Yes, crocodiles lay eggs. They lay eggs in the ground, which is commonly called a crocodile nest. All species of crocodiles lay eggs. Some lay eggs in holes, and some build a mound.
Crocodiles lay a lot of eggs, but not all of them survive. In the wild, there are crocodile egg predators, like the raccoon. The eggs that survive hatch and the temperature of the nest is what determines the sex of the crocodile hatchlings.
Do Crocodiles Give Live Birth?
Crocodiles lay eggs, and no species give live birth. However, a recent discovery of an ancient fossil suggests that the crocodile’s ancestor may have given birth to live young.
Laying eggs is one of the defining characteristics of reptiles like crocodiles.
One must note that not all reptiles lay eggs. Some snakes, which are reptiles, give live birth. A recent discovery shows that a group of animals where the crocodile belongs, the Archosauromorpha, gave live birth.
This species is the Dinocephalosaurus orientalis. The fossil was “pregnant.” There was an embryo in the fossil in its abdominal region. This discovery proves that not all reptiles laid eggs, and even the ancestor of the modern crocodile gave birth.
How Many Eggs Does a Crocodile Lay?
Different crocodile species lay different numbers of eggs. A group of eggs is called a clutch, and the average is 30 to 60 eggs per laying. Some crocodiles lay only seven eggs, and some species that lay up to 95 eggs at a time.
The nesting period can last between a few weeks to six months. Some females are observed to build trial nests, thinking they are pregnant. However, they abandon these nests if the fertilization is incomplete.
The egg-laying process takes place usually at night, and it can last up to 40 minutes. Females are protective of their nests and also their young.
Do Crocodiles Lay Eggs in Water?
Crocodiles do not lay eggs in water because they are not amphibians. However, they lay eggs close to bodies of water.
Sometimes, some crocodile species dig wallows that eventually fill with water. They stay in these wallows while the eggs in the nest beside them are dry.
When crocodiles lay eggs, they cannot transport the eggs to another location so the eggs must be in a perfect spot with the right temperature and safe from predators.
Read More: How Fast are Crocodiles?
Although crocodiles are great swimmers, they are not amphibians and they lay their eggs on land
How Do Crocodiles Choose a Nest Site?
Crocodiles choose a nesting site based on ground temperature and moisture. The successful incubation and survival of the eggs depends on finding a nesting spot with the perfect temperature and moisture.
As such, the site choice and the nest-building behavior of a crocodile depends on the incubation temperature. Large nests that are under a sunny environment are warmer. They are better than shaded nests.
Crocodiles can modify the size of the nest and its exposure to ensure that the eggs survive and hatch. Crocodiles do not randomly build nests in the ground. Since they know the temperature, they may choose to abandon the nest if it is not suitable.
Read More: Do Crocodiles Hibernate?
If the conditions are not right, some may not lay eggs at all. If the crocodile lives in a hot area, they are forced to lay eggs in the ground that is exposed to the sun. They make test holes, and they also choose sites that are less rocky.
Crocodiles need water to help regulate the thermal conditions of the soil. Both temperature and moisture are required for a successful incubation.
Crocodiles have the ability to modify their environment if the conditions are extreme, which is how they have survived for millions of years.
What Happens During Crocodile Egg Incubation?
Eggs have an incubation of about 80 days, but some are shorter. Some crocodile farms have experts who take the eggs from the nest and then incubate the eggs in a laboratory. It is safer this way, and it guarantees a higher survival rate.
The temperature has an influence on the rate of development of the eggs. Warmer conditions make the embryos grow faster. After two to three weeks, the embryos will now have a sex.
Crocodile eggs do not have sex chromosomes. Instead, the sex of a crocodile is determined by the temperature of the egg during the incubation period.
At 86°F (30°C) or below, it is likely that the hatchlings will be females. At 91°F (33°C) or above, it’s likely that the hatchlings will be males.
For some species, the temperature scales are reversed, with higher temperatures yielding female hatchlings.
Crocodiles that develop in the egg have an egg tooth. They use this to crack the eggshell, and then they poke their nose out. Unlike turtles, baby crocodiles cannot dig their way out of the nest. The mother crocodile has to dig them out.
The mother also helps out baby crocs that have difficulties coming out of their shell. The mother squeezes them gently out of the egg. If the eggs are dead, the mother eats them. The mother then carries the baby crocs to the water.
FAQs:
Do Crocodile Eggs have Shells?
Crocodile eggs have hard, calcified outer shells, similar to a chicken egg. Inside the hard shell is a second shell that’s soft and leathery.
How Often do Crocodiles Lay Eggs?
Crocodiles lay eggs once a year. Some crocodiles lay eggs every two years. It all depends upon the health of the crocodile and the environmental conditions.
Summary
Crocodiles build nests and lay eggs. Some are hole nests, and some are mound nests.
Crocodiles do not lay eggs in the water, as they are not amphibians. The temperature affects how fast the embryo grows, and what the sex is going to be.
Stuart is the editor of Fauna Facts. He edits our writers’ work as well as contributing his own content. Stuart is passionate about sustainable farming and animal welfare and has written extensively on cows and geese for the site.