ENVS Undergrads Joshua Temes and Malia Cedar are studying abroad on an SIT Australia: Rainforest, Reef, and Cultural ecology trip. This is their final project for one segment of their trip.
By Josh Temes, Emily Mucha, Malia Cedar, Elena Smith
Walking through study sites in the lush Australian rainforest is just a little bit different than sitting in lecture. Our classroom includes giant tree ferns, one freshwater crocodile, and too many sawtooth turtles to count. As part of a four-month study abroad program through School of International Training called Rainforest, Reef, and Cultural Ecology, we are lucky enough to visit some incredibly beautiful places around Australia. We’ve interacted with the local townspeople, learned about Australian culture, and hiked to some stunning waterfalls and canopy-top views. We also get to conduct some pretty interesting observational studies on Australia’s exotic animals.
For this project, we surveyed and analyzed the abundance and distribution of the Australian brush-turkey population around Lake Eacham in Queensland, Australia. Although they certainly look similar, they aren't related to American turkeys! Australian brush-turkeys (Alectura lathami) are large black birds with a red-tinged, bald head and black feathers. Brush-turkeys are megapodes, or mound-building birds found down the eastern coast of Australia. They don’t sit on their eggs to incubate them, but rather rely on mounds that they build of decaying vegetation to keep the eggs warm. In the last few decades, the population of this interesting bird has become increasingly fragmented due to habitat destruction and hunting. As more houses and communities have been built further into natural areas, these birds are interacting much more with humans, often in increasingly negative ways. Brush-turkeys are prolific omnivores and will eat anything, including pet food left outside, compost piles, and have been known to destroy flower gardens in search of food. These birds were once nearing endangerment, but have since recovered and now are ubiquitous across this area.
As there has been hardly any research conducted on the brush-turkeys in this region of Northern Queensland, the purpose of our project was to conduct a survey of the locations and numbers of animals around Lake Eacham. Lake Eacham is a beautiful crater lake encircled by dense rainforest situated in the Crater Lakes National Park, a World Heritage listed site located in the Atherton Tablelands. This brush-turkey survey took place in the complex vine forest lined with labyrinthine fig trees, pandanus, tree ferns, and vines that Tarzan would be happy swinging from. Our task, completed with our classmates, was to split up into five separate groups and monitor five different sites. The study areas consisted of: a recreational area swarming with picnickers, trails cutting through the park’s rainforest and a residential road bordering the park.
Throughout our study and time traveling through this area, the effect of forest fragmentation and human activity on natural habitats was clearly displayed. Despite the expectation that brush-turkeys would congregate in areas that were less affected by human disturbance, our study showed that there was an ecologically significant increase in the average number of brush-turkeys seen in the public use site than in the natural and residential road sites. In the areas where there was continuous car traffic, the presence of brush-turkeys was extremely small, with the occasional single turkey seen foraging once or twice along the site. The presence of brush turkeys in the natural sites that were only disturbed by one walking track, was moderately higher with brush-turkeys seen in small groups of one or two and in different areas along the track. In the public use area that was broken up between both picnic areas and parking lots, the presence of brush turkeys was greater than both the residential road and natural sites. We saw an average number of seven brush-turkeys in the public use area, compared to two brush-turkeys in the natural sites, and one brush-turkey in the residential site.
The data collected in the public use site showed that when the picnic area was being used, the turkeys were often fed by picnickers or were able to pick up scraps of food that were left behind on vacant tables. The turkeys walked straight up to the tables on numerous occasions and were not afraid of human presence. Conversely, in the more natural study sites, the turkeys were often seen fleeing the area as soon as humans entered them. The dramatic behavioral differences between the turkeys found in the natural and public use sites coupled with the number of turkeys found at each site seemed to be the most significant findings from the study.
It became clear that the presence of brush-turkeys was tied to areas populated by humans. Public usage areas such as picnic spaces brought brush-turkeys in like a magnet, as they had easy access to food. A common misconception of the public is that feeding wildlife allows these species to better survive; since they are so persistent, they must be incredibly hungry, right? Not only this, but many think that feeding animals of natural environments helps to bring in more wildlife to the spaces where humans can readily observe them! To a typical citizen, it may appear to be a win-win situation on the outside, however, these types of actions can actually have negative effects for all types of animal populations.
While brush-turkeys can naturally be found inhabiting the lush Australian rainforest, the number of individuals we counted in these forested areas was noticeably lower than the number surrounding the picnic tables and the residential area. It appears that access to food and garbage artificially elevated the brush-turkey populations in these areas, drawing in a greater number than the environment is used to supporting, and concentrating them in one place. When humans aren’t around to provide their resources, the brush-turkeys are then forced to retreat into the forest, scraping areas clean of leaf-litter in order to look for food. With a large number of individuals carrying out this behavior, the forest floor is disrupted, displacing the insects that call this leaf-litter home. This can have implications for near threatened species higher in the food chain, such as fern wrens, as these animals depend on insects for supplementing their own diet. Also, exposing the soil dries it out, discouraging the growth of the plants and trees that make the rainforest as wondrous as it is! A high abundance of brush-turkeys can also affect human life, as they create messes by knocking over garbage cans, ripping up garden beds, and scaring away birds from household bird feeders.
These actions may give the brush-turkey the reputation of being a nuisance animal, but it’s important to take responsibility for our role in these types of situations. The interactions between humans and wildlife are complex; by studying these types of relationships and learning about the impacts of our actions on these species, we can become informed and responsible stewards of the environment.