Nature, culture and history
Mount Lewis National Park is a 'hotspot' for animal diversity and endemicity.
Red and blue spiny crayfish
Fifteen species of spiny mountain crayfish have been identified in Queensland, living in cold, fast-flowing streams. In south-east Queensland, suitably cold habitat is found as low as 250 m. The further north the crayfish are found, the higher their lower limits, until they are found only above 800 m in North Queensland. Each mountain range has its own species of spiny crayfish and genetic samples have confirmed that all have a common ancestor. It is believed that this ancestral crayfish expanded its range into Queensland over 5,000,000 yrs ago, when temperatures were cooler and rainforest more extensive. With climate change came a contraction and fragmentation of forest habitat, resulting in different mountain top populations separating and evolving into different species. The Mount Lewis spiny crayfish (Euastacus fleckeri) is bright blue and red and is active during the day. Look for them in flowing creek crossings.
Only found in mist-draped rainforest above 900 m altitude in north-east Queensland, the golden bowerbird is Australia’s only representative of a group of maypole-building bowerbirds found also in New Guinea. Rich, golden-yellow and olive-brown, the males of this species live in loose clans, with as many as 10–15 birds living in an area of 40–50 ha. Although the golden bowerbird is the smallest of the Australian bowerbirds, it builds the biggest bower.
Bowers are display areas built by male bowerbirds to attract females for mating. The male golden bowerbird keeps his bower site year after year, defending, tending, refurbishing and extending the bower through most months. The two towers of the bower, from 1–3 m high, are made from twigs, glued with saliva and adorned with moss, grey-green lichens, pale flowers and fruit. The towers are built around two saplings, about 1 m apart, and bridged by a low branch or buttress, from which the male displays.
Huge blue earthworms
Some of the largest earthworms in the world are found in the Wet Tropics. One in particular, Terriswalkerius terrareginae, is a deep blue colour and is reported to grow up to 2 m long! It has been found at various locations in the Wet Tropics, including Mount Lewis. These large earthworms are often forced from their flooded burrows after heavy and prolonged rain. Look for them on the forest floor, roads and tracks during these times.
Ringtails from the Daintree
The Daintree River ringtail possum (Pseudochirulus cinereus) is very similar to the Herbert River ringtail possum but the adults retain the pale juvenile colour. The two possums have separate distributions; the Daintree species occupying an area to the north of the 'Herbie’s' range. They were recognised as different species only in 1989 on the basis of having different chromosome numbers. The Daintree River ringtail possum is primarily nocturnal but there have been occasional sightings of animals moving about during the mid-afternoon.
The masked white-tailed rat (Uromys hadrourus) is the only rat endemic to the Wet Tropics. Discovered at Thorntons Peak in 1973, specimens of the masked white-tailed rat have also been found above 550 m on Mount Carbine, Mount Lewis and Lamins Hill. These records indicate that the species probably occurs throughout the Atherton uplands, between Kuranda and the Herbert River gorge, west of Ingham. Little is known about the habits of the masked white-tailed rat in the wild although they are known to eat rainforest fruit and insects, especially larger beetles. They are also reasonably vocal, emitting a raspy honking call, when disturbed.
Snakes with red bellies
The venomous red-bellied black snake (Pseudechis porphyriacus), a dark snake with a white to red belly, is usually found around water and damp forests where it feeds on aquatic animals and small mammals and reptiles. Along the Mount Lewis Road they are often seen basking in the sun. They are quick to retreat and, if cornered, tend to make bluff attacks so as not to waste venom. Do not approach these or any other snakes.
Blue faces in the forest
Blue-faced parrot-finches (Erythrura trichroa) can be seen on Mount Lewis during the summer months. These large finches are seed-eaters, finding their food in rainforest trees, shrubbery and glades within the forest. The male of the species is grass-green with a cobalt-blue face and throat, and red rump. The females are slightly duller, with less blue on the head. Blue-faced parrot-finches are social birds with flocks of up to 20 or 30 birds—both adults and juveniles—sometimes reuniting after breeding. The flocks fly with swift directness, coordinating their movements in unison. Although they do not cluster on perches, groups build roost nests in which they cram to sleep.
Rapid declines in Australian rainforest frog populations were first noticed in 1979 in south-east Queensland. The disappearances continued through until the mid 1990s and included rainforest areas in mid-east and north-east Queensland. In the Wet Tropics, seven species endemic to the area declined or disappeared in the early 1990s, and three remain missing. Three of these species are found in Mount Lewis National Park—the tapping green eyed frog (Litoria serrata), waterfall frog (Litoria nannotis) and common mistfrog (Litoria rheocola). The latter two are only known from a single location in open forest adjacent to the rainforest. All rainforest populations have disappeared. The reason for these catastrophic declines is chytridiomycosis, a disease caused by the amphibian chytrid fungus Batrachochytrium dendrobatidis.
Mount Lewis microhylids
Microhylid frogs are a family of small, litter-dwelling frogs found in many areas of the world. In Australia, their highest diversity is in the Wet Tropics. Six microhylid frog species, out of a total of 13 Wet Tropics microhylids, are found in Mount Lewis National Park. Two of these, the mountain nurseryfrog (Cophixalus monticola) and rattling nurseryfrog (C. hosmeri), are endemic to the area. The mountain nurseryfrog is also restricted to rainforest areas above 1100 m.
The large tadpoles in Mount Lewis’s many creeks belong to the northern barred frog (Mixophyes carbinensis), a recently described species. This mottled brown, robust frog is restricted to the high altitude rainforests of Mount Carbine and Windsor tablelands.
Rocks, volcanoes and soil
The big picture
About 420 million years ago, when Australia was still a part of the ancient continent of Gondwana, the east coast was 20–150 km inland of the present coastline. A trip to present day Chillagoe would have entailed a boat ride because it was well under water. Over time, rivers running off the continent carried bits of land into the sea in the form of gravel, sand and clay. Over a period of about 60 million years this material accumulated in an undersea basin known as the Hodgkinson Basin.
About 360 million years ago these sediments were caught in a squeeze and were compressed, folded and lifted far above the sea level, creating a series of mountain ranges that would rival today’s Andes or Himalayas in height. Sand, mud and gravel formed mountain ranges, transformed into metamorphic rocks by immense pressure and heat. These are the rocks that form much of the landscape we see in the Wet Tropics today.
From 310 to 260 million years ago other events deep in the earth’s crust caused further changes in the landscape. Large pools of molten rock (magma) pushed up into the crust. In many places they did not make it to the surface, instead slowly cooling and solidifying to form bodies of granite deep underground.
For over 100 million years there were no dramatic geological changes in the Wet Tropics’ region. Instead, it was a long, stable period where mountains continued to rise but were also subjected to the persistent processes of erosion. Gradually the granite, once deep below the surface, was exposed and the covering rocks were weathered.
The next distinct chapter in the geological story of the Wet Tropics was a violent volcanic one, which was particularly forceful on the Atherton Tableland. From about seven million years ago vast amounts of lava flowed from a number of shield volcanoes, spreading over much of the landscape and cooling to form a dense layer of basalt.
The geological connection
Geology and resulting soils, altitude, aspect and rainfall, determine the forest type found in different areas along this drive. Basalt creates the most fertile soil. Granites and metamorphic rocks are more acidic and their soils less fertile. The soils throughout most of the drive are derived from granites, while at the very start of the drive they are derived from the older metamorphics of the Hodgkinson Basin.
Forest in the clouds
As the road ascends and the temperature drops, the composition and features of the forest change gradually. The leaf size, forest height and species-richness are reduced. Wait-a-while (Calamus sp.), a climbing palm, is gradually replaced by the Atherton mist palm (Lacospadix australasica), orania palm (Oraniopsis appendiculata) and the purple-crowned archontophoenix (Archontophoenix purpurea), a type of Alexandra palm.
At 900 m altitude, the road enters cloud forest, so named because the forest is often shrouded in cloud, mist and fog. The high moisture level and cool year-round temperatures foster plant communities rich in mosses, ferns and epiphytes.
Cloud forests harvest water directly from clouds, fog, mist and rain. This, and the fact that they use comparatively little water, means they contribute a much higher volume of water to catchments than lower altitude rainforest. Like giant sponges, they capture large volumes of water and release it slowly throughout the year. For this reason, cloud forests are believed to be of great importance to the maintenance of stream flows throughout the dry season.
Even though cloud forests only cover a small area of the Wet Tropics, their world-wide ecological importance is evident. In some countries, cloud forests are under threat from development and agriculture. The threat from global warming, which predicts an increase of one to two degrees in temperature over 50 yrs, would cause the cloud base to rise in altitude. In the Wet Tropics, this would result in a predicted loss of about 75 per cent (70,000 ha) of Queensland’s cloud forests.
Mount Lewis National Park is within the Wet Tropics World Heritage Area (WTWHA). Proclaimed in 1988, the WTWHA extends for about 450 km between Cooktown and Townsville. Consisting of nearly 900,000 ha, vegetation is primarily tropical rainforest, but also includes open eucalypt forest, wetlands and mangrove forests. The WTWHA meets all four natural criteria for World Heritage listing. These criteria recognise the area’s exceptional natural beauty and the importance of its biological diversity and evolutionary history, including habitats for numerous threatened species. The WTWHA also has cultural significance for Aboriginal people who have traditional links with the area and its surrounds.
For more information visit the Wet Tropics Management Authority.
Culture and history
Scratching for tin
Tin and wolfram (tungsten) were mined in the Mount Lewis area for over 100 yrs. Most of the tin was alluvial, collected straight from the many mountain creeks and streams. The rest of the minerals were worked from rock veins and quartz reefs.
Pack teams brought in stores and carried out the minerals along a gently graded track that zigzagged up the side of the mountain. A settlement of tin shacks was established and the area was grassed to supply feed for horses and stock. Other shacks dotted the slopes of the mountain as each of the scratchers established a claim.
In 1963 Paddy Bethel and his sons Jim, Don, Jack and Roy started a tin mine on Mount Lewis. The races, built by the old tin scratchers, were renewed with half drums and bridges replacing some of the old trenching. The water for the mine came from dams and was gravity-fed for hundreds of metres along the trenches. Just before the mine the water entered a pipe, providing the necessary pressure (80 lb/in2) for the works. The first-class tin product (74 per cent tin) was bagged into 100 weight bags and trucked down the Rex Range to Cairns.
The mine employed around 10 people, operating 14 hrs a day for up to seven days a week. The continuing wet weather and big trees obstructing access to the tin eventually forced JP Bethel and Sons to move its mine to Bethels Crossing on the Mitchell River at Mount Carbine in 1966.
Around the same time that the tin and wolfram were being mined on the upper slopes, ad hoc timber harvesting of red cedar and kauri pine was occurring on the lower slopes of Mount Lewis. The timber was cut by hand and taken by bullock teams to Mount Molloy for milling.
The first part of the Mount Lewis Road was put in during the late 1940s or early 1950s for contractors to access timber higher up the slopes. Tom Curly lived in a roadside shack and was responsible for maintaining the condition of the road. He used to walk along with a shovel, turning away any water that had failed to run off.
Many contractors worked the Mount Lewis slopes over the years and initially all the timber was consigned to the Mount Molloy Mill. When the Rankine family took over, they sent the timber far and wide.
The road was extended over the years and harvesting continued on the upper slopes until 1978. On the lower slopes the wet sclerophyll areas were harvested until the declaration of the Wet Tropics World Heritage Area in 1988.
In July 1967 bad weather caused a light plane to crash on the slopes of Mount Lewis. Teams of locals, police and the Army searched for weeks. It wasn’t until 12 months later that the crash site was located, quite close to the existing road. There was barely any damage to the surrounding vegetation but the plane had left a crater in the ground, over 1 m deep.
The Traditional Owners have a deep respect for nature and an intimate knowledge of its cycles. They are part of their country, as their country is a part of them. They believe that nature and culture cannot be separated or viewed separately as they are inextricably bound.
Throughout this country there is a network of story places, sacred sites and Dreamtime legends.
- Seasonal closure of Mt Lewis Road, Mount Lewis National Park 4 January to 1 April 2022