Results of 2024 Eel Trap Entrance Collection and Data Summary 

By Dr. Carl Berg, Senior Scientist, Surfrider Kauai

Surfrider Kauaʻi’s North Pacific Eel Trap Project is an international, collaborative effort to reduce the number of discarded eel traps and reduce their impact on marine and coastal environment, in particular, the endangered Hawaiian monk seal. 

2024 was a record breaking year for the collection of eel trap entrances (ETE) and eel trap tubes (ETT), with a record of 9,155 ETE and 322 ETT collected from the Hawaiian archipelago. This is 5.8 times the number collected in 2023, likely due to a major shift in ocean currents bringing the North Pacific Garbage Patch closer to the islands.

Weaned Hawaiian monk seal pup hauled out beside another immature seal with an ETE attached to it's snout. Photo courtesy of NOAA Fisheries/Sarah Glover (Permit#22677) 

ETE are cone shaped objects, used primarily by Asian fisheries, to trap eels and hagfish, an eel-like creature. They get loose and travel on ocean currents, landing on Hawaiʻi’s beaches where they can get stuck on the snouts of curious monk seal pups, causing them to starve if they’re not caught and rescued. They also do not degrade and contribute to plastic marine debris and to microplastic pollution of seas. Our four-year total is 21,355 of ETE and ETT from the full range of the Hawaiian island chain. Partners also did collections in Taiwan, Japan, South Korea.

In the first year of the project, which has been supported by the Global Ghost Gear Initiative (GGGI), we had large collections from legacy sites – those that hadn’t been cleaned before. For example, 3,232 traps were collected from a single cleanup on Kaho`olawe Island. The four main large islands of Kauaʻi, Oʻahu, Maui and Hawaiʻi – with regularly scheduled beach cleanups – together averaged 662 pieces of ETEs and ETTs collected and reported each month.

Once we had a sizable collection of traps to examine, we discovered distinct differences between eel traps used by Japanese fishermen and those used by Chinese and South Korean fishermen (photo on right is an example of Japanese branding on ETT). Some of the Japanese style eel trap tubes were branded with the names of the fishing port, boat or fisherman's name – leading us directly to the source. Those areas had been devastated by the 2011 tsunami, so that gear may have been lost by the natural calamity, rather than fishermen discarding broken gear at sea.

Whatever the source, the impact of ETE and ETT marine debris on marine life continues. NOAA (National Oceanic and Atmospheric Administration) reported the 17th rescue of a rare Hawaiian monks seal pup (see photo above), and volunteers on Kauai have reported removing ETE from monk seals sleeping on the beach.

I visited hagfish fishermen on the California coast to learn of their fishing practices and provided them, and fishermen in Alaska and Oregon, with biodegradable ETE that I obtained from a factory in Korea. As the biodegradable ETE do not float and disintegrate on the sea floor, their widespread use would greatly reduce the threat to marine life. Collaborating scientists in California and Rhode Island have designed a new ETE and are testing it with a polymer specifically designed to more quickly biodegrade on the bottom of the ocean, and to break in half so that it cannot get caught on monk seal snouts.

How Can You Help?

If you find an ETE or ETT on a beach near you, please take a photo, send it to hagfish@surfrider.org, and dispose of it properly. Mahalo to GGGI for their support on this project. We’d also like to thank everyone who has participated in this project by sending us pictures of found traps.