Риђогрли морски гњурац

• Post-breeding molting in the red-throated diver is complete and occurs from late September to December, during which the birds temporarily lose the ability to fly. Primary flight feathers are replaced simultaneously, which is why this happens.
• The red-throated diver is capable of diving to a depth of up to 21 meters. The usual diving depth is 2–9 meters, but in some cases it reaches 21 meters.
• The red-throated diver forages on shallow waters, diving against the current, similar to loons. It often feeds on river shoals.
• The red-throated diver is the smallest of the divers, its mass is 1.1–2.5 kg, and body length is 53–69 cm. It lacks white spots on the back and wings, only small white speckles, which are not visible from a distance.
• The red-throated diver displays an aggressive "penguin stance," rising above the water, stretching its neck upward and raising its beak, while simultaneously slapping its feet against the water. This pose is accompanied by foot slapping, which enhances its visual impact.
• The red-throated diver can live up to 24 years. During wintering and migration in areas with abundant food, birds gather in groups, sometimes numbering up to 500 individuals.
• The red-throated diver is able to take off almost without a run, so it often nests on small ponds with a diameter of 10–15 m. It flies daily to feed on large fish-rich lakes.
• The red-throated diver produces a particularly expressive melodic call "kuuii… kukuii…," characteristic of territorial pairs. At an accelerated tempo, it also performs a unison duet, sounding like a hoarse, trembling "hau-op… hau-op… hau-op.
• The male red-throated diver returns to water immediately after mating, while the female continues to mimic nest-building. After copulation, which lasts 10–20 seconds, the female sometimes extends her neck horizontally, as if building a nest.
• The red-throated diver’s throat patch changes color depending on the distance. From a distance, it appears black and is not a reliable field mark.
• Before copulation, the red-throated diver performs dives and displays a posture lying on water with the necks extended at a 45° angle. Both partners simultaneously dip their bills into the water and dive forcefully, repeating this several times.