Pied-billed grebes breed on the Alaskan coasts, and throughout Canada and the United States. They also breed in some areas of the Caribbean, such as Bermuda and the West Indies and in South America to central Chile and southern Argentina (American Ornithologists' Union, 1998; McLaren, 1998).
Pied-billed grebes migrate with other birds from the northern United States and Canada where bodies of water tend to freeze to southern parts of North America and along South America and the Caribbean (Muller and Storer, 1999).
Biogeographic Regions: nearctic (Native ); neotropical (Native )
Known predators of pied-billed grebes include glaucous-winged gulls, great horned owls, American coots, bald eagles, peregrine falcons, cottonmouths, American alligators, snapping turtles, Norway rats, raccoons and mink.
When threatened by a predator, pied-billed grebes may swim away or dive away and resurface hidden among vegetation with only their eyes and nostrils showing. Adult grebes may also flap their wings, fake injury, and vocalize to distract and lure predators away from their nest (Rockwell, 1910; Allen, 1914; Gabrilson, 1914; Wetmore, 1920; Miller, 1942) . They may also lunge at the predator to drive it away. Adults will sometimes carry threatened chicks on their back away from a predator. Chicks may hold onto their parent's tail with their bill and can even hold on while swimming under water for a long distance to escape predators.
Known Predators:
In breeding season, pied-billed grebes have dark brownish plumage on their upper parts and grayish plumage on the sides of their neck and flanks. They have a black patch on their throat with a whitish outline; the black extends to the malars. They have a conspicuous white ring around the eye. Their bill has a slight hook and is very distinct in breeding season when it has a bluish white color with a distinct black vertical bar. The belly and underwing are whitish as are the under tail-coverts (Godfrey, 1986).
The winter plumage tends to consist of a pale throat, and a fleshy colored bill with no black markings. Upper parts are similar to breeding plumage, however, the sides of the neck and flanks are reddish brown.
The only distinguishing characteristic of juvenile plumage is that the bill is a dull orange color and there are sometimes white markings on the side of the head. Sexes are alike (Muller and Storer, 1999).
Pied-billed grebes weigh 253 to 568 g, are 30.5 to 38.1 cm long and have a wingspan of 16 cm on average.
Range mass: 253 to 568 g.
Average mass: 450 g.
Range length: 30.5 to 38.1 cm.
Average length: 33.02 cm.
Average wingspan: 16 cm.
Sexual Dimorphism: sexes alike
Other Physical Features: endothermic ; bilateral symmetry
There is little information available on pied-billed grebes lifespans. However, grebes are thought to be long-lived birds. One wild pied-billed grebe is thought to have lived at least five years.
Range lifespan
Status: wild: 5 (high) years.
During the breeding season, pied-billed grebes reside in freshwater ponds or lakes to moderately brackish waters. They usually live in areas with emergent or aquatic vegetation which provides good nest site locations. In the winter season, they use the same type of habitat as long as the water is not frozen.
Habitat Regions: temperate ; terrestrial ; freshwater
Aquatic Biomes: lakes and ponds; rivers and streams; brackish water
Wetlands: marsh
Other Habitat Features: agricultural ; riparian
Pied-billed grebes feed on what is most readily available and is not too big for them to grip with their bill. Usually they eat small fish, crustaceans (in particular crayfish), and aquatic insects and their larvae. Some examples of potential food items include crayfish, beetles, minnows, leeches, sticklebacks, and sunfish.
Pied-billed grebes obtain water by dipping thier bill into the water, and then tipping their head back.
Animal Foods: fish; insects; terrestrial non-insect arthropods; terrestrial worms; aquatic crustaceans
Primary Diet: carnivore (Piscivore , Insectivore , Eats non-insect arthropods)
Pied-billed grebes affect populations of their prey. They are also host to some internal and external parasites.
Pied-billed grebes are a focus of ecotourism and much research.
Positive Impacts: ecotourism ; research and education
Pied-billed grebes eat small fish which may impact populations of economically important fish.
Degradation and destruction of their wetland habitat threaten populations of pied-billed grebes. They are also affected by poisoning from pesticides and other contaminants, such as DDE and PCB. Other sources of mortality include entanglement in fishing lines, accidental shooting when they are mistaken for ducks, and collision with man-made objects such as television towers.
Pied-billed grebes are protected by the US Migratory Bird Treaty Act, but are not listed on the US Federal List, or by CITES or the IUCN.
US Migratory Bird Act: protected
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
IUCN Red List of Threatened Species: least concern
Pied-billed grebes use vocalizations and very complex and varied visual displays to communicate in courtship and in territorial matters. During courtship, the male and female of a pair may vocalize in a duet. The songs of pied-billed grebes can vary from a series of calls that sound like "wup, whut, kuk" which continually increases to a "cow" followed by a high pitched "kuk" and low pitched "kow" (Deusing, 1939; Simons, 1969; Godfrey, 1986).
Communication Channels: visual ; acoustic
Other Communication Modes: duets
Perception Channels: visual ; tactile ; acoustic ; chemical
Like other grebes, P. podiceps is monogamous on a seasonal or multi-seasonal basis. However, unlike other grebes, it has no intricate courtship display. Courtship has five different stages: Advertising, the Pirouette Ceremony, Ripple Dive, Circle Display, and Triumph Ceremony.
Advertising marks the beginning of courtship, swimming around with sleek feathers and elongated neck allow the single bird to let birds of opposite sex take notice of his or her availability. In the pirouette ceremony, each bird approaches the other and then takes an upright posture and may give a greeting call followed by a series of head turning jerks. The Ripple Dance involves dives and races underwater to show the other bird his or her swimming prowess. The Circle Display is self explanatory and can be initiated by either sex; during the Circle Display the pair are several meters apart on the water surface. The Triumph Ceremony, which takes place after mates have been established, consists of each mate circling around the other in a stooped position.
Mating System: monogamous
Pied-billed grebes first breed when they are one or two years old. Grebes breeding in the north raise one brood each summer. Some pairs breeding in the south may raise two broods in a summer. Pied-billed grebe nests float and are anchored to marsh vegetation in shallow waters. Both sexes gather soft, flexible, decomposed or fresh plants from the lake bottom to construct the nest. The nest itself resembles a bowl (Muller and Storer, 1999).
The eggs are oval in shape and are bluish white to greenish white and occasionally turquoise. Within two days, the eggs become white and then take on the nest stains and turn brown (Muller, 1995). The typical clutch size is between two and ten (Glover, 1953) with incubation between 23 and 27 days. The chicks are able to leave the nest within an hour of hatching, usually by climbing onto a parent's back. They become independent from their parents within 25 to 62 days.
The breeding season for pied-billed grebes begins in approximately April or May and continues through about October.
Breeding interval: Pied-billed grebes breed once per year. Pairs in the southern part of the range may raise two broods during a single breeding season.
Breeding season: Pied-bill grebes begin breeding around April or May and continue through about October.
Range eggs per season: 2 to 10.
Range time to hatching: 23 to 27 days.
Range time to independence: 25 to 62 days.
Range age at sexual or reproductive maturity (female): 1 to 2 years.
Range age at sexual or reproductive maturity (male): 1 to 2 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; oviparous
Both male and female pied-billed grebes incubate the eggs. The chicks are precocial and can swim and dive immediately after hatching. However, parents continue to protect the chicks for several weeks, and often carry them on their backs. The parents feed the chicks from the time they hatch until they become independent, up to 10 weeks after hatching.
Parental Investment: precocial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Protecting: Male, Female); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male, Female); pre-independence (Provisioning: Male, Female, Protecting: Male, Female)
A small (13 inches) grebe, the Pied-billed Grebe in summer is most easily identified by its gray-brown body, black chin, and conspicuous black bill stripe. In winter, this species loses its black facial adornments, becoming plain gray-brown overall. Male and female Pied-billed Grebes are similar to one another in all seasons. The Pied-billed Grebe breeds across much of the United States, southern Canada, and the northern half of Mexico. In winter, northerly-breeding Pied-billed Grebes abandon their breeding grounds and migrate south as far as southern Mexico and Central America; populations that breed further south are non-migratory. Other non-migratory populations exist in the West Indies, at isolated sites in Central America, and in South America south to central Argentina. Pied-billed Grebes breed on small lakes and ponds, preferring heavily vegetated areas for nest-building and more open areas for feeding. This species utilizes similar habitat types in winter as in summer. Pied-billed Grebes primarily eat small fish, insects, and crustaceans. In appropriate habitat, Pied-billed Grebes may be observed floating low in the water, periodically diving down to capture prey. Many birdwatchers learn to appreciate the Pied-billed Grebe’s ability to quickly sink into the water with minimal surface disturbance when, after returning their attention to the water after a momentary distraction, they discover the bird has “vanished” without a trace. Pied-billed Grebes are primarily active during the day, but migrating birds fly mainly at night.
A small (13 inches) grebe, the Pied-billed Grebe in summer is most easily identified by its gray-brown body, black chin, and conspicuous black bill stripe. In winter, this species loses its black facial adornments, becoming plain gray-brown overall. Male and female Pied-billed Grebes are similar to one another in all seasons. The Pied-billed Grebe breeds across much of the United States, southern Canada, and the northern half of Mexico. In winter, northerly-breeding Pied-billed Grebes abandon their breeding grounds and migrate south as far as southern Mexico and Central America; populations that breed further south are non-migratory. Other non-migratory populations exist in the West Indies, at isolated sites in Central America, and in South America south to central Argentina. Pied-billed Grebes breed on small lakes and ponds, preferring heavily vegetated areas for nest-building and more open areas for feeding. This species utilizes similar habitat types in winter as in summer. Pied-billed Grebes primarily eat small fish, insects, and crustaceans. In appropriate habitat, Pied-billed Grebes may be observed floating low in the water, periodically diving down to capture prey. Many birdwatchers learn to appreciate the Pied-billed Grebe’s ability to quickly sink into the water with minimal surface disturbance when, after returning their attention to the water after a momentary distraction, they discover the bird has “vanished” without a trace. Pied-billed Grebes are primarily active during the day, but migrating birds fly mainly at night.
The pied-billed grebe (Podilymbus podiceps) is a species of the grebe family of water birds. After the extinction of the Atitlán grebe (Podilymbus gigas), the Pied-Billed Grebe became the sole extant member of the genus Podilymbus.[2] The pied-billed grebe is primarily found in ponds throughout the Americas.[3] Other names of this grebe include American dabchick, rail, dabchick, Carolina grebe, devil-diver, dive-dapper, dipper, hell-diver, pied-billed dabchick, pied-bill, thick-billed grebe, and water witch.[4][5]
The pied-billed grebe was described by Carl Linnaeus in the 10th edition of his Systema Naturae in 1758 as Colymbus podiceps.[6] The binomial name is derived from Latin Podilymbus, a contraction of podicipes ("feet at the buttocks", from podici-, "rump-" + pes, "foot")—the origin of the name of the grebe order—and Ancient Greek kolymbos, "diver", and podiceps, "rump-headed", from podici- + Neo-Latin ceps.[7]
Outside its own genus, the closest relatives of the pied-billed grebe are the small grebes of the genus Tachybaptus.[8]
Pied-billed grebes are small, stocky, and short-necked. They are 31–38 cm (12–15 in) in length, with a wingspan of 45–62 cm (18–24 in) and weigh 253–568 g (8.9–20.0 oz).[10] They are mainly brown, with a darker crown and back.[11] Their brown color serves as camouflage in the marshes they live in.[12] They do not have white visible under their wings when flying, like other grebes.[13] Their undertail is white[11] and they have a short, blunt chicken-like bill that is a light grey color,[3][11] which in summer is encircled by a broad black band (hence the name). In the summer, its throat is black.[3] There is no sexual dimorphism.[13] Juveniles have black and white stripes and look more like winter adults.[3] This grebe does not have webbed feet. Its toes have lobes that come out of the side of each toe. These lobes allow for easy paddling.[3] When flying, the feet appear behind the body due to the feet's placement in the far back of the body.[11] Because of the feet placement, they are not able to walk on land.[14]
These grebes may be confused with the least grebe, although that species is much smaller and has a thinner bill. Other similarly sized grebes are very distinct in plumage, i.e. the eared grebe and horned grebe. Both species bear much more colorful breeding plumage, with rufous sides, golden crests along the side of the head against contrasting slaty color (also a rufous neck in the horned); while in winter, both the eared and horned grebes are pied with slaty and cream color and have red eyes. Because of the pied-billed grebe's duck-like habits, some inexperienced observers may confuse it with a duck.[15] However, pied-billed grebes have a very different bill shape (shorter, pointed at the tip, and flattened along the sides), as well as being shorter-necked and shorter-bodied than a duck. Also, unlike ducks, the closest living relatives of the grebe family are flamingos.[16]
Its call is unique, loud and sounds like a "whooping kuk-kuk-cow-cow-cow-cowp-cowp."[17] Its call is similar to the yellow-billed cuckoo.[12]
They are most commonly found throughout North America, Central America, the Caribbean, and South America year round. During the summer breeding season, they are most prevalent in central, northern and northeastern Canada.[3] If they live in an area where the water freezes in the winter they will migrate. Migrating birds generally meet with year-round birds in September and October.[18] They migrate at night.[3] Most migratory birds leave in March or April.[18] They make occasional appearances in Europe and Hawaii.[3] In the United Kingdom, pied-billed grebe visits have numbered 45 sightings as of 2019, appearing generally in October to January.[19] One bird in England bred with a little grebe, producing hybrid young.[20] It is the only grebe on record to have visited the Galapagos Islands.[21]
Pied-billed grebes are found in freshwater wetlands with emergent vegetation, such as cattails.[17] They are occasionally found in salt water. When breeding they are found in emergent vegetation near open water, and in the winter they are primarily found in open water due to the lack of nests to maintain. They may live near rivers, but prefer still water. They may be found in higher elevations when migrating.[18] They will breed in restored and man-made wetlands.[18]
Pied-billed grebes live approximately 10–12 years.[13]
Pied-billed grebes rarely fly. They make a slow dive frequently, especially when in danger, diving to about 20 ft (6.1 m) or less.[3][13] They dive for about 30 seconds and may move to a more secluded area of the water, allowing only the head to be visible to watch the danger dissipate.[13] This frequency in diving has earned them the description of being reclusive or shy in nature.[17] It has also earned them nicknames like "hell-diver."[4] Pied-billed grebes can trap air in their feathers, which controls their buoyancy.[22] They rarely spend time in flocks.[18] Their courtship include calling and sometimes duets.[18] Males will show territorial behaviour if another male is at the edge of his territory. They face each other and then turn their heads and bills up. Then they turn away and start calling. Then they turn back around to look at one another.[13]
The pied-billed grebe breeds in south-central Canada, throughout the United States, Central America, the Caribbean, and temperate South America.[10] These grebes may lay up to two sets of eggs a year.[13] Their nests sit on top of the water, their eggs sitting in vegetation that resides in the water.[17] Grebes lay between three and ten bluish white smooth elliptical eggs with the female starting the incubation process.[3][13] They are incubated for around 23 days by both parents, with the female taking over incubation duties towards the end of that time period.[13][18] They will cover the nest with nesting material if they have to leave it for an extended period of time.[18]
Young grebes may leave the nest within one day of hatching. They are downy at birth. Yellow skin is seen between the lore and top of the head.[13] They do not swim well and stay out of the water. They sleep on their parents' backs. Within four weeks they start swimming.[3] When alerted they will climb on the back of a parent grebe and eventually mature to dive under the water like their parents.[3][17] Both parents share the role of raising the young – both feeding and carrying them on their backs.[18] Sometimes the parents will dive underwater to get food with the chicks on their backs.[13]
Pied-billed grebes feed mainly on aquatic invertebrates, and also on small fish and amphibians (frogs, tadpoles). They dive to obtain food.[3] Their bills allow them to crush crustaceans, like crawfish.[3][18] They may also eat plants.[5] They have been shown to eat their own feathers, like other grebes, to aid in digestion (prevent injury from small bones).[23] They will also feed their feathers to their young.[18]
They are extremely sensitive to disturbances, especially by humans. While breeding, if scared, adults may abandon their nests without protecting the eggs. The waves from boats can destroy the nests and their sounds easily frighten the birds.[12]
Pied-billed grebe feathers are thick and soft. Their feathers were formerly used as decorations on hats and earmuffs and they were hunted in the eastern United States, in the 19th century.[12][13]
The grebes are declining in New England. The reasons are unknown.[18] The states of Connecticut and New Hampshire have declared the pied-billed grebe as endangered. In New Jersey[12] and Massachusetts, they have been declared threatened. In Vermont they are of "special concern." In Rhode Island they are extirpated.[13] Pied-billed grebes are protected under the Migratory Bird Treaty Act of 1918.
Habitat loss is the grebe's biggest threat. The draining, filling, and general destruction of wetlands causes a loss in their breeding habitats.[12] However, they are still common in the majority of their distribution areas.[18]
The pied-billed grebe (Podilymbus podiceps) is a species of the grebe family of water birds. After the extinction of the Atitlán grebe (Podilymbus gigas), the Pied-Billed Grebe became the sole extant member of the genus Podilymbus. The pied-billed grebe is primarily found in ponds throughout the Americas. Other names of this grebe include American dabchick, rail, dabchick, Carolina grebe, devil-diver, dive-dapper, dipper, hell-diver, pied-billed dabchick, pied-bill, thick-billed grebe, and water witch.
