A Wildlife Article from All-Creatures.org

Debris in Waterways is Dangerous to Manatees and Other Wildlife

From Save the Manatee Club
May 2022

Fishing line, hooks, and other trash that are discarded can become intertwined in vegetation where manatees feed.

manatee flipper fishing line
Fishing line that was so severely wrapped around Una’s flipper, it cut through bone and skin.

n March 2022, a young manatee named Tama was found unresponsive in shallow water at Blue Spring State Park. She died from monofilament fishing line lesions in the small intestine. “She was otherwise in great condition,” reported staff from the Florida Fish and Wildlife Conservation Commission.

Una and her dependent calf were rescued in February 2020 at Blue Spring State Park because Una’s flippers were severely entangled in monofilament fishing line. This was her second rescue for severe flipper entanglement, which can be a significant problem because calves nurse from mammary glands located behind the mother’s flippers.

Schwinn somehow became completely encircled in a bicycle tire in 2019. Partners from the Manatee Rescue and Rehabilitation Partnership (MRP) attempted several rescues but were unsuccessful. In 2020, he appeared tire free, but he now bears deep scars from the entanglement injury.

bike tire manatee
Schwinn became entangled in a bike tire. He got free but now bears a deep scar.

Mr. Baby was just a young manatee when he was released at Blue Spring State Park in December 2017. He did very well and was observed feeding, socializing, and traveling. But in less than a year, he was reported in Lake Monroe showing signs of distress and died two months later. A necropsy found he had consumed various types of man-made debris.

Lucille and Margarito are two manatees that had to be rescued after fishing line became wrapped around and embedded in their flippers. The line was removed, but Lucille eventually lost the lower half of the flipper, and Margarito lost his entire left flipper.

Debris in our waterways, such as discarded fishing line and hooks, plastic six-pack holders, and plastic bags, is dangerous to manatees and other wildlife.

fish hook manatee
A manatee with a fish hook embedded in its mouth.

As herbivores, manatees graze on a large variety of aquatic vegetation. When they are eating, they use their upper lip and flippers to grasp the vegetation. Fishing line, hooks, and other trash that are discarded can become intertwined in vegetation where manatees feed. Fishing line can get tangled around their flippers, or they may accidentally swallow the line or other trash. Hooks can become embedded in a manatee’s lips, mouth, throat, stomach, or intestine, leading to fatal infections. Line entanglement can also lead to infection. When the entanglement injury is severe, the flipper may self-amputate, or a manatee may need to be rescued and transported to a critical care facility where its infected flipper can be surgically removed.

Crab traps can be another source of problems for manatees. Manatees become entangled in the rope that connects the traps to floating buoys at the water’s surface. Entanglement in rope alone may cause serious injury, but entanglements involving ropes still attached to crab traps can be particularly harmful because the weight of the trap causes more severe entanglement wounds. Manatees often drag these traps for miles, and their wounds may become infected and lead to flipper amputation or death if they are not sighted and rescued promptly.

Entanglements are one cause of manatee injury and death that we can prevent. By boating or fishing responsibly, we can make the aquatic environment safer for manatees and other wildlife.

Here are some tips to help protect manatees and other wildlife:

  • Report sick, injured, or entangled manatees to the Florida Fish and Wildlife Conservation Commission at 1-888-404-3922. Please do not try to cut the entanglement off yourself. For information on reporting manatees outside of Florida, go to savethemanatee.org/rescue.
  • Recycle your trash or throw it away in a proper trash container.
  • Recycle used fishing line. Bins can be found at many marinas, boat ramps, or fishing piers, or at bait and tackle shops. Click the following link to find bin locations in Florida. You can also learn how to make your own recycling bin.
  • Make your own mini-bin out of a tennis ball or other container to keep used line on board your vessel.
  • Participate in a local cleanup event. Check out Save the Manatee Club’s Events page to see cleanups scheduled in Florida. Join the International Coastal Cleanup on September in locations all around the world or join the National River Cleanup and find an event near you.
Manatee fishing lines

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