Australian herpetologist Harold Cogger gives a total length of 100 cm for Australian specimens. The tail is almost twice the length of the body and laterally compressed to aid in swimming. Like the rest of the lizard's body, it is covered with small, oval, keeled scales. This monitor has the ability to increase the size of its mouth by spreading the hyoid apparatus and dropping the lower jaw to eat large prey, a process similar in appearance to that of snakes, although the jaw of the mangrove monitor remains rigid. The mangrove monitor possesses a Jacobson's organ, which it uses to detect prey, sticking its tongue out to gather scents and touching it to the opening of the organ when the tongue is retracted. The mangrove monitor is one of only two species of monitor lizards that possess salt-excreting nasal glands, the other being V. semiremex, which enables them to survive in saltwater conditions and to consume marine prey. The presence of this gland probably enabled the monitors to reach new islands and aid in its dispersal throughout the Pacific. Diet The mangrove monitor is an opportunistic carnivore, feeding on the eggs of reptiles and birds, mollusks, rodents, insects, crabs, smaller lizards, fish, and carrion. Mangrove monitors are the only monitor capable of catching fish in deep water. In some parts of its range, it is known to eat juvenile crocodiles. Reproduction Males fight for females, and in one observation, after mounting the female, the male used his chin to rub the dorsum of the female's head and forequarters. While mounted and oriented head to head, the male and female slowly rotated in a clockwise direction through 360°, with the male remaining superior. Female mangrove monitors lay two to 12 eggs that measure 3.5 to 5 cm in length. The oblong eggs are white, and hatch in about seven to eight months. The first successful captive breeding of this species was at the Philadelphia Zoo in 1993. The Reptilian Zoo in Vlissingen, the Netherlands, was reported to have successfully hatched eggs by a female animal which was not in any contact with a male of the same species. Contact with humans Humans have introduced the mangrove monitor to a number of Pacific Islands since the 1930s. They have been present on Ifaluk in the western Caroline Islands since the Second World War. The Japanese introduced the lizards to the Marshall