Migration was a popular aspect of the existence reputation of of several avian species, however the market consequences regarding variable migration methods have only seldom started investigated, and you will barely while using the progressive scientific and you can logical approaches for determining emergency, direction patterns, and enough time-title returns in the context of existence records concept. We monitored the fates out-of fifty satellite-inserted tundra swans (Cygnus columbianus) more cuatro years of four disparate reproduction areas from inside the Alaska, and put recognized-fate analyses so you’re able to estimate month-to-month survival possibilities in line with migration distance, reproduction urban area, migratory flyway, reproduction condition, and you will age. We specifically checked whether migratory wild birds face a swap-off, whereby a lot of time-range migrants realize higher emergency cost at the expense of lower returns on account of less date on reproduction parts in line with birds you to migrate shorter ranges and you can save money date on reproduction section.
Results
Yearly migration distances ranged somewhat certainly reproduction components (1020 so you’re able to 12720 kilometres), and you will had been highly adversely synchronised over time spent on reproduction elements (roentgen = ?0.986). Estimates from yearly endurance possibilities ranged from the wintering area (Pacific shore, Alaska Peninsula, and you can East seaboard) and you will ranged out of 0.79 (95%CI: 0.70–0.88) to at least one.0, based standards always detect mortalities away from radio problems. I didn’t select research for a great linear relationship anywhere between migration length and you may survival given that swans about breeding parts on smallest and you can longest migration distances had the highest success likelihood.