Animals

Facts about Gila monster

25 Gila monster facts

Heloderma suspectum

The Gila monster is one of the few venomous lizards in the world, the only extant venomous species in the United States. It is easily distinguished by its yellow, orange, or pink pattern on black skin. Most commonly found in the Sonoran, the Mojave, and the Chihuahuan deserts, their numbers decline yearly.

Gila monster
1
It is native to the American Southwest and the Sonora state of Mexico.
2
It is the largest lizard in the U.S. still in existence.
Their length ranges from 26 to 36 centimeters SVL (snout-vent length), and with a tail, they can reach up to 56 centimeters in length.
3
The genus Heloderma dates back to the Miocene (23,3—5,333 mya).
4
It is the only venomous lizard in the U.S.
5
It is closely related to four species of beaded lizards–one from Guatemala (Heloderma charlesbogerti), and three from Mexico (Heloderma alvarezi, Heloderma horridum, and Heloderma exasperatum).
6
Its skin is black, with a pink, orange, or yellow pattern.
7
Its name derives from the Gila River basin in Arizona.
It was where they were first discovered in the 1800s.
8
The Gila monster has an excellent sense of smell.
It uses it primarily to hunt for prey. It picks up the scent with its tongue, transferring it to the Jacobson organ—an olfactory organ located in the nasal cavity in many tetrapods.
9
It primarily feeds on eggs of birds, reptiles, and small mammals.
The egg does not need to be crushed, it can be eaten whole. The Gila monster is capable of climbing trees, cacti, and walls, in order to get to the nest.
10
It will also feed on small organisms, such as hares, mice, squirrels, birds, frogs, lizards, or snakes.
Depending on the size of the prey, it can be crushed first, or eaten alive, starting with the head.
11
While the adult Gila monster eats approximately one-third of its body weight per one meal, the young eats around 50% of its body weight per one meal.
12
The Gila monster can store fat in their tails, so typically three to four meals will suffice for the whole season.
13
Gila monsters fell prey to coyotes, badgers, snakes, and birds of prey.
14
The average lifespan of the Gila monster is 20 years in the wild.
In captivity, they can exceed 35 years.
15
Unlike snakes, the Gila monster produces its venom in salivary glands at the end of its lower jaws.
It has to bite its prey to release the toxin into the open wound.
16
Although its bite is painful, there are no reported deaths of humans.
17
Scientists believe that since it preys on small animals and eggs, it evolved to use the venom solely to scare away predators.
18
The Gila monster spends approximately 95% time buried in underground burrows.
It would emerge for feeding and sunbaths.
19
Gila monsters reach sexual maturity at 4 to 5 years old.
20
The mating season lasts from April to May.
21
The female Gila monster lays up to 13 eggs in a single clutch.
The average is five to six, however. The young hatch after four to five months of incubation.
22
The young typically enter the brumation after hatching.
The average size of a hatchling is 15 centimeters long. It is fully independent, which includes the ability to use its venom straight away.
23
Gila monsters are solitary.
Their territory covers an area of 1,6 square kilometers. They gather only for mating purposes.
24
It is diurnal, with most activity taking place in the morning.
25
Although it is listed as a near-threatened species, it is protected by state laws in the U.S.
Mostly, it is prohibited to collect them from the wild, and in some states, it is illegal to possess one as a pet. In New Mexico, it is listed as Endangered and under full protection.
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