Walking along Morro Strand I hear high-pitched screeches in the sky. I turn and see a cluster of terns wheeling onto shore. Sixty or more settle their white bodies onto the sand. Binoculars raised, I check out the bill size and dark heads. Are they Elegant Terns or Royal Terns? Both are winter visitors to our shores. I study carefully and check out whether the eyes are within the dark cap on the bird’s head or outside in the white face. It’s a subtle difference. Then I check out the bill size—chunky and orange for the Royals and a more slender long bill on the Elegants.
Often a group may be a mix of the two. That makes identifying easier. The Royals have a larger body along with that heavier, thicker bill. Check out the photo below to get an idea of how body and bill size along with the position of the eye distinguishes the two species. It’s subtle!
Marlin Harms has captured the two species side by side. Look at overall body size, bill size and whether or not the eye is located within the black cap or outside. If you guessed the Elegant Tern is on the left and the Royal Tern on the right give yourself a pat on the back.
And maybe you could care less which is which! As they raise their crests up and down, these large, noisy terns are just fun to watch. Who says birds don’t show attitudes?