Impacts of feral pigs on tropical freshwater ecosystems
The Department of the Environment, Water, Heritage and the Arts (Australian Government) funded the study titled Impacts of Feral Pigs on Tropical Freshwater Ecosystems to investigate and obtain scientific evidence to quantify:
- feral pig impacts on the biodiversity of ephemeral lagoons
- the relationship between pig ecological impacts and pig abundance.
The study investigated and obtained scientific evidence about feral pig impacts on the biodiversity of ephemeral lagoons in tropical freshwater systems, and the relationship between pig ecological impacts and pig abundance. It was conducted in north Queensland at Lakefield National Park.
The project found that overall, feral pig activity had a negative impact on the ecological condition of ephemeral lagoons with the major impacts related to destruction of habitat and a reduction in water clarity.
Pig foraging activities caused major destruction to aquatic macrophyte communities. There was a demonstrated positive association of pig abundance with the extent of impact (pig diggings). The study identified an exponential concave up curve to the abundance / impact relationship. The point on this relationship curve where the minimal level of population control required to maximise impact reduction appears to be approximately 50% visitation frequency on plots.
There was a significant positive association of the Aquatic Vegetation Index and pig abundance increased with increasing aquatic vegetation abundance. This illustrated that resource availability may be the dominant influence on the level of pig impacts. Pigs concentrate their impacts where adequate resources are present.