NWO TOP grant.
New avenues for studying long-distance migration
Since the distribution of shorebirds searching for their prey is highly dynamic in time and space, monitoring of bird movements over vast areas has so far been a major challenge. Satellite tracking appears to be the way forward, but this approach was so far only feasible for relatively large birds which could easily carry the additional weight of the tags. Innovative lightweight tags are now yielding the first maps on the movements of relatively small shorebirds.
A first test with red knots
On 3 October 2013, ten tag-carrying red knots were released on Texel. In their search for prey (in particular the small bivalve Macoma balthica) and safe foraging areas, most birds started to move throughout the international Wadden Sea region whilst one individual flew to the Wash in England. Interestingly, the young birds moved furthest away from the release point, possibly because they still had to monitor the distribution of their food sources.
A mental picture?
Adult shorebirds, such as red knots, may perhaps rely on a mental picture of good foraging areas which they build up during the first phase of their lives.