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Description
Torso shot of Baru from my Toledo Zoo visit this week. Really helps to show off the bulging muscles behind the skull that empower the immense biteforce of the crocodile. Taken at the Toledo Zoo in Toledo, Ohio on April 22nd, 2019.

Saltwater Crocodile
(Crocodylus porosus)

Range: Australia, Bangladesh, Brunei, Myanmar, Timor, India, Indonesia, Malaysia, Palau, Papua New Guinea, (including island chains,) Philippines, Sri Lanka and the Solomon Islands. Have been spotted as far north as the frigid Sea of Japan thousands of miles from their general range, along with being historically reported on Iwo Jima, Fiji, and New Caledonia along with as far west as the Seychelles Islands historically. Toledo Zoo sign information and some from Wikipedia.

Range Information from Dr. Adam Britton's website Crocodilian.com: Australia, Bangladesh, Brunei, Myanmar (Burma), Cambodia, China, India (including Andaman Islands), Indonesia, Malaysia, Palau (Caroline Islands) , Papua New Guinea, Philippines, Singapore, Sri Lanka, Solomon Islands, Thailand, Vanuatu (Banks Islands), Vietnam. Single individuals can be found some distance from their usual range (e.g. Japan, islands in the Indian Ocean), as they can travel long distances (over a thousand km) by sea - barnacles have been found on the scales of a few stray individuals. This sea-faring ability probably helps to explain their wide distribution. Historically present on the Seychelles islands (now extinct).

Size: Saltwater Crocodiles are the largest living reptile species, along with the heaviest. Large adult males can weigh up to 2,200-4,400 pounds in specimens up to 23 feet in length. Smaller adults up to 15 feet in length weigh been 900 and 1,100 pounds. Largest confirmed specimen was measured at 20.7 feet, accounting for partial tail loss, but the Guinness Book of World Records has a 23 foot male from Bhitarkanika Park in Odisha India listed as the world's largest living crocodile, and zoologists have also spotted several other 20 footers in that same area. Females grow much smaller, with lengths averaging 8-10 feet. Of all the crocodilian species, the Saltwater Crocodile shows the greatest sexual dimorphism, with the females being much smaller than the males, up to 50%.

Habitat: As its name implies, this species has a high tolerance for salinity, being found in brackish water around coastal areas and in rivers. However, it is also present in freshwater rivers, billabongs and swamps. Movement between different habitats occurs between the dry and wet season, and as a result of social status - juveniles are raised in freshwater areas, but eventually sub-adult crocodiles are usually forced out of these areas (used for breeding by dominant, territorial adults), into more marginal and saline areas. Subordinate animals unable to establish a territory in a tidal river system are either killed or forced out into the sea where they move around the coast in search of another river system. In recent years in northern Australia, saltwater crocodile populations in some areas have recovered to such an extent that increasing numbers are being forced further upstream into marginal habitat.
* Estuaries, freshwater rivers, billabongs, and swamps.

*Brackish water around coastal areas and in rivers.

*Saltwater crocodiles move to different habitats determined by the wet and dry season and their social status.

*They must return to a freshwater habitat to survive.

DIET: Saltwater crocodiles take a wide variety of prey, although juveniles are restricted to smaller items such as insects, amphibians, crustaceans, small reptiles and fish. The larger the animal grows, the greater the variety of items that it includes in the diet, although relatively small prey still make up the majority of the diet even in large adults. Prey items include crustaceans (e.g. mudcrabs) and vertebrates (e.g. turtles, goannas/lizards, snakes, shore and wading birds). Large adults occasionally take much larger prey include buffalo and domestic livestock, wallabies, wild boar, monkeys etc.

Even other mammalian predators have become prey items for this species, these would include sun bear, leopard, and even tiger. The largest prey items that are considered conventionally as the largest prey taken by male crocodiles are Asian water buffalo and gaur, the largest exant bovine with large bulls weighing up to 3,300 pounds. As a whole, saltwater crocodiles are extremely powerful animals; in one case, a one-tonne Suffolk stallion known to hall over two tonnes was pulled into water to its demise by a large male salt water crocodile, this was recorded in Gerald Wood's 1983 book The Guinness Book of Animal Facts and Feats.

Toledo Zoo sign information:

Food in the wild: Juveniles eat smaller prey such as insects, amphibians, crustaceans, small reptiles and fish. Adults eat what juveniles eat, along with bigger prey such as larger reptiles and wading birds. Large adults occasionally take large mammals, including buffalo and domestic livestock.

Food at the Zoo: Rabbits, rats, chicken, and fish, as well as smaller items for enrichment. Baru has shown a preference for beef over everything else so far from what I have heard from the keepers, but he should hopefully eat other things like chicken and rats.

BREEDING:
Breeding territories are usually established along tidal rivers, creeks and freshwater areas. Females reach sexual maturity at lengths of 2.2 to 2.5 m (10 to 12 years old). Males mature later (3.2 m, at around 16 years old). Females on average lay 40 to 60 eggs (this can range from 25 to 90) in mound nests made from vegetation (usually grasses and vines) and mud. These are normally constructed between the months of November and March during the wet season, but this varies slightly geographically. The mound helps to insulate the eggs from temperature extremes, hides them from predators, stops them from dehydrating, and also serves to raise the eggs above the ground to minimise the risk of flooding. Many nests are still flooded every year, however, killing all the unhatched embryos - in saltwater crocodiles flooding is the main cause of embryo mortality, not destruction by predators. If the nest is in danger of getting too dry, the female has apparently been observed to splash water onto it from a purpose-dug, adjacent pool, although the veracity of this observation is unknown. Although the female stays near the nest, eggs do occasionally fall foul of predators (e.g. monitor lizards, feral wild pigs in Australia) and human egg collectors. Juveniles normally hatch after 80 to 90 days but this varies with temperature (80 days at a sustained 32 celsius, longer if cooler). The female digs the hatchlings out of the nest when they start their characteristic chirping sounds, assisting some of them to the water by picking them up carefully and carrying them within the mouth. A lot of research has been carried out into TSD (Temperature-dependant Sex Determination) in this species, which is of value for captive breeding programs to influence the sex ratio, and to produce faster growing males for farming purposes. The highest percentage of males are produced around 31.6°C, with more females a few degrees above and below this. It is estimated that less than 1% of hatchlings will survive to reach maturity, due to flooding, predation (e.g. turtles, goannas, C. johnstoni), competition for resources, and social pressures (territorial males will kill and eat juveniles - they are one of the limiting factors in population growth along with competition).

Bite

Salties have the strongest bite of any animal today; and a large specimen can crush a full-grown bovid's skull between its jaws. A 5.2 m (17 ft)-long saltwater crocodile has been confirmed as having the highest bite force ever recorded for an animal in a laboratory setting, with a bite force value of 3,700 lbf (16,000 N) (surpassing the previous record of 2,125 lbf (9,450 N) made by a 3.9 m (13 ft)-long American alligator).[39][40] Taking the measurements of several 5.2 m (17 ft) crocodiles as reference, the bite forces of 6 m (20 ft) individuals were estimated at 7,700 lbf (34,000 N).[37] The study, led by Dr. Gregory M. Erickson, also shed light to the larger, extinct species of crocodilians. Since crocodile anatomy has changed only slightly for the last 80 million years, current data on modern crocodilians can be used to estimate the bite force of extinct species. An 11–12 m (36–39 ft) long Deinosuchus would apply a force of 23,100 lbf (103,000 N), twice that of the latest, higher bite force estimations of Tyrannosaurus rex.[37] The extraordinary bite of crocodilians is a result of their anatomy. The space for the jaw muscle in the skull is very large, which is easily visible from the outside as a bulge at each side. The nature of the muscle is so stiff, it is almost as hard as bone to touch, as if it were the continuum of the skull. Another trait is that most of the muscle in a crocodile's jaw is arranged for clamping down. Despite the strong muscles to close the jaw, crocodiles have extremely small and weak muscles to open the jaw. The jaws of a crocodile can be securely shut with several layers of duct tape.

Sources/Links

crocodilian.com/cnhc/csp_cpor.…
en.wikipedia.org/wiki/Saltwate…

Description
Torso shot of Baru from my Toledo Zoo visit this week. Really helps to show off the bulging muscles behind the skull that empower the immense biteforce of the crocodile. Taken at the Toledo Zoo in Toledo, Ohio on April 22nd, 2019.

Saltwater Crocodile
(Crocodylus porosus)

Range: Australia, Bangladesh, Brunei, Myanmar, Timor, India, Indonesia, Malaysia, Palau, Papua New Guinea, (including island chains,) Philippines, Sri Lanka and the Solomon Islands. Have been spotted as far north as the frigid Sea of Japan thousands of miles from their general range, along with being historically reported on Iwo Jima, Fiji, and New Caledonia along with as far west as the Seychelles Islands historically. Toledo Zoo sign information and some from Wikipedia.

Range Information from Dr. Adam Britton's website Crocodilian.com: Australia, Bangladesh, Brunei, Myanmar (Burma), Cambodia, China, India (including Andaman Islands), Indonesia, Malaysia, Palau (Caroline Islands) , Papua New Guinea, Philippines, Singapore, Sri Lanka, Solomon Islands, Thailand, Vanuatu (Banks Islands), Vietnam. Single individuals can be found some distance from their usual range (e.g. Japan, islands in the Indian Ocean), as they can travel long distances (over a thousand km) by sea - barnacles have been found on the scales of a few stray individuals. This sea-faring ability probably helps to explain their wide distribution. Historically present on the Seychelles islands (now extinct).

Size: Saltwater Crocodiles are the largest living reptile species, along with the heaviest. Large adult males can weigh up to 2,200-4,400 pounds in specimens up to 23 feet in length. Smaller adults up to 15 feet in length weigh been 900 and 1,100 pounds. Largest confirmed specimen was measured at 20.7 feet, accounting for partial tail loss, but the Guinness Book of World Records has a 23 foot male from Bhitarkanika Park in Odisha India listed as the world's largest living crocodile, and zoologists have also spotted several other 20 footers in that same area. Females grow much smaller, with lengths averaging 8-10 feet. Of all the crocodilian species, the Saltwater Crocodile shows the greatest sexual dimorphism, with the females being much smaller than the males, up to 50%.

Habitat: As its name implies, this species has a high tolerance for salinity, being found in brackish water around coastal areas and in rivers. However, it is also present in freshwater rivers, billabongs and swamps. Movement between different habitats occurs between the dry and wet season, and as a result of social status - juveniles are raised in freshwater areas, but eventually sub-adult crocodiles are usually forced out of these areas (used for breeding by dominant, territorial adults), into more marginal and saline areas. Subordinate animals unable to establish a territory in a tidal river system are either killed or forced out into the sea where they move around the coast in search of another river system. In recent years in northern Australia, saltwater crocodile populations in some areas have recovered to such an extent that increasing numbers are being forced further upstream into marginal habitat.
* Estuaries, freshwater rivers, billabongs, and swamps.

*Brackish water around coastal areas and in rivers.

*Saltwater crocodiles move to different habitats determined by the wet and dry season and their social status.

*They must return to a freshwater habitat to survive.

DIET: Saltwater crocodiles take a wide variety of prey, although juveniles are restricted to smaller items such as insects, amphibians, crustaceans, small reptiles and fish. The larger the animal grows, the greater the variety of items that it includes in the diet, although relatively small prey still make up the majority of the diet even in large adults. Prey items include crustaceans (e.g. mudcrabs) and vertebrates (e.g. turtles, goannas/lizards, snakes, shore and wading birds). Large adults occasionally take much larger prey include buffalo and domestic livestock, wallabies, wild boar, monkeys etc.

Even other mammalian predators have become prey items for this species, these would include sun bear, leopard, and even tiger. The largest prey items that are considered conventionally as the largest prey taken by male crocodiles are Asian water buffalo and gaur, the largest exant bovine with large bulls weighing up to 3,300 pounds. As a whole, saltwater crocodiles are extremely powerful animals; in one case, a one-tonne Suffolk stallion known to hall over two tonnes was pulled into water to its demise by a large male salt water crocodile, this was recorded in Gerald Wood's 1983 book The Guinness Book of Animal Facts and Feats.

Toledo Zoo sign information:

Food in the wild: Juveniles eat smaller prey such as insects, amphibians, crustaceans, small reptiles and fish. Adults eat what juveniles eat, along with bigger prey such as larger reptiles and wading birds. Large adults occasionally take large mammals, including buffalo and domestic livestock.

Food at the Zoo: Rabbits, rats, chicken, and fish, as well as smaller items for enrichment. Baru has shown a preference for beef over everything else so far from what I have heard from the keepers, but he should hopefully eat other things like chicken and rats.

BREEDING:
Breeding territories are usually established along tidal rivers, creeks and freshwater areas. Females reach sexual maturity at lengths of 2.2 to 2.5 m (10 to 12 years old). Males mature later (3.2 m, at around 16 years old). Females on average lay 40 to 60 eggs (this can range from 25 to 90) in mound nests made from vegetation (usually grasses and vines) and mud. These are normally constructed between the months of November and March during the wet season, but this varies slightly geographically. The mound helps to insulate the eggs from temperature extremes, hides them from predators, stops them from dehydrating, and also serves to raise the eggs above the ground to minimise the risk of flooding. Many nests are still flooded every year, however, killing all the unhatched embryos - in saltwater crocodiles flooding is the main cause of embryo mortality, not destruction by predators. If the nest is in danger of getting too dry, the female has apparently been observed to splash water onto it from a purpose-dug, adjacent pool, although the veracity of this observation is unknown. Although the female stays near the nest, eggs do occasionally fall foul of predators (e.g. monitor lizards, feral wild pigs in Australia) and human egg collectors. Juveniles normally hatch after 80 to 90 days but this varies with temperature (80 days at a sustained 32 celsius, longer if cooler). The female digs the hatchlings out of the nest when they start their characteristic chirping sounds, assisting some of them to the water by picking them up carefully and carrying them within the mouth. A lot of research has been carried out into TSD (Temperature-dependant Sex Determination) in this species, which is of value for captive breeding programs to influence the sex ratio, and to produce faster growing males for farming purposes. The highest percentage of males are produced around 31.6°C, with more females a few degrees above and below this. It is estimated that less than 1% of hatchlings will survive to reach maturity, due to flooding, predation (e.g. turtles, goannas, C. johnstoni), competition for resources, and social pressures (territorial males will kill and eat juveniles - they are one of the limiting factors in population growth along with competition).

Bite

Salties have the strongest bite of any animal today; and a large specimen can crush a full-grown bovid's skull between its jaws. A 5.2 m (17 ft)-long saltwater crocodile has been confirmed as having the highest bite force ever recorded for an animal in a laboratory setting, with a bite force value of 3,700 lbf (16,000 N) (surpassing the previous record of 2,125 lbf (9,450 N) made by a 3.9 m (13 ft)-long American alligator).[39][40] Taking the measurements of several 5.2 m (17 ft) crocodiles as reference, the bite forces of 6 m (20 ft) individuals were estimated at 7,700 lbf (34,000 N).[37] The study, led by Dr. Gregory M. Erickson, also shed light to the larger, extinct species of crocodilians. Since crocodile anatomy has changed only slightly for the last 80 million years, current data on modern crocodilians can be used to estimate the bite force of extinct species. An 11–12 m (36–39 ft) long Deinosuchus would apply a force of 23,100 lbf (103,000 N), twice that of the latest, higher bite force estimations of Tyrannosaurus rex.[37] The extraordinary bite of crocodilians is a result of their anatomy. The space for the jaw muscle in the skull is very large, which is easily visible from the outside as a bulge at each side. The nature of the muscle is so stiff, it is almost as hard as bone to touch, as if it were the continuum of the skull. Another trait is that most of the muscle in a crocodile's jaw is arranged for clamping down. Despite the strong muscles to close the jaw, crocodiles have extremely small and weak muscles to open the jaw. The jaws of a crocodile can be securely shut with several layers of duct tape.

Sources/Links

crocodilian.com/cnhc/csp_cpor.…
en.wikipedia.org/wiki/Saltwate…