A Black-headed Gull (Chroicocephalus ridibundus), photographed outside St Petersburg, Russia a few weeks ago
It got its scientific name “rudibundus” which means “laughing” even though its cry doesn’t sound like laughing. The background story to the name is that when Linné named it, he used information from Ornithologia (written by Brisson in 1760) because the Black-headed gull didn’t breed in Sweden at the time so Linné wasn’t very familiar with it. In Ornithologia, Brisson described the Black-headed gull (Chroicocephalus ridibundus) and the Laughing Gull (Leucophaeus atricilla) as sub-species of the same art (Gavis ridibunda). Unlike the Black-headed gull though, the Laughing gull’s cry does sound like laughing- despite missing “rudibundus” in its scientific name.
If you only get a quick look at one of these gulls and want to know which one you saw, it might help you to know that the Black-headed Gull lives in Europe and Asia and the Laughing Gull in North and South America.