COMMON LOON BEHAVIORS

Loons exhibit many displays and behaviors that allow the observer to interpret why a loon may be acting in a particular manner. Most loon behaviors are related to basic survival skills, such as feather maintenance, feeding, territorial defense, and protection of their chicks.

Feather Maintenance

Loons take baths and preen regularly to keep their feathers clean and waterproof. While bathing, loons roll, splash water about, and wing flap repeatedly, which can be mistaken for a bird in distress. Baths can last a ½ hour or more, before the bird settles down and begins to preen in earnest.

Loons preen their feathers to keep them properly aligned for flight and waterproof for swimming and diving. A small gland, the uropygial gland, located near the tail produces oil which the loon rubs on the surface of its feathers to keep them waterproof. Loons squeeze a bit of oil from the gland, then rub their heads on their backs to waterproof the feathers on their head and neck, which are very difficult to reach.

Occasionally, loons hold a foot above the surface of the water, especially when preening their white belly. They also “foot wag” to stretch their legs or to regulate their body temperature. If a loon is banded, it is easy to see the bands when it does a foot wag.

(pics of loon with feet in the air, head back, foot wag with bands).

Feeding

Loons “peer” by submerging their head under water to see what is swimming beneath. Loon chicks often peer to watch their parents catch fish to feed the chicks. Once a fish is located, the loon dives, holding its wings close to its body, and uses its powerful feet for propulsion while swimming underwater. The fish is captured in the bill, and with the exception of large individuals, is consumed while still underwater. If the loon catches a large fish, it may release and catch the fish repeatedly until it is subdued, and the loon can swallow it whole. When feeding chicks, adult loons catch small fish one at a time, and hold it sideways in their bill to bring the fish to the chicks.

(pic of loon peering, catching big fish, feeding chick small fish)

Loon Socialization

Loons are often observed congregated in social gatherings, which consist from a few individuals to several dozen birds. Loons really are very social animals when they are not defending a territory or chicks. They gather together to feed, often doing a “circle dance”, in which the birds swim in a circle, taking turns peering and diving into the water.

During the summer, these groups generally consist of individuals that are single or did not successfully nest, but occasionally a bird with chicks will leave its mate to care for the young while it goes off to feed with its friends. Prior to migration, the size of these gatherings can increase to several dozen birds. Juvenile birds also gather together in social groups prior to migration. These social groups may serve to help with feeding, as there are many more eyes to look for fish and beaks to catch them.

(pic of many loons together)

Courtship, Nesting, and Raising Chicks

In the spring, males migrate back to their breeding lakes before the females to establish and set up a territory for nesting. The pair usually returns to the same territory year after year. Courtship behavior is very subtle and quiet, including side-by-side swimming, bill dipping, circling, and soft hoots between the pair.

The birds nest on the shore of an island, bog mat, log, or even a large rock. Their nests vary from a shallow scrape to a large (~1-2 feet across) bulky bowl of vegetation.

One or two (rarely three) large (~3-4 inches long) oval eggs are laid in late May-early June. The eggs are olive-green to brown in color and often have brown spots. They are well camouflaged in the nest if the parent goes off to eat or bathe.

Both adults incubate the eggs for ~26-30 days until the chicks hatch. If the birds are disturbed by a predator, another loon, or a human while incubating they can hurriedly scramble off the nest to get back in the water.

Alternatively, some birds are “stickers” and will remain on the nest until they absolutely have to move. If they feel threatened, they may “freeze” in the hangover position, which enables the bird to “hide” itself in the vegetation, and minimizes the chances that a predator would see it. Loons can also easily slip into the water from this position, since their head is very close to the water. If you observe a loon in a hangover, it is likely that you might be too close to the nest for the bird’s comfort. Try moving away (you might have to move a long ways – even to the other side of the lake) and looking through binoculars. After a while, you should see the loon resume a normal incubating position with its head up in the air. (pic of loon in hangover position)

The chicks are little black, downy “puff-balls” after they hatch. The first egg laid hatches first, and that chick is a little bigger than the other chick(s). The chicks establish a dominance hierarchy by fighting the first day or two of their lives. The larger chick has the advantage and becomes the dominant chick, getting fed first by the parents. Sometimes, if food is limited, the dominant chick grows at a faster rate than the other chick(s) because it gets fed more and receives more care from the parents. Occasionally the younger chick(s) dies because it is not getting enough food or care.

Once the chicks hatch, they ride on their parents’ backs for the first two-three weeks of life. Back riding protects them from underwater predators and keeps them warm when they snuggle into the soft down under their parent’s wings. (pic of chicks on back)

General Visual Displays (pics of different displays here as appropriate)

The posture of the loon is very indicative about how it is feeling, and are important to understand so that observers can respond appropriately depending on how the loon is behaving.

Hiding position: The loon is riding very low (almost flat) on the water. This position, often used by juveniles when they feel threatened, provides camouflage from predators, and the bird is able to quickly dive to get away from a threat.
Head high with distinct bump on the forehead: This position means that the loon is alert, and slightly concerned by a possible threat, such as a predator, another loon, or human/boat.
Penguin dance: This is an aggressive display, usually done by the male, to defend its territory or chicks from another loon invading its territory, a predator, or a boat/humans. This display takes a lot of energy to do, and the bird may do it repeatedly until the perceived threat moves away. Two males will penguin dance at each other when they are fighting over a territory.
Splash diving: A loon will quickly “splash dive” when it is feels threatened – this is a very sharp dive that is accompanied by a splash as the loon enters the water. The bird often “squawks/yelps” as it dives. If you see a loon splash diving, it is probably upset about something and is trying to get away.
Wing rowing: Wing rowing is most often observed when two loons are fighting, and one is trying to get away from the other bird. The loon moves rapidly across the water, propelled by its wings “rowing” through the water. During a fight, there is also usually a lot of calling, tremolos and yodels, and splashing, creating quite the commotion as the birds chase each other back and forth across the lake. Occasionally, a bird will wing row just to move quickly to a different part of the lake. In these instances, you would only observe one loon wing rowing, and there probably wouldn’t be any calling.

Looks like a loon? Is it a loon?