False killer whales Archives

Hawaii false killer whales could go extinct by midcentury

August 18, 2025 — A unique species of endangered Pacific dolphin off Hawaii are declining at a faster rate than once thought, with the largest distinct population segment expected to drop below 100 individuals by the mid-2030s, according to new NOAA research.

Scientists from NOAA’s Pacific Islands Fisheries Science Center and other institutions found that between 1999 and 2022, the population of protected dolphins — known as “false killer whales” — shrunk by 3.5 percent annually. That trajectory places the species on a likely path to extinction by midcentury.

Roughly 132 individuals are believed to have lived in the population segment closest to Hawaii’s main islands in 2022, compared to as many as 190 in 2015.

Read the full article at E&E News

The Endangered Population of False Killer Whales in the Main Hawaiian Islands is Declining

August 15, 2025 — Three false killer whale populations occur in the waters of Hawaiʻi. There are two island-associated populations—one around the main Hawaiian islands and another around the Northwestern Hawaiian Islands—and a broadly ranging pelagic population. The small main Hawaiian Islands insular distinct population segment of false killer whales was listed as endangered in 2012 and faces multiple ongoing threats. Evidence suggests—based on high rates of dorsal fin and mouthline injuries—that fisheries interactions represent one of the most significant threats to this population. This threat may also act synergistically with other threats, such as exposure to pollutants and reduced genetic diversity, on the insular population. Scientists at the Pacific Islands Fisheries Science Center led the development of a new method to more accurately estimate the size of the main Hawaiian Islands insular false killer whale population by incorporating animal movement.

We analyzed photos of dorsal fins of 202 main Hawaiian Islands insular false killer whales encountered over 20 years (1999–2022) and movements from 53 satellite tags deployed from 2007–2022. We found that the population numbered 139 whales in 2022 and declined by 3.5 percent per year during the last 10 years of the study. Our findings provide the first reliable trend estimate for the population since it was listed as endangered and suggest the population will number fewer than 100 individuals within 10 years.

Read the full article at NOAA Fisheries

Report: Hawaiʻi’s False Killer Whales Trending Toward Extinction

August 14, 2025 — Thirteen years ago, the Main Hawaiian Islands’ dwindling population of false killer whales was officially declared endangered, a move intended to help their numbers recover after years of getting hooked and tangled in nets, mostly set by nearshore commercial fishers.

But instead of rebounding, a new report finds, the vulnerable group has only continued to shrink at a troubling pace.

The report, published Thursday in the journal Endangered Species Research, estimates that the unique population of false killer whales inhabiting the waters around the main islands has shrunk from about 184 individuals in 2012, when it was listed under the Endangered Species Act, to 139 members in 2022.

That’s an average population loss of 3.5% a year at a time when federal and state fisheries managers were supposed to be taking meaningful steps to better protect the mammals and boost their numbers.

Read the full article at Civil Beats

Fishing Gear Threatens Hawaiʻiʻs Already Endangered False Killer Whales

December 12, 2024 — A concerningly high number of endangered false killer whales are being injured when they get hooked by fishing gear in waters off the main Hawaiian islands, according to a new research paper released Thursday.

Published in the scientific journal Endangered Species Research, the research concludes there should be closer monitoring of that unique but dwindling local population and how the creatures — actually dolphins, not whales, and not killers — interact with the small-scale commercial and recreational boats that fish in those waters.

That could include installing cameras to record encounters with the false killer whales, which feed on the same large fish those boats catch and often go after what is already on the hook, said Robin Baird, a research biologist with the nonprofit Cascadia Research Collective, which led the study.

Read the full article at Civil Beats

WPFMC trying to tackle suite of issues, criticizes lack of NOAA support

April 8, 2022 — The Western Pacific Fishery Management Council (WPFMC) is trying to tackle multiple problems faced in its jurisdiction, including ineffective whale bycatch solutions, U.S. Endangered Species Act (ESA) consultations, creating more-equitable fisheries, and issues regarding fishery rights in American Samoa.

The council has been working to tackle how to handle false killer whale bycatch in the region’s tuna fisheries – mainly in Hawai’i and American Samoa. In 2013, a plan to use weaker circle hooks that are 4.5 millimeters or less in diameter was created. The weaker hooks were supposed straighten and release whales caught while still remaining strong enough to hook bigeye tuna and other marketable fish species.

Read the full story at SeafoodSource

Western Pacific Council Supports Protection of False Killer Whales, Leads US Fisheries Interests in Pacific

March 24, 2022 — The following was released by the Western Pacific Regional Fishery Management Council:

The Western Pacific Regional Fishery Management Council discussed today its position on the future direction for the False Killer Whale (FKW) Take Reduction Plan and agreed to not support adoption of weaker hooks under the Plan due to the potential economic impacts and lack of clear conservation benefit.

Fishermen are required to use 4.5 mm or less diameter circle hooks intended to straighten and release accidentally hooked FKWs, while retaining bigeye tuna and other fish species of market value. However, this weak hook has not been successful, with only approximately 10% of the interactions resulting in the hook straightening since the Plan’s implementation in 2013. A 2021 study showed that the weight and value of bigeye tuna may be reduced if even weaker hooks are required in the fishery.

“Weak hooks are not the best way to reduce the false killer whale interactions with the Hawai‘i fleet,” emphasized Roger Dang, Council vice chair for Hawai‘i. “Considering the prices of fuel and bait are up, any economic impacts from using weaker hooks would increase the difficulties in operating under these conditions. We need to focus our limited resources on what we believe will have the greatest impact.”

Council member McGrew Rice pointed out that a weak circle hook will not straighten if the hook is caught in the corner of the animal’s mouth. “The key is to cut the line close to the hook. A hook in a mouth will not kill a fish.”

The Council said the Plan’s priority should be to develop strategies to reduce trailing gear and find solutions to reduce depredation based on the latest FKW abundance estimates and other factors. The Council’s position was also based on input from its advisory groups.

The Hawai‘i deep-set longline fishery interacts with the pelagic population of FKWs, estimated to be approximately 25,000 in the central Pacific around Hawai‘i, with 2,100 individuals estimated to occur inside the three to 200-mile exclusive economic zone around the State.

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Council members expressed frustration at the continued delay of the Endangered Species Act consultations for the Hawai‘i deep-set longline (DSLL), American Samoa longline (ASLL), and Hawai‘i and territory bottomfish fisheries. Completion dates have been shifting with every Council meeting report for the last two years. Michael Tosatto, National Marine Fisheries Service (NMFS) regional administrator for the Pacific Islands, reported that the current dates presented at the meeting (April to May 2022) are unlikely to be met. Apparently reported that the current dates presented at the meeting (April to May 2022) are unlikely to be met. Apparently internal and external review steps are required. The Council asked NMFS to provide a timeline for Council’s draft review to assist with planning for advisory body meeting schedules.

Call for US Government to Work Better with Pacific Island Nations

The Council, with representatives from U.S. tuna industries, developed a paper that calls for a task force of federal agencies to work together to implement a new Pacific strategy. The paper’s holistic approach addresses greater U.S. trade and national security interests and how they are tied to the prosperity of U.S. tuna fisheries in the Pacific.

The Council endorsed the new Pacific strategy and recommended the U.S. delegations to the WCPFC coordinate with longline and purse seine fishing industries to implement it. Coordination efforts should lead toward an increase in the Hawai‘i longline fishery’s bigeye tuna quota and enhance opportunities for the American Samoa longline and purse seine fisheries. The U.S. government should ensure U.S. Pacific Island Territories take an active role in developing and implementing these objectives.

In American Samoa, Starkist cannery is the largest private employer. Will Sword, Council vice chair for American Samoa, noted the Council’s Pacific strategy is just what is needed. “It’s imperative to get the U.S. government and state and territory governments working closely with other Pacific Islands to implement a strategy that meets our goals,” said Sword.

“The current playing field is not level for American Samoa because our purse seine fleet is not seeing the benefits that we deserve as a territory” added Archie Soliai, Council chair from American Samoa. “The United States should take seriously the needs of its territories and this plan will help to move this forward.”

The Council recommended a letter be sent to the State Department and NOAA expressing concerns regarding the lack of acknowledgement of American Samoa’s rights afforded to small island developing States (SIDS) in the WCPFC. Under Articles 30 and 43 of the WCPFC Convention, SIDS and Territories receive certain benefits recognizing their aspirations and sovereign rights to manage their own fisheries. They are entitled to special provisions to prevent “disproportionate burdens” from conservation action.

The Council also recommended a letter be sent to the Biden Administration in response to its request for comment on development of its Indo-Pacific Strategy. The letter should reinforce the importance of fisheries to the Pacific Islands and the uniqueness of the Pacific Islands to the Indo-Pacific.

The Council meeting concludes tomorrow with discussions on American Samoa bottomfish and aquaculture management, and equity and environmental justice efforts, among other topics. Instructions on connecting to Webex, agendas and briefing documents are posted at www.wpcouncil.org/meetings-calendars.

Scientists Say NMFS Study Determined to be Inconclusive in Western Pacific Longline Fishery

March 18, 2022 — Sorry, Charlie: Weak hooks in the Hawai’i deep-set longline fishery for bigeye tuna won’t reduce impacts to false killer whales, scientists said when they met virtually this week.

The Western Pacific Regional Fishery Management Council’s Scientific and Statistical Committee found that a National Marine Fisheries Service 2021 “weak hook” study was inconclusive. Further, it did not provide scientific support for adopting weaker hooks as the primary strategy for reducing impacts to false killer whales, the WPRFMC said in a press release.

The study investigated the economic impacts of existing weak (4.5 mm diameter) and comparatively weaker (4.2 mm) hooks on target catch, primarily bigeye tuna. The study results showed the weight and value of bigeye tuna was higher for those caught on existing hooks than the weaker hooks.

Read the full story at Seafood News

Hawaii’s longline community scrambles to outfish false killer whales

March 16, 2022 — Those at the forefront of managing Hawaii’s deep-sea fishing industry are meeting this week in hopes of figuring out how to deal with their catch being seized off their lines.

It’s one of the issues facing the Western Pacific Regional Fishery Management Council, which oversees Hawaii’s longline vessels that bring in the ahi supply for the state and parts of the U.S. mainland.

Over the last several years, the council says its seen more cases of false killer whales, actually a species of dolphin, snatching fish right off a hook.

In years’ past, they’ve run into similar issues with seabirds and turtles, but gear has since been adapted.

Read the full story at Hawaii News Now

Western Pacific Scientists Found “Weak Hook” Study Inconclusive as a False Killer Whale Mitigation Strategy

March 16, 2022 — The following was released by the Western Pacific Regional Fishery Management Council:

The Scientific and Statistical Committee (SSC) found that a National Marine Fisheries Service 2021 “weak hook” study was inconclusive and did not provide scientific support for adopting weaker hooks as the primary strategy for reducing impacts to false killer whales (FKWs) in the Hawai‘i deep-set longline fishery. The study investigated the economic impacts of existing weak (4.5 mm diameter) and comparatively weaker (4.2 mm) hooks on target catch, primarily bigeye tuna. The study results showed the weight and value of bigeye tuna was higher for those caught on existing hooks than the weaker hooks.

The SSC noted that the weak hook approach is a flawed strategy that has been ineffective, highly stressful to FKWs and dangerous for fishermen as it necessitates creating tension on the line to attempt hook straightening. FKWs may become hooked on longline fishing gear because the whales feed on bait and fish caught on the line. Interactions between the Hawai‘i deep-set longline fishery and FKWs are rare—on average less than 10 are observed hooked or entangled each year.

SSC members reiterated their previous position that a better strategy would be to cut the line as close to the hook as possible so that the animal can be released quickly with minimal trailing gear that may cause further injury. “Gear release mechanisms that slide down the fishing line to cut near the hook are undergoing development and would be a better option than using weaker hooks,” said David Itano. “The fleet’s transition to monofilament nylon leaders is a game changer,” added Craig Severance. “It will allow fishermen to use simpler, less expensive line-cutting devices.”

Under the False Killer Whale Take Reduction Plan, fishermen are required to use 4.5 mm or less diameter wire hooks intended to straighten and release accidentally hooked FKWs, while retaining bigeye tuna and other fish species of market value. However, this weak hook has not been successful, with only approximately 10% of the interactions resulting in the hook straightening since the Plan’s implementation in 2013.

The SSC also heard a report on American Samoa Bottomfish Fisherman Data Workshops held in February 2022. SSC members emphasized that the information gleaned from these workshops would be helpful for the 2023 stock assessment.

The workshops highlighted several data issues, such as difficulties with distinguishing between similar species and gaps in data caused by lack of data collection, not lack in catches. Workshop participants included commercial and noncommercial fishermen, village leadership, and American Samoa Dept. of Marine and Wildlife Resources, Pacific Islands Fisheries Science Center and Council staffs. Fishermen provided both current and historical (1960s and ‘70s) bottomfish fishery insights that will help scientists to resolve discrepancies in the data for the 11 managed bottomfish species.

The SSC meeting continues tomorrow with discussions on 2021 Hawai‘i and American Samoa longline fishery status, area-based management and a new Pacific strategy for addressing international fishery management issues.

Pacific Fishery Scientists Recommend Ways to Better Manage False Killer Whale Impacts

September 20, 2021 — The following was released by the Western Pacific Regional Fishery Management Council:

The Scientific and Statistical Committee (SSC) of the Western Pacific Regional Fishery Management Council adopted recommendations to improve the management of impacts to false killer whales (FKWs) in the Hawai‘i deep-set longline fishery. The issues paper from an SSC working group reviewed cetacean avoidance research and interaction reduction measures, and risk assessment methods used to evaluate the population-level impacts of fishery interactions.

The paper, endorsed by the SSC, raises concerns about the serious lack of fundamental population demographic information needed to support evidence-based policy guidance on the issue. The current risk assessment framework used to evaluate the potential impacts of FKW bycatch in the U.S.-based pelagic longline fishery is based on a concept called the potential biological removal (PBR), which is required under the Marine Mammal Protection Act (MMPA). At its June 2021 meeting, the SSC acknowledged the PBR approach does not account explicitly for the present assumption that long-term consequences exist for FKW populations exposed to anthropogenic hazards such as pelagic longline gear. The working group found that available scientific data do not strongly support this assumption.

The SSC’s recommendations highlighted several approaches to address the current deficiencies in the risk assessments. This includes implementing a conceptual framework called “population consequences of disturbance” comprised of a four-level sequence, ranging from observed changes in individual behavior to population-level effects like impaired reproductive, survival or population growth rates. Another recommendation noted the need for a risk assessment model based on population dynamics to assess the applicability of PBR for bycatch management.

Also, the group recommended that a post-release study on FKWs should be conducted using satellite tags or other technology to assess mortality rates and sublethal effects of capture and release. Currently, there is not enough demographic information, such as survival rates at different ages and reproductive rates, to do a population assessment or diagnose trends for FKWs. Additionally, the lack of post-release survival data has led to the assumption that most FKWs observed in the Hawai‘i deep-set longline fishery are not likely to survive, even though most individuals are released alive.

“The underlying theme to all of these recommendations is that fishery impacts on FKWs to date have been seemingly small and infrequent,” said SSC Chair Jim Lynch, who presented the report. “Take reduction measures imposed should balance the biological and economic impacts.”

FKWs are incidentally hooked in the Hawai‘i deep-set longline fishery, which primarily targets bigeye tuna. Under the FKW Take Reduction Plan, fishermen are required to use hooks of a certain diameter intended to straighten and release the animals. However, this “weak hook” measure, among other requirements, has not been successful in achieving the conservation goals required under the MMPA. The Take Reduction Team, which includes members from academia, conservation groups, fishing industry, government and fishery management organizations, was not able to reach consensus on measures to revise the existing Plan after nearly three years of deliberations. In light of this situation, the SSC formed the working group to inform the future direction of this issue for the Council, which holds a seat on the Team.

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Regarding seabird conservation in the Hawai‘i longline fishery, the SSC recommended that tori lines should replace blue-dyed fish bait as a required bycatch mitigation measure. Scientists endorsed the findings from the tori line experimental fishing permit study that showed the streamers are significantly more effective than colored bait at reducing fishery interactions with seabirds like Laysan and black-footed albatross.

The Hawai‘i Division of Aquatic Resources (HDAR) summarized data for the SSC from four reopened bottomfish restricted fishing areas, or BRFAs. Data quality and quantity were concerns, creating challenges to interpreting effort and landings in evaluating the effects of BRFA opening. The SSC reiterated its recommendation since 2013 to eliminate all BRFAs in federal waters, due to the change in stock status since their establishment and because their management utility has been superseded by annual catch limits. The SSC also recommends HDAR continue to improve fishery-dependent data collection through better fisher engagement to effectively manage the bottomfish fishery.

Recommendations made by the SSC on these and other matters will be considered by the Council when it meets Sept. 21-23, 2021, virtually with host sites at Tedi of Samoa Building, Suite 208B, Fagatogo Village, American Samoa; BRI Building, Suite 205, Kopa Di Oru St., Garapan, Saipan, Commonwealth of the Northern Mariana Islands (CNMI); and Cliff Pointe, 304 W. O’Brien Dr., Hagatña, Guam.

Instructions on connecting to the web conference, agendas and briefing documents are posted at www.wpcouncil.org/meetings-calendars. Host sites are subject to local and federal safety and health guidelines regarding COVID-19; check the Council website for updates.