Galapagos Marine Iguana

Galapagos marine iguana is the only sea-going lizard in the world.

This reptile lives on rocky coasts, feeding on seaweed, and can remain underwater for up to 45 minutes.

The scientific name of the marine iguana is Amblyrhynchus cristatus.

The name is derived from the characteristically blunt snout, which allows the marine iguana to scrape algae off of the rocks with their razor sharp, three-cusped teeth.


 

The Galapagos marine iguana feeds almost entirely on algae (seaweed) that is found between the tide-lines or below the sea's surface. The food consists of small red or green algae.

Marine iguana eats most of the algae species, except the large brown seaweed Blossevillea. This is indigestible for the marine iguana.

Marine iguanas are widely distributed throughout the islands. Although the different populations vary in size and color, they are all considered to be a single species.

The smallest Galapagos marine iguana is found on Genovesa island, and some of the largest iguanas are on Fernandina and Isabela islands. Espaņola island shows the most differentiated, colorful marine iguanas.

These iguanas have blotches of coppery green and red. The red pigment comes from a particular seaweed that blooms during the summer months, which also coincides with the iguanas' mating season.

Marine iguana in Galapagos eats once a day, but some of the larger ones will feed only every second or third day.

The pattern of daily activity is largely determined by the temperature and the state of the tide.

The larger males will usually wait until the middle of the day when the sun is at its hottest and they have had time to warm up before they will swim offshore and start diving to feed.



The rest of the population leaves the colonies a little before the tide has reached its lowest ebb and feed on the shoreline.

As I said before, the Size is different amongst Galapagos marine iguanas, it depends mainly on the island it inhabits.

Marine iguanas have a variety of physical characteristics that permit their unusual feeding habits. The Galapagos marine iguana has incredible swimming abilities.

Their tails are flattened and they swim by lateral undulation of their bodies, with their limbs held to the side.

Their claws are long and sharp in comparison to the Galapagos land iguana that enables them to cling to rocks along the shore, and resist being pulled away by heavy waves.

Adult iguana male's coloration varies with the season. Breeding-season adult males on the southern islands are the most colorful and will acquire reddish and teal-green colors, while on Santa Cruz they are brick red and black, and on Fernandina they are brick red and dull greenish.

Only the largest males dive because larger animals have proportionally smaller body surface areas than smaller animals and are therefore more resistant to the loss of body heat at the surface.

As an ectothermic animal, the Galapagos marine iguana can spend only a limited time in the cold sea, where it dives for algae.

However, by swimming only in the shallow waters around the island they are able to survive single dives of up to half an hour at depths of more than 15 mts.

After these dives, they return to their territory to bask in the sun and warm up again.

The marine iguana from Galapagos can shunt blood away from the surface to conserve heat, and they can drastically reduce their heart rate.



It is important to note that two parts of the same population have different activity cycles.

More About Galapagos:

Recommended Galapagos Reading

Wildlife of the Galapagos (Princeton Illustrated Checklists)
Wildlife of the Galapagos is the most superbly illustrated and comprehensive identification guide ever to the natural splendor of these incomparable islands. It really reveals the archipelago's striking beauty. (A well-written, informative text).

More Galapagos Books and Souvenirs

Web www.galapagos-islands-tourguide.com

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