STUDY OBSERVES BASKING SHARK COURTSHIP BEHAVIOUR
Basking sharks may be using the shallow waters around the Western Isles of Scotland and around Cornwall as mating grounds during the summer months, a large-scale tagging study reveals
The report reveals that the basking shark population divers see around the Isles of Hyskier, Coll and Tiree in the Hebrides see each year stay within the area during the summer months with some of the population moving off in the autumn as far as the coast of Morocco in North Africa. Some stay close to Scotland all year.
The study by Scottish Natural Heritage working with the University of Exeter tagged a number of sharks during the summers of 2012, 2013 and 2014. The scientists also closely observed the sharks during the summer months and recorded behaviour suggesting courtship.
The report stated; ‘During fieldwork a range of basking shark behaviour was observed, most intriguing were; nose-to-tail following, lateral approaches and breaching. These behaviours have previously been attributed to courtship display.’
In total 61 tags were attached - 21 to females, 13 to males and 27 to basking sharks on unknown sex. The sharks ranged in size from 4m to 9m - with the range of 5-6m being the most common.
The study shows that the Irish and Celtic Seas are an important migration corridor for basking sharks moving between the Sea of the Hebrides, the Isle of Man and southwest England.
The tagged sharks dispersed widely in the autumn, moving to the west of Ireland, the Bay of Biscay, Iberian Peninsula and North Africa. Some sharks, however, remained relatively close to Scotland throughout the winter.
It also revealed that in the winter months some of the sharks frequently dived to depths below 1,000m.
The report argues that the hotspots for sighting of basking sharks could well be crucial to conserving the species and should be protected zones.