Common Loon - Basic Plumage Common Loon - Breading Plumage
Photos By Joe Halton Photo by Ron Holmes
The Common Loons are back. It's time to look for them in our bays and along our shorelines. Unlike similar sized cormorants who congregate in groups, during winter Common Loons are solitary during the day. At night they will congregate in loose rafts. You've probably seen cormorants on piers or pilings, but Loons stay on the water. Observing these two species as silhouettes in the distance, cormorants sit very low on the waterline with their bills tilted up. Common Loons sit higher and hold their bills level. Both dive for fish and swallow them underwater. Their eyes are adapted for vision above and below water. Cormorants are year-round residents in our area. Common Loons grace our waters during winter. They are a favorite winter resident.
Since Common Loons are winter residents in our area, they are mostly observed in their basic plumage; which means we're seeing shades of gray. Overall length is 32 inches. They have a jet black head and bill in summer with a beautiful checker board white and black pattern on their backs. Winter, their head turns gray with white feathers on their throats and around their eyes. The bill changes to light gray and their backs appear gray-brown. They have a throat pattern of white to gray at the base of the throat which is a distinguishing field mark. Midwinter, Common Loons molt all of their wing feathers and are flightless for a few weeks.
Common Loons are known for their variety of vocalizations. Calls include yodel, wail, tremolo and a hoot. The yodel is performed by the male only. It is a territorial call and is unique to each male within a particular area. If the male changes territories, he will also change his yodel. The wail is a location call and is made by adults and their young. The tremolo is sometimes referred to as the laughing call. This is an alarm call to signal to other loons. It is the only call used in flight. The softest call is a hoot used between adults and chicks. In winter, the Common Loon vocalizes infrequently. The call we are most likely to hear is the tremolo.
You may think that Loons get their name from their crazy calls. The word is actually derived from the word loom which means lame in the language of the Shetland Islands. This refers to how awkward these birds are on land. The position of their legs and feet are set back closer to their tail. This fact along with their heavier bones make them great deepwater divers, but ill-suited for moving on land. They can dive 200 feet and stay underwater up to 3 minutes. Loons have been recorded at depths up to 600 feet on the Great Lakes. Once underwater, their heart slows down to conserve energy. Taking off and landing from the water have challenges too. Depending on wind velocity, Loons need from 30 yards up to a quarter mile to get enough momentum for lift-off. They land by skimming the surface with their bellies to slowdown. Once airborne, loons are efficient fliers clocked up to 75 mph and flying long distances to migrate. In flight, their feet stick out beyond their tail. The oldest known Common Loon lived to be a little over 24 years old.
When breeding, a monogamous pair of Loons will construct their nests on the edge of deep fresh water lakes. Enough depth is important for loons to dive and return to their nests quickly and easily. The nest consists of aquatic plants mixed with nearby grasses and twigs. These nests are perennial and the pair may return year after year. Both parents incubate 1-3 eggs for about 30 days. Adults will protect their nest by performing distraction displays and will even rush at a predator attempting to impale it with their bills. However, they will also leave the nest unattended to feed nearby. The young are born semi-precocial and are fed by both parents on the nest. Within two days the hatchlings will swim near their parents to shallower water to reduce predation from larger fish and turtles. These areas are referred to as the nursery. During the first week young loons spend 65% of their time on the backs of their parents. Time spent in the nursery ranges from 75 to 80 days.
There are three other loons to look for this season in the waters of Skagit County. These include the Red-throated Loon, Pacific Loon and the very rare Yellow-billed Loon. The Common and Yellow-billed loons are very similar with the Yellow-billed being slightly larger. The Yellow-billed has a light colored bill in winter with a very distinctive black patch at the base of the top mandible. The Common Loon's winter bill is all light gray. The Red-throated Loon is the smallest loon at 25 inches. It has a slender silhouette with a slender bill, which it holds tilted up. The Red-throated is much paler than the other loons. The Pacific Loon can be confused with the Common. In basic plumage, the Pacific does not have white around the eyes and lacks the white to gray pattern on the throat like the Common Loon.
Don't go looney searching for loons this winter. The Yellow-billed Loon was observed by several Skagit Audubon Birders last winter off Cap Sante on Fidalgo Island. Red-throated Loons are commonly seen from Rosario Head in Deception Pass. Join one of our field trips heading to the shoreline or just get outside to enjoy winter birding in Skagit County.
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