Spring migration of Northern Pintails from California's Central Valley wintering area tracked with satellite telemetry: routes, timing, and destinations

Abstract

We used satellite transmitters to track the 2000–2003 spring migrations of adult female Northern Pintails (Anas acuta L., 1758) from California's Central Valley, USA. PTT-tagged Pintails departed during late February to mid-March, and 77%–87% stopped first in the region of south-central Oregon, extreme northwestern Nevada, and northeastern California (SONEC). Subsequently, most Pintails used migration strategies characterized by the length of stay in SONEC and subsequent destinations: (i) extended stay in SONEC, migrated late April to early May directly to Alaska over the Pacific Ocean (7%–23% annually); (ii) same timing as in i, but flew to Alaska along the Pacific Coast using stopovers (0%–28% annually); (iii) moderate period in SONEC, migrated late March to mid-April directly primarily to southern Alberta in Prairie Canada (17%–39% annually), with many moving to northern Canada or Alaska; or (iv) short period in SONEC, migrated early to late March to Prairie Canada via stopovers primarily in southern Idaho and western Montana (32%–50% annually), with some moving to northern Canada or Alaska. Pintails that bypassed SONEC used these same strategies or moved easterly. Pintails modified migration strategies relative to record cold temperatures and wetland abundance in the mid-continent prairie region.