Alkoomie has the northernmost limestone caves in Queensland and, together with some smaller caves on Kings Plains Station, the only limestone caves on Cape York. The caves occur in an area called Melody Rocks and extend over an area around 3km long and 500 metres wise.
There are three major karst towers where the limestone rises sharply above the surrounding rainforest canopy. In between these are areas that would once have been towers but have eroded away to form extremely rugged areas of limestone boulders and other karst features within the rainforest.
Due to the monsoonal climate the limestone has weathered into spectacular razor sharp spires that soar out of the surrounding rainforest. While the topography is so rough that much of the limestone area remains unexplored, the local Godmans Rock Wallabies seem to have no difficulty at all making their way from spire to spire.
The limestone is honeycombed with caves. These range from very large chambers to tortuous tight passageways that pass deep into the rock. Large or small, the caves are home to an incredibly diverse range of fauna including a large number of bat species. While bat research at Melody Rocks is still in its early days at least four endangered or threatened species have already been found living there. These bats species are:
- the iconic Ghost Bat
- Semons Leaf-nosed Bat
- Greater Large-eared Horseshoe Bat
- Diadema Leaf-nosed Bat
The caves are also home for several colonies of a remarkable bird, the Australian Swiftlet. This is also a protected species. The Swiftlets are small birds that are able to navigate in total darkness as they have a form of echolocation whereby they can navigate by way of reflected sound. It is an amazing sight to see the birds flying at full speed seemingly straight into a rock face only to discover a tiny hole down which they are disappearing. They nest in total darkness and can fly along passageways so small that even the thinnest of cavers can't navigate.
The limestone also features a unique form of rainforest that has been recognised by the Australian Tropical Herbarium as a new endangered regional ecosystem. At least eight threatened or near threatened plants grow in the rainforest. In addition, a recent expedition discovered the first ever Australian occurrence of a fern previously only found in association with limestone in South East Asia.
Unfortunately the Queensland Government is considering an application to mine the limestone. If approved a truly unique national treasure would be lost forever.