At the virtual meeting last month of the False Killer Whale Take Reduction Team (TRT), it became clear, early on, that agreement on substantive recom- mendations the group is tasked with making to the National Marine Fisheries Service (NMFS) would be difficult, if not impossible.
“Lots of things have changed since the TRT was formed,” noted Ryan Steen, an attorney and a member of the team representing the interests of the Hawai‘i longline fishery,
A new abundance estimate from NMFS for the pelagic population “changes the fishery’s view on this process and calls into question all the time, effort, and money spent on [it] since 2009,” he said.
That year, NMFS was petitioned to list the insular population of false killer whales as endangered, given new and startling research suggesting a dramatic decline in that population corresponding to the rise over the previous two decades in the Hawai‘i-based longline fishery.
In 2010, under the Marine Mammal Protection Act, NMFS established a Take Reduction Team to examine potential ways of mitigating the bycatch of the animals and rebuilding both the pelagic and insular populations, and to make recommendations to the agency, which will inform its Take Reduction Plan, adopted as a rule. Among other things, the plan, adopted in late 2012, calls for the reduction, within six months of its implementation, the number of animals harmed to less than the so-called potential biological removal (PBR) – the number of animals that can be taken out of the population as a result of human activity while still allowing the population to reach or maintain its optimal level. Within five years, bycatch levels should approach zero or, at least, fall below 10 percent of the PBR.
To facilitate the removal of gear from animals that are hooked, the fishery was to employ weaker hooks, allowing them to be straightened when tension is applied, and stronger branch lines, which would resist breaking and possibly entangling the whale. Training of captains and crew is also an important part of the plan.
Finally, if the longliners kill or seriously injure two false killer whales within the EEZ in a calendar year, the waters in some112,000 square miles of the EEZ south of the islands – an area known as the Southern Exclusion Zone (SEZ) – are placed off-limits to the fishery. In July 2018, the SEZ was closed and it remained closed until the end of that calendar year. Just two months later, with two FKW hooked inside the EEZ and determined to meet the mortality/serious injury criteria (M&SI), the SEZ was closed again and remained closed until August of this year.
For the last couple of years, the longlin- ers were anticipating NMFS’s release of the updated population estimate for the pelagic (open-ocean) stock, expecting that this would result in relaxed limits on the fishery and even allow the threat of the SEZ closure to be eliminated.
In fact, Michael Tosatto himself, administrator of NMFS’s Pacific Islands Regional Office, suggested as much last spring. In comments to the Western
Pacific Fishery Management Council, Tosatto suggested that in the event the new population estimates increased the PBR for the insular population, NMFS might “sort of walk away from a TRT wholly.”
Those New Estimates
When NMFS finally unveiled its new abundance estimate, which informed the discussion at the TRT meeting in October, it put the pelagic stock at 2,086 individuals, with a PBR set at 16 animals per year within the EEZ. NMFS determined that the five-year average of M&SI for this pelagic stock was 9.8 per year.
The most recent abundance estimate for the insular stock was made in 2015, at which time the population was pegged at 167, with a PBR of 0.3 animals per year, or about one animal every 3.3 years. The average annual M&SI for this stock for the 2014-2018 period was 0.03, or 10 percent of the PBR losses that NMFS believes the stock can support.
But while the estimates of mortality and serious injury among both populations of false killer whales fall below PBR, other objectives of the take reduction plan are unmet.
The goal that incidental takes of false killer whales be reduced to “insignificant levels approaching zero” – functionally, less than 10 percent of PBR – was not met in the 2014-2018 time frame.
Also, the goal of no increase in the M&SI of the pelagic stock taken on the high seas (outside the EEZ) was not achieved. At the time the plan was implemented, the annual M&SI for this population was 11.2 animals. But for the 2015-2019 period, the actual number was 28.8 a year. (For that same stock inside the EEZ, there was still substantial estimated take. For 2019, a six-year high of 25 animals were thought to have been killed or seriously injured in interactions with the deep-set longline fishery.)
Soon after the new figures were presented to the take reduction team, Robin Baird of the Cascadia Research Collective noted that the mortality and serious injury estimates are almost certainly lower than the actual number of animals harmed. “There are a lot of unobserved fisheries,” said Baird, who has extensively studied false killer whales and other more cryptic whales and dolphin species in Hawai- ian waters. “For example, I know of depredation-type interactions occurring in unobserved fisheries, from photos and direct observations people have reported to me. The insular stock is interacting with other unobserved fisheries.” (Depredation occurs when non-target animals, such as whales, attempt to take caught fish while lines are still in the water.)
“This is just one fishery, albeit the largest one,” Baird said, referring to the longliners. “The question is, how is mortality and serious injury occurring in other fisheries? … The PBR for the insular stock is so small, and so many other fisheries interact with the insular stock, it wouldn’t take much to increase to the level PBR is reached.”
Everyone on the TRT agreed that reducing interactions was the overarching goal. There was little agreement on how to achieve that.
In the past, gear changes had been viewed as a means of mitigating harm to hooked false killer whales. As Brendan Cummings of the Center for Biological Diversity noted, the idea was that stronger branch lines and weaker hooks were required to be deployed on longline vessels. “The premise is this would straighten the hooks,” which, with the stronger branch lines, would allow the hooks to be pulled out with no break in the line. “What we’ve seen in the years since, approximately 80 percent of the time it doesn’t work. The branch lines break, or even if it doesn’t break, the hook doesn’t straighten. We need weaker hooks and stronger branch lines,” he said.
Cummings then suggested more experimenting with the new gear types. “If it works, we adopt it,” he said. “To the degree there’s an exchange in building consensus to get the fleet to accept that, the SEZ could be phased out and there could be a strong emphasis on electronic monitoring.”
Steen, however, rejected that. “Asking the fleet to change over all hooks isn’t acceptable. The SEZ has no place in the plananymore and should be removed.”
One possible area of agreement identified by Steen was in the area of reducing depredation. “That was a big piece of the discussion early on in the TRT,” he said. “If we are going to be shifting focus, the fishery would like to pick that up again. Reducing depredation has the dual benefit of the fleet catching more fish and of keeping whales away from the gear.”
Dennis Heinemann, representing the Marine Mammal Commission on the team, agreed that the plan was not working well. “The bycatch rate in 2016 was way above the new PBR,” he noted. What’s more, the goal of reducing take to below PBR in the pelagic stock was achieved only because “we have a new estimate of population size,” which increased PBR.
“The trend for the last decade has been a strong and large increase in the number of hooks set per year. Given that there hasn’t been a change in bycatch per unit [catch per thousand hooks set], that means we’re just going to be catching more and more false killer whales. In the future, M&SI is likely to be back up to where PBR is.”
Fisherman John LaGrange said that the plan was doomed to fail. “The fishery in general thought population estimates were unrealistically low, which has proven to be true. Fishermen universally think the criteria for determining [mortality and serious injury are unrealistic….
“In fisheries population dynamics 101, if your effort is increasing and [catch per unit effort] is also increasing, that means the population is increasing,” he said.
LaGrange then referred to the classification of the deep-set longline fishery as a Category I fishery by NMFS, which ranks fisheries according to the level of interactions with marine mammals that result in serious injury or death.
“The standard is supposed to be, if it’s a rare event, it’s category II or III. The point zero three [0.03 animals per year] is one animal every thirty years. If you divide that over the fleet, that’d mean one boat would catch an animal every 3,300 years, and if that’s not a rare event, I don’t know what is.”
Heinemann suggested that the team look to what’s being done in New England to reduce whale entanglements. There, a “risk-reduction model calculates risk reduction associated with different measures,” he said. “Some are gear, or closures, or some have to do with differ- ent gear aspects.
“What they’ve realized there is the same thing we realize here. There is no silver bullet, no single silver bullet. The solution here may be like what they’re trying to achieve in New England. Get 10 percent of MSI reduction from this measure, something else from that measure. And then you have an effective plan. We need to look at a broader range than just weak hooks and stronger branch lines. It might require a suite of measures that get you to all the goals of the Marine Mammal Protection Act.”
In the end, the team was able to agree on recommendations to NMFS that involved further research on avoiding depredation, additional training of crews, and meta-analysis of data.
Ann Garrett, the assistant regional administrator of NMFS’s Protected Species Division, told the team that she was disappointed with the lack of agreement on more meaningful recommendations. “The plan isn’t working,” she told team members. “I appreciate the recommendation for more studies, but we’re looking at two years, probably three, before we get to a reduction of MSIs. But thank you all for your continued work on this problem.”
— Patricia Tummons