When it comes to marine mammals in the Pacific, there is no shortage of crises. Tour operations are rousing spinner dolphins from their rest, fishing gear is hooking and entangling whales, and young monk seals in the Northwestern Hawaiian Islands just aren’t making it to adulthood. But as speaker after speaker at last month’s three-day Marine Mammal Commission meeting in Waikiki showed, resource managers, scientists, and NGOs are chipping away at the mountain of work that needs to be done to protect some of the Pacific’s most charismatic marine life.
Commission chair John Reynolds concluded the meeting by saying that he felt confident that the marine mammal research and management community knows what needs to be done and that there is momentum toward attaining the interagency cooperation needed to improve the status of marine mammals in Hawaiian waters. Reynolds also suggested that it was likely the commission could provide funds for the creation of a white paper on monk seal recovery as well as a workshop for the various agencies and groups with a stake in the seals’ survival.
With regard to the other marine mammals in the Pacific region, the commission mainly offered advice on how agencies can best make use of limited resources. The following is a sample of some of the research presented and discussion that took place.
A Shifting Paradigm
The remote, largely uninhabited Northwestern Hawaiian Islands (NWHI) have long been where most Hawaiian monk seals (Monachus schauinslandi) lived, but in recent years, an increasing number of seals have been spotted and are being born in the Main Hawaiian Islands (MHI), which is also home to nearly 1.3 million people. What’s more, the seals in the MHI seem to be healthier and more apt to survive to adulthood. In 2009, researchers identified 113 monk seals in the MHI (up from 88 in 2008) and there were 21 known births (up from 12 and 13 in 2006 and 2007, respectively).
Lloyd Lowry, a member of the endangered Hawaiian monk seal recovery team, told the commission that the MHI subpopulation may equal some of the larger populations in the northwest, and may, in fact, exceed them if all of the seals here are taken into account, including those at Ni`ihau, which researchers have not yet properly surveyed.
“We’re in the middle of a paradigm change in how we deal with recovery of the species,” Lowry said, noting that for the past several years, all seal recovery activities were directed towards the NWHI.
“There were some seals in the MHI, the ones Bill Gilmartin [a former NOAA monk seal expert] and others brought here…and females moving in, pups being born. But we basically viewed those as problems,” he said of the old days.
Population data collected over the years by the National Marine Fisheries Services’ Pacific Islands Fisheries Science Center, however, indicate that if the Northwestern and Main Hawaiian Island populations of endangered Hawaiian monk seals follow their current trends, in 20 years there will be fewer than 600 seals left in the wild, most will live in the MHI, and fewer than 200 will live in the NWHI.
According to PIFSC monk seal researcher Charles Littnan, the NWHI population is in a strong decline that is likely to continue with so many young among the dying, even if environmental conditions improve. Key to preventing a collapse, Littnan said, is building an appropriate age and sex structure for the population.
“We’re about to lose all of our females,” he warned the commission.
Faced with this population shift, presenters at the commission’s meeting discussed how efforts in the NWHI might change, as well as some of the issues managers will have to contend with as the MHI population grows. Already, the science center documented 12 monk seal hookings and four deaths last year, two of which were seals shot on Kaua`i – a male and a pregnant female – as they rested on the beach.
David Schofield of NMFS’ Pacific Islands Regional Office detailed the history of the handful of “problem seals” in the MHI that have been born on populated beaches, imprinted on people, and/or are being fed by them. He noted that in addition to relocating and recapturing these animals, resource managers have resorted to shaking palm fronds at them as a form of “aversive conditioning” and might even consider using rubber bullets.
According to Littnan, the PIFSC is developing a MHI research plan for monk seals that will include population surveys, foraging ecology studies, and research on their health and diet, among other things.
“We have really great baseline data, but we have an opportunity to do in the Main Hawaiian Islands something that we weren’t able to do in the Northwest and that’s really, starting from scratch, learning about the ecology of the animals down here…. It’s a daunting task and perhaps a little bit lofty, but I think it should be doable,” he said.
He added, “The whole gist of doing this is it’s great that we’re all thinking that the MHI population is a wonderful thing, but we need to make sure that we’re paying attention to where that’s going and what that might possibly do in the future. Right now we’re focused on animals disturbed on the beach or a dog that is after mom and pup pair, but this population could grow [and lead to] much more difficult problems to deal with, such as fisheries interactions and the like.”
The possibility that interactions in the MHI might limit the population’s growth was not lost on commissioner Douglas Wartzok, who urged the commission to not get too carried away with “one line on a graph that has a limited amount of data behind it.” He said that managers thought they knew what they were doing with seals several times in the past and that there are many potential problems – like fishery interactions – in the MHI.
With regard to protecting the NWHI population, Lowry said that things can probably be done to improve the ecosystem there, but they would be difficult to identify. Even so, he said that managers need to take actions to increase the odds that the NWHI ecosystem will favor monk seal survival. He added that the monk seal recovery team, which met earlier in the week, also believed that relocating seals may be necessary in the long run and suggested drafting a white paper, accompanied by a small workshop, to address the broad range of problems the seals face.
Commissioner David Laist suggested that the white paper should perhaps include an analysis of how and whether spiny lobster restoration in the NWHI might also help monk seals. The lobster population there used to be dominated by spiny lobsters, but, now, after years of overfishing, it is now dominated by slipper lobsters.
In the near-term, Littnan said, “interventions” such as captive care and translocation, among others, will be aimed at fortifying population age structures by increasing the number of female seals of different age classes.
“Although the ultimate goal is to increase abundance to meet recovery goals, in the interim, building healthy age structures that maximize the population’s reproductive value is an appropriate objective for designing the interventions… So it may not seem like we’re making a lot of changes, but it’s a critical first step,” he said.
In addition to propping up the female population, PIRO deputy administrator Mike Tosatto said his agency plans to continue its efforts to control or kill sharks that are preying on monk seal pups at French Frigate Shoals in the NWHI. The state Board of Land and Natural Resources has reluctantly granted permits to NMFS to kill or harass sharks attempting to feed on seal pups. Although the last permit was for non-lethal actions only, they were poor deterrents. As a result, NMFS will again seek permission to kill sharks.
“We all know that sharks will predate. They do it at places other than French Frigate Shoals, but we want to get French Frigate Shoals back to the level of what we’ll call ‘natural predation.’ What’s happening up there now is natural in a sense, but it’s different than every other island out there. We need to address it,” Tosatto said.
In July 2008, KAHEA: The Hawaiian-Environmental Alliance, The Center for Biological Diversity, and The Ocean Conservancy filed a petition with NMFS to revise the existing critical habitat designated for monk seals to include coastal and marine areas in the MHI, and to extend critical habitat in the NWHI to include important foraging grounds.
Littnan told the commission that after the petition was filed, his agency increased its efforts to geo-reference its historical data and is in the process of developing a GIS application to map the density and distribution of seal haul-outs to “try and get a handle on which areas are going to be more important for seals now and in the future.”
The NMFS plans to issue a proposed rule on critical habitat in 2010 and a final rule in 2011.
Saving the Sleeping Spinners
“I think this is a really sad situation,” Lowry said of the glacial pace at which the swim-with-dolphin tours at Kealakekua Bay are being dealt with.
Five years ago, when the commission met in Kona, the Board of Land and Natural Resources had just adopted a rule aimed at stamping out statewide swim-with-dolphin tours, which were not only proliferating, but were engaging dolphins when they would otherwise be resting. But because the Marine Mammal Protection Act prevents states from adopting their own rules relating to marine mammals, the state has been handcuffed in its efforts to control the tours.
Today, the tours continue unabated, and according to Marie Chapla Hill of the University of Hawai`i’s Joint Institute of Marine and Atmospheric Research, there is evidence that they are affecting the dolphins.
In Hawai`i, there are seven proposed stocks of spinner dolphins. They tend to forage along the 20 meter isobath and, on O`ahu, they rest between noon and 4 p.m. On the Big Island, they rest earlier, she said.
In 2004, Hill said, a study by Dr. Jan Ostman-Lind suggested that dolphin tours had caused a population of spinner dolphins to abandon their known resting site at Makako Bay on the Big Island’s west coast. Tours also interfere with a pod’s swimming patterns, she added, explaining that when a boat approaches a pod, the pod will split into two then reform after the boat passes.
Hill said that because approach rules are difficult to enforce, managers are considering establishing time/area closures in Hawai`i.
Although NMFS does plan to draft rules to deal with the issue, PIRO’s National Environmental Policy Act specialist Jayne Lefors told the commission that her agency is holding off on this effort until a more thorough population assessment of spinner dolphins is completed. Jim Lecky of NOAA’s Office of Protected Resources added that the extra research is being conducted to ensure that whatever rules the agency ultimately issues, they won’t be struck down later in a lawsuit for being arbitrary or capricious. Since the current information on spinner dolphins doesn’t meet that standard, proving that spinner dolphin populations are affected by these tours would help in any defense, he reasoned.
While he didn’t argue against collecting population data, the commission’s general counsel, Michael Gosliner, pointed out that under federal law, an agency doesn’t have to show that a population is being impacted before it adopts rules. All that needs to be proved is that individual animals are being affected, he said, adding that the evidence Hill presented suggests that this threshold has already been crossed.
“I don’t think the hurdle is as high as suggested,” he said.
According to Lefors, PIRO has no dedicated funding for spinner dolphins. Even so, she said NMFS plans to issue a draft environmental assessment on a proposed rule in 2011 and adopt a rule – most likely a time/area closure – the following summer.
But even if a rule to protect spinner dolphins goes through in a couple of years, she added, there may need to be a broader, overarching rule about marine mammal tours in general, since some tour operators have been known to seek out pilot whales when they can’t find spinner dolphins.
Hawaiian False Killer Whales
Last fall, the Natural Resources Defense Council filed a petition with NMFS to list Hawai`i’s insular stock of Hawaiian false killer whales (Pseudorca crassidens) as endangered and designate critical habitat for it. Last year, after successfully prodding NMFS to classify the Hawai`i longline fishery as a Category I fishery (one that frequently and incidentally kills or injures marine mammals), Hui Malama I Kohola, the Center for Biological Diversity, and Turtle Island Restoration Network filed a motion in U.S. District Court in Honolulu aimed at getting the agency to take the next step under the Marine Mammal Protection Act: namely, to develop a Take Reduction Plan and a Take Reduction Team for the whales. At the commission’s meeting, cetacean researchers and NMFS representatives addressed the status of the whales and the agency’s efforts to protect them.
According to Robin Baird of the Cascadia Research Collective in Washington state, Hawai`i’s false killer whale population is in dire straits. A 2006 population estimate of cetaceans around Hawai`i indicated that false killer whales were the least abundant species among the 18 that were surveyed.
Typically considered an ocean-going, or pelagic, species, the Hawai`i stock in 2008 was split into two by NMFS – an insular stock and a pelagic stock. Baird said the pelagic stock is composed of 484 individuals, while the insular stock numbers only 123. The stocks have an annual potential biological removal (PBR) of 2.4 and 0.8, respectively. (The PBR reflects the maximum number of animals, not including natural mortalities, that may be removed from a marine mammal stock while allowing that stock to become or remain sustainable.)
Not only is the insular stock tiny, it’s declining, Baird reported. In 1989, with a population of 470 individuals, the insular false killer whale was the third most-encountered cetacean in Hawai`i surveys, he said. Today, it’s the ninth most-encountered species.
What’s causing the decline? According to Baird, a number of things. He said that the whales, adult males in particular, have PCB levels that exceed the level where immune system function and reproduction begin to be affected. He also listed the different ways Hawai`i’s fisheries may be impacting the population as the whales feed primarily on the same large game fish that are targeted by Hawai`i’s fisheries.
There may just be fewer fish to eat, Baird suggested, citing data from the Western Pacific Fisheries Management Council that show there has been a drop in catch per unit effort for certain fish species, yellowfin tuna, for example. Baird also suggested that swallowed fish hooks and gunshots from angry fishermen may also be contributing to the whales’ decline.
Bycatch by longliners is yet another cause. Baird said that Hawai`i longline fishery has exceeded the PBR level for false killer whales every year since 2000. Over the past five years, the fishery has killed an average of four to nine false killer whales within the Hawai`i Exclusive Economic Zone. Between 1997 and 2007, the fishery killed or seriously injured 124 whales (a conservative estimate, according to Baird). In 2009, the stock experienced one of the highest levels of takes by the Hawai`i longline fishery, according to Erin Oleson, a cetacean expert with the PIFSC.
To better understand the extent to which fishing is affecting the insular population, Baird suggested that whale interactions with shortline and kaka line fisheries, which use techniques similar to longline fishing but drop shorter lines, need to be documented. Right now, neither fishery is managed by the federal government and, as a result, no observers have been required to document any interactions.
Oleson added that the PIFSC plans to work with the Hawai`i Longline Association to place acoustic recorders on longline gear to help determine when, exactly, whales are interacting with the lines. If the whales are taking fish while the line is being hauled rather than when it is soaking (which is what longliners suspect is happening), there may be a way to mitigate interactions by disguising or muffling the sound of gear retrieval, she said.
To address the lawsuit, NMFS is in the process of creating a false killer whale Take Reduction Team, which will, according to TRT coordinator Nancy Young, include those who filed the petition.
“Hopefully, the TRT can get consensus without litigation,” said Lisa Van Atta, assistant regional administrator for the NMFS PIRO Protected Resources Division.
High Seas Stock
It took time and some prodding to get the NMFS to recognize the Hawaiian stock of false killer whales and now that it is officially a “strategic” stock (a stock where the level of human-caused mortality exceeds the PBR), the agency can, and is obliged to, take steps to mitigate harm. According to Oleson, what she calls the high-seas/Johnston stock is also in trouble, but has not yet been recognized. She said that based on a 2005 abundance estimate of that stock by the Southwest Fisheries Science Center, the number of false killer whales caught by the U.S. fleet exceeds the PBR for that species.
“If it were to exist, it would be considered a strategic stock,” she said.
For Further Reading
- The following articles on false killer whales are available at our online archives, at
- Archive access is free to current subscribers. All others must pay $10 for a two-day pass to view the full articles:
- “New & Noteworthy: Whales on the Line” (November 2005)
- “New & Noteworthy: Whales, Dolphins Unprotected from Fishers” (February 2009)
- “New & Noteworthy: Focus on Cetaceans” (November 2009)
Erin Oleson also reported on NOAA’s attempts to survey cetaceans throughout the Pacific island region, which covers 1.8 million square miles of ocean. Previous surveys have already identified 117 cetacean stocks in the region. Hawai`i has the most, with 34, followed by Guam (17) and the Commonwealth of the Northern Mariana Islands (15). Johnston Atoll and Palmyra both have 14, and Wake, Howland/Baker, and Jarvis have six or fewer.
Collecting additional population data for those stocks and others will not be easy. The cetacean program is relatively new, receiving its first funds – $96,000 – in 2005. Since then, the program has grown to include one to two full-time employees, one to two contract staff, and a small boat. Even so, Oleson noted that it would take 513 days of sea surveying to cover the entire PIRO area.
“We won’t have enough ship time,” she said, adding that her program is working with the Southwest Fisheries Science Center to help cover some of its large-scale survey needs.
Last year, with an annually budget of $365,000, the program surveyed the MHI for abundance of 12 insular species. This year, the program plans to study cetaceans in CNMI, Guam, Palmyra, and Wake. The next large-scale ocean survey will begin in 2011.
In addition to ship-based surveys, the program plans to use acoustic monitoring data to learn more about Pacific cetaceans. She added that her staff is confident it can identify a handful of species, including pilot whales, false killer whales, and Blaineville’s beaked whales, based only on acoustic information.