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ruddy turnstone

Arenaria interpres

What do they look like?

Ruddy turnstones are small, robust sandpipers with stout, black, slightly upturned bills. They are 21 to 26 cm long, weighing from 84 and 190 g, and a wingspan of 50 to 57 cm. They look similar in all seasons and males and females look alike. Ruddy turnstones have reddish-brown feathers on their back and wings. They have black and brown feathers on the head and mixed in with the reddish feathers on their backs. The belly is white and the legs are bright orange. They have a dark, black band that stretches across the neck and chest, like a bib.

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    84 to 190 g
    2.96 to 6.70 oz
  • Range length
    21 to 26 cm
    8.27 to 10.24 in
  • Range wingspan
    50 to 57 cm
    19.69 to 22.44 in

Where do they live?

Ruddy turnstones breed far north in arctic tundra from Alaska, across Canada, Greenland, Scandinavia, and northern Siberia to the Bering Sea. In winter they are found along almost all of the coastlines of the world, including North, Central, and South America, Africa, Europe, Asia, Australia, and Pacific Ocean islands.

What kind of habitat do they need?

Ruddy turnstones are found in arctic tundra and rocky coastal areas during the breeding season and along coastlines during winter and migration. Preferred habitats in winter are sandy coastlines and mudflats, but ruddy turnstones are also found on rocky beaches, wetlands, and other intertidal areas. (Nettleship, 2000)

How do they reproduce?

Ruddy turnstones form mated pairs that stay together over many years. Pairs meet again in the same breeding territory used the last year. Ruddy turnstones are fairly aggressive and will even attack their mates at first. Males and females both use flight displays to help attract their mates. Once they are back together, males and females stay within sight of each other until they start incubating the eggs.

Ruddy turnstones arrive on the breeding grounds in late May and early June and mate and begin to lay eggs within 7 to 10 days of their arrival. They create a nest scrape lined with leaves and lichen. Females lay 1 egg each day and usually lay 4 dark brown or olive splotched eggs. Incubation is 21 to 24 days long. Young hatch within a day or two of each other. Fledging occurs at 19 to 21 days old, at which point the young are independent. Ruddy turnstone young remain on their wintering grounds throughout their first year after hatching. Young begin to breed in their 2nd year, although breeding may be delayed until 3 or 4 years old.

  • How often does reproduction occur?
    Ruddy turnstones breed once yearly.
  • Breeding season
    Ruddy turnstones breed in May and June.
  • Range eggs per season
    2 to 5
  • Average eggs per season
  • Range time to hatching
    21 to 24 days
  • Range fledging age
    19 to 21 days
  • Range time to independence
    19 to 21 days
  • Range age at sexual or reproductive maturity (female)
    4 (high) years
  • Average age at sexual or reproductive maturity (female)
    2 years
  • Range age at sexual or reproductive maturity (male)
    4 (high) years
  • Average age at sexual or reproductive maturity (male)
    2 years

Females and males incubate the eggs, but females do most of the incubation and caring for the eggs and nest. Males patrol the nest area and warn the female if there are predators nearby, at which point she will move from the nest to distract attention from the eggs. Young ruddy turnstones hatch with downy feathers and are able to walk and begin to find food within a few hours after hatching and the nest is abandoned within a day of hatching. Males and females protect the hatchlings, but the female abandons them mid-way through the hatchling period and the male remains to protect the young until they fledge, at 19 to 21 days old. Parents aggressively guard their young and lead them to areas with lots of prey, especially midges, so they can feed themselves. A few days after fledging, usually at 21 to 23 days old, the young are almost at adult sizes and begin their first migration to the wintering grounds.

  • Parental Investment
  • precocial
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • male
      • female
  • pre-weaning/fledging
    • protecting
      • male
      • female

How long do they live?

The longest recorded lifespan for ruddy turnstones in the wild is 19.7 years. Average lifespan in Finland was estimated at 6 to 7 years.

  • Range lifespan
    Status: wild
    19.75 (high) years

How do they behave?

Ruddy turnstones are social when they aren't breeding, forming small groups of tens to many thousands and mixing with other species of shorebirds. During the breeding season ruddy turnstones are aggressive and territorial. They are also aggressive outside of the breeding seasons towards other shorebirds competing for food. Ruddy turnstones can fly quickly for long distances, more than 1000 km per day during migration. All ruddy turnstone populations are migratory, traveling great distances across oceans and hemispheres to reach breeding and wintering grounds. Most ruddy turnstones arrive on breeding grounds in May and June and depart for wintering grounds in late July through September, depending on latitude.

Home Range

Ruddy turnstones aggressively defend breeding territories that are from 800 square meters to 1500 hectares in size.

How do they communicate with each other?

Ruddy turnstones use calls and visual displays when communicating with others. They display on the ground and in the air to attract mates. Males call more than females, but both sexes use calls of different kinds. Ruddy turnstones have been described as "noisy." Variations on a call that sounds like "kitititit" are contact and alarm calls. "Pri pri pri" type calls are used to call young. Clicking calls and sounds are used when distracting or attacking predators and high pitched "i i i" sounds are distress calls.

What do they eat?

The ruddy turnstone diet varies seasonally between wintering and breeding habitats. They eat mainly invertebrates, mostly insects, mostly flies and their larvae, during the breeding season and crustaceans, mollusks, and other marine invertebrates during migration and winter.

Ruddy turnstones actively hunt down and efficiently manipulate prey. They use their stout bills to turn over rocks and other objects and probe into sand and soil to find prey. They are skilled at opening and eating bivalves and barnacles.

  • Animal Foods
  • fish
  • eggs
  • carrion
  • insects
  • terrestrial non-insect arthropods
  • mollusks
  • terrestrial worms
  • aquatic or marine worms
  • aquatic crustaceans
  • echinoderms
  • other marine invertebrates
  • Plant Foods
  • fruit

What eats them and how do they avoid being eaten?

Most predation on ruddy turnstones is on eggs and hatchlings. Predators include long-tailed jaegers, parasitic jaegers, glaucous gulls, common ravens, arctic foxes, and red foxes. Many predators take more ruddy turnstone eggs and young when numbers of collared lemmings are low. Ruddy turnstones place their nests far away from others, in order to avoid being found by predators. Males patrol the nesting territory and warn the female when there is a predator nearby. The female will then sneak away from the nest so that the predators can't find it. Parents warn their hatchlings to freeze when they see a predator and the parents may try to distract the predatory by pretending to have a broken wing. Adults are only occasionally preyed on by birds of prey, like Eurasian sparrow-hawks, peregrine falcons, merlins, and owls.

  • These animal colors help protect them
  • cryptic

What roles do they have in the ecosystem?

Ruddy turnstones are predators of insects and other invertebrates in their tundra breeding habitats and crustaceans and mollusks in coastal habitats at other times of the year.

Species (or larger taxonomic groups) that are mutualists with this species
Commensal or parasitic species (or larger taxonomic groups) that use this species as a host

Do they cause problems?

There are no adverse effects of ruddy turnstones on humans.

How do they interact with us?

Ruddy turnstones are fun to watch as they forage along beaches.

Are they endangered?

Ruddy turnstones are not considered threatened because of their large geographic range and population sizes. They are protected under the U.S. Migratory Bird Act. However, populations are threatened by many of the things that threaten shorebirds worldwide: alteration, destruction, and contamination of coastal habitats. Their breeding grounds may also be influenced by global climate change. Especially serious is the effect of coastal disturbance on ruddy turnstones during migration. They rely on places along their migration route where superabundant food resources, such as horseshoe crab eggs (Limulus polyphemus) or herring eggs (Clupea harengus), help them gain fat for the rest of their migration.

Some more information...


Tanya Dewey (author), Animal Diversity Web.



Living in Australia, New Zealand, Tasmania, New Guinea and associated islands.

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living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

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living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map


living in the southern part of the New World. In other words, Central and South America.

World Map


living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map


uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends.


an animal that mainly eats meat


flesh of dead animals.


uses smells or other chemicals to communicate


the nearshore aquatic habitats near a coast, or shoreline.


having a worldwide distribution. Found on all continents (except maybe Antarctica) and in all biogeographic provinces; or in all the major oceans (Atlantic, Indian, and Pacific.


having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

  1. active during the day, 2. lasting for one day.

animals that generate their own body heat through metabolic processes.


an area where a freshwater river meets the ocean and the fresh and saltwater mixes


World Map

Found in northern North America and northern Europe or Asia.


An animal that eats mainly insects or spiders.


offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).


makes seasonal movements between breeding and wintering grounds


eats mollusks, members of Phylum Mollusca


Having one mate at a time.


having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oceanic islands

islands that are not part of continental shelf areas, they are not, and have never been, connected to a continental land mass, most typically these are volcanic islands.


found in the oriental region of the world. In other words, India and southeast Asia.

World Map


reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.


the regions of the earth that surround the north and south poles, from the north pole to 60 degrees north and from the south pole to 60 degrees south.

seasonal breeding

breeding is confined to a particular season


reproduction that includes combining the genetic contribution of two individuals, a male and a female


associates with others of its species; forms social groups.


uses touch to communicate


that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).


Living on the ground.


defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement


the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.


uses sight to communicate

young precocial

young are relatively well-developed when born


Larsen, T. 1991. Antipredator behaviour and mating systems in waders: aggressive nest defence selects for monogamy. Animal Behavior, 41: 1057–1062.

Nettleship, D. 2000. Ruddy turnstone (Arenaria interpres). The Birds of North America Online, 537: 1-20. Accessed April 02, 2009 at

University of Michigan Museum of ZoologyNational Science Foundation

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Dewey, T. 2009. "Arenaria interpres" (On-line), Animal Diversity Web. Accessed April 24, 2014 at

BioKIDS is sponsored in part by the Interagency Education Research Initiative. It is a partnership of the University of Michigan School of Education, University of Michigan Museum of Zoology, and the Detroit Public Schools. This material is based upon work supported by the National Science Foundation under Grant DRL-0628151.
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