Gulls aren’t everybody’s cup of tea it appears however I discover them an enchanting group, extremely adaptable and able to surviving and thriving in lots of conditions. Right here, within the south-west of the Iberian Peninsula, I’m fortunate to have the ability to see a variety of gulls, notably alongside the Atlantic coast at the moment of the yr. It’s a time when arrivals from the north combine with native gulls, whereas others are getting back from the south.
The Audouin’s Gull (Ichthyaetus audouinii) is an instance of the latter. Some birds keep across the Strait of Gibraltar however the majority exit it in the summertime and head to wintering grounds of the coast of West Africa. Grownup birds begin trickling again after the moult, advance events forward of the primary entry into the Mediterranean in February.
Different Mediterranean species cling round all winter. Slender-billed Gulls (Chroicocephalus genei) match Audouin’s in class and so they stay alongside our coasts all yr. They’re by no means quite a few however are common in in favoured localities. Their numbers are overshadowed by the large concentrations of Mediterranean Gulls (Ichthyaetus melanocephalus) that make these coastlines their winter house. The gatherings, notably within the estuary of the Guadalquivir River, attain many hundred birds at anybody time. We mustn’t pass over, naturally, the massive numbers of Black-headed Gulls (Chroicocephalus ridibundus) which arrive from north-western Europe, Scandinavia and japanese Europe.
The Atlantic coast receives hundreds of Lesser black-backed Gulls (Larus fuscus) from the north. Many proceed south in direction of Morocco and past however a big proportion stay. These birds are coming from north-western Europe and Scandinavia. Right here they combine with the native Yellow-legged Gulls (Larus michahellis) which they outnumber. Curiously, as soon as into the Strait of Gibraltar and the Mediterranean the sample is reversed. It hasn’t at all times been so, although. I recall large roosts of Lesser black-backed Gulls on Gibraltar within the seventies and enormous actions of those gulls over the Rock in response to chilly climate. The decline in Lesser black-backed numbers right here coincided with the rise of the Yellow-legged Gull colony within the late seventies.
The gulls that reply most reliably to unhealthy climate, particularly Atlantic gales, are the Kittiwake (Rissa tridactyla) and the Little Gull (Hydrocoloeus minutus). Some years we see only a few however others they are often fairly quite a few as they’re pushed onto the coast and even inland, many perishing within the course of. Prior to now, we used to get giant flocks of Little Gulls off Gibraltar after easterly gales. These will need to have been birds wintering within the Mediterranean however, sadly, we haven’t detected these for a few years now.
Such climate additionally pushes in American gulls. In recent times these have included Bonaparte’s Gull (Chroicocephalus philadelphia), Laughing Gull (Larus atricilla), Franklin’s Gull (Larus pipixcan) and Ring-billed Gull (Larus delawarensis).
The image is accomplished by small numbers of Nice black-backed Gulls (Larus marinus) and Frequent Gulls (Larus canus) reaching right here the southern fringe of the wintering vary. Scarcer, but in addition common, are Glaucous Gulls (Larus hyperboreus) and, extra hardly ever Iceland Gulls (Larus glaucoides), Herring Gulls (Larus argentatus) and, more and more, Caspian Gulls (Larus cachinnans).
