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Photostory - Monk Seal Lay Gill Net


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Tangled Catch: Other Monk Seal and Gill Net Facts

Keeping Watch

Volunteers had been protecting the pup in a cordoned beach area for 50 days while her mother nursed her. Once weaned and able to care for herself, the pup, named Penelope, was moved by NOAA and volunteers to a small island offshore that offered a more sheltered area. The new location did not prevent her from swimming to Oahu, where she became entangled in a lay gill net near a windward shore pier.

Hawaiian monk seals are endangered, with a current population of about 1,250, and only about 75 remaining in the main Hawaiian Islands. Low juvenile survivorship puts them at risk of extinction. Penelope was the first monk seal pup born on the main island of Oahu in eight years, and the first-ever recorded female to be born there.

Lay Gill Nets
  • Modern lay gill nets are constructed of monofilament nylon mesh, a relatively cheap material, and cost around $100. The nets, usually measuring 125 x 7 feet, can be sewn together to form long nets of hundreds and even thousands of feet.
  • Traditional Hawaiian gill nets were woven of shredded fiber and were highly valued among fishermen, who were careful to deploy and retrieve them in a timely manner, reducing their impact on other organisms on and around the coral reef.
  • Gill nets are so-called because the mesh allows a fish’s head to pass through the net, but then traps it by the gills. The mesh can then bind a fish’s gills, slowing the flow of oxygen and effectively drowning the fish before the fisher returns to check his or her net.
  • Lay gill nets are often left unattended for many hours or through the night, but the proposed rule would ban overnight use and require regular checks.
  • Gill nets are arbitrary and efficient killers, and often capture fish that are smaller than the legal minimum size.
  • Nylon does not degrade quickly. If nets become entangled in coral and are then abandoned, they will ‘ghost fish’, needlessly ensnaring and killing fish over and over again for years.
  • A gill net ban in 1987 in Hilo Bay, Hawaii has resulted in increased size of the main fish species previously caught by gill nets, and a gill net ban in Fiji has resulted in more productive fisheries there.
  • Public opinion research recently conducted by Fair Catch shows that, once informed of the dangers of lay nets, 76% of Hawaii residents support the state’s proposal to restrict their use.

Scientist’s Report: The Case Against Lay Gill Nets

Monterey Bay Aquarium website: how fish are caught

Monk Seals
  • The Hawaiian monk seal, Monachus schauinslandi, has received special protection under the Endangered Species Act since 1976 is listed as an endangered species.
  • These seals weigh approximately 400 (up to 600) pounds as adults and grow to seven feet in length.
  • Monk seals have not evolved significantly in 15 million years, and are therefore considered ‘living fossils’.
  • Hawaiian monk seals are one of the most endangered marine species in the United States, and although their marine range is expansive, they come to shore mainly in the northwestern Hawaiian Islands.
  • There are three species of monk seal, Hawaiian, Mediterranean, and Caribbean. All are endangered.
  • All marine mammals are protected under the Marine Mammal Protection Act.

National Marine Fisheries Service (NMFS) pinnipeds fact sheet

NOAA Marine Mammal Protection Act facts

NMFS Endandered Species Act facts

Additional Web Links
  • Fair Catch (Partnership of The Nature Conservancy, Malama Hawai`i, and SeaWeb)
  • Fair Catch public opinion research report
  • Fair Catch Press Room
  • Monk seal Penelope drowns in gillnet (by Diana Leone, Honolulu Star Bulletin)
  • Seal's death shows need for gillnet rules (Honolulu Star Bulletin opinion piece)
  • Seal pups pack up for trip home (by Nelson Daranciang, Honolulu Star Bulletin)
  • Scientists’ Report: The Case Against Lay Gill Nets
  • Race on to stem decline of seals (by Tara Godvin, Associated Press)

Compiled by the Marine Photobank.