SIGHTINGS of basking sharks have been at the lowest level in at least five years.
With the basking shark season now at an end, there have been just 291 sightings reported to the Manx Basking Shark Watch website this year. This is significantly fewer than the 414 sightings last year and the 835 sightings in 2009.
Manx Basking Shark Watch had 564 sightings in 2008, 677 in 2007, and 506 in 2006. There were only 159 sightings reported in 2005, but this was before the website was fully up and running.
Eleanor Stone, marine officer for the Manx Wildlife Trust, said the lack of sightings was likely to be no more than a ‘blip’ and should not give cause for concern.
A lack of surface plankton, due to a shifting tidal front, has been blamed for the low number of reports over the summer – with the suggestion that the sharks could have headed to Scotland instead.
But Eleanor said it may simply be that sharks, which are the second largest fish in the world and a regular visitor to Manx waters, have been here but were just deeper and so could not be seen.
She said: ‘Although there are still a couple of sightings coming in, the season does seem to have to come to an end for 2011.
‘May and June didn’t start too badly, but July and August were particularly low on sightings.
‘Although we don’t know for sure why this is, there was a distinctive lack of plankton at the water surface, throughout the summer. We have no way of knowing whether the sharks were in fact here, just deeper in the water where they couldn’t be spotted.
‘Despite the lack of sharks, we still managed to achieve some scientific research. Three satellite tags were deployed, which will tell us where the sharks travel to over the next few months, and more photos and genetic samples were collected, which will allow us to distinguish between individual sharks.
‘Good and bad years come and go in nature, especially when trying to observe a highly mobile species that is only visible when at the water surface, so we would not draw any firm conclusions from this season’s lack of sightings.
‘We’ll keep our fingers crossed that next year will be back to “normal” and there will be a lot more sharks out there for us all to spot!’