Monofilament fishing line and fishing gear impact birds
While conducting my Matagorda Peninsula shorebird survey in October, I came across a disturbing sight. This strikingly beautiful large shorebird with a long curved bill—a Long-billed Curlew—was skewered with fishing gear through its flank. Since October, I have seen this bird in the same general location on each subsequent Matagorda beach survey. However, each time I try to capture the bird, he flies back into the marsh behind the dunes. I surmise the bird is foraging in the marsh, but then moving to the beach (where they are not commonly observed) to rest where vegetation doesn’t aggravate the wound with dangling fishing gear. Although the individual has survived now approximately three months, I wonder when the monofilament attached to the jig will become entangled resulting in the bird’s slow starvation or depredation by a coyote.
While doing a beach survey this past summer, I was contacted by Oron Atkins who was on sea turtle patrol at Matagorda when he encountered a Magnificent Frigatebird with both legs badly tangled in monofilament fishing line and unable to fly. I met up with Oron and his assistant/wife Marie, and together we were able to remove the line, but the bird was in a weakened state. Luckily, we had the support of Cherie Allen of Bay City Wildlife Rescue where our frigatebird was delivered, rehabilitated, and five days later made a long high flight from the Matagorda Pier to our cheering group. Without this teamwork, it is unlikely the bird would have lived another day.
Director of Research at the Gulf Coast Bird Observatory, Dr. Susan Heath, published an article on occurrence of monofilament fishing line entanglement by her primary study birds, American Oystercatchers. In six years of research, she encountered five cases of oystercatcher entanglement or 2-4% of her study population. Two cases resulted in death, one case probably resulted in death, and two cases resulted in survival of the entangled oystercatchers due to human intervention. In her article, Dr. Heath describes each of the five cases. In one case, Heath had banded the bird as a chick in Galveston Bay; the bird was three months old when it was found in a moribund condition on the Texas City Dike. Although the bird was taken to a wildlife rehabilitator, he was severely underweight and died a short time later. Necropsy of this young male revealed he was emaciated, with a bolus of monofilament blocking his alimentary tract—the bolus consisting of five different types of monofilament (different colors and diameters)! In another case, Heath had banded an adult female breeding in West Galveston Bay; three years later, she was first found on Bolivar Peninsula and then Rollover Pass two days later. She was in a moribund state with monofilament line wrapped around both feet. Her feet were in such extreme decomposition shown in a horrific photo accompanying the article that she had to be euthanized.
These are just a handful of thousands of cases of bird entanglement discovered every year, as well as many birds who succumb before discovery. A multitude of plastics litter our oceans, but especially lethal are the discarded monofilament lines and hooks used by recreationists, which seem to me to be an easily preventable issue compared to many other abiotic environmental hazards—if the angler understands the potential harm and has a conscious! Instead of leaving that snapped off piece of monofilament with hook hanging from the bush, take responsibility for your gear and dispose of it properly so that others do not suffer. If you are not the angler who left the trash, but you find it in your path, please take a few minutes to put it where it belongs rather than left to entangle some unsuspecting creature.