Animal Diversity Web

Ge­o­graphic Range

Amer­i­can robins are na­tive to the Nearc­tic re­gion. They occur year-round in south­ern Canada from New­found­land to British Co­lum­bia, through­out most of the United States and along the Sierra Madre into south­ern Mex­ico. They mi­grate south for the win­ter, going as far as south­ern Mex­ico and Guatemala. In sum­mer they are found as far north as north­ern­most Canada and Alaska. Amer­i­can robins are the most abun­dant and wide­spread North Amer­i­can thrush. (Sal­la­banks and James, 1999)

• Biogeographic Regions
• nearctic
  • native

Habi­tat

Amer­i­can robins occur mainly in wood­lands, gar­dens, or­chards, lawns, and fields. They pre­fer areas of open ground or short grass for for­ag­ing, with wood­land or a few scat­tered trees and shrubs nearby for nest­ing and roost­ing. Sub­ur­ban and agri­cul­tural areas often pro­vide these kinds of habi­tats so Amer­i­can robins are com­mon near hu­mans. They need dense shrubs and small trees in which to build their nests. They build nests deep in dense fo­liage to pro­tect their young from preda­tors. (Sal­la­banks and James, 1999)

• Habitat Regions
• temperate
• terrestrial

• Terrestrial Biomes
• forest
• scrub forest

• Other Habitat Features
• urban
• suburban
• agricultural
• riparian

Phys­i­cal De­scrip­tion

Amer­i­can robins are birds that mea­sure 25 cm in length and av­er­age 77 g in weight. Males are only slightly larger than fe­males. They are brown on their backs, red­dish on the breast, and white on their lower belly and under their tail feath­ers. Their throats are white, streaked with black. They have white cres­cents above and below their eyes. Fe­males are slightly paler in color than males. Young Amer­i­can robins have dark spots on their breasts and are also paler in color than adult males. (Sal­la­banks and James, 1999)

• Other Physical Features
• endothermic
• homoiothermic
• bilateral symmetry

• Sexual Dimorphism
• male more colorful

• Average mass

  77 g

  2.71 oz

• Average mass

  75.5 g

  2.66 oz

  AnAge

• Range length

  23 to 28 cm

  9.06 to 11.02 in

• Average length

  25 cm

  9.84 in

• Range wingspan

  119 to 137 mm

  4.69 to 5.39 in

Re­pro­duc­tion

Males and fe­males form a pair bond dur­ing breed­ing sea­son and while rais­ing their young. (Sal­la­banks and James, 1999)

• Mating System
• monogamous

Amer­i­can robins breed in the spring shortly after re­turn­ing to their sum­mer range (north) from their win­ter range (south). The breed­ing sea­son ex­tends from April through July. Amer­i­can robins are one of the first birds to begin lay­ing eggs and nor­mally have two or three sets of young, or broods, in each breed­ing sea­son. The cup-shaped nest is built by the fe­male, who builds the outer foun­da­tion with long coarse grass, twigs, paper, and feath­ers woven to­gether. She lines the inner bowl with mud, smear­ing it with her breast and later adding fine grass or other soft ma­te­r­ial to cush­ion the eggs. The nest can be lo­cated on the ground or high up in trees, but most com­monly 5 to 15 feet above ground in a dense bush, in the crotch of trees, or on win­dow ledges or other human struc­tures. All that is needed for the nest is a firm sup­port and pro­tec­tion from rain. A new nest is built to raise each brood. In north­ern areas the first clutch is gen­er­ally placed in an ever­green tree or shrub, and the later clutches are laid in a de­cid­u­ous tree. From 3 to 5 eggs are laid in each clutch. (Sal­la­banks and James, 1999)

• Key Reproductive Features
• iteroparous
• seasonal breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual
• oviparous

• Breeding interval

  American robins breed once or twice yearly.

• Breeding season

  American robins breed from April to July.

• Range eggs per season

  3 to 5

• Average eggs per season

  4

  AnAge

• Average time to hatching

  14 days

• Average time to hatching

  13 days

  AnAge

• Average fledging age

  13 days

• Average age at sexual or reproductive maturity (female)

  1 years

• Average age at sexual or reproductive maturity (male)

  1 years

Eggs are in­cu­bated by the fe­male. After about 14 days of in­cu­ba­tion the eggs hatch. She con­tin­ues to feed and brood the chicks while they are very young. When the nestlings be­come older the fe­male broods them only at night or dur­ing bad weather. Baby birds leave the nest about 2 weeks after they have hatched. All ba­bies from a clutch leave the nest within 1 day of each other. Even after leav­ing the nest, the young birds fol­low their par­ents and beg food from them. They re­main under cover on the ground dur­ing this time. About two weeks after fledg­ing, young Amer­i­can robins be­come ca­pa­ble of sus­tained flight. (Sal­la­banks and James, 1999)

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

Lifes­pan/Longevity

One wild bird lived to be al­most 14 years old, though most Amer­i­can robins in the wild will live about 2 years. Only about one quar­ter of all young Amer­i­can robins will sur­vive the sum­mer in which they were born. (Sal­la­banks and James, 1999)

• Range lifespan
  Status: wild

  14 (high) years

• Average lifespan
  Status: wild

  2 years

• Average lifespan
  Status: wild

  167 months

  Bird Banding Laboratory

Be­hav­ior

Amer­i­can robins are ac­tive mostly dur­ing the day. They are so­cial birds, es­pe­cially dur­ing the win­ter when they are gath­ered in large num­bers on their win­ter grounds. They as­sem­ble in large flocks at night, often in a se­cluded swamp or area of dense veg­e­ta­tion, where they roost in the trees. These win­ter ag­gre­ga­tions break up dur­ing the day to feed in smaller flocks on fruits and berries. Amer­i­can robins de­fend breed­ing ter­ri­to­ries dur­ing the sum­mer and are less so­cial dur­ing that time. Young Amer­i­can robins re­main in the area of their nest for their first 4 months of life. They gather in mixed-age flocks when it be­comes time to de­part for their win­ter grounds. Al­most all pop­u­la­tions of Amer­i­can robins are mi­gra­tory. (Sal­la­banks and James, 1999)

• Key Behaviors
• flies
• diurnal
• motile
• migratory
• social

Com­mu­ni­ca­tion and Per­cep­tion

Soon after hatch­ing nestlings begin to beg for food by chirp­ing. Adult Amer­i­can robins use chirp­ing or chuck­ing to warn of the pres­ence of a preda­tor. Males begin to sing in the late win­ter and early spring. This song is a fa­mil­iar sound in the spring­time and sounds some­thing like 'cheer­ily, cheer up, cheer up, cheer­ily, cheer up.' Amer­i­can robins sing fre­quently through­out the day, but par­tic­u­larly early in the morn­ing. They most often sing from a perch­ing spot high in a tree. (Sal­la­banks and James, 1999)

• Communication Channels
• visual
• acoustic

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

Amer­i­can Robins feed on a mix­ture of both wild and cul­ti­vated fruits, berries, earth­worms, and in­sects such as bee­tle grubs, cater­pil­lars, and grasshop­pers. Robins are flex­i­ble and will turn to whichever food is most read­ily ac­ces­si­ble, al­though the diet gen­er­ally con­sists of ap­prox­i­mately 40% in­ver­te­brates, 60% fruits and berries. (Sal­la­banks and James, 1999)

• Primary Diet
• omnivore

• Animal Foods
• eggs
• insects
• terrestrial non-insect arthropods
• terrestrial worms

• Plant Foods
• fruit

Pre­da­tion

Amer­i­can robins may mob small preda­tors, such as blue jays and snakes. They also pro­duce chirp­ing and chuck­ing sounds as warn­ing calls.

Preda­tors on young and adults dif­fer some­what. Eggs and young are often eaten by dif­fer­ent types of squir­rels, snakes, and birds such as blue jays, com­mon grack­les, Amer­i­can crows, and com­mon ravens. Adult Amer­i­can robins are preyed upon by hawks, cats, and larger snakes.

Amer­i­can robins are vig­i­lant when feed­ing, they may feed in loose flocks, so that they can also watch other robins for re­ac­tions to preda­tors. (Sal­la­banks and James, 1999)

• Known Predators

  • snakes (Serpentes)
  • hawks (Accipitridae)
  • squirrels (Sciuridae)
  • blue jays (Cyanocitta cristata)
  • common grackles (Quiscalus quiscula)
  • American crows (Corvus brachyrhynchos)
  • common ravens (Corvus corax)
  • domestic cats (Felis silvestris)

Ecosys­tem Roles

Amer­i­can robins are im­por­tant as prey items to their preda­tors be­cause there are so many of them. They also act to con­trol some in­sect pop­u­la­tions and to dis­perse the seeds of the fruits they eat. (Sal­la­banks and James, 1999)

• Ecosystem Impact
• disperses seeds

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Amer­i­can robins are ef­fec­tive in con­trol­ling in­sects that may dam­age crops and gar­dens, such as bee­tles.

• Positive Impacts
• controls pest population

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

Part of the Amer­i­can robin's diet may in­clude berries, which can re­duce the num­ber of berries har­vested every year by cul­ti­va­tors. It has also been re­ported that male Amer­i­can robins have pecked at and dam­aged win­dow­panes, wind­shields, hub­caps, and other pol­ished sur­faces, ap­par­ently re­act­ing to their own re­flec­tions.

• Negative Impacts
• crop pest

Con­ser­va­tion Sta­tus

Amer­i­can robins are suc­cess­ful birds, hav­ing been able to adapt to human al­ter­ation of the land­scape. At one time, they were killed for meat in some south­ern States, and the meat was con­sid­ered a del­i­cacy. They are now pro­tected through­out their range by the U.S. Mi­gra­tory Bird Pro­tec­tion Act.

• IUCN Red List

  Least Concern
  More information

• IUCN Red List

  Least Concern
  More information

• US Migratory Bird Act

  Protected

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Con­trib­u­tors

Tanya Dewey (au­thor, ed­i­tor), An­i­mal Di­ver­sity Web.

Can­dice Mid­dle­brook (au­thor), Uni­ver­sity of Michi­gan-Ann Arbor.

Ref­er­ences

Pough, Richard H. 1946. Audubon Land Bird Guide. Dou­ble­day and Com­pany, New York.

Bur­ton M. and Bru­ton R. 1980. The New Funk and Wag­nalls Il­lus­trated wildlife En­cy­clo­pe­dia, BPC Pub­lish­ing Lim­ited, 1:91-92.

Burke, Ken. 1983. How to At­tract Birds. Orhtho Books, San Fran­cisco.

Sal­la­banks, R., R. James. 1999. Amer­i­can Robin (Tur­dus mi­gra­to­rius). Birds of North Amer­ica, 462: 1-20.