Orca recovery goes high pitch
Updated: Jan 1, 2019
If you're unaware of Southern Resident Orca's plight, and the recent discussions around how to reverse their declines you've probably been asleep for a decade. This summer the world's attention was rapt as Orca mother J35 pushed her dead calf for 17 consecutive days in an apparent act of mourning. The story drew national attention in both the US and Canada to the ongoing decline of southern resident J-pod which hasn't had a calf survive infancy in three years, sparking calls for immediate action from governments and a region wide scramble to come up with solutions.
The primary reason for the decline of Orcas in the Salish Sea has been a collapse of Chinook salmon populations. Chinook are the primary prey of southern resident Orcas, and in the last few years we'veseen record low returns of Chinook to the rivers around the Salish Sea. While salmon runs undoubtedly fluctuate up and down, the trend has been going in the wrong direction for almost a 50 years, and today Chinook in Puget Sound are listed under the Endangered Species Act. So too are Chinook in the Snake and Columbia Rivers which likely make substantial contributions to Orca diets. Advocates have rightly said that breaching the four lower Snake River dams is one of the most impactful actions we can take to restore salmon and Orcas. Not surprisingly, despite public support for breaching the government has dragged its feet in even considering dam removal among the suite of restoration actions.
With J35 publically shaming us this summer for our inaction, alarm bells began ringing about the fate of Orcas and their favored prey. Conservation groups responded with calls for immediate closures of Chinook fisheries, while hatchery-loving state managers saw the crisis as an opportunity to direct more tax dollars towards their favorite sacred cow, hatchery supplementation. The problem is there isn't a ton of evidence that hatcheries even work to increase abundance of Chinook in the Salish Sea, and the programs are so ineffective that every Chinook harvested in the fishery costs Washington taxpayers over $700. Fisheries closures probably hold more promise, and DFO acted quickly, closing large portions of the Strait of Juan de Fuca, Gulf Islands as well as the mouth of the Fraser River to fishing to protect salmon in critical Orca feeding areas. WDFW has also experimented with seasonal or voluntary closures, although to a much lesser extent. These efforts were panned by conservation groups as inadequate, particularly after the Canadian government declined to issue an emergency order to protect Orcas using the Species at Risk Act. Here's a statement from a group of conservation minded NGOs in British Columbia.
We've also heard some very shrill and misguided discourse in the media about people who are no longer eating salmon to "help the Orcas", despite the fact that the VAST majority of commercially caught salmon in BC and the Western US does NOT come from the Salish Sea. If you want to help you'd be better off reducing your carbon footprint, donating money to an NGO that does habitat restoration or stormwater mitigation, or doing really anything other than stopping eating salmon that aren't even caught in the Salish Sea.
Fishing closures do represent a valuable first step for Orca recovery, but on their own will be inadequate to restore Chinook. We know for instance, that the proportion of Chinook taken by fisheries has been declining in recent decades. Far more chinook are eaten today by Northern Resident Orcas and pinnipeds, particularly Harbour Seals than are taken in fisheries. Fisheries closures are likely a good idea, if only to allow whales to forage unmolested by noise and angler traffic, but on their own they wont accomplish salmon or Orca recovery. There's also a strong case to be made that keeping some of fishing opportunity and access to salmon for people in the Salish Sea region is a critical tool for maintaining a constituency of people who care about salmon and the ocean.
One thing that I've NEVER understood though are winter Chinook fisheries, or "blackmouth" as they're called in the US. These fisheries intentionally target and harvest juvenile Chinook residing in the Salish Sea. We know that Orcas preferentially select larger salmon, and killing Chinook that are growing and feeding in the Salish Sea reduces the likelihood that they'll ever get large enough to be eaten by an endangered Orca. The other problem is that Canadian hatcheries do not routinely clip the fish they release, reducing the possibility of mark-selective fisheries. As such, sport fisheries currently hammer chinook in the Salish Sea, with fishing open 7 months of the year in WA. In BC, fishing is open year round in many marine areas, with retention of unmarked (e.g. wild) chinook allowed. While the sport fishing lobby would undoubtedly kick and scream, closing winter chinook fisheries as a way of allowing more fish to mature to spawning age, enter the Orca prey size window, and ultimately return to spawn could be a valuable measure. Particularly if fishing opportunities remained in place from June -September.
While climate change and habitat degradation have certainly played a role in depressing Chinook populations in the Salish Sea, an explosion in the abundance of Harbour Seals is also likely part of the story. Since the 1970s when seals and other marine mammals received legal protection in Canada and the US, the number of Harbour Seals in the Salish Sea has skyrocketed from under 5,000 animals to nearly 100,000. Over the same period smolt-to-adult survival for salmonid species with large bodied smolts (eg. chinook, coho, steelhead) has tanked in the Salish Sea. While correlation doesn't necessarily imply causation, diet data and the known bioenergetic requirements of Harbour Seals has produced some pretty astronomical estimates for the number of juvenile chinook eaten annually by our now VERY healthy seal population. Despite this reality, many conservation NGOs have deflected blame from seals and suggested they're being scapegoated for salmon declines. The idea that predation by a native species could be part of the problem taps into a reflexive ideological need to point fingers at people for damaging the ecosystem (often justly), but puts possible solutions out of reach. People seem forget that humans hunted and managed seals for millennia before colonization, and that the ecosystem conditions we consider "pristine" reflect the legacy of thousands of years of hunting. As it currently stands we may be replacing ESA listed Orcas with hyper-abundant Harbour Seals, while having far fewer salmon and steelhead for everyone, not a particularly desirable outcome.
So in summary, this issue is incredibly complex. There is no one quick fix. But here's some recommendations. Take them as one scientists personal opinion:
1.) Remove Snake River dams - this is obvious. Undaming the lower Snake River would improve passage conditions for Chinook and create hundreds of miles of new mainstem habitat, a boon to ESA listed salmon of all species and the Orcas that depend on them.
2.) Enact spatial and temporal restrictions on vessel traffic and whale watching to reduce harassment and noise pollution impacts.
3.) Maintain current network of spatial fishing closures in BC and expand them in Washington.
4.) Clip hatchery Chinook in BC waters to allow mark-selective fisheries
5.) Reduce winter fisheries, particularly in BC waters where wild Chinook are currently retained as subadults.
6.) Restore habitat, particularly lower rivers, estuaries and floodplains where Chinook rear and thrive. See the Nisqually estuary restoration for a powerful example
7.) Consider experimental seal hunts to reduce predation on subadult Chinook and other salmon. This is likely a heavy lift in our society, and understandably elicits strong reactions from people opposed to it. While I would definitely not promote wholesale culling of seals, reducing seal abundance experimentally in some areas could provide powerful insight into the degree to which seals are currently hindering salmon recovery. We're fortunate that we have fjords and semi-isolated water bodies where we could conduct and monitor the outcome of these experiments (e.g. Hood Canal, Howe Sound, Cowichan Bay). Adaptive management requires experiments, and we know that the system isn't working right now.
All told this is a powerful issue which inspires passion among PNW residents like few others. Ultimately, if we are going to save Orcas we need all hands on deck and all options on the table. Time is running out, but to a large degree we know what it will take to recover Orcas and their favorite food. The question is, are we willing to make the changes necessary to make that happen??