Protected Species Management Measures

A variety of management measures are in place to reduce the bycatch of protected sea turtle, seabird, and marine mammal species. To read about the specific measures in place for each species group, click on one of the following links:

SEA TURTLES

width= Due to high sea turtle bycatch rates, several time-area closures of the swordfish fishery were implemented after 1999, and a full closure of the swordfish sector of the Hawai‘i-based longline fishery went into effect in 2001. This closure lasted until April 2004. In 2004, a number of sea turtle bycatch mitigation measures went into effect. An analysis of the swordfish longline fishery observer data for the period of 2004-2007 showed that interaction rates of leatherback and loggerhead turtles declined by 83 percent and 90 percent, respectively, compared to pre-regulation interaction rates (Gilman et al. 2007).

The following summarizes sea turtle mitigation measures in the Hawai‘i-based longline fishery:

  • The following regulations apply to all longline vessels (including American Samoa-based vessels):
    • Longline vessel owners/operators are required to adhere to regulations for safe handling and release of sea turtles.
    • Longline vessel owners/operators must have on board the vessel all required turtle handling/dehooking gear specified in regulations.
    • Vessel owners and operators are required to annually attend protected species workshop
  • When shallow-set longline fishing north of the Equator:
    • Use 18/0 or larger circle hooks with no more than 10° offset.
    • Use mackerel-type bait.
    • 100 percent observer coverage.
    • Individual trip interaction limits of 5 loggerhead turtle and 2 leatherback turtles per trip. 
    • Closure for remainder of year when fishery reaches an annual interaction limit (“hard cap”) of 16 leatherback turtles.

Examples of sea turtle handling gear required for Hawai’i-based longline vessels.

Large circle hooks replaced J-hooks when the Hawai‘i-based swordfish longline fishery reopened in 2004.

Mackerel bait replaced squid bait when the Hawai‘i-based swordfish longline fishery reopened in 2004.

When the federal observer program for the American Samoa longline fishery started in 2006, it was discovered that the fishery had occasional green turtle interactions. In 2009, the Council recommended a measure to mitigate green turtle interactions by requiring longline gear configuration in such a way that all hooks are set deeper than 100 meters. Since the measure became effective in 2011, the estimated total interactions have been about seven green turtles per year, a substantial reduction compared to an estimated 30 per year before the implementation.

In the American Samoa longline fishery, owners and operators of vessels longer than 40 ft (12.2 m) must use longline gear that meet the following requirements:

  • Each float line must be at least 30 m long.
  • At least 15 branch lines must be attached to the mainline between any two float lines attached to the mainline.
  • Each branch line must be at least 10 m long.
  • No branch line may be attached to the mainline closer than 70 m to any float line.
  • No more than 10 swordfish may be possessed or landed during a single fishing trip.

To learn more about the sea turtles species that are protected by these measures, click here.

 

SEABIRDS

In 2001, the Council implemented a set of seabird bycatch mitigation measures for the Hawai‘i-based longline fishery, with the full suite of measures going into effect in 2002 through a Framework Adjustment to the Pelagic FMP. The seabird measures, combined with the temporary closure of the Hawai‘i-based swordfish longline fishery in 2001 due to sea turtle interactions resulted in a significant reduction in seabird interactions. Seabird interactions remained low even after the reopening of the fishery in 2004, as fishermen were required to use a combination of mitigation measures at all times. In 2024, Council-recommended revisions to the seabird measures were implemented, requiring the Hawai‘i-based tuna longline fishery to use tori lines in place of blue-dyed bait when stern-setting. 

 Side vs. stern setting (image source: Gilman et al., 2003)

The following summarizes seabird mitigation measures in the Hawai‘i-based longline fishery:

  • The following regulations apply to all longline vessels:
    • Longline vessel owners/operators are required to adhere to regulations for safe handling and release of seabirds.
  • The following regulations apply to tuna-targeting deep-set longline vessels operating at latitudes higher than 23° north and all swordfish-targeting shallow-set longline vessels:
    • When side-setting, vessels are required to:
      • Use bird curtain aft of the setting station
      • Attach weights (45 grams or heavier) within 1 meter of each hook
      • If using a line shooter, mount at least 1 meter forward from stern corner
      • Deploy gear so hooks do not resurface
    • When stern-setting, tuna-targeting deep-set longline vessels are required to:
      • Use tori lines 
      • Use a line shooter and weighted hooks 
    • When stern-setting, swordfish-targeting shallow-set longline vessels are required to:
      • Use blue-dyed bait
      • Use fish parts and spent bait for strategic offal discard
      • Night set—begin set 1 hour after sunset and finish 1 hour before next sunrise

To learn more about the seabird species that are protected by these measures, click here.

 

MARINE MAMMALS

False killer whales are toothed whales found in all tropical and temperate oceans worldwide.

When marine mammal interaction levels are found to be unsustainable under the MMPA, NMFS is required to convene a Take Reduction Team (TRT) to develop recommendations for mitigating the impacts. A TRT was formed for false killer whales in the Hawai‘i longline fishery in 2010, and the TRT was tasked with developing a Take Reduction Plan (TRP) that was implemented in 2012. The TRP requires that the deep-set longline fishery to use “weak” hooks intended to straighten on the weight of a false killer whale but that can withstand the weight of a large bigeye tuna.

Monitoring of the TRP is ongoing, but the effectiveness of the measures intended to minimize injuries has yet to be determined. The low rate of interactions may mean that it will take many years to determine whether measures are working, unlike the significant bycatch reductions seen after the implementation of the Council’s seabird and sea turtle measures.

The Council continues to work with the industry and NMFS to search for long-term solutions to the false killer whale depredation and incidental interaction issues. In 2015, the Council supported the industry in their fleet-wide outreach effort to increase awareness of the importance of straightening a weak hook if fishermen encounter a false killer whale hooking. The Council also worked with the industry to test the commercial viability of a device designed to deter false killer whales from depredating on tuna and other catch.

To learn more about protected marine mammal species, click here.

To learn more about all of these protected species management measures, see the Protected Species Conservation Monograph.