Poultry, Fisheries & Wildlife Sciences
Open Access

A Short Note on Dugong

Kamini Dev^{* *}Correspondence: Kamini Dev, Department of Zoology, Utkal University, Tamil Nadu, India, Email:

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Description

Dugongs (Dugong dugon), is commonly known as sea cows, have a large but fragmented range that extends from East Africa to Vanuatu, around 26 degrees north and south of the equator. This range encompasses at least 48 nations and over 140,000 kilometres of tropical coastline. The biggest population of sea cows may be found in Australia's northern seas, between Shark Bay (Western Australia) and Cape York (New South Wales). The second largest population is in the Arabian Gulf. Dugongs are not considered migratory animals, but they have been known to travel long distances in their range in search of food. Unlike their main freshwater cousin, the manatee, dugongs are primarily marine mammals. Dugongs usually live in shallow water and stay at a depth of about 10 m, although they occasionally dive to a depth of 39 m to feed. These shallow waters are generally found in sheltered bays, wide mangrove trails, and protected areas on offshore islands. The seagrass bed formed by seagrass is their main food source, which coincides with these optimal habitats. However, dugongs also appear in vast continental shelves, shallow seas, and protected deeper waters. Dugongs use different habitats for different activities. For example, fairly shallow tidal flats and estuaries are potential areas suitable for calving.

The dugong has a large, sturdy mammalian short paddle-like forelimb fins and a straight or concave tail that serves as a propeller. Their tails are distinct from manatees by their paddleshaped tail. Dugong fins Similar to dolphin fins, but unlike dolphins, dugongs do not have dorsal fins. A female calf has a mammary gland under its dorsal fin. Adult dugongs weigh between 230 and 400 kg and have a body length of 2.4 to 4 m. They have thick skin and are brownish-gray, and their color may change as algae grow on them. Canine teeth are present in all dugongs, but are usually only visible through the skin in mature males and older females with prominent canines. Their teeth are protruding incisors. There are no other external physical differences between the genders because they are V-shaped.

Their ears are not flaps and leaves, but they are still very sensitive. It is suspected that dugongs have high auditory precision to compensate for reduced vision. Their noses are fairly large and round and end in cracks. This fissure is a muscular lip hanging from the lower mouth, helping the dugong forage for seaweed. The dugong has a lower jaw that corresponds to the enlarged incisors. It covers the upper lip and the sensory head helps it find food. The bristles also cover the dugong's body. Every few minutes there is a pair of nostrils above the head that are used for ventilation when the dugong exposes the surface. The valve keeps the valve closed during the dive.

Reproduction

The mating behavior of dugongs varies slightly with location. For example, in a mating herd in Moreton Bay, off the coast of Queensland, males take part in aggressive competitions for females in oestrous. In comparison, dugongs in South Cove in Western Australia display a mating behavior similar to lekking. A lek refers to a traditional area where male dugongs gather during mating season to participate in competitive activities and displays that attract females. As these lekking areas lack resources necessary to females, they are drawn to the area only to view the males' displays. Male dugongs guard their territories and change their signs of behavior to attract females. After attracting a female, the male dugong goes through several stages to mate. The "next step" occurs when a group of males chases one female and tries to mate with the female. The "fighting phase" occurs after the splash consists of tail hits, rolls, and body flanges. This is likely to be as violent as seen in the scars visible on the male colliding from the female body and protruding fangs. The "boarding phase" occurs when one male ride on a female from below, with more males competing in that position all the time. Therefore, females are worn multiple times with competing males, almost guaranteeing pregnancy. Therefore Dugong is polygonal.