Birdwatching – American Coot

Northern Flicker cropped

Northern Flicker at S. Lake Howard by Lee

Dan and I went birdwatching last week at South Lake Howard Nature Park here in Winter Haven. We just stopped by on the way home from an errand. Captured a Northern Flicker with the camera, but the video is of the Coot’s feet. I have trying to get a photo of them because they are so different from other bird’s feet. Their feet are not webbed, but sort of flattened out. We only see them down here in the winter. See the Wikipedia information below. Apparently it helps them walk on the land, but it seems that a soft soil just under the water would be “squishy” and that may help their footing. Isn’t it neat how the Lord, in Him wisdom, provided for them in such a way.

O LORD, how manifold are your works! In wisdom have you made them all; the earth is full of your creatures. (Psalms 104:24 ESV)

The American Coot (Fulica americana) is a bird of the Rallidae – Rails, Crakes & Coots Family. Though commonly mistaken to be ducks, American Coots come from a distinct family. Unlike ducks, Coots have broad lobes of skin that fold back with each step in order to facilitate walking on dry land. They live near water, typically inhabiting wetlands and open water bodies in North America. Groups of these black-feathered, white-billed birds are called covers or rafts. The oldest known Coot lived to be 22 years old.

The American coot is a migratory bird that occupies most of North American. They live in the Southwestern United States, Mexico, and the pacific coast year round, and only occupy the northeastern regions during the summer breeding season. In the winter they can be found as far south as Panama. They generally build floating nests and lay 8-12 eggs per clutch. American coots eat primarily algae and other aquatic plants but they do eat animals (both vertebrates and invertebrates) when available.

Much research has been done on the breeding habits of American Coots. Studies have found that mothers will preferentially feed offspring with the brightest plume feathers, a characteristic known as chick ornaments. American coots are also susceptible to conspecific brood parasitism, and identify which offspring are theirs and which are from parasitic females.

The American Coot measures 13–17 in (34–43 cm) in length and 23–28 in (58–71 cm) across the wings. Adults have a short thick white bill and white frontal shield, which usually has a reddish-brown spot near the top of the bill between the eyes. Males and females look alike, but females are smaller. Juvenile birds have olive-brown crowns and a gray body. They become adult-colored around 4 months of age

The American Coot has a variety of repeated calls and sounds. Male and female Coots make different types of calls to similar situations. Male alarm calls are “puhlk” while female alarm calls are “poonk”. Also, stressed males go “puhk-cowah” or “pow-ur” while females call “cooah”

See the Sounds page of All About Birds for the American Coot.

American Coots are found near water—reed-ringed lakes and ponds, open marshes, and sluggish rivers. They prefer freshwater environments, but may temporarily live in saltwater environments during the winter months.

The American Coot’s breeding habitat extends from marshes in southern Quebec to the Pacific coast of North America and as far south as northern South America. Birds from temperate North America east of the Rocky Mountains migrate to the southern United States and southern British Columbia. It is often a year-round resident where water remains open in winter. The number of birds that stay year-round near the northern limit of the species’ range seems to be increasing.

Autumn migration occurs from August to December, with males and non-breeders moving south before the females and juveniles. Spring migration to breeding ranges occurs from large February to mid-May, with males and older birds moving North first. There has been evidence of birds travelling as far north as Greenland and Iceland. It is a rare but regular vagrant to Europe. The American Coot is a highly gregarious species, particularly in the winter, when its flocks can number in the thousands. The picture below is just of one group of hundreds at Viera Wetlands that day (2012)

American Coot (Fulica americana) at Viera Wetlands by Lee

American Coot (Fulica americana) at Viera Wetlands by Lee

The American Coot can dive for food but can also forage and scavenge on land. It is omnivorous, eating plant material, arthropods, fish, and other aquatic animals. Its principal source of food is aquatic vegetation, especially algae. During breeding season, Coots are more likely to eat aquatic insects and mollusks—which constitute the majority of a chick’s diet.

The American Coot is a prolific builder and will create multiple structures during a single breeding season. It nests in well-concealed locations in tall reeds. There are three general types of structures: display platforms, egg nests and brood nests. Egg nests are typically 12 inches in diameter with a 12-15 inch ramp that allows the parents to enter and exit without tearing the sides of the nests. Coots will often build multiple egg nests before selecting one to lay their eggs in. Brood nests are nests that are either newly constructed or have simply been converted from old egg nests after the eggs hatch. They are simply larger egg nests. Egg and brood nests are actually elaborate rafts, and must be constantly added to in order to stay afloat. Females typically do the most work while building.

Females deposit one egg a day until the clutch is complete. Eggs are usually deposited between sunset and midnight. Typically, early season and first clutches average two more eggs than second nesting and late season clutches. Early season nests see an average of 9.0 eggs per clutch while late clutches see an average of 6.4 eggs per clutch. There is an inverse relationship between egg weights and laying sequence, wherein earlier eggs are larger than eggs laid later in the sequence. It is possible to induce a female Coot to lay more eggs than normal by either removing all or part of her clutch. Sometimes, a female may abandon the clutch if enough eggs are removed. Coots, however, do not respond to experimental addition of eggs by laying fewer eggs.

Incubation start time in the American Coot is variable, and can begin anywhere from the deposition of the first egg to after the clutch is fully deposited. Starting incubation before the entire clutch has been laid is an uncommon practice among birds. Once incubation starts it continues without interruption. Male and female Coots share incubation responsibility, but males do most of the work during the 21-day incubation period. Females will begin to re-nest clutches in an average of six days if clutches are destroyed during incubation.

Hatch order usually follows the same sequence as laying order. Regardless of clutch size, eight is the typical maximum size of a brood. Egg desertion is a frequent occurrence among Coots because females will often deposit more than eight eggs. Brood size limits incubation time, and when a certain number of chicks have hatched the remaining eggs are abandoned. The mechanism for egg abandonment has not yet been discovered. Food resource constraints may limit the number of eggs parents let hatch, or the remaining eggs may not provide enough visual or tactile stimulation to elicit incubation behavior. An American Coot can be forced to hatch more eggs than are normally laid. These additional offspring, however, suffer higher mortality rates due to inadequacy in brooding or feeding ability.

American Coot (Fulica americana) by Lee at Lk Morton

American Coot (Fulica americana) by Lee at Lk Morton

The American Coot, unlike other parasitized species, has the ability to recognize and reject conspecific parasitic chicks from their brood. Parents aggressively reject parasite chicks by pecking them vigorously, drowning them, preventing them from entering the nest, etc. They learn to recognize their own chicks by imprinting on cues from the first chick that hatches. The first-hatched chick is a reference to which parents discriminate between later-hatched chicks. Chicks that do not match the imprinted cues are then recognized as parasite chicks and are rejected.

Chick recognition reduces the costs associated with parasitism, and Coots are one of only three bird species in which this behavior has been observed. This is because hatching order is predictable in parasitized Coots—host eggs will reliably hatch before parasite eggs. In other species where hatching order is not as reliable, there is a risk of misimprinting on a parasite chick first and then rejecting their own chicks. In these species, the cost of accidentally misimprinting is greater than the benefits of rejecting parasite chicks.

The first evidence for parental selection of exaggerated, ornamental traits in offspring was found in American Coots. Black American Coot chicks have conspicuously orange-tipped ornamental plumes covering the front half of their body that are known as “chick ornaments” that eventually get bleached out after six days. This brightly colored, exaggerated trait makes Coot chicks more susceptible to predation and does not aid in thermoregulation, but remains selected for by parental choice. These plumes are not necessary for chick viability, but increased chick ornamentation increases the likelihood that a chick will be chosen as a favorite by the parents. Experimental manipulation of chick ornamentation by clipping the bright plumes have shown that parents show clear preferences for ornamented chicks over non-ornamented ones.

The American Coot is fairly aggressive in defense of its eggs and, in combination with their protected nesting habitat, undoubtedly helps reduce losses of eggs and young to all but the most determined and effective predators. American Crows, Black-billed Magpies and Forster’s Tern can sometime take eggs. Mammalian predators (including red foxes, coyotes, skunks and raccoons) are even less likely to predate coot nests, though nests are regularly destroyed in usurpation by muskrats. Conversely, the bold behavior of immature and adult coots leads to them falling prey with relative regularity once out of the breeding season. Regular, non-nesting-season predators include Great Horned Owls, Northern Harriers, Bald Eagles, Golden Eagles, American alligators, bobcats, Great Black-backed and California Gulls. In fact, Coots may locally comprise more than 80% of the Bald Eagle diet.

In culture – On the Louisiana coast, the Cajun word for coot is pouldeau, from French for “coot”, poule d’eau – literally “water hen”. Coot can be used for cooking; it is somewhat popular in Cajun cuisine, for instance as an ingredient for gumbos cooked at home by duck hunters.

(From Wikipedia and All About Birds with editing)

See also:

Birdwatching Trips

Rallidae – Rails, Crakes & Coots Family

American Coot – What Bird

American Coot – All About Birds

American Coot – Wikipedia

Birds of the World

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5 thoughts on “Birdwatching – American Coot

  1. Pingback: Coots in France studied | Dear Kitty. Some blog

  2. Pingback: Coot family story | Dear Kitty. Some blog

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