Crocodiles are extraordinary creatures, having survived since the age of dinosaurs with very few adaptations. Australia is home to only two species of crocodile, but can boast having the largest; the Saltwater Crocodile. Although ‘salties’ can live in the sea, they prefer estuaries and freshwater swamps across northern Australia and will often venture inland during the breeding season. The Saltwater Crocodile lays clutches of 30-70 eggs with the sex of the hatchlings dependent on the temperature at which the eggs are incubated. Kakadu & Arnhem Land offers numerous boating opportunities to view Australia’s apex predator.
The Freshwater Crocodile (also known as Johnstone’s Crocodile) lives in rivers, swamps and billabongs also in northern Australia, but is much smaller and generally harmless to humans. They typically lay their eggs around June in the dry season and can be seen congregating in large numbers around waterholes and billabongs. Once hatched, females protect their young from predators such as turtles, raptors, pythons, sea eagles and even large fish.
Autumn: Mar-May, Kakadu & Arnhem Land
The renowned Frilled-neck Lizard is more active during the wet season, but can still be seen at this time with it’s spectacular frill that encircles its neck when alarmed. Males are larger than females and can reach up to a metre in length. Mertens’ Water Goannas have their young at this time and are a common sight along the billabongs and streams, where they forage for extended periods underwater, feeding on fishes, frogs and crustaceans. Sand and Yellow-spotted Goannas are found further inland across the Savanna woodlands, searching for reptile and bird eggs, invertebrates, lizards and birds.
The beautiful Dahl’s Aquatic Frog is commonly seen on the floodplains at the end of the wet season where they float during the day and bask on lily pads. They are typically green with a beautiful emerald stripe down the middle of the back and are common prey for the Merten’s Water Goanna. The Northern Dwarf Tree Frog, Little Green Tree Frog and Brown Tree Frog are also common sightings across the region.
Green Tree Snakes, Children Pythons, Banded Tree Snakes and Olive Pythons are more active along the billabongs and floodplains during this time, commonly sighted from the airboats, as are the regions most famous resident, the Saltwater Crocodile.
Winter: Jun-Aug, Kakadu & Arnhem Land
As waters begin to recede, Saltwater Crocodiles can be spotted in greater volumes, with small mammals and birds falling victim to ambush attacks along the waters edge, along with region’s most famous fish, the Barramundi. Freshwater Crocodiles are typically found further up the escarpments with females laying a clutch of 4-20 eggs in the sand in August. Unlike Saltwater Crocodiles the females do not guard the nest, however, they will return and excavate the nest when the eggs have hatched around November.
Green Tree Snakes, Children Pythons, Banded Tree Snakes and Olive Pythons are active along the billabongs and floodplains until the end of June, when they become more lackadaisical due to increased heat and dry conditions. One of the most intriguing smaller lizards seen at this time is the Rough Knob-tailed Gecko, with their beautiful rich purple coloured eyes and spiny rosettas across their body a remarkable sight. The Desert Tree Frog, Rocket Frog, Tornier’s Frog, Roth’s Tree Frog, Northern Dwarf Tree Frog and Little Green Tree Frog are some of the more common of the 26 frog species found across the region.
Spring: Sep-Nov, Kakadu & Arnhem Land
The largest of all living reptiles is the Saltwater Crocodiles. They are most active at this time due to males and females engaging in courtship. Females will lays eggs between November and March in a nest mound made up of mud and vegetation, typically laying from 30 to 70 eggs. The dry season is the best time to see these prehistoric creatures as their numbers concentrate in shrinking pockets of water.
Freshwater Crocodiles feed on many small animals including fish, frogs, lizards, snakes, rats, bats and birds. ’Freshies’ prefer to stay clear of their Saltwater cousins at this time and inhabit areas above the escarpment in Kakadu.
There are numerous lizards active including the alluring Fire-tailed Skink, with its bright-red tail a beautiful site against the ochre coloured rocks. Sand and Yellow-spotted Goannas, can be seen stalking through the woodlands, with some laying their eggs into the cathedral termite mounds to protect their eggs from the high temperatures. The Copland’s Rock Frog inhabits the rock escarpments and is particularly active along the edges of creeks, with breeding commencing in October.