Contrasting extreme long‐distance migration patterns in bar‐tailed godwitsLimosa lapponica

Abstract

Migrating birds make the longest non‐stop endurance flights in the animal kingdom. Satellite technology is now providing direct evidence on the lengths and durations of these flights and associated staging episodes for individual birds. Using this technology, we compared the migration performance of two subspecies of bar‐tailed godwit Limosa lapponica travelling between non‐breeding grounds in New Zealand (subspecies baueri) and northwest Australia (subspecies menzbieri) and breeding grounds in Alaska and eastern Russia, respectively. Individuals of both subspecies made long, usually non‐stop, flights from non‐breeding grounds to coastal staging grounds in the Yellow Sea region of East Asia (average 10 060 ± SD 290 km for baueri and 5860 ± 240 km for menzbieri). After an average stay of 41.2 ± 4.8 d, baueri flew over the North Pacific Ocean before heading northeast to the Alaskan breeding grounds (6770 ± 800 km). Menzbieri staged for 38.4 ± 2.5 d, and flew over land and sea northeast to high arctic Russia (4170 ± 370 km). The post‐breeding journey for baueri involved several weeks of staging in southwest Alaska followed by non‐stop flights across the Pacific Ocean to New Zealand (11 690 km in a complete track) or stopovers on islands in the southwestern Pacific en route to New Zealand and eastern Australia. By contrast, menzbieri returned to Australia via stopovers in the New Siberian Islands, Russia, and back at the Yellow Sea; birds travelled on average 4510 ± 360 km from Russia to the Yellow Sea, staged there for 40.8 ± 5.6 d, and then flew another 5680–7180 km to Australia (10 820 ± 300 km in total). Overall, the entire migration of the single baueri godwit with a fully completed return track totalled 29 280 km and involved 20 d of major migratory flight over a round‐trip journey of 174 d. The entire migrations of menzbieri averaged 21 940 ± 570 km, including 14 d of major migratory flights out of 154 d total. Godwits of both populations exhibit extreme flight performance, and baueri makes the longest (southbound) and second‐longest (northbound) non‐stop migratory flights documented for any bird. Both subspecies essentially make single stops when moving between non‐breeding and breeding sites in opposite hemispheres. This reinforces the critical importance of the intertidal habitats used by fuelling godwits in Australasia, the Yellow Sea, and Alaska.

Sleeping on the wing

“…Red knots (Calidris canutus rufa) make flights across the Atlantic Ocean between South and North America lasting up to 6 days and spanning 8000 km [34]. However, the current record holder is a sub-species of the bar-tailed godwit (Limosa lapponica baueri) which migrates from Alaska to New Zealand, a flight spanning 11 690 km and lasting 8.1 days [35,36] (figure 2). In addition, their return migration to Alaska is completed in two long flights via a stopover in China.…”

Identical metabolic rate and thermal conductance in Rock Sandpiper(Calidris ptilocnemis)subspecies with contrasting nonbreeding life histories

“…Members of this family tend to breed at relatively high latitudes and are highly migratory, most conducting annual migrations totaling 10,000-30,000 km between high-latitude breeding grounds and temperate nonbreeding locations (Piersma et al 1996b, Battley et al 2012. Migratory shorebirds exhibit considerable phenotypic flexibility that enables efficient physiological "retooling" to accommodate these migratory behaviors Lindström 1997, Battley andPiersma 2005).…”

Acoustic monitoring of migratory birds over western Lake Erie: avian responses to barriers and the importance of islands

“…Migratory birds can fly non-stop for thousands of kilometres (Egevang et al 2010;Bairlein et al 2012;Battley et al 2012) and are likely to encounter ecological barriers, such as bodies of water, mountain ranges, or stretches of desert as they move between breeding and wintering grounds. Numerous factors might lead birds to select circuitous routes rather than cross over ecological barriers (Alerstam 2001), including their own body condition and external information such as weather conditions (Schmaljohann and Naef-Daenzer 2011).…”