Seal and seabird research
Wilsons Promontory is recognised as being an important transitional marine area between different habitat types. There are over 20 islands in this area which provide important breeding locations for seabirds and Australian fur seals. The islands are also home to many unique terrestrial plants and animals which display vastly different ecologies to their mainland counterparts. Consequently, studying these populations is vital for monitoring the response of the Bass Strait ecosystem and the island habitats to environmental perturbations such as climate change.
Parks Victoria, in collaboration with Deakin University, has conducted extensive research into seals and seabirds at Wilsons Promontory Marine National Park and Wilsons Promontory National Park. This research explored a variety of questions relating to fur seal physiology, genetic structure of the population, disease, population increase and foraging behaviours, as well as seabird abundance and distribution. Below are updates on two completed components of this project.
This study aimed to investigate the abundance, distribution and diversity of seabirds on 15 of Wilsons Promontory’s offshore islands.
The intensive survey techniques were preformed in both summer and winter from 2008 until 2011 to ensure both winter and summer breeding seasons were accounted for.
Results indicated that an estimated 839,034 short tail shearwater, 26,146 little penguin, 19,025 common diving petrel and 4,082 fairy prion breeding pairs occur in the region. Previous abundances for most species is not available, however for the short tail shearwater, the estimated number of breeding pairs represents a decline of 36 per cent.
The information gained from this project is essential to understand seabird ecology within the Bass Strait ecosystem as well as providing information for monitoring and managing the populations.
Ecotourism and Australian Fur Seals
Ecotourism is a sustainable form of tourism, usually focussed on spreading messages relating to environmental education and conservation. However, many types of tourism (including ecotourism) can increase the exposure of wildlife to humans. This can result in changes such as increased vigilance, decreased foraging efficiency, increased predation, decreased breeding success and direct injury or mortality. Australian fur seals are one of the least abundant species of fur seals in the world and ecotourism involving Australian fur seals is very popular. For management purposes, it is important to know the effect of tourist boats on seal behaviour.
The study found that seals resident on the islands in Wilsons Promontory are affected by the approach of boats. Seal attendance and seal behaviour are more strongly affected with closer boat approaches, approaches in the morning and approaches in the summer post-breeding period. Colonies which are exposed to more regular boat traffic (e.g. at Seal Rocks) are less responsive to boats, however this exposure needs to remain relatively constant. Frequent exposure to boats at the Prom is undesirable as the increase in boat presence is likely to have other negative impacts on the environment.
These results are particularly useful for park managers so they can ensure that ecotourism and other vessel movements have minimal effect on seal colonies.