Welcome to Croctober 2023! Get ready to embark on a thrilling journey into the world of one of nature’s most formidable and fascinating creatures: the crocodile (and other crocodilians). Throughout this month, we’ll be diving deep into the depths of these ancient reptiles, uncovering their secrets, and celebrating their remarkable existence.
Common Name: Nile Crocodile
Scientific Name: Crocodylus niloticus
Family: Crocodylidae – Crocodile Family
Locations: Angola, Botswana, Burund, Cameroon, Congo, The Democratic Republic of the Congo, Egypt, Equatorial Guinea, Eritrea, Eswatini, Ethiopia, Gabon, Kenya, Madagascar, Malawi, Mozambique, Namibia, Rwanda, Somalia, South Africa, South Sudan, Sudan, Tanzania, Uganda, Zambia, and Zimbabwe
Size: 16 – 20 feet (4.8 – 6 meters), 500 – 1,650 pounds (227 – 750 kilograms)
The Nile Crocodile lives not just by the Nile River but throughout most of Africa. The croc can live in salt water but prefers fresh or brackish waters. The males of the species are larger than the females, typical for crocodilians. They are apex predators. They are also considered the second largest living reptile by body mass.
During the mating season, the male crocodiles try to attract the females by bellowing, blowing air out of their nose, or smacking their snout on the water. Honestly, pretty much anything to get the females attention. Males can fight between themselves over territory. I won’t go into the details on the mating but its not great for the female.
One to two months later, the female lays between 25 – 80 eggs in a nest that she made. She needs no man.
The International Union for the Conservation of Nature (IUCN) Red List assesses the Nile Crocodile as Least Concern for Extinction. The crocodile has a wide range and are numerous throughout it.
Common Name: Black Caiman
Scientific Name: Melanosuchus niger
Family: Alligatoridae – Alligator family
Locations: Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, and Peru
Size: 7.25 – 14.1 feet (2.2 to 4.3 meters) , can grow to 16.5 feet (5 meters)
The Black Caiman is the largest living species of caiman, capable of reaching 16.5 feet long and reaching over a thousand pounds! They live in the Amazon River Basin, where they are one of the apex predators there. Once the Black Caiman reaches full size, only humans attempt to hunt them. The caiman feeds on a variety of animals such as snakes, fish, monkeys, frogs, and even other caiman. They hunt at night, where their excellent night vision help out.
At the end of the dry season, the females start to build their nests of soil and vegetation. Additionally, these nests are almost 5 feet (1.5 meters) long and 2 and a half feet (0.75 meters) wide. At the start of the wet season (May – June), the caiman lays between 30 – 60 eggs. The mother protects her nests from predators until they hatch. The eggs hatch between 42 – 90 days after being laid. The mother helps dig the hatchlings out of the nest. Then, the offspring stick close to their mom. Even with their mom’s protection, a large number of the offspring die.
Black Caiman Conservation
The International Union for the Conservation of Nature (IUCN) Red List categorizes the Black Caiman as Conservation Dependent. The IUCN Red List no longer uses this category. The caiman’s status hasn’t been reassessed since 2000 when they were placed there. Before, they were categorized as endangered due to over hunting of the species. Hunting of the species has slowed down thanks to legal protections.
Common Name: American Crocodile
Scientific Name: Crocodylus acutus
Family: Crocodylidae – Crocodile Family
Locations: Belize, Colombia, Costa Rica, Cuba, Dominican Republic, Ecuador, El Salvador, Guatemala, Haiti, Honduras, Jamaica, Mexico, Nicaragua, Panama, Peru, United States, Venezuela, and Bolivia
US Location: Florida
Average Male Size: 9.5 – 13.1 feet (2.9 – 4 meters)
Average Female Size: 8.2 – 9.8 feet (2.5 -3 meters)
Maximum Size: 20 feet (6.1 meters)
The American Crocodile has the most widespread range of any crocodile in the Americas. They reach from southern Florida, through Central America, and down to northern South America. They live in fresh or brackish water of estuaries, lagoons, and mangrove swamps.
The American Crocodile breeds during the dry season. The males are highly territorial and fight other males for the best land. The courtship and breeding takes place in the water. The male’s main advertisement to females is 1 to 3 headslaps. If this is acceptable for the female, then she either puts her head on his back / head or performs some snout lifts. Next, the male lets out a low frequency noise that makes water blow up off of his back, called water dancing. Finally, the two mate in the shallows.
The female builds their nests on elevated, well drained soil. The female lays between 30 – 60 eggs. Temperature determines the sex of the offspring. Temperatures between 88- 91° F (31.1 – 32.7° C) produce mostly male offspring. Meanwhile, temperatures lower than 88° F (31.1° C) result in mostly females. The female parent protect the nest from scavengers such as raccoons and iguanas. The eggs hatch in 75 – 80 days at the start of the wet season. The female helps dig ups the hatched babies and carries them to the water.
American Crocodile Conservation
The International Union for the Conservation of Nature (IUCN) Red List classifies the American Crocodile as Vulnerable to Extinction. The Croc’s populations has improved than it previously had been. It was listed as Endangered before conservation work was done to help save them. Unfortunately, they were over-hunted for their hides before being listed on the US Endangered Species List in the 1970s. However, they moved from listed as federally endangered to federally threatened. Protections are still in place to help conserve the species from overharvesting. Unfortunately, their habitat is under threat of destruction to make room for more urban areas.
Common Name: Gharial, Gavial, and Fish-eating Crocodile
Scientific Name: Gavialis gangeticus
Family: Gavialidae – Gharial family
Locations: Bangladesh, India, and Nepal
Female Size: 8.5 feet (2.6 meters) – 14.75 feet (4.5 meters)
Male Size: 10 feet (3 meters) – 20 feet (6 meters)
The Gharial is known for their long, narrow snout that is adept at catching fish. Males of the species develop a gross looking growths called a ghara on the tip of their snouts once they reach sexual maturity. Ghara means Mud Pot in Hindi. They use the ghara to vocalize more loudly and blow bubbles during their mating displays.
The mating season for the frogs happens during the dry season, between March and April. The males stake out their territory and defend it from rival males. Females in the territory mate with the male and she then lays an average on 40 eggs. Their eggs are the largest eggs of all the living crocodilians, averaging over 5 ounces. The male provides no parental care for their offspring and will move onto reproducing with other females. The female stays to protect her nest from predators. The eggs hatch between 30 – 80 days. After hatching, the mom still protects the babies for weeks and even months.
The International Union for the Conservation of Nature (IUCN) Red List classifies the Gharial as Critically Endangered. Their habitat has been drastically altered due to damming and diverting water from the rivers. Gharials don’t do well far away from the river. These alterations to the habitat causes them to have to travel farther on land when moving to new spots in their river, increasing their chance of dying. Overfishing is also rampant in rivers that the Gharial is found in. This reduces their food source and they get stuck or injured by nets.
Common Name: Saltwater Crocodile or Salties
Scientific Name: Crocodylus porosus
Family: Crocodylidae – Crocodile family
Locations: Australia, Bangladesh, Brunei, Cambodia, East Timor, India, Indonesia, Malaysia, Myanmar, Palau, Papua New Guinea, Philippines, Singapore, Solomon Islands, Sri Lanka, Thailand, Vanuatu, and Vietnam
Size: 17 – 23 feet (5.1 – 7 meters)
The Saltwater Crocodile is the largest living crocodile species in the world. These crocodiles can reach 23 feet and over 2,200 pounds! They received their name due to their resistance to saltwater. Most crocodiles only enter the saltwater in emergencies while the Saltwater Crocodile just lives there. They are capable of living over 70 years in the wild and longer in captivity.
Saltwater Crocodile Reproduction
The Saltwater Crocodile breeds during the wet season when the water levels are the highest. The females select a nesting site where she and a male eventually mates. The male is a dead beat dad and doesn’t provide any care for his offspring. He leaves the mom and tries to find more potential mates. The female crocodile shows a high amount of parental care.
The mother guards her nest of eggs, even splashing water on the eggs to help prevent them from drying up. The eggs take 3 months to hatch. The sex of the offspring depend on the incubation temperature. Temperatures below 86 ºF (30 ºC) result in females. Meanwhile, temperatures above 89 ºF (32 ºC) results in male offspring. Once the eggs hatch, the female digs out the babies and carries them to the water in her mouth. Then, she protects the babies until they are able to take care of themselves. What a mom!
The International Union for the Conservation of Nature (IUCN) Red List categorizes the Saltwater Crocodile as Least Concern for Extinction. They have a fairly large range but the destruction of potential nesting sites is a concern. Another threat is hunting of the crocs for their pelts and meat. These threats are rather low though.