The season for winter migrants was over in the San Francisco Bay. Scoters, gallinules, and other birds that came for the winter began disappearing from the reed marshes and pools. Now very few birds there, among them Mallards, a pair of Gadwall, and a few grebes, including Pied-billed and Western.

In the mudflats there was a large grass-covered island, which situated a large Cackling goose, which was nearly as big as the island itself. However, there were two black-and-white birds that happened to be resting nearby. When I looked at the photo that my dad took of them, they had a orange-and-black bill, and the upper bill was shorter than the lower bill. This could only mean that it was one bird – the Black Skimmer.

The San Francisco Bay is the northernmost range for this species of skimmer, which can be found year-round in the bay. The ones I saw were beginning to molt into their summer breeding plumage.

The Black Skimmer may look like a tern from far away, however, look for the length difference between the lower and upper bills.

It uses its peculiar bill for its hunting technique. When hunting for fish, it uses it bill to cut through the water. When the bill touches anything solid, it snaps shut, catching any fish in the process. However, this technique has problems. If there is some wood in the water, the skimmer may mistake that for fish, and that is the cause for many skimmers to have broken bills.