Land iguanas stay on trees and remain on top to bask in the sun and normalize the temperature of their body. They are similar in appearance and could be confused as common lizards if not for their somewhat larger size. Such lizards who live in the tree are athletic and strong swimmers. These most often live on trees where a body of water is close. Water is always their refuge as predators attack them. We even transfere from one position to the other as quick movers. They may be seen sometimes crossing a road. click to read more
Nevertheless, the Marine Iguana (Amblyrhynchus cristatus) did not move as easily but they are stronger swimmers and sit in the coastlines of seawater as their habitat as they rely on algae feeding. Only on the Galapagos Islands can the iguana be located The whole coastline is populated by marine iguanas. The ability to live and forage in the sea is exceptional to modern lizards. It has spread throughout the archipelago to all the reefs, and is sometimes called the Marine Iguana of Galapagos. It stays on Galapagos coastal cliffs and is evident in marshes or mangrove beaches.
Amblyrhynchus cristatus is mostly black but it has a lighter color and a dorsal stripe for the young. Adult specimens are shown in greyish color. Scientists clarify that there has to be dark black marine iguanas emerging from mud. We feed nearly exclusively on the aquatic algae. That they are built to remove salt by nasal glands is smart. The salt coating which was removed may turn their faces white. Adult males vary in colour depending on season. In the West, male adults show as reddish and teal-green shades during the breeding season, while it is brick red and black on Sta Cruz Island and brick red and greenish on Fernandina Islands.
According to their home islands the marine iguanas live in the Galapagos vary in scale. Those on the islands of Fernandina and Isabela are the largest while those on the island of Genovesa are the lowest. The length of adult males can be up to 1.3 m long while females could be around 0.6 m long. They could weigh as much as 1.5 kg.
In fact, marine iguanas can vary in size based on the different food conditions. Once algae declined during an El Nino for a period of two years, their length size fell to as much as 20%. When the stock of food was regulated their lengths returned to normal level. During those times of food shortage their bones are assumed to shorten.
The aquatic iguana can only live in water for a limited period when it comes to fishing for algae, as they are cold blooded creatures. Nevertheless, if they are searching for food in shallow waters, they may stay underwater for up to half an hour. We return to the shore after each swim, then relax under the sun to normalize body temperature. The marine iguanas seem to get more violent while cold. Essentially that is their defense mechanism because in fact they can not move fast to avoid predators because their body is frozen from underwater. So when someone threatens them they get angry.