What is the predator of a common loon?

Quick Answer

The common loon has several natural predators. The main predators of adult loons are bald eagles and great horned owls. Younger loons may also be preyed upon by snapping turtles, northern pike, muskellunge, and walleye. Humans are another significant threat to loon populations.

Predators of Adult Common Loons

Common loons are large diving birds found across Canada and the northern United States. Adult loons can grow up to 3 feet long and weigh up to 12 pounds. Their size helps protect them from many potential predators. However, two predators pose a significant threat to adult loons:

Bald Eagles

Bald eagles are one of the main predators of adult common loons. Bald eagles are large birds of prey that inhabit areas near water across North America. With wingspans over 6 feet, bald eagles are able to snatch loons right off the surface of a lake.

Bald eagles may engage loons in lengthy aerial battles as the loon tries to escape the eagle’s clutches. Eventually the size and strength advantage of the bald eagle prevails more often than not.

Some key facts about bald eagles as loon predators:

• Bald eagles require up to 1.5 pounds of food per day.
• Their preferred food sources are fish and small mammals.
• Bald eagles can attack loons by surprise, overwhelming them before they can escape.
• Battles between bald eagles and loons can last over an hour.
• Bald eagles have been documented drowning loons or carrying them away from the water.

Great Horned Owls

Great horned owls are the other main predator of adult common loons. These large owls hunt at night across much of North and Central America. Their talons are large and powerful enough to seize even the largest loons.

Great horned owls hunt loons at night while they sleep on the water. The loons are unable to see the silent owl approach in the darkness. Some key facts about great horned owls as loon predators:

• Great horned owls have a wingspan up to 5 feet.
• They can exert over 300 psi of force with their talons.
• Their night vision and silent flight give them an advantage over sleeping loons.
• Loons may be carried away from the water back to an owl nest.
• Remains of loons have been found in great horned owl nests and pellets.

Predators of Young Loons

Young loons face threats from some predators that adults are too large for. Young loons fall prey to predators like snapping turtles, large fish, and even muskrats in some cases.

Snapping Turtles

Snapping turtles lurk at the bottom of lakes and ponds, waiting to ambush small waterfowl. They seize young loons from below, dragging them underwater to their doom. Some key facts about snapping turtles as loon predators:

• Snapping turtles have a bite force up to 1000 psi.
• They will consume any aquatic animals small enough to overpower.
• Snapping turtle jaws can detach young loons from adults.
• Turtles may bash loon chicks against rocks to kill them.

Large Fish

Large predatory fish prey on young loons swimming in the lake. Pike, muskie, and walleye attack from below like snapping turtles. Some key facts about large fish as loon predators:

• Pike can grow over 4 feet long and weigh over 30 pounds.
• Muskellunge can grow over 5 feet long and weigh over 55 pounds.
• Walleye over 10 pounds have been known to eat young loons.
• Loons under 3 weeks old are small enough for large fish to swallow whole.
• Fish may rip baby loons away from parents and pull them underwater.

Muskrats

Though not common, muskrats have also been known to prey on young loons close to shore. Muskrats are semiaquatic rodents but are capable swimmers and can attack from the water. Some key facts about muskrats as loon predators:

• Muskrats can grow up to 2 feet long and weigh over 5 pounds.
• They are opportunistic feeders and will eat birds, eggs, and chicks.
• Muskrats raid loon nests close to shore for unattended eggs.
• They may drag baby loons underwater while adults are distracted.

Threats from Humans

While not actively hunting loons, humans pose a significant threat to loon populations. Environmental damage, fishing equipment, and lead poisoning are some ways humans endanger loons.

Environmental Damage

Humans cause environmental damage that destroys loon habitats and breeding ground. Some key dangers include:

• Pollution – Contaminants poison waterways and fish loons eat.
• Acid Rain – Makes waters acidic and depletes food sources.
• Shoreline Development – Destroys nesting sites and wetlands.
• Climate Change – Causes habitat loss as waterways dry up.

Fishing Equipment

Fishing gear causes injury and death to many loons each year. Some key dangers from fishing equipment:

• Fishing Line Entanglement – Birds get tangled in line, lose circulation, and drown.
• Swallowed Fishing Hooks – Hooks get caught in loon’s throats or stomachs.
• Lead Sinkers – Loons ingest lead sinkers when grabbing pebbles for their gizzards.

Lead poisoning

Lead poisoning from ingested fishing sinkers is a major cause of loon deaths. Some key facts about lead poisoning in loons:

• Loons ingest pebbles to grind food in their gizzards.
• They mistake lead sinkers for pebbles.
• Lead poisons their nervous systems once dissolved in their stomachs.
• An estimated 10,000 loons die annually from lead poisoning.
• Bans on lead fishing tackle have helped reduce loon mortality.

How Loons Defend Against Predators

Common loons have adaptations that help defend themselves and avoid predators:

• Camouflage – Their dark black/white plumage blends into the water.
• Speed – Loons can swim underwater at speeds up to 60 mph.
• Diving – They can dive over 200 feet to escape predators.
• Mobbing – Loons work together to chase predators from their territory.
• Cries – Their wailing cries alert other loons to danger.

By diving deep and flying away quickly, loons can often escape attacks. But predators still take a heavy toll, especially on vulnerable chicks. Proper management is needed to ensure loon populations remain stable.

Conclusion

The common loon faces predators from all domains – air, land, and water. Bald eagles and great horned owls are formidable airborne predators. Snapping turtles, large fish, and muskrats threaten from the water. And human activity destroys much of their breeding habitat.

Loons have adaptations to help them survive like camouflage, speed, diving ability, and cooperative mobbing of predators. But they remain vulnerable, especially babies and nesting females. Monitoring and protection of loon habitats are critical for maintaining thriving loon populations across North America alongside their diverse predators.