Entanglement in fishing gear likely caused the drowning death of the 1-year-old Hawaiian monk seal RM90, also known as Mele, National Oceanic and Atmospheric Administration researchers determined.
"It's a hard thing to talk about because she was a special seal and a seal that a lot of us really invested a lot of time and energy into," said Dr. Michelle Barbieri, head of the Hawaiian Monk Seal Research Program at NOAA.
Mele was found dead in waters off the windward side of Oʻahu on May 24. There were no indications of foul play.
After much discussion and analysis, Barbieri said researchers think Mele "probably drowned from entanglement." Before she died, she was found with a fishing hook in her cheek.
"While the hook did not directly cause her death, it is possible that it rendered her more susceptible to entanglement — she had already been entangled and disentangled in the month prior to her death," NOAA wrote in a press release.
Barbieri said a 2019 study found that drowning in lay nets is one of the top causes of death among monk seals in the main Hawaiian Islands — a problem that continues to limit population growth. Lay nets are laid out and left in the water for an extended period of time to catch fish before being brought back in.
"In many cases, we suspect that these are nets that are being fished illegally, that legally fished nets we would hope would mitigate that threat substantially. We really are concerned about this threat," she said. "Unfortunately, for RM 90 (Mele), it means that not only did we lose her to the population, but we also lose the reproductive potential that she had for the species and the pups that she would have given birth to."
Because shore-based lay nets are usually left unattended, seals will come to the net to find fish caught inside, said Ryan Jenkinson, head of the Protected Species Program at the Hawaiʻi Department of Land and Natural Resources.
Though any net left unattended for more than a few hours is in violation, Jenkinson said.
"The best way to avoid this kind of thing is if you're lay net fishing, to be with the net at all times," he said. "If you're around and you see a seal, you can either pull on the net or yell at the seal, it'll be spooked by you."
Recent viral videos of visitors touching Hawaiian monk seals and green sea turtles have sparked public outcry and a demand for more environmental education.
"From the perspective of the state, you can't follow every person who arrives in the Hawaiian Islands and monitor all of their activities. A lot of what we can do is ask the general public to keep their eyes out, and to increase our education and outreach," he said.
"Monk seals are part of the culture. They're part of everyday life here. You don't disrespect them, you don't go up and touch them. You keep a safe distance and just be stoked that you get to see these animals. They're rare," Jenkinson told Hawaiʻi Public Radio.
A new music video by local rap group Angry Locals also sent a strong message to visitors to discourage them from harassing Hawaiʻi’s endangered and federally protected marine wildlife.
This segment aired on The Conversation on July 23, 2021.
