Crocodile Bay, the largest crocodile in the world

Bay crocodile, also known as estuary crocodile, saltwater crocodile and Malay crocodile, is famous for the battle of Langli Island at the end of World War II, so it is also known as man-eating crocodile. It is located at the highest level of the wetland food chain, the largest of 23 crocodiles and the largest reptile in the world. It is also called "crocodile" because it is the only crocodile without large scales at the back of its neck. Naked-necked crocodile? . Crocodiles in the bay have a sense of territory and a physiological structure that adapts to high salinity water. China has taken action to revive crocodiles that have been extinct in China for thousands of years, and crocodiles have no subspecies differentiation.

gross feature

Adults are generally 3 ~ 6 meters long, the longest can reach more than 7 meters, and the largest weight exceeds 1600 kg. It is the largest reptile in existence. Kiss: the kiss is narrow and long, with a low front beak and obvious etching on the back of the kiss. There is a bone ridge in front of each eye that tends to kiss the end, but it is not connected with each other. Nose: a single external nostril, opening at the snout; There is no nasal septum in the nasal passage, and there is a palatal sail at its rear end without transverse fold. Eyes: The eyes are large and oval. Iris is green, with upper and lower eyelids, transparent iris, iris gland and lacrimal gland. Ear: The ear hole is behind the eyes, as narrow as a crack. Teeth: When occluding, the mandibular dentition is staggered and cut on the same vertical plane as the maxillary dentition. Head: there is no occipital scale behind the head, and there is no occipital scale behind it. Neck: There is no obvious difference between neck and head and body. The hashed neck scales at the back of the neck form a square with 1 slender bone scales on the left and right. Trunk: The trunk is long and cylindrical, which is five times that of the head. The abdomen is pale white, and the scales at the rear edge of the limbs are serrated. Back: The back is dark olive or brown, and there are about 65,438+06 rows of scales on the back. Six rows of scales on the middle back are ridged and do not become rings, and the outermost 65,438+0 rows of scales are separated from the edge to form two rows of rings. Tail: The tail is thick and flat, longer than the sum of the head and body, and can be used for powerful attacks. Limbs: the limbs are stout, the hind limbs are long, the fifth toe is short, the toe bottom is webbed, the outer toe is webbed, the inner two toes are webbed, and the inner three toes have claws.

distribution range

Crocodiles are tropical and subtropical species. It is native to Southeast Asia such as Thailand and Malaysia, and also distributed in India, mainly from Southeast Asia to northern Australia and the coastal areas of Papua New Guinea.

living environment

Crocodiles are suitable for living in different wetlands, such as estuaries, mangroves, swamps and other coastal and intertidal zones. This species is more tolerant of seawater than ordinary crocodiles.

Living habits

eating habits

Crocodiles in the Gulf feed on big fish, mud crabs, turtles, monitor lizards and birds, and also prey on wild deer, bison and wild boar. The largest individual can bite the hard armor of a turtle and the bones of a bison in one bite, and is one of the most powerful creatures in the world.

Territorial consciousness

Male crocodiles monopolize the territory, driving away invaders, and a male leads a group of females. Adult crocodiles are often underwater, with one eye and nose above the water. Sharp eyes and ears, frightened, immediately sink. In the afternoon, there was a lot of floating water to bask in the sun, and at night, anger burned, and the young crocodile was red.

Growth and reproduction

The mating season lasts several hours from May to June, while fertilization lasts only 1 ~ 2 minutes. It depends on the region: Thailand breeds lay eggs in July and August, and Java breeds can even see crocodile eggs in February. Crocodiles in the Gulf use saprophytes to nest on a tree-lined hill about 4 meters by the Danshui River, and sweep a platform of 7-8 meters with their tails. Build a nest with a true diameter of 3 meters on the platform, and lay 20-90 eggs at a time, with an egg diameter of 80? 55 mm. Female crocodiles guard the nest, always wagging their tails to sprinkle water on the nest, and keep the temperature at 30 ~ 33℃. It usually takes 75 days (Java) to 96 days (Sri Lanka) to hatch young crocodiles. The hatched crocodiles are 240mm long, 1 480mm a year, 3 years 1 156mm, and weigh 5.2kg ... fierce and unruly.

Demographic situation

Wild alligators are protected in most countries, but the effectiveness of protection in some countries is questionable. Internationally recognized as the best protected areas are Papua New Guinea and Australia, where wild populations are in a state of sustainable utilization and growth. At present, Indonesia is testing and implementing a conservation management plan similar to those of the above two countries. In addition, the number of crocodiles in artificial bays is rising sharply, especially in Southeast Asian countries. [4] IUCN Red List of Endangered Species-Vulnerable or Near Endangered (Version 2.3)