon after the survey (Kennedy et al, 2015).…”

“…The optimum balance between the frequency of depth recordings, and total recording time when tagging lumpfish with DSTs, is also considered. This paper does not discuss the horizontal movements of the fish with regards to their migration as this is addressed in greater detail along with other tagging data in Kennedy et al (2015).…”

“…In general, the targeting of lumpfish is only permitted during 15 weeks of the year, thus the majority of tags will be expected to be returned within this period. A preliminary study in 2012 tagged 94 fish with Peterson tags during the IGFS and achieved a return rate of 23% within two months of tagging, but to date, no other tags were returned after those first two months (Kennedy et al, 2015). Of fish tagged during the fishing season, only 0.8% of tags were returned after more than 250 d at liberty; however, this low return rate is likely to have been affected by rusting of the nickel pins (Fréchet et al, 2011;Kasper et al, 2014;Kennedy et al, 2015).…”

Genetic structure of West Greenland populations of lumpfish Cyclopterus lumpus

“…Currently, Greenland and Iceland are the main contributors to landings ( c . 45% each), followed by Canada and Norway (Kennedy et al ., ). In 2015, roe landings were c .…”