The Dolphin Watch project launched by the Trust in April 2009 focuses on one of the Swan Canning Riverpark’s most iconic species.
This section includes the following:
- Background to the project
- Recent Swan River dolphin deaths investigated
- How to care for our dolphins
- How to identify a dolphin/id sheet
- Volunteering for the Dolphin Watch program
- How can I get involved?
Dr Hugh Finn and Dr Carly Palmer from Murdoch University, and Dr Chandra Salgado from Curtin University are leading the research into Perth’s Swan River dolphin community and investigating how environmental changes in the river and human activities can affect the dolphin community.
The research project builds on previous research conducted in 2002-03. It works with the Trust’s River Guardians community engagement program to monitor the movement and behaviour of the dolphins.
Community involvement is a great boost to the research project and allows information to be gathered on how dolphins use the Canning and upper reaches of the Swan River – areas that experience problems such as low oxygen and algal blooms.
Recognising the dolphins potential as indicators of river health, the project aims to provide information on dolphin ecology and interactions with human activities in the Swan and Canning rivers, upstream of Perth waters. It will provide a comprehensive understanding of the Swan River dolphin community and the effects of human activities on the mammals.
Dolphins playing in the rivers are an iconic and much loved sight but the mammals’ habitat and community could be at risk. The Swan River dolphin community is small, dependent on a handful of females and living in an urban environment which places a lot of stress on the mammals. Pressures from loss of habitat, increased river usage by boats and other motorised vessels, climate change, entanglement, boat strikes and noise all impact the community.
The Trust continues to urge the Perth public to look after the Riverpark to minimise stress on the dolphins. The public can play an essential role in monitoring this iconic species. Becoming a member of the Dolphin Watch program is a way the community can get directly involved in looking after these iconic mammals.
Recent Swan River dolphin deaths investigated
The Trust together with the Department of Environment and Conservation are working in collaboration with Curtin and Murdoch universities to investigate six dolphin deaths in the Swan Canning Riverpark during the past four months.
Post mortem investigations are not conclusive but indicate the dolphins had suppressed immune systems and bacterial, fungal and viral infections.
Recent media reports have linked the deaths to elevated levels of the banned pesticide dieldrin in the dolphins. While it is possible long-term exposure to contaminants may have contributed to the deaths, the Trust and researchers are continuing to investigate a suite of factors.
How to care for our dolphins
- Keep your distance – never approach a wild dolphin and make sure you keep at least 30 metres away if you are in the water or 100 metres if you are in a boat.
- Brake for dolphins - dolphins often form resting groups in the middle reaches of the estuary, so keep an eye out for dolphins, and slow down if you spot any.
- Never feed dolphins – it is illegal and leaves them vulnerable to entanglement, boat strikes, and disease.
- Fish responsibly - dolphins, particularly calves, can get tangled in fishing line. Make sure you dispose of unwanted fishing line in a proper rubbish bin or use a biodegradable line.
How to identify a dolphin
Previous research of the Swan River dolphin community discovered a community of approximately 25 dolphins in the Swan River that use the river almost every day.
This group includes several adult females with dependent calves, one or two ‘alliances’ of tightly-bonded adult males, and a large group of sociable youngsters. The research indicates that many, if not all the Swan River dolphin community are likely to have grown up in the Swan River and have local knowledge that is important to their survival. These dolphins are likely to know where the fish are available to eat and return to these spots regularly.
The research identified the dolphins by the distinctive shape of their dorsal fins and collected valuable information about their range, habitat, behaviour and feeding. The Dolphin Watch program has an identification chart of the Swan River dolphin community’s dorsal fins that helps volunteers to identify sighting of these mammals.
Volunteering for the Dolphin Watch program
Dolphin Watch is open to members of River Guardians, the Trust’s community engagement program which connects the community with the Swan Canning Riverpark. Training is provided and volunteers learn how to record the time, date, location of dolphin sightings, number of dolphins sighted, presence of a calf, which way the dolphins were travelling, and any noticeable behaviour.
Volunteers are trained in basic observation techniques and how to ‘observe but not disturb’, in keeping with regulations in the Wildlife Conservation Act 1950 and Department of Environment and Conservation protocols for marine mammal interaction. Shore-based observations are ideal as volunteers can observe animals closely without the dolphins knowing they are present.
Dolphin Watch volunteers make a valuable contribution to scientific research, while gaining skills and networking with others involved in caring for the rivers.
How can I get involved?
Become a River Guardian.
To express your interest in participating in the next Dolphin Watch training day contact us at riverguardians@dec.wa.gov.au.