Brachina Gorge in the Flinders Rangers in South Australia is absolutely stunning and, I think, a quintessentially Australian landscape. In the middle of the gorge, old worn down quartzite hills tower into the sky, rich in earthy oranges, yellows and creamy whites. The hills are speckled with sparse green-grey vegetation. In the bottom of the gorge are massive ancient river red gums that rise up from the creek bed which is filled with rounded river pebbles and gravels in a variety of greys, reds, purples and almost blues. Each stone has white marks from being plonked into each other in the infrequent deluges that cause the creek to fill with water.
We were driving through Brachina Gorge as a scenic route for our journey heading further north. As the car suspension was bounding up and down over the pebbles we came to a section of creek with small puddles of water. The water was encouraging plant growth in the river bed which was in turn attracting an iconic resident of Brachina Gorge, the Yellow-footed Rock-wallaby. After enjoying watching these wonderful animals for some time, something caught our attention making its way through the plants and sticks near the edge of the creek. Boldly strolling along was an echidna, occasionally poking its long snout into crevices and holes. It is unusual to see native Australia mammals so unfazed by the presence of humans, but when you are covered in an armament of spines you can be pretty confident that not too many creatures will mess with you. The spines had a light base and tapered to their points that were sometimes dark coloured. From underneath the spines poked a face with puny dark eyes and a long moist snout. Propelling the spiny beast along were a set of robust legs with strong claws and feet.
Echidnas are an iconic Australian animal and draw attention for a several reasons. They are one of only two kinds of egg laying mammals, along with platypus. They use their strong forelimbs to dig into hard ground, ant or termite nests, and use their sticky long tongue to slurp up ants, termites and other insects from the crevices and holes. During winter echidnas go into torpor, a period where the animal becomes inactive and lowers its metabolic rate and body temperature. When active and regulating its body temperature echidnas are at about 32°C, but when in torpor the body temperature declines to close to that of the surrounding soil temperature that they maybe buried in. So in cold areas this may mean a body temperature as low as 4°C. During these periods of torpor echidnas may only breath once every three minutes.
Echidnas also provide an example of convergent evolution where two unrelated species of animals evolve similar characteristics due to similar selective pressures from their environment. Both echidnas and hedgehogs have the same defensive strategy, being covered in spines, but are unrelated to each other. Echidnas are monotremes, whereas hedgehogs are eutherian mammals that give live birth rather than have eggs like monotremes.
Echidnas are found throughout Australia, and during summer can be found foraging in the bush during the day or night. They are fascinating animals to watch, and you are more likely to get a good view of these interesting animals than many other Australian mammals. So if you are in the Australian bush keep an eye out for these wonderful and curious creatures.