Winter Divers
Written by Menno van Duijn

Divers (or loons, as the Americans call them) can be seen in the Netherlands along the coast or sometimes in large inland lakes in the period September to May. Getting good views is often difficult. Low-light conditions and similar looking plumages make identification even harder. But help is on the way!

To help you with identification issues we picked some videos of swimming and flying birds. Not of birds closeby, but instead we chose videos of distant birds, which are probably a better representation of the views you will get in the field. With every video we give some identification tips. Something on behaviour, good field characters or differences among similar species.

If you miss characters, or find mistakes, please let us know!

How to identify divers from other bird species:

Make sure you are really looking at a diver. When flying or swimming in the distance divers may look quite similar to some other bird species. Think about grebes (all grebes have white patches on the upper wings, divers have none), geese and cormorants (the large diver species have extended feet, white underparts and contrasting neck).

More info about Diver identification can be found in this British Birds article.

Red-throated Diver (Gavia stellata)

This is the most common diver in the Netherlands. It is mainly found on salt water but could be found on lakes and canals too (often birds in poor health conditions). The Red-throated diver is the smallest of the genus and has the whitest look. Birds in flight often put their heads up and down, this a unique character within the genus.

In flight

  • Smallest of all divers but some overlap with Black-throated diver;
  • The whitest of all divers especially in sunny conditions;
  • Extensive white neck, juveniles have however a more smudgier neck;
  • Often in small groups (2-8 birds) and flying at different heights above the water;
  • Only diver that frequently “nods” in flight.

On the water

  • Smallest of all divers;
  • Even from a distance a very white appearance;
  • In adult showing a white spot in front of the eye, making the eye stand out;
  • Head and neck have a 7-like sikhouet, there is not a bulky breast, the neck ends almost vertically at the waterline;
  • Holds thin grey bill upwards;
  • A lot of white in the neck with a narrow grey hind neck, not a a dark “collar”;
  • White flanks with dark lines;
  • Streamlined body, gently sloping to the end.

Black-throated Diver or Arctic Diver (Gavia arctica)

More scarce than Red-throated Diver and more often found on fresh water. Has a darker appearance and can easily be mistaken with juvenile/first winter Red-throated Diver.

In flight

  • A darker and a bit larger diver than Red-throated Diver;
  • Keeps its head more steady than Red-throated Diver, this makes its flight look les nervous;
  • Clear contrast between dark upper and white lower parts.

(no flight video)

On the water

  • Dark diver;
  • Keeps its dagger-like bill level;
  • No dark patch (“collar”) in the neck;
  • Eye in the dark part of the head;
  • Head and neck have a S-like silhouet;
  • More contrasting head and neck, especially between dark hind neck en white front neck. Sometimes only seems to have a white throat and breast;
  • When swimming, white flank under water and hardly visible, except a very clear white flash at the rear at about 3/4th of the body. This white spot is even from a large distance visible. It is a unique character compared to the other diver species.

Great Northern Diver (Gavia immer)

Scarce wintering bird, which occurs both on fresh- and salt water. In the Netherlands it occurs relatively often on large freshwater lakes. The single largest of all divers with an impressive appearance.

In flight

  • Heavily build with low-hanging belly;
  • Strong head and neck;
  • Bill kept horizontal;
  • Has a goose-like flight with strong wing-beats.

On the water;

  • Strong appearance, with a long body;
  • No obvious white flanks;
  • Dark collar patch in the neck;
  • Border between dark hindneck and white front neck is vage. There is no strong contrast between white and dark as in Dark-throated diver;
  • Striking head shape, steep forehead with some kind of protuberance;
  • Head and neck have a Z-like silhouet;
  • Light grey dagger-like bill kept horizontal;
  • Birds lie high on the water.

Yellow-billed Diver (Gavia adamsii)

Very rare winter visitor. Largest of all divers. Confusion is only possible with Great Northern Diver.

  • Looks like Great northern diver but has a “friendlier” appearance;
  • Lives up to it’s name but colour of the bill is sometimes hard to distinguish;
  • A lighter appearance, more milky chocolat compared to GND;
  • Eye better visible on the brighter head than GND, it probably has more white around the eye.;
  • The outer edge of the feathers on the back have a broad light coloured line, the light colured edge is much broader than in Great Northern Diver. This gives a strong scaly pattern;
  • Holds it bill/head in a 45 degrees angle.

Pacific Diver (Gavia pacifica)

Extremely rare in Europe, not yet recorded in the Netherlands. Birds look very similar to Arctic diver. In flight almost impossible to separate from Arctic Diver.

  • Birds on the water show all dark flanks, Pacific divers misses the white rear flash of Arctic diver;
  • Most birds have a thin dark line on the throat, at the edge between throat and neck;
  • Has less contrast between the dark hindneck and white front and cheeck;
  • In good light conditions one can see a three colour tone in the dark parts of the neck;
  • In flight the only feature is a dark line that runs between the legs where Arctic has none: the white undertail coverts are seperated from the white belly by a dark line.