Herring Gull vs Glaucous-winged Gull
Larus argentatus versus Larus glaucescens
Play a quiz with Herring Gull and Glaucous-winged Gull
Herring Gull
Glaucous-winged Gull
These two are often mixed up in quizzes. Look at the photos, then practise the pair until the field marks stick.