Geography

3A. Brown pigeon

3B. Green catbird

All of these birds occupy different niches in the rainforest, with species dwelling on the forest floor tending to be those that live only in the rainforest.

The most prominent birds in the rainforest are the pigeons, of which five species occur in Minnamurra. These include the wonga pigeon and the emerald dove, which feed on fallen fruit on the rainforest floor. You are more likely to hear and see the wonga pigeon than the emerald dove. The emerald dove, a forest floor dweller, has been badly affected by the introduction of feral species such as the cat and fox, which feed on these birds. You might hear the wonga pigeon with its booming call and clapping wings as it moves off the forest floor.

Other forest floor species include the superb lyrebird, which can also live in drier eucalypt forests and can be heard loudly in the winter months when it is breeding; the pilotbird which follows along behind the lyrebird, looking for food in the leaf litter disturbed by the larger bird, making a distinctive "guinea-a-week" call; and the satin bowerbird, which can also be found outside the rainforest.

3C. Lewin's honeyeater

Many of these species live on the fruits of the rainforest trees, but some, such as the wonga pidgeon, the figbird, the australian kingparrot, the emerald dove, crimson rosella, and the pied currawong have adapted to be able to make use of introduced species of plants, such as privet, camphor laurel, lantana, ink weed and wild tobacco. This can mean in many cases that the natural processes of the trees reproducing through birds eating seed-filled fruit and dropping seeds in their faeces is now helping introduced weed species to spread throughout the rainforest.

Fieldwork activities

• Look at the food web. What are the elements of the forest that would be connected to the diversity of birdlife? (H12)
• The rainforest contains a large diversity of birds. What major factor do you think is linked to the diversity of birds in the area? [Hint: diversity of flora and climate.] (H12)
• What characteristics do the birds have that allow them to live in the canopy, sub-canopy (middle layer) and forest floor? (H12)

Click to hear the birds

The other fauna in the rainforest include mammals, reptiles and insect species. These species live in the rainforest but can also be found in other locations. Sadly many of the species that are more specific to the rainforest have been made rare or extinct by the removal of 75% of the rainforest since Europeans arrived.

Various marsupials can be found throughout Minnamurra, with the brown antechinus being one of the most common. The dusky antechinus is also found in the area. This species of animal is interesting because of its life cycle; all the males of the species live for only around 11 months, dying in late winter following mating.

Possums are another common marsupial found in the area, with the Brushtail Possum being the most frequently seen. Other species in Minnamurra include the Mountain Brushtail, the Ringtail Possum, the Greater Glider and the Sugar Glider.

Other mammals and marsupials found in the rainforest include wombats, echidnas, water rats, bush rats and swamp rats and, of course, the feral introduced species, such as the black rat, the house mouse, the cat and the fox.

Reptiles and amphibians are generally not restricted just to the rainforest and tend to be found in other places outside the rainforest. Several species of frog live in Minnamurra Rainforest, with the leaf green tree frog being the most common, whilst the barred frog, the great barred frog and the giant barred frog are all restricted to the rainforest, although they are fairly rare. Like frogs all around the world, the number of frogs in the rainforest is dwindling for, as yet, an unknown reason.

Other reptiles include snakes, with the eastern tiger and red-bellied black snakes being extremely venomous as well as common in Minnamurra. The harmless but more common diamond python has been affected by the disappearing habitat and over-enthusiastic collectors.

3D. Eastern water dragon

Invertebrate species, consisting of insects in the rainforest, are generally restricted to mainly beetles, butterflies, moths and flies, with butterflies and moths being the most common insects found in the rainforest.

Butterflies, because they tend to be linked closely to the vegetation on which their larvae feed, are often restricted to the rainforest if the species of plant they eat exists only in that ecosystem. There are 25 known rainforest species of butterfly in this area; however it is not known how many are present in Minnamurra.

All of these animals are dependent on each other and the other parts of the ecosystem for their survival. In turn, they act to help ensure the survival of the ecosystem. A food chain is a basic way of demonstrating the connection between the biospherical components of the ecosystem, with a food web being a more complex demonstration of the same concept. This is the major biogeographical process that occurs with fauna in the rainforest. Large changes to the food web of the rainforest could affect the rainforest's existence just as changes to plant species or climate would.

Fieldwork activities

• Carefully study the food web and, using the list of other animals in the rainforest, build this into a more complex food web.(H8/H13)
• Look at list of other animals in the rainforest; note that some of the animals are rare, and some are common. What factors do you think have caused some animals to continue to be common whilst others are now rare?(H12)
• What impact have the introduced species on the list of other animals in the rainforest had on both the plants and animals of the rainforest?(H12)