Pacific Loons are medium-sized divers, slightly smaller and sleeker than Common Loons, measuring roughly 25 inches in length with a wingspan of 36 inches. In breeding plumage they show a smooth gray head, black throat patch with subtle purple sheen, stark white underparts, and a finely checkered black-and-white back. In winter , which We see in Arizona, the throat and foreneck fade to white, the bill appears more silvery, and overall plumage is drabber. Like all loons, their legs sit far back on the body, and they carry a dagger-shaped bill suited for underwater foraging.
In Arizona, Pacific Loons occur chiefly as winter visitors and migrants on large reservoirs and riverine lakes. The Lower Colorado River Valley is the hotspot: Lake Havasu and Lake Mohave regularly host flocks of several individuals from late fall through early spring, often numbering into double digits alongside other loon species. Elsewhere in the state they are much less predictable, but small numbers appear at other large water bodies—in fall 2024, one was present at Lake Pleasant from 28 October to 29 November.
