ACS Directors Chris Wilcox and Josh Donlan publish a new paper "Compensatory mitigation as a solution to fisheries bycatch-biodiversity conservation conflicts" in the upcoming August 2007 issue in the journal Frontiers in Ecology and Environment outlining new thinking on the management of seabird and sea turtle bycatch.
See summary below and click here for more information.
Click here for a copy of the paper.
Also click here for a Podcast with an interview with Chris Wilcox.
Removing invasive predators from island breeding colonies could save more seabirds for less cost than reductions in fishing, a study of Australia’s Eastern Tuna and Billfish Fishery (ETBF) has found.“A major challenge for fisheries worldwide is to reduce their impact on non-target or ‘bycatch’ species such as seabirds,” Dr Chris Wilcox of CSIRO says.“Methods of reducing bycatch include modifying fishing gear and restricting areas and periods of fishing, but these measures are not always effective, leading to costly interventions such as fishery closure.”“While the priority should always be for fishers to avoid bycatch, they could also ‘offset’ bycatch that does occur by funding conservation measures that tackle other, often greater, threats to bycatch species.”Dr Wilcox and C. Josh Donlan of Cornell University explored the offset approach in a study of flesh-footed shearwater bycatch in the ETBF, which catches yellowfin and bigeye tuna, albacore and billfish.Practices used in the ETBF to reduce the capture of seabirds on longlines are costly and not always effective for all species. A species of concern is the flesh-footed shearwater, which in eastern Australia breeds only on Lord Howe Island where rats are potentially a major predator.Wilcox and Donlan compared the impact of fishing with that of rat predation on Lord Howe Island flesh-footed shearwater populations, and the costs and benefits of rat control and fishery closures.They found that banning fishing in a 750-kilometre radius of the island would result in a 6% increase in growth rate of the shearwater population, at a cost of about US$3 million. The eradication of rats would result in a 32% increase in the population growth rate, at a cost of about US$500,000.Rat eradication therefore could yield a conservation return on investment 23 times greater than a fishery closure, and could have broader ecosystem benefits.“Vessel levies could be set at the cost of offsetting their bycatch,” Dr Wilcox says. “As well as funding actions that effectively offset the bycatch that does occur, the levy would encourage fishers to seek innovative ways of avoiding bycatch.”Dr Wilcox says the environmental community has made great strides in drawing attention to fisheries bycatch. Fishers, technologists and scientists in turn have reduced bycatch substantially through fishing-method innovation.“For fisheries to have a zero impact on bycatch, however, they will need to use the full suite of cost-effective tools available, in a responsible and integrated way,”he says. Wilcox and Donlan believe that given the number of seabirds and other mammals affected by fisheries and invasive species, the offset approach could prove effective in many scenarios worldwide.