The appearance and living habits of seagulls

Morphological characteristics of seagulls:

1, Stephane: the head and neck are white, and the back and shoulders are slate gray; The feathers on the wings are also slate gray, the same color as the back; The waist and tail feathers are all pure white. 1 and No.2 primary flight feathers are black with large white secondary spots, and the base is gray or the inner cavity forms large gray spots; Other primary flight feathers are gray, and each feather has black secondary end spots from wide to narrow, and white end spots from small to large from outside to inside; The black secondary end spot of the internal primary flight feather disappears, leaving only the white end spot; The second and third flight feathers are slate gray with wide white spots at the end. The lower body is pure white.

2. Winter feathers of adult birds: Similar to Stephane, there are only light brown spots on the top of the head, the side of the head, the pillow and the back neck, and the spots are sometimes arranged in vertical stripes on the pillow and in horizontal stripes on the back neck.

3. Young bird: the upper body is roughly white with light brown stripes; The tail is covered with white feathers with brown transverse spots, with grayish brown tail and white base; The primary flight feathers are dark brown, the other flight feathers are brown, and the edges are pale white. The tail feathers of sub-adult birds are white with broad black secondary spots, and the secondary and tertiary flight feathers are light gray with brown spots.

4. The iris is yellow; Mouth, feet and toes are light green and yellow; Young birds have brown iris, pink or light brown mouth, similar to adult birds in winter, and all have black secondary spots; Feet are flesh-colored.

5. Size measurement: weight 394-586g；; Body length ♂482-5 10mm, ♀ 451-470mm; Mouth peak 35-51mm; Wing ♂362-388mm, ♀ 360-372 mm; Tail135-150 mm; Tarsometatarsal 51-55 mm. (Note: ♂ male; ♀ Female)

Living habits:

Seagulls feed on coastal insects, mollusks, crustaceans and worms and grubs in cultivated land; They also prey on small fish on the shore and pick up leftovers discarded on the shore and on ships. Some large seagulls prey on eggs and young birds of other birds (including their own kind). [2]?

Seagulls are the most common seabirds. In the coastal areas, seaports and fishing grounds rich in fish and shrimp, flocks of seagulls float on the water, swimming, foraging and flying at low altitude, and like to cluster in food-rich waters. In addition to eating fish, shrimp, crabs and shellfish, seagulls also like to pick up leftovers discarded by people on board, so seagulls are nicknamed "harbour cleaners". Ports, docks, bays and ships are almost frequent visitors. On the ship's route, seagulls will follow, and even walking on the beach at low tide will wake up a group of seagulls.

Seagulls are also "forecasters" of maritime navigation safety. Sailing on the sea by boat often leads to stranding or stranding due to unfamiliarity with the water environment, or shipwrecks due to sudden weather changes. Experienced sailors know that seagulls often land around shoals, reefs or reefs, and flocks of seagulls fly around and make noise, which is undoubtedly a signal to navigators to avoid collision with reefs; At the same time, it also has the habit of flying in and out of the port. Whenever navigation is lost or foggy, observing the flying direction of seagulls can also be used as a basis for finding ports.

In addition, if seagulls fly close to the sea, the weather will be good in the future; If they wander along the seaside, the weather will get worse gradually. If seagulls leave the water and fly high, flying from the sea to the seaside in droves, or flocks of seagulls gather on the beach or in cracks in rocks, this indicates that a storm is coming. Seagulls can foresee storms because their bones are hollow and tubular, and they are filled with air without bone marrow. This is not only convenient for flying, but also like a barometer, which can predict the weather changes in time. In addition, the hollow feather tubes on seagulls' wings can feel the change of air pressure sensitively, just like a small barometer.