Making tracks
By Jude Lane on Thursday, August 17th, 2017
One of the most exciting aspects of the field season is getting to download the data from the GPS tags and seeing where the gannets have been. As in previous years, we left the tags on for 7 to 10 days allowing us to record multiple trips from each bird.
A popular foraging location for many of the gannets this year has been the Fladen Ground, a large fishing area in the middle of the North Sea between Scotland and Norway.
This gannet made 5 trips to the Fladen Ground in 10 days, covering an average of 670 km on each journey (each trip is a different colour). To put this in perspective, this is the equivalent to you making a round trip from Leeds to Bristol for your food shop – every 2 days!
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- Five trips by one gannet to the Fladen Ground.
In complete contrast, other gannets have been staying much closer to the colony. This male only went a maximum of 35 km from Bass Rock when it went up to St Andrews, however it still managed to cover between 90 and 200 km during each of these four trips.
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- This male stayed much closer to home.
This female gannet also chose to forage close to shore but instead headed south to the coast of Northumberland. During the yellow trip she covered a distance of 375 km and spent time foraging close to Holy Island. During the pink trip she spent time foraging close to the Farne Islands in areas that shags forage for sandeels.
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- This female stuck close to shore but headed south to English waters.
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- She spent lots of time foraging around the Farne Islands.
It’s always fascinating to see the variation in foraging strategies used by gannets who are neighbours at the colony. Establishing why they have developed these individual strategies is something I and other researchers are hoping to try and understand a little better.