Red-necked grebe (Podiceps grisegena)

Description

What’s the World’s Favourite Species?

Red-necked grebe fact file

• Description
• Biology
• Range
• Habitat
• Status
• Threats
• Conservation
• Find out more
• Glossary
• References
• Print factsheet

Red-necked grebe description

A particularly large grebe, the red-necked grebe (Podiceps grisegena) is a stocky species, with a long neck and a long, straight, robust bill ^{(2) (3)}. The upperparts are dark brownish-black and the wings are dark, with two prominent white patches ⁽²⁾. In breeding plumage, the red-necked grebe has a black cap that extends below the eye, with a slight crest and a large, distinctive pale grey check patch that has whitish margins and extends upward to behind the eye ^{(2) (4)}. The front of the neck and the upper breast are deep chestnut, becoming paler on the belly, while the sides and flanks are greyish.

In non-breeding plumage, the red-necked grebe is somewhat duskier, with a grey-black cap, grey patches on the ear coverts and a white crescent-shaped patch, which curves up from the white chin and throat to behind the ears. The upperparts remain brownish-black, but the striking chestnut colour of the neck is replaced with white or light grey at the front, blending to dark grey-black on the back of the neck ^{(2) (4)}.

Unlike many other grebes, the red-necked grebe has dark irises rather than red, and the bill is black with some yellow at the base ^{(2) (4)}. The legs and feet are black ⁽³⁾. Males are typically larger than females, although the male and female are otherwise similar in appearance. Juvenile red-necked grebes have a brownish-red neck and two prominent diagonal black bands on the sides of the head ^{(2) (5) (6)}. Immature red-necked grebes are similar to the non-breeding adult but have even more grey in the plumage, with some reddish-brown or brown tones on the front of the neck ^{(2) (5)}.

The red-necked grebe has been separated into two subspecies: Podiceps grisegena grisegena, which occurs in Europe and west Asia, and Podiceps grisegena holboelli, which occurs in east Asia and North America. North American and east Asian red-necked grebes are larger than their counterparts in Europe and western Asia, while the European and west Asian grebes have a darker back, cheeks and neck, as well as a less yellow bill ⁽²⁾. 

Size

Length: 43 - 56 cm ⁽²⁾

Weight

0.8 - 1.6 kg ⁽²⁾

Red-necked grebe biology

The diet of the red-necked grebe consists predominantly of invertebrates, such as adult and larval aquatic insects, as well as crayfish, molluscs and some fish ^{(3) (5) (7)}. This species forages primarily in shallow water, diving and pursuing prey underwater, or plucking it off the bottom or off vegetation. The red-necked grebe may also take insects from the water surface or from emergent vegetation, or it may catch low-flying insects from the air ⁽²⁾.

The red-necked grebe usually captures and swallows its prey underwater, although it will often bring larger prey back to the surface. It kills its prey by pinching or shaking it in its bill before manipulating it so that so that it may be swallowed head first ⁽²⁾. 

A strong swimmer and an efficient diver, the red-necked grebe spends the majority of its time on the water. It rarely flies, except during migration to its wintering grounds along the coast ⁽²⁾. This species is territorial during the breeding season, aggressively defending a small territory against other red-necked grebes, and commonly threatening or making underwater attack dives against other intruding birds ^{(2) (5)}. 

The red-necked grebe arrives at its breeding grounds from April. Nest-building begins as soon as pairs have formed, with both male and female red-necked grebes searching for a suitable nest site and contributing to the construction of the nest ⁽²⁾. Generally, the nest is a floating platform of plant matter which has been anchored to vegetation, the lake bottom, or submerged stumps and logs ^{(2) (4) (5) (7)}. The red-necked grebe breeds in isolated pairs from around mid-April to May in Europe and from mid-May to June in North America ⁽⁴⁾. Between 3 and 6 eggs are laid, which are incubated by both adults for a period of 21 to 33 days ^{(2) (3) (4)}.

After hatching, the young chicks climb onto the back of the adult red-necked grebe and are brooded for around ten days. The young are able to dive and explore at around two weeks old and are able to fly after seven to nine weeks. The red-necked grebe chicks continue to be fed by the adults for around 54 days after fledging ^{(2) (4)}.

Red-necked grebe range

The two subspecies of the red-necked grebe have distinct ranges. The North American and east Asian subspecies, Podiceps grisegena holboelli, is found in western Canada and the northwest USA, as well as eastern Russia, northeast China and northern Japan ^{(2) (7)}.

In North America, the red-necked grebe breeds in Alaska, Yukon Territory and the Northwest territories, east to southwest Quebec, and south to Oregon, Idaho, Wyoming, Montana, South Dakota, Minnesota, Wisconsin and southern Ontario. It winters primarily along the Atlantic and Pacific coasts, as well as on the Great Lakes ⁽²⁾. 

The European and west Asian subspecies, Podiceps grisegena grisegena, occurs in Eastern Europe, west and west-central Asia. Wintering populations occur around the North Sea, Black Sea and Caspian Sea ^{(2) (7)}.

Red-necked grebe habitat

Primarily a wetland species ⁽³⁾, the red-necked grebe inhabits a variety of shallow, freshwater lakes or open water in marshy areas. It is also found in secluded bays on larger lakes, ponds, bogs, backwaters and quiet river channels ^{(2) (7)}. The red-necked grebe preferentially breeds on small, shallow, inland waters with abundant emergent vegetation, or on open stretches of water in forested areas ⁽⁷⁾.

Wintering red-necked grebes migrate to coastal or estuarine waters ^{(2) (7)}.

Red-necked grebe status

The red-necked grebe is classified as Least Concern (LC) on the IUCN Red List ⁽¹⁾.

Red-necked grebe threats

The red-necked grebe is threatened by pollutants, which reduce reproductive success by causing egg sterility and eggshell thinning. Habitat degradation and human disturbance are also further threats to the red-necked grebe, particularly at lakes which have been modified for water-based recreational activities ^{(2) (7)}.

Wetland habitat loss due to agriculture, road-building and development, and erosion from overgrazing and cultivation also threaten this species ^{(2) (3)}.

Red-necked grebe conservation

The Red-necked grebe is classified as Endangered in Wisconsin ⁽³⁾.

Recommended conservation measures for the red-necked grebe include a thorough census of the North American population across its breeding range and careful monitoring of breeding populations. Additionally, boat traffic near nesting areas should be minimised to prevent damage to nests and disturbance of incubating or brooding adults. Identifying and protecting key sites away from breeding areas would also benefit the conservation of this species ⁽²⁾.

Further research is also required on the wintering and non-breeding activities of the red-necked grebe ⁽²⁾.

Find out more

Find out more about the red-necked grebe:

• Stout, B. E. and Nuechterlein, G. L. (1999) Red-necked grebe (Podiceps grisegena). In: Poole, A. (Ed.) The Birds of North America Online. Cornell Lab of Ornithology, Ithaca. Available at:
  http://bna.birds.cornell.edu/bna/species/465
• BirdLife International:
  http://www.birdlife.org/datazone/speciesfactsheet.php?id=3638

Authentication

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

Glossary

Coverts

Small feathers concealing the bases of larger flight feathers.

Emergent

Aquatic plants whose stems and leaves extend beyond the water’s surface.

Incubated

To keep eggs warm so that development is possible.

Invertebrates

Animals with no backbone, such as insects, crustaceans, worms, molluscs, spiders, cnidarians (jellyfish, corals, sea anemones), echinoderms, and others.

Larval

Of the stage in an animal’s lifecycle after it hatches from the egg. Larvae are typically very different in appearance to adults; they are able to feed and move around but usually are unable to reproduce.

Molluscs

A diverse group of invertebrates, mainly marine, that have one or all of the following: a horny, toothed ribbon in the mouth (the radula), a shell covering the upper surface of the body, and a mantle or mantle cavity with a type of gill. Includes snails, slugs, shellfish, octopuses and squid.

Subspecies

A population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.

Territory

An area occupied and defended by an animal, a pair of animals or a group.

References

1. IUCN Red List (July, 2011)
   http://www.iucnredlist.org/
2. Stout, B. E. and Nuechterlein, G. L. (1999) Red-necked grebe (Podiceps grisegena). In: Poole, A. (Ed.) The Birds of North America Online. Cornell Lab of Ornithology, Ithaca. Available at:
   http://bna.birds.cornell.edu/bna/species/465
3. Wisconsin Department of Natural Resources - Red-necked grebe (July, 2011)
   http://dnr.wi.gov/org/land/er/biodiversity/index.asp?mode=info&Grp=7&SpecCode=ABNCA03020
4. Polar Conservation Organisation - Red-necked grebe (July, 2011)
   http://www.polarconservation.org/education/arctic-animals/arctic-birds/grebes/red-necked-grebe
5. The Cornell Lab of Ornithology: All About Birds - Red-necked grebe (July, 2011)
   http://www.allaboutbirds.org/guide/Red-necked_Grebe/id  
6. BirdGuides - Red-necked grebe (July, 2011)
   http://www.birdguides.com/species/species.asp?sp=009013
7. BirdLife International - Red-necked grebe (July, 2011)
   http://www.birdlife.org/datazone/speciesfactsheet.php?id=3638