“Land Ahoy!” this used to be the ancient mariner’s call on spotting the hovering gulls. Sea gulls are shore birds. Mariners of the past who sailed on their ships in search of new lands looked to the gulls. When they spotted gulls, they were sure that the land was not far away.
Gulls are found all over the world including Arctic, the Antarctic and up to a height of 16,400 feet in the Andes. No other bird species is this ubiquitous.
Male and female gulls are similar in color. The male gull has to make aggressive calls and put up displays to attract females. A female in search of a mate may respond to these calls. But the females will spend a considerable time in several male territories before she chooses one and gets close. When a male and a female meet in a place, the place is called a ‘pairing territory”. The pair will now leave for a nesting territory, where they will mate and build a nest.
Mew gulls and Herring gulls after choosing their nesting site wait until the surrounding ice has melted. They then build the nest. This is to prevent the Arctic fox from finding the nests and steal eggs. Gulls are open nesters on the shores. The female lays three eggs and incubates them by spreading its webbed feet on the eggs and sitting on them. Incubation begins immediately after the first egg is laid.
After the eggs are hatched, the common black-headed gull removes pieces of shells from the nest to make the nest location less conspicuous to predators. Both the parent gulls guard the nest and will not allow any intruder into the nest area. Any offender will receive a sharp jab. Even the chicks will puff out chest, open their wings and croak a shrill protest. If the intruder does not budge, the chicks will charge and display threatening gestures. The parent birds and the chicks together will form a sizeable flock to scare away even a larger predator.
Gulls feed the young by regurgitating a pile of food in front of the chicks. The parent birds will ensure that the chicks move out of the nest and pick up their food. In open nests, chicks cannot stay too long and depend upon parents. The earlier they leave the better are their survival chances. The parent birds in the meanwhile have to get ready for their migration.
Migrating Laughing gulls come in large numbers to the areas around John F.Kennedy airport in New York. Authorities have to kill thousands of these birds to prevent them from colliding with airplanes. This is inevitable and there are enough gulls in the world to be sacrificed, if man wants to fly safe.
Many gulls have a red spot on their bill. Scientists have no clue as to the actual significance of this feature.
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