Red-throated loon
The Red-throated Loon, also known as the Red-throated Diver, is a remarkable aquatic bird that exhibits exceptional swimming and diving abilities. This species, the smallest among loons, ranges widely across the northern hemisphere and is easily identified by its light gray plumage, dark red neck patches in summer, and unique white stripes on its neck. With a body length of 24 to 27 inches and weighing between two to five pounds, these loons primarily inhabit lakes in forested, taiga, and tundra regions during the breeding season.
Red-throated Loons are adept hunters, preying on fish, crustaceans, and amphibians, and can dive up to 30 feet deep for extended periods. They are monogamous and engage in courtship displays that include synchronized swimming and bill dipping. Nesting typically occurs close to water, where both parents share the responsibilities of incubation and chick rearing. The chicks are unique in that they often ride on their parents' backs while swimming.
Despite their adaptability, Red-throated Loons face significant threats from environmental changes, pollution, and habitat destruction. Their haunting calls, which range from low quacks to high-pitched wails, contribute to their allure. With a lifespan that can exceed 25 years, understanding and protecting this species is crucial for maintaining their populations in the wild.
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Red-throated loon
The red-throated loons range across more of the world than the other three loon species. They are also called red-throated divers because of their characteristic swimming and diving skills.
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Gaviiformes
Family: Gaviidae
Genus: Gavia
Species: Stellata
Red-throated loons have light gray plumage, or feathering, on their heads. In the summer, they have dark red patches on their slender necks. Their backs are dark gray and brown, and their underparts are white. In the winter, their backs develop white speckling. Their necks have vertical white stripes in a pattern different from the other species. They have slender, upturned bills. Their sleek bodies are 24 to 27 inches (61 to 69 centimeters) long and weigh two to five pounds (one to three kilograms). They are the smallest and live further north than the other loon species.
These aquatic birds catch fish up to seven inches (15 centimeters) long. They also eat crustaceans, crayfish, shrimp, leeches, and frogs. Red-throated loons usually swim around 30 feet (10 meters) deep and can swim several hundred feet (meters) underwater because of their webbed feet. Dives may last several minutes. Loons adjust how low in the water they swim or how deep they dive by changing the position of their feathers and the amount of air in special air sacs.
These loons mate for life. Their courtship behaviors include diving and swimming past one another and quickly dipping their bills in the water. Because red-throated loons can not walk well on land, the male and female build nests within a few feet (one meter) of the water on islands, islets, or on perches like logs and rocks poking out of the water. The nest is a pile of mud, grass, reeds, and other vegetation. Red-throated loons may nest in loose colonies, while the other three loon species usually nest alone.
The female usually lays two brown or olive green eggs with black spots. The eggs are around 3 1/2 inches (nine centimeters) long and 2 inches (five centimeters) wide and weigh between four and six ounces (120 to 170 grams). Both parents incubate the eggs until they hatch 24 to 29 days later. Both parents care for and feed the young insects and small invertebrates (animals without backbones).
The chicks leave the nest within one day of hatching to go to the water and dive. The parents continue to brood the chicks, which means they protect and warm them, covering them with their wings and bodies. The loon parents are unusual because they often carry their chicks on their backs when swimming. The chicks fly for the first time at 7 weeks old and care for themselves after 8 to 11 weeks.
Red-throated loons face many environmental problems. Quick or large water level changes cause plants and animals in the water to die. Tiny organisms called bacteria begin living in the dead and decaying plants and animals. Hot weather and shallow water cause the bacteria to grow faster. When the loons eat the plants or animals, they also eat the poisonous bacteria. The bacteria cause a disease called botulism which kills loons. Acid rain, oil spills, and other forms of pollution harm or destroy the habitats of loons.
Like the other loons, red-throated loons are known for their low quacks, clucks, deep groans, and high-pitched wailings.
In the summer, red-throated loons live in the northern hemisphere on lakes in the forest, taiga, and tundra regions. At the end of summer and breeding season, groups move to coastal saltwater. Some spend the winter in the Great Lakes region or other large freshwater bodies. They return to the same territories and nests in the spring.
The life span of these loons is long, averaging 9 years, with many regularly reaching 25 years.
Bibliography
"Red-throated Loon - Gavia Stellata." PBS, nhpbs.org/wild/RedthroatedLoon.asp. Accessed 15 Apr. 2024.
"Red-throated Loon." National Audubon Society, www.audubon.org/field-guide/bird/red-throated-loon. Accessed 15 Apr. 2024.