The ruddy turnstone is an efficient and opportunistic forager, taking advantage of a wide range of food resources, including insects and insect larvae (particularly midges and other flies during the breeding season), spiders, crustaceans, molluscs, worms and other invertebrates, as well as some plant matter such as berries early in the breeding season. This species will even take small fish and birds’ eggs, and will scavenge on carrion and discarded human food (2) (3) (6) (7). A variety of feeding methods are used, including flipping over objects such as stones and seaweed, probing mud and sand with the beak, digging, or pecking food from the surface of rocks. Despite its small size, the ruddy turnstone is capable of pushing and overturning quite large objects, which are sometimes pushed with the breast (2) (3) (5) (6). Ruddy turnstones often forage in close flocks of up to 100 or more birds, and large flocks may form on migration and during the non-breeding season (2) (3) (6) (7).
The ruddy turnstone breeds from around May to early August, usually in solitary, monogamous pairs. The nest is a shallow scrape on the ground, lined with a small amount of vegetation, and often located on a slight ridge or hummock (2) (3) (5) (6) (7). Up to four eggs are laid and are incubated for around 22 days, mainly by the female but also sporadically by the male. The chicks are able to leave the nest and feed themselves within a day of hatching. Although the adults continue to guard the brood for a time, the female leaves after the first week or two, leaving the male to remain with the young until fledging occurs at around 19 to 21 days (2) (3) (6) (8).
All ruddy turnstones migrate south for the winter months, the females leaving the breeding grounds first, followed by the males and then the newly fledged young (2) (3) (6) (8). Immature birds usually remain in the wintering grounds for the first summer, not breeding until at least two years old (2) (3) (6). Studies have shown that ruddy turnstones can undertake impressive journeys, with some recorded flying 7,600 kilometres non-stop from Australia to Taiwan in just 6 days, before continuing to northern Siberia. One bird even completed a return trip to Australia via the Central Pacific, a total round-trip of 27,000 kilometres (9).