Dugongs

From EnvironmentWiki

By Jennifer Marohasy

Closely related to elephants, dugongs live up to 70 years and feed in shallow coastal waters mostly on seagrass.

1 Population Numbers
2 Indigenous Harvest
3 Animal Welfare
4 Campaigning
5 Acknowledgement
6 References

Population Numbers

Dugongs have a wide distribution throughout the Indian Ocean and south west Pacific but populations are now considered rare over much of this range and extinct in the waters around Mauritius and the Maldives. Dugongs are listed as a threatened species vulnerable to extinction (IUCN Red List, 2008).

The highest densities and largest populations are thought to occur along the west coast of Australia in particular at Shark Bay, Ningaloo Reef and Exmouth Gulf. It has been estimated there are 85,000 dugongs in Australian waters. The total global population is unknown.^[1]

Indigenous Harvest

Over-hunting is considered a threat to dugong populations.

A National Recreational and Indigenous Fishing Survey in Australia estimated that 1,619 dugongs are harvested each year in Australian water (Henry and Lyle, 2003).

This figure is dispute by Helene Marsh who has commented that: about 1,000 dugongs per annum is a rough estimate of the harvest in the Torres Strait region including Papua and New Guinea; that there are no accurate figures for other areas; that the figures quoted in the National Recreational and Indigenous fishing survey in 2001 are questionable because of the low sampling fraction and the lack of standard errors.

Professor Marsh has also commented that it is not necessary to quantify how many dugongs are being harpooned each year as part of the Indigenous catch and that there are healthy stocks of the marine mammal in northern Australian waters. Furthermore, she advocates a bottom up approach to conservation and that a range of management tools could be applied to improve the sustainability of Indigenous dugong harvesting by working with communities including: some communities may choose to regulate catches, some communities may choose to have closed seasons; other communities may choose to have closed areas, other communities may want to you some sort of gear restrictions.

Animal Welfare

It is unclear how long it takes a dugong that has been speared or harpooned to die.

Indigenous Australians have protested RSPCA allegations of cruelty to a dugong caught in water off Woodgate, south of Bundaberg, chanting and waving a placard that read "You took our land, don't take our culture" outside the Childers magistrate court in September 2004.

Campaigning

Helene Marsh was the assessor for the inclusion of dugongs in the IUCN Red List of Threatened species and is a member of the Technical Advisory Committee for the NAILSMA Turtle and Dugong Project. In 2004, Professor Marsh commented that “co-management arrangements for indigenous hunting in Torres Strait must be progressed as a matter of urgency, if Australia is to honour its international commitments to conserve dugongs and dugong hunting cultures” (Animal Conservation 7: 435-443). In 2008, Professor Marsh commented that “significant progress is being made as a result of the efforts of NAILSMA and the Torres Strait Regional Authority supported by significant funding from the Australian government in accordance with its National Partnership Policy" (Blog comment ) Professor Marsh has a website with reports and technical papers.

Jennifer Marohasy has written on the issue of indigenous harvesting of dugongs in Australian waters suggesting that it is hypocritical of Australians to rally against the whaling by the Japanese while ignoring the slaughter of dugongs by Aborigines and Torres Strait Islanders. In this context Dr Marohasy has suggested that there are two criteria which should be applied to the harvest of an animal species: 1. Are the numbers taken sustainable, and 2. Is the method of killing humane.

Dugongs featured in the World Wide Fund for Nature (WWF) 'Save the Great Barrier Reef Campaign' which was launched on World Environment Day in Brisbane, Australia, in 2001. As part of this campaign it was incorrectly suggested that Australian sugarcane farmers were killing dugongs through their unsustainable farming practices in particular the use of pesticides. This allegation was based on a claim by Great Barrier Reef Marine Park Authority (GBRMP) researcher David Haynes that dioxin found in dugongs autopsied after they were drown in fishing nets off the Queensland coast could be linked to sugarcane production, however, the dioxin was subsequently found to be naturally occuring and widespread in coastal Queensland.