DECEMBER 2020
15
GYRES, GARBAGE & GHOSTS
Why Do We Keep Seeing Marine Debris in Hawaii? by Western Pacific Regional Fishery Management Council (WPRFMC)
■ On March 11, 2011, the Tohoku earthquake and tsunami took the lives of 16,000 people in Japan. This devastation destroyed numerous towns along with thousands of structures. During this event, another notable disaster struck as three Fukushima Daiichi nuclear reactors in the Fukushima Prefecture failed, creating global health concerns over nuclear fallout. Oceanographers feverishly developed maps showing ocean circulation before and after the natural disaster, many of which were infamously used in misinformation to suggest radioactivity issues impacting the entire Pacific basin. Months after the Tohoku and Fukushima tragedies, Japanese appliances were reported to have floated onto U.S. West Coast beaches. While speculation of radioactivity risks was the focus of the tragedy’s looming environmental impacts, 20-25 million tons of timber, fishing equipment, houses, appliances, cars, boats and other debris were lost out at sea. The mass of debris that entered the Pacific was nearly four times the total tonnage of global pelagic fisheries (tunas, billfishes, bonitos) harvested that same year. In addition to the debris from such a disaster, around the world 7 to 16 million tons of plastics alone make their way into oceans. In 2014, a peer-reviewed article published in the science journal PLOS One estimated that along with such debris, some 5.25 trillion plastic particles weighing 269,000 tons are afloat at any given time in the world’s oceans. Unfortunately, a visible hotspot for these plastic particles was identified just a few hundred miles north of the Hawaiian Islands. Known as the Great Pacific Garbage Patch, the large area between Hawai‘i and California consists of trash of all sizes, plastic particles, derelict fishing gear (DFG) and other materials. This is the result of large rotating ocean currents called “gyres” that pull debris into one location forming “patches.” This conveyer belt of oceanographic currents creates a semi-permanent feature of floating trash north of the Hawaiian Islands, which is constantly being fed debris that ends up in the Pacific.
Model prediction of global count density (pieces km−2; see colorbar) for each of four size classes of plastic particles, as estimated by Eriksen et al. (2014). The approximate location of the Great Pacific Garbage Patch is highlighted in yellow. Microplastics are plastic pieces smaller than 5 mm and are difficult to see in the ocean.
Schematic of the Great Pacific Garbage Patch (Eastern Garbage Patch, located in the North Pacific Gyre) and current patterns, Source: NOAA, www.marinedebris.noaa.gov.
Unfortunately, beachgoers often come across DFG and point to local fisheries as the culprits. Recently, it was commented in a local newspaper that the Hawai‘i longline fishery is to blame for all the nets washing ashore on O‘ahu. However, longliners do not use nets of any kind. Others have blamed local fishermen who use other types of gear, not considering the materials commonly used in Hawai‘i fisheries, which often are not the same materials we find washed ashore. Much of the DFG consists of nets from purse seines, driftnets and fish aggregating devices, which are often set by foreign fisheries in the equatorial Pacific Islands. Japan and other distant-water fishing nations used pelagic driftnet fisheries on the high seas for decades, many of which were damaged continued. . . and lost at sea.
DFG washes up on beaches in Kailua. Photo courtsey of Mark Fitchett.
A CAPTIVATING CAUSE
WPRFMC News . . . continued
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Even though international restrictions on driftnets were enacted in 1992, nets are often made of plastic and remain intact for decades. California once had an active pelagic driftnet fishery, which was eventually phased out largely due to protected species issues and the view that “ghost” nets remain highly destructive for decades until their removal. DFG is a major concern due to its threatened safety for marine life and contribution to the marine plastic crisis the globe faces, especially here in Hawai‘i. The Wester n Pacific Regional Fishery Management Council (the Council) has long championed efforts to reduce marine debris in the Pacific. Out of a 1987 international fishermen’s conference on marine debris, held in Kailua-Kona, came the “Fishermen’s Pledge for a Clean Ocean,” which was later adopted or endorsed by five related conferences. Through a partnership with the Hawai‘i fishing industry, the City and County of Honolulu and others, the Council supports the Honolulu Harbor Port Reception Facility for DFG and marine debris. Hawai‘i longline fishermen collect DFG in the North Pacific and offload it at the port where it is then taken to the Honolulu City and County’s H-Power facility for incineration and energy generation. In addition, the Council has worked with suppliers to find alternative fishing gear and fisher men to implement improved fishing practices and provides outreach about DFG and other marine debris at community events. . . . WPRFMC
Adopted by North Pacific Rim Fishermen’s Conference on Marine Debris,Kailua-Kona, Hawai‘i 1987
HAWAII FISHING NEWS
WPRFMC Spotlights the History of Hawai‘i Lobster Fishery by Western Pacific Regional Fishery Management Council (WPRFMC) NWHI Lobster Annual and Cumulative Revenue: 1977-1999
■ The Wester n Pacific Regional Fishery Management Council (the Council) published the first of seven new issues of its Pacific Islands Fishery Monographs historical series. The series aims to take a deeper look into the history and current condition of some of Hawai‘i’s most important fisheries. The series provides a comprehensive view of the social, cultural and economic impacts on Hawai‘i’s fishing industry. “Maya Angelou famously said ‘if you don’t know where you’ve come from, you don’t know where you’re going,’” said Kitty M. Simonds, executive director of the Council. “In this series, the Council is taking a thorough approach in documenting where we’ve been, so policymakers and stakeholders can better chart the future of fishing in Hawai‘i.” The findings and perspectives included in the monographs do not necessarily represent those of either the Council or the National Marine Fisheries Service. The Council hopes that history will expand the reader’s understanding of the diverse views of the fishermen, scientists, managers, policymakers and environmentalists who influence federal fishery management. The goal of the series is to provide a captivating history that respects, as best possible, these multiple factions.
The first of seven new additions to the monograph series and the ninth overall in the series is Northwestern Hawaiian Islands Lobster Fishery, written by Michael Markrich. The monograph charts the history of one of the most lucrative fisheries in the State of Hawai‘i and factors that led to its current closure. Beginning in the 1970s, the Hawaiian lobster fishery quickly boomed in the 1980s, where spiny lobsters similar to those caught off the coast of the Northwestern Hawaiian Islands fueled the growth of “surf and turf” items at fine dining restaurants nationwide. The fishery entered a period of decline during the following decades due to events like expanding marine protected areas in what used to be lobster fishing grounds and creating the marine national monument in the Northwestern Hawaiian Islands. From 1977 to 1999, the fishery was its most active and landed $50 million worth of lobsters. A limited number of printed copies are available on a first-come basis by contacting the Council. The publication and prior issues of the monograph series are also available online at <http://www.wpcouncil.org/educationalresources/education-library/>. . . . WPRFMC
