Records of ocean sunfish Mola mola along the Norwegian coast spanning two centuries, 1801-2015

J Fish Biol. 2017 Nov;91(5):1365-1377. doi: 10.1111/jfb.13456. Epub 2017 Sep 12.

Abstract

Records of the ocean sunfish Mola mola along the Norwegian coast were compiled from all possible sources: literature, media, databases and museums. A total of 216 records were found between 1801 and 2015. They were distributed along the whole coast, except for the most north-eastern part. Nearly all years with more than five records were after 2000, with 1985 as the only exception and with a maximum of 23 records in 2014. Most, 92·4%, were from July to December. Records from before 1979 were more incidental and random and no sunfish were recorded in 54 separate years between 1879 and 2015. The northernmost record was from 70° 44' N in December 1881. No relationship between year and latitude was found. Forty-four per cent of the records were of sunfish caught in fishing gear, 27% were found stranded and 30% were observed alive at sea. A trend of a decrease in numbers of observations of living individuals and an increase in numbers of strandings as dead individuals as autumn progressed was found. Geographical differences in the three categories of observation were also found. Among the specimens whose size was recorded, most were small, <30 kg and 70 cm in total length. Only 10 were heavier than 100 kg, all these were from before 1960. Annual numbers correlated weakly with sea temperatures. This was supported by a weak negative correlation with the North Atlantic Oscillation (NAO) index, because the majority of years since 2000 had a negative NAO.

Keywords: Mola mola; Norwegian coast; distribution; media records; museum collections.

MeSH terms

  • Animals
  • Conservation of Natural Resources
  • Ecosystem*
  • Norway
  • Oceans and Seas
  • Population Density
  • Tetraodontiformes / physiology*