Elegant Terns bring ocean contaminants inland to their island colony

July 11, 2026

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have been sighted 14 times since April hunting these waters, dispersing north from Isla Rasa where nearly the entire global population nests. The birds follow fish migrations — a sensible ecology — but the fish themselves carry a hidden cost. The hunting grounds here have been formally listed as impaired for more than two decades, and no cleanup effort has been completed.

This creates a direct pathway for contaminants to reach the colony. Elegant Terns are trophic foragers; they concentrate whatever toxins accumulate in the small fish they prey on. When they return to Isla Rasa to feed their chicks, those same contaminants arrive in the food the young birds consume. The colony's resilience depends entirely on the ocean remaining relatively clean—a condition that has not held for at least twenty years.

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More about Elegant Terns

A flock of Elegant Terns roosts at Garibaldi amid warm coastal water

September 16, 2026

A flock of eleven was resting at the Garibaldi Marina on Tillamook Bay on September 11. This is a bird of the Gulf of California and the Southern California coast. More than nine in ten of them nest on a single island, Isla Rasa, in the Gulf of California, and only five nesting colonies remain in the world. Another was photographed in Tillamook County in late April, so the species turns up on this coast in more than one season. Picking one out from the that also work this bay is mostly a matter of the bill. An Elegant Tern is a slim, crow-sized tern with a long, thin orange bill that droops slightly toward the tip. A Caspian Tern is a much heavier bird with a thick, deep red bill, and in flight its outer wing feathers are mostly black from below where the Elegant Tern's are pale with dark tips. Royal Tern, scarce this far north, also has an orange bill, but a stouter one, and a short bushy crest that stops behind the eye with white between the two. The Elegant Tern's crest is longer and shaggier; it starts above the eye, wraps around it and runs down the nape. In September the adults show a white forehead rather than the full black cap of the breeding season, and young birds are grayer above with a gray crown and more mottling. Common and Forster's Terns are smaller still, with slighter bills, and neither carries the shaggy nape.