New insights from geolocators deployed on waders in Australia
journal contribution
posted on 2013-04-01, 00:00authored byC Minton, K Gosbell, P Johns, M Christie, Marcel KlaassenMarcel Klaassen, C Hassell, A Boyle, R Jessop, J Fox
Geolocators were deployed on waders in Australia for a third successive year, in Feb/Apr 2011 including on Eastern Curlew and Sanderling for the first time. Retrieval rates, in the 2011/12 austral summer, varied markedly between species. Technical performance of the geolocators was better than in previous years. However units on Greater Sand Plovers, migrating to breeding grounds in the Gobi Desert, China/Mongolia, again behaved erratically, and exhibited symptoms suggesting extraneous electromagnetic interference. Generally, for each species studied, the results confirm earlier indications that the first step of northward migration from Australia is a long non-stop flight. Subsequent movements to breeding areas are usually shorter with up to three stopovers in SE Asia or Siberia. Similarly southward migration strategies include at least one long nonstop flight, though this is usually the second (or later) leg of the journey. The timing of migration appears to be particularly related to breeding latitude. Eastern Curlews, which breed at relatively southern latitudes, depart from SE Australia from early March, reach the breeding grounds and lay eggs in April, set off on return migration in early June and, after a long stopover in the Yellow Sea, arrive back in SE Australia in early August. In contrast arctic-breeding Ruddy Turnstones do not depart from SE Australia until mid/late April and do not arrive back at their non-breeding locations until October, with the last individuals (which have taken a trans-Pacific route) not returning until late November/early December. Recorded migration speeds (assuming the birds take a great circle route) were quite variable, ranging from 32 to 84 km/h, presumably due to wind conditions. They generally averaged nearer to 50 km/h rather than the 60–70 km/h which waders are known to be capable of achieving and which has been the basis of some past flight range calculations.
History
Journal
Wader Study Group bulletin
Volume
120
Pagination
37-46
Location
Norfolk, Eng.
ISSN
0260-3799
Language
eng
Publication classification
C Journal article, C1.1 Refereed article in a scholarly journal
Copyright notice
2013, National Centre for Ornithology, International Wader Study Group
Issue
1
Publisher
National Centre for Ornithology, International Wader Study Group