Is there a difference in personality in male vs. female? Generally speaking, no. Their personality is as individual as humans. Some are more tolerant of people and other animals. Females will have a tendency to become more aggressive to male cage mates and people right after a mating period.
In a correspondence with Honolulu zooDo they act differently when in a group vs. single housing? Yes. In many instances, they just don't get along with one another and separation is needed. A "howdy" period of introduction is important for housing or introducing one animal to another or to a group, since this species is solitary in nature. Many display defensive or territorial behaviors toward their cage mates or keepers. In groups, the individual animals will tend to be more flighty and less easily handled. Single-housed animals are more accepting of human interaction and tend to be less aggressive. Here is an example of how changes can occur: email from zoo keeper.
"As for our females the wild caught ones were very aggressive to the keepers and to the male until he got to be around 7 feet long. We got the wild caught females where we could handle them, but with caution. The female we currently have is captive hatch and she has the temperament of a puppy."
Can they be tamed? "Taming" is a poor choice of words because it implies domestication. This species, like most wild animals, cannot be domesticated in any way. They do, however, have the ability to become more desensitized to handling when raised from hatchlings. Here is an example: Croc and patrons. They are very smart and do have the ability to learn.
How smart are they? Many believe they are the smartest of the monitor species. They have the intelligence of dogs in some ways, but can have the stubbornness of cats as well. They can be trained and are considered to have reasoning abilities.
Are they aggressive? Yes, they can be. They may behave aggressively toward other monitors in their enclosure. Ovulating females are especially aggressive towards males. They are also very flighty animals and can become agitated very quickly, resulting in aggression, and may bite if provoked.
In a correspondence with Honolulu zoo
"...when he became a successful breeder his behavior changed again. He started to be confident but cautious to the keepers and we then thought we needed to train him. He is now 9 feet long total length and one of the smartest reptiles we have. We trained him with various food items and now he can come when we call his name. He will also present his leg for when we put him in the catch pole to take him outside of his enclosure for enrichment. Once we get him on the pole he waits for us to command him to come out and then his enrichment begins. He will look back at us and wait for us to throw his food item. After the item lands on the walkway we tell him to fetch and then he goes to get his food item. After he eats it he looks back for the next one and does the whole thing again and again until all of his food items are gone. When done we command him home and we turn him around and then he heads back to his enclosure."
What do they use that tail for? This arboreal (tree-dwelling) species uses its tail, which is somewhat prehensile, for balance and to curl around branches when crawling through trees. The tail has also been used as a whip for self-defense with reports of keepers hit in the eye, although whether they actually aim for the eye is only speculation.
In a correspondence with Honolulu zoo
"Our male Crocodile monitor was very shy when he was younger. Over the years he changed a lot. When we received him he was shy and very intimidated by the female and keepers. After a few years and size about 7 feet he became very aggressive to the keepers. Using his tail as a weapon he broke my eye glasses and cut my eye."
Do they bite? Yes, they can. The crocodile monitor has the longest teeth of any monitor and powerful jaw pressure. Bites from these animals can rip flesh from fingers, tear muscle tissue, cause major bruising, and sever veins and arteries. The use of thick welding gloves do not provide enough protection against their protruding teeth. A high respect and good judgement should be exercised towards these lizards.
Owner reports: " I wasn't use to the long tail and accidentally stepped on hers several times, she gave me a reminder...".
anonymous submission..."...grabbed and knelt too far forwards while vet wanted to take a blood sample."
Both of these are admittedly, the owners fault and do not blame the animal for their mistake.
Is their bite poisonous or venomous? No. They do have bacteria in their mouth which can cause an infection if you are bitten. Immediate medical attention and the use antibiotics are the recommended treatment. To our knowledge, they are not like their cousin the Komodo dragon.
Do they make good pets? "Pet" is a poor word choice because it implies domestication like a common dog. They are not that kind of animal. These are considered to be an advanced reptile for experienced persons and not good for someone just starting into the reptile hobby. They are very expensive to buy, house, and feed as adults. Some zoos and even experienced keepers have difficulty keeping these animals as they can be very destructive on their habitats and can cause serious injury to an unprepared keeper. Handling them can be very stressful to the animal so holding should be kept minimal.
