Once a great valley home to the local Mirriwung Gajjerong people, then the site of the first cattle station in the East Kimberley with the massive Ord River flooding the plains during the wet season, this area has now become the largest reservoir of freshwater in Australia when in flood. Second only to Lake Pedder in Tasmania at normal supply level!
Fertile plains in the east running to rugged red ranges in the west now covered by 1000 square km of drinkable fresh water. Scattered throughout these plains were a number of small to medium sized hills which have now become islands in the lake. There are over 70 islands ranging from small rocky outcrops to the largest island – Hagan Island – approximately 7 km long, 3 km wide with the tallest peak (Mt Misery) rising over 200 metres above the lake.
Prior to the lake filling, the Ord River only flowed during the wet season from December to March. For the rest of the year only an ever decreasing chain of waterholes existed. Inhabiting these water holes was an abundance of life living in the water or visiting regularly for the necessary supply of freshwater.
26 species of fish were recorded, three varieties of freshwater tortoise, Johnstone River Freshwater Crocodiles, Merten’s Water Monitors, many species of birds marsupials, amphibians etc.
Due to the limited supplies of freshwater in the dry season, the populations of most of these animals was very limited. As the lake filled in the early 1970’s many animals perished in the flooding (many were rescued – Ord Noah pics), but then others thrived.
As far as it is known, all 26 species of fish have survived, the original count of 350 crocodiles has increased to an estimated 35,000 and the birdlife has increased over a thousand fold.
In summary the filling of Lake Argyle has created more than it destroyed with respect to the variety and population of the wildlife, the lake has developed into a very unique ecosystem!
You can find populations of marsupials living on islands that have been totally isolated for almost 40 years. In May and June every year, thousands of crocodiles begin to dig their nests on the islands and then in November, tens of thousands of crocodile hatchlings begin to emerge from their eggs. In September, thousands of migratory wader birds begin to arrive from northern hemisphere as they fly south to escape the northern winter. During March and April at the end of the wet season, millions of Golden Orb Weaver Spiders and the smaller Basket Spiders begin to construct enormous webs to capture the insects that have multiplied in their billions during the wet season. It is not unusual to see entire trees and rocky outcrops totally smothered in spider’s webs.