There are troubling signs for the survival of the critically endangered scalloped hammerhead shark in Queensland.
The latest fisheries data comparing 2019 with 2018 suggests the numbers of scalloped hammerheads are continuing to fall, with commercial gillnet fishers reporting fewer catches of the shark.
The number of scalloped hammerheads caught across Queensland’s commercial gillnet fisheries dropped from 8,084 to 4,532 individuals, equating to a 15% decline in catch rate per fishing day across all of Queensland waters. In the World Heritage-listed Great Barrier Reef Marine Park, the number of scalloped hammerheads caught fell from 3,360 to 991 individuals during the same period.
In December 2019, the global status of scalloped hammerheads was escalated from endangered to critically endangered by the International Union for the Conservation of Nature’s (IUCN) Red List. The IUCN’s recommendation is for the fishing of scalloped hammerheads to stop across the entire world.
Queensland’s east coast gillnet fishery spans the entirety of the Great Barrier Reef and continues to profit off the fins and flesh of the critically endangered scalloped hammerhead.
Dr Leonardo Guida, shark scientist at the Australian Marine Conservation Society (AMCS) said: “The latest fisheries data on this species is a cause for concern. It seems to indicate that critically endangered scalloped hammerheads are being driven closer to extinction in Queensland waters, and the situation is worsening each year.
“On any given day, it looks like the chance of fishers encountering a scalloped hammerhead have declined.
“What continues to worry us is that Queensland still lacks independent observation of its fishing activities. The numbers we’re seeing here are conservative, and since 2012 there’s widely acknowledged concerns about under-reporting from fishers.
“Who knows the true extent of just how many scalloped hammerheads are dying in Queensland’s gillnet fisheries. Their iconic-shaped head means they get caught in gillnets really easily and start suffocating to death.”
Despite indications that critically endangered scalloped hammerheads are becoming harder to find in Queensland waters, of those caught in 2019, 982 were dumped most likely dead or dying. Studies show that only around 2 in 10 hammerheads caught are alive when they are thrown back, and those thrown back alive have a slim chance of survival.
Currently, a national effort is being directed by federal and state governments to provide the latest estimate of the number and distribution of scalloped hammerheads in Australian waters. The findings will be used to inform Australia’s peak independent scientific body, the Threatened Species Scientific Committee, in their upcoming review of the scalloped hammerhead’s threatened species status.
Lawrence Chlebeck, marine biologist with Humane Society International said: “How many warning signs do we need? An independent report revealed that Queensland is still failing to enact measures to adequately protect this critically endangered shark, and as a result it should be listed as such under our national laws.
“These sharks are apex predators and critical to our ocean’s health because they help keep food webs balanced. This is especially important for boosting the Great Barrier Reef’s resilience in the face of warming waters due to the climate crisis, and a myriad of other threats.”
Notes to editors
Scalloped hammerhead sharks can be commercially fished in the Great Barrier Reef for their fins and flesh. This is because their status under Australian law is ‘conservation dependent’, meaning they can be commercially exploited.
The catch rate is defined as a catch per unit of effort, in this case the effort being the number days in which scalloped hammerheads were caught by gillnets. The rate is therefore the total number of scalloped hammerheads caught divided by the number of days in the same year they were caught. For example, in 2018 there were a total of 1,005 fishing days where 8,084 scalloped hammerheads were caught in gillnets throughout Queensland, equating to 8.0 scalloped hammerheads per fishing day. In 2019, although the days spent fishing were fewer (660), only 4,532 scalloped hammerheads were caught equating to a reduced rate of 6.9 per day of fishing or a 15% reduction. In short, more effort had to be expended in 2019 to catch the same amount as in 2018.
The 2019 fisheries data is unavailable online and was obtained by request from Queensland’s Department of Fisheries. Data from 2018 is freely available online at https://qfish.fisheries.qld.
Estimates were derived from a conservative value of 4kg per retained shark and the number of discarded individual sharks reported by Queensland’s Department of Fisheries.
Media contact: Jo Manning 0405 567 228 / [email protected]