Rainforest Natural History Excursions
The World Heritage rainforests of the wet tropics region are recognized as one of the most ecologically rich and evolutionarily significant sites in the world. Encompassing a mere 0.3 percent of the continent’s area, these restricted forests support the highest assemblage of biological diversity and endemism found within Australia, including:
- 30% of the frog and 23% of the reptile species
- 36% of the mammal and 60% of the bat species
- 62% of the butterfly and 18% of the bird species
- 65% of the fern and 30% of the orchid species
- 37% of the conifer species
- 37% of the freshwater fish species
- 54 species of vertebrate animals unique to the region
The animals and plants of Queensland’s tropical rainforests are associated with eight major stages in the earth’s evolutionary history. Relic species such as the musky rat-kangaroo provide evidence of the origins of Australia’s marsupials, while high concentrations of primitive flowering plants hold the secrets to the emergence of all terrestrial plants.
Of the 19 primitive families of angiosperms (flowering plants), 13 are found within the tropical rainforests of the wet tropics region. One of these, a vine called Austrobaileya scandens, is of particular scientific interest because its pollen resembles that of the oldest known fossil pollen.
These tropical rainforests now cover about 7,500 square kilometres, half of their original area, representing a relic of an ancient forest that once covered most of the Australian continent. Thirteen distinct rainforest types are currently recognized, occurring in four main altitudinal zones: lowlands, foothills, uplands and highlands. Within these rainforests exist an amazing array of plant life. In some of the cooler forests, mosses, lichens, epiphytic fern and orchids adorn the trunks and branches while vines and lianas snake skywards toward the canopy. Trees with impressive buttress root formations, often spanning many metres across, are characteristic of several other rainforest types. Another unusual feature seen in a number of tree families is the habit of producing flowers and fruits directly from the trunk (cauliflory) and branches (ramiflory). In addition, palms, ancient cycads, gingers and cordylines are found within the understory of certain rainforests.
The lowland rainforests are the most botanically diverse, while the cooler and often misty upland and highland forests contain the greatest concentrations of arboreal mammals. Species such as Bennett’s and Lumholtz’s tree-kangaroo, lemuroid, Herbert River, Daintree and green ringtail and long-tailed pygmy possums are endemic to the region.
Representing another ancient group, the southern cassowary, an
endangered species, is now restricted to the larger remnants of wet
tropical rainforest. Other species that inhabit these rainforests
include: Boyd’s forest dragon, northern leaf-tailed and chameleon
geckos, amethystine python, prickly forest skink, northern barred,
green-eyed and orange-thighed tree frogs. Hercules moths, giant stick
insects and mantids and a multitude of other invertebrates creatures are
also common.
Wild Watch excursions provide an unparalleled opportunity to explore and appreciate the beauty and complexity of these rainforests.