Shifting Baselines

In the recent issue of the journal Biological Invasions, my colleague Chris Wilcox and I published an essay entitled, Integrating invasive mammal eradications and biodiversity offsets for fisheries bycatch: conservation opportunities and challenges for seabirds and sea turtles. It expands on a previous paper we wrote in 2007 that makes an argument for biodiversity offsets in the fishing sector. The idea has turned out to be controversial to say the least, but that is not unexpected - new ideas are often so, and biodiversity offsets in general have been controversial in nature.

Here is how they would work with respect to fisheries bycatch. Globally, fisheries provide over a tenth of all protein consumed by humans, employ hundreds of millions of people, and are valued at around US$80 billion. Yet, at least a quarter of the global catch is non-target species and discarded. That mortality is having major impacts on species and ecosystems. For many fisheries, much of that discarded bycatch is endangered seabirds and sea turtles--species that spend part of their life breeding on islands and coastal beaches. At those breeding sites, seabirds and sea turtles commonly face additional anthropogenic mortality impacts, such as coastal development, direct human take, and impacts from invasive predators. Indeed most seabirds and sea turtles that are threatened by fisheries interactions are concurrently threatened by additional anthropogenic threats.

Fisheries are increasingly under national and international pressures to operate more responsibly. And some are doing so. Direct measures, such as changes in gear and fishing practices, has reduced sea turtle and seabird bycatch in some fisheries. But even the most responsible fishing fleets still kill a number of seabirds and sea turtles during operations - is it a cost of doing business. Those seabirds and sea turtles belong to you and me - to society. And we argue that fishers should re-pay those species to society.

Our proposal is based on a sustainable-use hierarchy of avoid, mitigate, offset. First, fishermen must avoid bycatch to an extent that is reasonable (e.g., don't fish in bycatch hotspots). Second, they must mitigate to reduce bycatch, such as implementing best practices in terms of fishing gear. Then, fishers should offset their residual bycatch (and perhaps get credit for doing so). They could do so by funding measurable conservation actions elsewhere that would "make" seabirds and sea turtles. Such actions could include the eradication of invasive predators, such as rats, from breeding islands, or measurable bycatch reduction programs in small-scale, unregulated fisheries that also have high bycatch rates of the same species.

Encouraging fisheries to offset bycatch that cannot be mitigated directly (either by avoidance or modifying fishing practices) by funding conservation interventions targeted toward other mortality threats could result in net conservation gains for seabirds and sea turtles. Contrary to others, we do not believe the fishing sector is responsible for the recovery of endangered seabirds and sea turtles- that is a job for society as a whole. We do believe, however, that fishers should be bycatch neutral, first avoiding and mitigating their impacts of fishing, and then offsetting the seabirds and sea turtles they kill as a part of doing business. This approach also has a number of advantages in that in helps aligns the incentives for fishermen to avoid catching seabirds and sea turtles in the first place.

For those are interested, the essay will be availble open access at Biological Invasions in the next few days. The abstract is pasted below. For more information visit www.advancedconservation.org

The removal of invasive mammals from islands is one of society's most powerful tools for preventing extinctions and restoring ecosystems. Given the demonstrable high conservation impact and return on investment of eradications, new networks are needed to fully leverage invasive mammal eradications programs for biodiversity conservation at-large. There have been over 800 invasive mammal eradications from islands, and emerging innovations in technology and techniques suggest that island area will soon no longer be the limiting factor for removing invasive mammals from islands. Rather, securing the necessary social and economic capital will be one main challenge as practitioners target larger and more biologically complex islands. With a new alliance between conservation practitioners and the fisheries sector, biodiversity offsets may be a promising source of capital. A suite of incentives exists for fisheries, NGOs, and governments to embrace a framework that includes fishery bycatch offsets for seabirds and sea turtles. A bycatch management framework based on the hierarchy of "avoid, minimize, and offset" from the Convention on Biological Diversity would result in cost-effective conservation gains for many threatened seabirds and sea turtles affected by fisheries. Those involved with island conservation and fisheries management are presented with unprecedented opportunities and challenges to operationalize a scheme that will allow for the verifiable offset of fisheries impacts to seabirds and sea turtles, which would likely result in unparalleled marine conservation gains and novel cross-sector alliances.