A rise in human-related sea turtle deaths in Moreton Bay this year has hardened the Australian Marine Conservation Society’s (AMCS) resolve to seek amendments to Queensland’s marine park zoning legislation.
University of Queensland necropsies of dead Moreton Bay sea turtles have pointed to boat-strikes and litter as key causes of increasing mortalities.
UQ’s Moreton Bay Research Station (MBRS) co-manager and marine biologist Kathy Townsend said this week “the impact of rubbish ingestion is much higher than recorded in past years, while boat strike is still the principle cause of human induced mortality on sea turtles.”
Human related activities accounted for nearly one third of sea turtle deaths in Queensland in 2002. In 2007, Townsend found at least half of turtle mortalities around North Stradbroke Island had been due to human activity, with ingested rubbish mortalities doubling since last year.
She said many sea turtles contracted ‘floating disease’ when inorganic material such as wrap, balloons and plastic bottle caps were ingested into the sea turtle’s gut, creating a blockage which effects digestion and causes a gas build-up that left turtles buoyant, making it difficult for them to dive, feed, and vulnerable to predators.
“Boat strike is the final killing blow,” she said.
“Turtles are important for conservation, ecosystems and the tourism industry. Sea turtles world-wide are at risk of extinction, all species are listed as either vulnerable or endangered. They are an integral part of the marine ecosystem and more could be done to protect our local population.”
The Queensland Marine Parks Act 2004 secures less that 1% of the area of Moreton Bay Marine Park in highly protected, non-extractive green zones. Australian Marine Conservation Society campaigner Craig Bohm is calling for significant expansion of the area of highly protected, non-extractive green zones.
“Green zones will protect turtles,” he said.
“Right now, in October and November, turtles return to Moreton Bay to feed. They’ve been migrating from all over the place - some from as far as Mexico - and are weak and particularly vulnerable to human threat.”
“The AMCS wants the Queensland government to amend the Act to increase the number and size of green zones in Moreton Bay Marine Park to include at least 1/3 of each of the Park’s 16 aquatic habitats, for example, seagrass meadows, which are critical turtle habitats”.
Six of the world’s seven species of sea turtle have been found in Moreton Bay Marine Park. Of these, the hawksbill, green and loggerhead turtles live in the Park all year while others are occasional visitors to the Park. The loggerhead turtle is critically endangered and according to the EPA is facing local extinction in Queensland.
To accommodate deficits in the Act the AMCS asks boaties to “consider using propeller guards on boats to avoid striking turtles” and says “take your time, support our call for more green zones, and observe ‘go slow’ areas in the Bay.”
EPA stranding hotline 1300 130 372.
Craig Bohm - 07 3393 5811
The national Australian Marine Conservation Society is based in Manly, Brisbane. The AMCS is Australia’s peak marine conservation group and has operated nationally since 1965. It monitors and rescues marine species and marine environments. The AMCS has launched a pilot project to save turtles from unnecessary death by crab pots and other marine debris. The project involves locals working with scientists and industry.
Photos: Contact AMCS head office on (07) 3393 5811. Photo attached ‘Turtle Strike’ courtesy Lee Shipley, Bay Journal