Sanderlings and Western Sandpipers

Most of my photos tend to be close crops of individual birds. That's primarily because of the shallow depth-of-field on my telephoto lens. Sometimes I even have trouble getting the front and back of an individual bird in focus at the same time!

On a visit to the mouth of the Tijuana River in February, 2018, I took photos of densely packed flocks of shorebirds. There were several species present, including Sanderlings, Western Sandpipers, Black-bellied Plovers, and a few Dunlins and Least Sandpipers.

This first photo is a mixed flock. The larger, paler birds in the foreground are Sanderlings. The smaller, browner-backed birds are Western Sandpipers. The very large out-of-focus birds in the back are Black-bellied Plovers. You can see that the effective depth-of-field (where birds are in focus) is barely a foot, front to back.

Sanderlings with Western Sandpipers.

Sanderlings are best known as the birds that chase the waves in-and-out on the beach like mechanical toys.

Western Sandpipers are more frequently found wading on the edge of quiet estuary waters. They may rest on the beach during high tides, if the estuaries are filled to their banks, but they won't be chasing waves looking for invertebrates at the edge of the surf.

The next photo is entirely Western Sandpipers.

A flock of Western Sandpipers.

While both these species are common in the West--sometimes in flocks of thousands--I have seen Western Sandpipers about twice as often as Sanderlings. Two factors lead to this result: 1) Sanderlings are found almost exclusively on the coast, while Western Sandpipers are equally common inland in fresh water mudflats. 2) Sanderlings are found almost exclusively on sandy beaches, where I bird less frequently because the number of other species is far less than in the more productive estuaries where I spend more of my birding time.