Galapagos Marine Iguana
GALAPAGOS MARINE IGUANA
Description
When most of us think of marine reptiles, Lizards are the last thing that comes to mind. Yet the Galapagos Marine Iguana is one that lives both in the water and on land. They are mainly designed for being in the water though. For example they are avid swimmers, they have dorsal fins, and they have webbed feet.
They have been documented diving as much as 30 feet into the ground. They do so in order to feel safe and to find food. They are shy and timid so if humans are in the water around them they will likely go deeper to get away from them. They blend into the water easily due to the dark shades of gray and black on their bodies.
These dark colors are believed to help them with being able to absorb a great deal of sunlight. They need it to help them keep their body temperature higher. In fact, if they spend too much time in the water it drops and that causes them to swim very slowly. They have to balance their time between land and in the water to stay in sync.
Even though they are believed to be timid, they tend to give off a different view by their appearance. The Galapagos Marine Iguana is covered with spikes along the head and all down the spine. The size ranges of the genders is an excellent way to be able to tell them apart. Most species of Lizards don’t have such differences.
The males may grow to a size of up to 5 ½ feet. The females are typically around the area of 3 ½ feet. You will notice that the girth of these Lizards varies by season. In the spring and summer they tend to be much wider – up to 25% more. They feet heavily due to the abundance of food. They will store up fat in their tails that they can live on in the fall and winter when they can’t find as much food.
Evolution
The fact that the Galapagos Marine Iguana has webbed feet and dorsal fins has led many experts to believe that this Lizard was once fully aquatic. What happened then that make it also rely on land for survival? Others will debate this topic though that they were once only land creatures and then due to changes on Earth they evolved to get the marine life features for survival.
While we have information that verifies Lizards have been around for at least 200 million years, there is little information to really tell us more than that. They have branched off into more than 3,800 species and that makes it tough to trace all of the lines back to their place of origin.
With many theories out there about evolution and the Galapagos Marine Iguana it is interesting to listen to the different views that people have about it. Only time will tell though if we will some day have the answers to all of the impending questions.
Behavior
Even though the Galapagos Marine Iguana is known to be mild natured, studies show that they can be aggressive. One of the reasons for it is when their body temperature dips too low. They will become agitated then and have to spend more time in the sunlight.
In order to help them stay moving quickly they need their body temperature balanced. As a result will spend large amounts of time on the shore enjoying the sun. They even tilt their head in an effort to get more of it to their bodies.
Habitat and Distribution
The Galapagos Islands is home to these Lizards so if the name of them was once puzzling to you now you know where it comes from. They may be living all over the shore along this region. That includes those swampy areas and even the beaches where humans continue to spend time as well.
Diet and Feeding Habits
Most people would guess wrong about the diet for the Galapagos Marine Iguana. It is understandable though since they do feature very sharp claws and teeth. However, they don’t eat meat at all. Instead, they consume algae and seaweed from the water and along the rocks. With a flat nose they can get very close to the rocks and even into crevices. They use the teeth and claws to be able to scrape the algae off the rocks.
One of the fascinating things about this eating process as it would seem that the Lizards are taking in too much saltwater. What studies have shown though is that there are glands that allow that saltwater to be excreted from the body as the Galapagos Marine Iguana feeds.
Reproduction
The males are very deliberate about their territory and maintaining it. They also have many females that overlap in that region with them. They will allow it as long as food is accessible. They won’t tolerate males coming into their territory though. Fighting is a big part of the mating process. The males will fight over who will be able to mate with a female.
Once a female finds a male that is strong enough to keep the others away she is very likely to accept the chance to mate with him. After mating they will quickly get away from each other. If the male lingers the female may bite him. The male has better things to do though such as finding his next female to try to mate with.
The role of the female that has mated is to carefully calculate where she can place a nest for her eggs. She needs a location where predators are going to have a hard time getting to it. She also needs a location where the eggs have a chance of staying warm enough. The female won’t stick around to find out if the eggs survive or if her young hatch though. She will be long gone and those young will come out of the shells with instinct to guide them. They will know how to eat and how to find shelter on their own.
Predators
Humans have brought some issues to the lifestyle of the Galapagos Marine Iguana. For the most part they don’t have any natural predators. The spikes on them make it hard for predators to get them. However, many domestic dogs and cats have killed a high number of them. As more people move into these areas and invade the habitat it is going to continue to happen more frequently.
Hunting is a very common sport, and many people find that the Galapagos Marine Iguana is the ideal target. It is definitely something new and exciting to hunt in the eyes of plenty of people. They want to have stories to tell about something original.
Water related incidents are a problem too. Humans tend to leave debris and trash on the beach that can be a danger to the Galapagos Marine Iguana. Issues in the water including plastic, pollution, fishing nets, and boats can all cause serious harm or death for these Lizards. Yet at this time it isn’t deemed a large enough problem to be depleting the healthy population of them.
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