Thursday

Oology Cards set #6

I am still entering gull eggs into the data base. Today we reached the 100,000 mark in number of egg sets entered, so that's about half way.
The first gull we'll look at is the Audouin's Gull (Ichthyaetus audouinii) which is also the rarest gull I'll talk about today. It is a small gull being about the size of a Ring-billed Gull. In the 1960's the population had dropped to just 1,000 birds with the whole population found in the
Mediterranean and western coast of Saharan Africa. As of today the population is up to about 10,000 but still needs to climb higher to negate many of the risks of small population size. The gulls traditionally feed by fishing, unlike many other gulls which scavenge. Nowadays they rely mostly on by-catch from industrial fishing operations. Their current main threats are tourism, which has led to coastal development as well as disturbances during the breeding season, and its dependence on fishing operations. If the fishing stocks were to deplete further and the fisheries to close the gulls would take many generations to go back to fishing for themselves. The IUCN lists them as Near Threatened.
Our next gull is the Mew Gull (Larus canus) also known as the Common Gull. Contrary to what its name suggests this bird is not especially common, despite a large range, but instead feeds on common land during the breeding season ie. pasture land. The gulls are found throughout most of the upper parts of the Northern Hemisphere. They feed mainly on insects during the breeding season and on marine critters out of the breeding season. They also eat berries which makes them omnivorous. The birds are not currently under threat as human activities such as fishing benefit them enough to raise their numbers. The IUCN lists them as Least Concern.
Our last gull is the Herring Gull (Larus argentatus sp.). They are probably the most widely seen pink-legged gull in the U.S. and are also very common in Europe. They are so common that in some coastal areas they are considered a pest as they out compete rare shorebirds for nesting sites. The adults usually spent the non-breeding season close to the breeding site and can be found near both fresh and salt water. The gulls are vulnerable to threats such as pesticide use and oil spills, but on the whole the population is increasing. They are opportunistic feeders eating everything from by-catch to eggs to trash. Due to their large numbers the IUCN lists them as Least Concern.

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