For the past 40 years, thanks to the passion and enterprise of scientists and volunteers, many dinosaur fossils and footprints have been found in Bass Coast. Most of the polar dinosaur bones that have been found so far belong to small, fast-running plant eating dinosaurs, but there is also evidence of small and large theropod (meat-eating) dinosaurs, ankylosaurs and ceratopsian or horned dinosaurs. Were they unique to the area? (not found anywhere else) The dinosaurs found along the Bass Coast are similar to those found elsewhere in the world, but are different species or even genera. However, dinosaurs from polar regions are very rare in the fossil record and the Bass Coast dinosaurs were well adapted to an extreme environment that does not exist today.

The Bass Coast polar dinosaurs lived in this part of Victoria between 106 and 130 million years ago when Australia was situated at approximately 70°south; much further south than it is today. The area that is now the Bass Coast was the northern part of a giant rift valley that existed between the south coast of Australia and Antarctica, somewhat like the East African Rift Valley of today.

The dinosaur fauna was dominated by small ornithopod (plant-eating) dinosaurs approximately 1 to 1.5 metres long, but there is tantalizing evidence of much larger theropod (meat-eating) dinosaurs up to five metres long, also living in this area at the same time.

Since the first Australian dinosaur bone was discovered in 1903 at Eagles Nest, prospecting and excavations beginning in the late 1970s have led to the discovery of a number of different types of dinosaurs. The small herbivorous ornithopod dinosaurs such as Qantassaurus intrepidus and Galleonosaurus dorisae were the most common. The small horned dinosaur Serendipaceratops arthurcclarkei was also an herbivore, as was an unnamed species of ankylosaur, similar to Minmi paravertebra. There were also small and large carnivorous dinosaurs, but their fossil bones are rarely found. Koolasuchus cleelandi was a giant carnivorous amphibian that lived in the area alongside the dinosaurs, and probably enjoyed them for dinner!

There is no physical evidence that the Bass Coast dinosaurs migrated long distances. They could not have travelled too far north as the giant inland Eromanga Sea that covered most of Queensland, New South Wales and parts of South Australia would have been a barrier. It is more likely that they over-wintered or perhaps dug burrows in which to shelter against the cold.

Approximately 130 million years ago, Australia was still attached to Antarctica along the south coast and formed the last remnant of the Great Southern Land – Gondwana, which was originally made up of all the southern landmasses plus India. It is quite possible that dinosaurs very similar to the Bass Coast dinosaurs lived in Antarctica, but because of the current thick layers of ice on that Continent, their remains are difficult to find.

The fossilised bones of many different animals that lived in this area have been found alongside the dinosaur bones. The most common animals were fresh water fish and turtles that lived in the rivers that flowed in the rift valley. There is also evidence of fresh water plesiosaurs, flying pterosaurs, birds, amphibians, crustaceans, a variety of insects and even a giant flea (!) as well as three groups of mammals – monotremes, tribosphenic mammals and multituberculates.

Bass Coast is the only place in Australia where three different groups of Early Cretaceous mammals have been found in association with dinosaur bones. The tiny tribosphenic mammals (Ausktribosphenos nyktos, Bishops whitmorei and Kryoparvis gerriti) were the size of small shrews and looked very similar to modern day placental mammals. One may have been the smallest mammal that has ever lived. The monotreme Teinolophos trusleri is the oldest and smallest monotreme in Australia. The multituberculate mammal Corriebataar marywaltersae, represented by two partial lower jaws, is the oldest evidence of this group of primitive mammals in the Southern Hemisphere.