Animal Diversity Web

Ge­o­graphic Range

Bar­row’s gold­eneyes (Bu­cephala is­landica) have a dis­con­tin­u­ous dis­tri­b­u­tion that con­sists of three sep­a­rate pop­u­la­tions. Ap­prox­i­mately 150,000 to 200,000 birds are dis­trib­uted west of the North Amer­i­can Rocky Moun­tains in aquatic habi­tats, from Mon­tana to south­east­ern Alaska. There are smaller sep­a­rated pop­u­la­tions con­sist­ing of ap­prox­i­mately 4,500 birds found in north­east­ern North Amer­ica, from the shores of the Gulf of St. Lawrence, ex­tend­ing down­ward into Maine. Smaller res­i­dent pop­u­la­tions con­sist­ing of 2,000 can also be found in Green­land and Ice­land. Oddly, the east­ern and west­ern pop­u­la­tions show lit­tle vari­a­tion and are seem­ingly iden­ti­cal on the At­lantic and Pa­cific coasts al­though the pop­u­la­tions do not share sim­i­lar bound­aries. (Gar­dars­son, 1978; Robert, et al., 2008)

Win­ter­ing areas for west­ern pop­u­la­tions ex­tend from south­east­ern Alaska to cen­tral Cal­i­for­nia, with most win­ter­ing birds found in the San Fran­cisco Bay and other large open water areas of the north­west­ern states. East­ern pop­u­la­tions can be lo­cal­ized in the Gulf of St. Lawrence and parts of the north­east­ern States. (Robert, et al., 2008)

• Biogeographic Regions
• nearctic
  • native
• palearctic
  • native

• Other Geographic Terms
• holarctic

Habi­tat

Dur­ing the breed­ing sea­son, Bar­row’s gold­eneyes are pri­mar­ily as­so­ci­ated with in­ver­te­brate-rich fresh­wa­ter and al­ka­line lakes that are sur­rounded by ma­ture bo­real forests, where tree cav­i­ties can be found for nest­ing. Al­though un­com­mon, mat­ing Bar­row’s Gold­eneyes can be as­so­ci­ated with sub­alpine lakes, beaver ponds, and small sloughs in west­ern in­ter­moun­tain areas. East­ern pop­u­la­tions of Bar­row’s gold­eneyes pre­fer the same con­di­tions, but can be more as­sorted with small fish­less lakes. (Robert, et al., 2008)

Win­ter­ing Bar­row’s gold­eneyes mi­grate to­wards coastal areas and are mainly found in rocky coastal ma­rine and es­tu­ar­ine habi­tats, in­clud­ing bays, in­lets, har­bors and large, in­te­rior lakes and rivers. Pre­fer­ring shal­lower ice-free wa­ters, strong swim­ming Bar­row’s gold­eneyes for­age in areas with strong cur­rents, but seem to pre­fer slow-flow­ing water. (Robert, et al., 2008)

• Habitat Regions
• polar
• saltwater or marine
• freshwater

• Terrestrial Biomes
• forest

• Aquatic Biomes
• lakes and ponds
• rivers and streams
• coastal

• Other Habitat Features
• estuarine

Phys­i­cal De­scrip­tion

Adult Bar­row’s gold­eneyes are sim­i­lar in ap­pear­ance to com­mon gold­eneyes. They are a chunky-bod­ied, medium-sized div­ing duck, with a large, puffy head and a short neck. Males are slightly larger than fe­males, av­er­ag­ing 48 cm in length, com­pared to 43 cm among fe­males, and weigh 1278 grams, com­pared to 818 grams for fe­males. Breed­ing males have daz­zling plumage, an iri­des­cent pur­plish-black, cres­cent-shaped head, with a sin­gle white patch on each side of the face at the base of the bill and eyes. Their sides, breast, belly, and sec­ondary feath­ers are bright white and their back, wings, and tail are a deep black. These birds also have a se­ries of seven white squares run­ning along the sides of their body. Fe­males have dual-col­ored plumage: with a rich-brown head, grey­ish backs, wings, and tails, and white sides, breasts, and bel­lies. Im­ma­ture or eclipse males re­sem­ble fe­males. Both males and fe­males have a short, tri­an­gu­lar bill. Ma­ture adults of both sexes have bright, deep yel­low irises, hence the com­mon name "gold­en­eye”. Dur­ing flight, their high-speed wings pro­duce a whistling sound. (Gar­rot, 2003)

Bar­row’s gold­eneyes can be con­fused with com­mon gold­eneyes. How­ever, adult male Bar­row’s gold­eneyes have a cres­cent-shaped white patch on the sides of their head, which is oval-shaped in com­mon gold­eneyes, and fewer white sec­ondary feath­ers. Fe­males are more eas­ily con­fused; but fe­male Bar­row’s gold­eneyes have shorter, slop­ing heads and broader bills, which taper abruptly to a nar­rower tip. Hatch­lings of both species are also sim­i­lar in ap­pear­ance. (Gar­rot, 2003)

• Other Physical Features
• endothermic
• homoiothermic
• bilateral symmetry

• Sexual Dimorphism
• male larger
• sexes colored or patterned differently
• male more colorful

• Range mass

  480 to 1320 g

  16.92 to 46.52 oz

• Range length

  43 to 48 cm

  16.93 to 18.90 in

• Range wingspan

  68.58 to 76.2 cm

  27.00 to 30.00 in

Re­pro­duc­tion

They are gen­er­ally monog­a­mous and form pairs while on win­ter­ing grounds. How­ever, male Bar­row’s gold­eneyes can be con­sid­ered polyg­y­nous. Males, also known as drakes, can form si­mul­ta­ne­ous pair bonds with two fe­males. It is sug­gested that polyg­yny in Bar­row's gold­eneyes is not a com­mon breed­ing strat­egy, but is rather an un­usual oc­cur­rence. Males con­duct an as­sort­ment of phys­i­cal dis­plays and vo­cal­iza­tions dur­ing courtship. These dis­plays are sim­i­lar to the dis­plays of com­mon gold­eneyes. Dis­plays in­clude turn­ing their heads and pulling them back at vary­ing speeds, hold­ing their heads up and swing­ing them back­wards with their bills pointed ver­ti­cally, and lift­ing their head up and down with a straight neck. (Savard, 1985)

It is un­known if pair bonds last over mul­ti­ple years, al­though some re­searchers pro­pose Bar­row’s gold­eneyes pair long-term. Forced cop­u­la­tion is com­mon in wa­ter­fowl; how­ever, it has never been doc­u­mented in Bar­row’s gold­eneyes. Drake Bar­row’s gold­eneyes take sev­eral min­utes be­fore mount­ing a prone fe­male; this delay im­plies a strong bond. (Savard, 1985; Savard, 1986)

• Mating System
• monogamous

Bar­row’s gold­eneyes are sec­ondary cav­ity nesters, they use aban­doned nests con­structed by other species, usu­ally ex­ca­vated by pileated wood­peck­ers and north­ern flick­ers. Their nests are hol­lowed out tree cav­i­ties, typ­i­cally white birch. They also ap­pear to rely on the avail­abil­ity of nat­ural cav­i­ties formed in large, de­cay­ing trees for nest­ing. In re­cent decades, nest­ing fe­males have ben­e­fited from man-made nest boxes. Many fe­male Bar­row's gold­eneyes typ­i­cal do not start breed­ing until the age of three years. When fe­males be­come sex­ual ma­ture, they begin to seek out and se­lect suit­able nest sites, ac­com­pa­nied by males. Once cho­sen, the nest is lined with downy feath­ers from the fe­male’s breasts. (Robert, et al., 2010; Savard, 1985)

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

• Breeding interval

  Barrow’s goldeneyes breed yearly, although some individuals do skip occasional years.

• Breeding season

  These birds breed from late May to early April.

• Average eggs per season

  9

• Range time to hatching

  29 to 31 days

• Range fledging age

  8 to 9 weeks

• Range time to independence

  56 to 65 days

• Average age at sexual or reproductive maturity (female)

  3.2 years

• Average age at sexual or reproductive maturity (male)

  2 years

Fe­male Bar­row’s gold­eneyes usu­ally lay a clutch of around 6 to 12 blue-green or olive-green eggs, which are in­cu­bated for 29 to 31 days. Fe­males may leave the nest oc­ca­sion­ally dur­ing the day to for­age. Young Bar­row’s gold­eneyes are well-de­vel­oped at hatch­ing, and are able to leave the nest within the first day. After using their long tails and sharp claws to climb the inner side of the nest cav­ity, young Bar­row’s gold­eneyes must make the long jump from the nest en­trance to the ground, en­cour­aged by the fe­male call­ing to them from below. Young Bar­row’s gold­eneyes have been known to leap from great heights with­out in­jury be­cause of their puffy down feath­ers, which cush­ion their fall. (Robert, et al., 2010)

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

Lifes­pan/Longevity

Bar­row’s gold­eneyes are rather long-lived, with a sin­gle in­di­vid­ual reach­ing 18 years of age. Ac­cord­ing to the USGS, an in­di­vid­ual Bar­row’s gold­en­eye was banded one year after hatch­ing in Alaska in 1965 and killed later in 1979, reach­ing nearly 16 years in age. No ex­ten­sive stud­ies on lifes­pan in cap­tiv­ity have been con­ducted. Sev­eral stud­ies sug­gest that longevity is linked to food avail­abil­ity, sta­ble en­vi­ron­ment, and ab­sence of dis­ease and toxic ma­te­ri­als such as lead and mer­cury. ("Longevity Records Of North Amer­i­can Birds", 2013; Evans, et al., 2002)

• Range lifespan
  Status: captivity

  18 (high) years

• Typical lifespan
  Status: wild

  15 (high) years

Be­hav­ior

Bar­row’s gold­eneyes de­vote their time to preen­ing, swim­ming, div­ing, perch­ing, fly­ing, and for­ag­ing, with most of their time al­lo­cated in the water. Their gross mor­phol­ogy is built for div­ing and swim­ming, how­ever, this hin­ders their abil­ity to be­come air­borne quickly. In­stead of spring­ing straight up out of the water into flight, as pud­dle ducks do, Bar­row’s gold­eneyes must run across the water to build up speed be­fore tak­ing off. Their prin­ci­pal day­time ac­tiv­ity is for­ag­ing, com­pris­ing of most of their time. They typ­i­cally for­age in small groups, div­ing syn­chro­nously to search for prey. Their re­main­ing time con­sists of preen­ing and bathing while on the sur­face of the water or on the shore­line. Mod­er­ately so­cial out­side of the breed­ing sea­son, Bar­row’s gold­eneyes can be ob­served in flocks of 5 to 10 and rarely in flocks of more than 50. How­ever, mi­grat­ing flocks gather with other groups into large flocks at rest sites. It is not un­usual for Bar­row’s gold­eneyes to for­age with dif­fer­ent wa­ter­fowl species. Flight is rapid, with strong wing beats. (Beauchamp, 1992)

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

• Range territory size

  1800 to 14500 m^2

Home Range

Pop­u­la­tions of Bar­row’s gold­eneyes mi­grate be­tween their sum­mer breed­ing ranges and win­ter­ing grounds. They are often one of the last ducks to leave their sum­mer grounds and win­ter as far north as pos­si­ble in ice-free areas. They can be ag­gres­sive and ter­ri­to­r­ial in the spring. Males de­fend ter­ri­tory, and fe­males de­fend the im­me­di­ate area around the nest-site. Paired drakes de­fend ter­ri­to­ries on their breed­ing ponds until mid-in­cu­ba­tion. The size of a breed­ing ter­ri­tory varies de­pend­ing on the lo­ca­tion but it ranges from 0.18 to 1.45 ha. Many fe­male Bar­row's gold­eneyes re­turn to the same breed­ing lo­ca­tions year after year. In some cases, these birds may also de­fend their win­ter ter­ri­to­ries. (Beauchamp, 1992; Eadie, et al., 2014)

Com­mu­ni­ca­tion and Per­cep­tion

Bar­row’s gold­eneyes are mainly silent, ex­cept in courtship when males gives a short "ka-KAA," and near nests, where fe­male makes short soft "cuc" notes. In flight, their wings pro­duce a whistling sound. Vi­sual sig­nals are also used in courtship and ag­gres­sion. (Gar­rot, 2003)

• Communication Channels
• visual
• acoustic

• Perception Channels
• visual
• tactile
• acoustic
• chemical

Food Habits

Bar­row’s gold­eneyes con­sume a va­ri­ety of aquatic or­gan­isms. Their diet con­sists of mus­sels, snails, limpets, crus­taceans, isopods, fish eggs, algae, and vas­cu­lar plants. Their diet likely varies re­gion­ally as well as sea­son­ally. Blue mus­sels are an es­sen­tial food source of Bar­row’s gold­eneyes in the coastal wa­ters of British Co­lum­bia. Dur­ing the spring, fish eggs, such as salmon and her­ring eggs, make up a large por­tion of their diet. Bar­row’s gold­eneyes typ­i­cally hunt for prey in water less than 4 me­ters deep, al­though they may hunt in deeper water. They pre­fer to for­age in open water, al­though they can be fre­quently found along rocky shore­lines in­hab­ited by mus­sels. Prey is swal­lowed while sub­merged under the water. Adults may dive for 10 to 50 sec­onds, while downy young only dab­ble in their first few weeks. In­di­vid­u­als in flocks tend to dive and sur­face in a highly syn­chro­nous fash­ion. Syn­chrony al­lows for groups to main­tain co­he­sion and a watch­ful eye dur­ing for­ag­ing trips. (Beauchamp, 1992; Ver­meer, 1982)

• Primary Diet
• carnivore
  • piscivore
  • eats non-insect arthropods
  • molluscivore
• herbivore
  • granivore
• omnivore

• Animal Foods
• fish
• eggs
• insects
• mollusks
• aquatic crustaceans

• Plant Foods
• roots and tubers

Pre­da­tion

Bar­row’s gold­eneyes re­main sus­cep­ti­ble to an as­sort­ment of preda­tors. Most pre­da­tion oc­curs on nest­ing fe­males and hatch­lings. Preda­tors in­clude Amer­i­can black bears, rac­coons, bald ea­gles, hawks, owls, and weasels such as Amer­i­can martens and fish­ers. Large preda­tory fish, like north­ern pike and muskel­lunges may also prey on more vul­ner­a­ble, im­ma­ture hatch­lings. Non-na­tive Eu­ro­pean star­lings also de­stroy eggs in at­tempts to seize nest cav­i­ties. Young Bar­row’s gold­eneyes often es­cape preda­tors by div­ing un­der­wa­ter. (Evans, et al., 2002)

• Known Predators

  • humans (Homo sapiens)
  • American black bears (Ursus americanus)
  • fishers (Martes pennant)
  • American martens (Martes americanus)
  • raccoons (Procyon lotor)
  • hawks (Accipitridae)
  • owls (Strigiformes)
  • bald eagles (Haliaeetus leucocephalus)
  • northern pike (Esox lucius)
  • muskellunges (Esox masquinongy)
  • American red squirrels (Tamiasciuru hudsonicus)
  • European starlings (Sturnus vulgaris)

Ecosys­tem Roles

Bar­row’s gold­eneyes com­pete for suit­able nest sites with species like com­mon gold­eneyes, buf­fle­heads, squir­rels, north­ern flick­ers, and in­va­sive species like Eu­ro­pean star­lings. Bar­row’s gold­eneyes also com­pete di­rectly with fish for prey and tend to breed and for­age on fish-free lakes. Sim­i­lar to many other duck species, in­traspe­cific nest par­a­sitism is com­mon. Bar­row’s gold­eneyes are par­tic­u­larly noted as brood par­a­sites. Being a brood par­a­site has sev­eral ben­e­fits. The par­a­sitic par­ent does not have to build its own nest, in­cu­bate eggs, or care for chicks. The host fe­male, whose nest is par­a­sitized, ac­cepts in­tro­duced eggs as her own and raises the par­a­site chicks along­side her own brood. Like many ducks, Bar­row’s gold­eneyes are prone to in­fec­tions by a va­ri­ety of par­a­sites. Ex­ter­nal par­a­sites like leeches, lice, bit­ing mos­qui­toes and flies, fleas, mites, and ticks fre­quently in­fest Bar­row’s gold­eneyes. Bar­row’s gold­eneyes are also sus­cep­ti­ble to bot­u­lism and avian cholera. (Ball­we­ber, 2014; Evans, et al., 2002)

• Ecosystem Impact
• disperses seeds

Eco­nomic Im­por­tance for Hu­mans: Pos­i­tive

Bar­row’s gold­eneyes help reg­u­late pop­u­la­tions of prey species in­clud­ing fish, in­sects, mol­lusks, and crus­taceans. This species of duck is also ac­tively tar­geted by sports­man dur­ing fall and win­ter hunt­ing sea­sons. (Robert, et al., 2008)

• Positive Impacts
• food

Eco­nomic Im­por­tance for Hu­mans: Neg­a­tive

There are no known ad­verse ef­fects of Bar­row’s gold­eneyes on hu­mans.

Con­ser­va­tion Sta­tus

Bar­row’s gold­eneyes are pro­tected under the Canada-U.S. Mi­gra­tory Birds Con­ven­tion and are listed as “least con­cern” on the IUCN Red List. How­ever, the Cana­dian Com­mit­tee on the Sta­tus of En­dan­gered Wildlife as­sessed east­ern pop­u­la­tions and con­sid­ers this species as “Spe­cial con­cern.” The provinces of New­found­land and Labrador list east­ern pop­u­la­tions of Bar­row’s gold­eneyes as “Vul­ner­a­ble”. ("BirdLife In­ter­na­tional", 2014; Robert, et al., 2008)

Pop­u­la­tions of Bar­row’s gold­eneyes seem to be rel­a­tively sta­ble. There are sev­eral threats that are ef­fect­ing Bar­row’s gold­eneyes' sur­vival and re­pro­duc­tive suc­cess. Com­mer­cial forestry is likely a sig­nif­i­cant threat to Bar­row’s gold­eneyes but the most dra­matic im­pact on their sur­vival is a loss of habi­tat. Di­rect threats in­clude de­struc­tion of nests dur­ing har­vest op­er­a­tions and a re­duced num­ber of suit­able po­ten­tial nest sites. Hunt­ing also poses a large threat to Bar­row’s gold­eneyes. In­creased dis­tur­bance from hunters can have detri­men­tal con­se­quences if left un­reg­u­lated. Ad­di­tional threats in­clude acid rain, oil spill con­t­a­m­i­na­tion, human dis­tur­bance, and degra­da­tion of food re­sources from oil ex­plo­ration. (Robert, et al., 2008)

• IUCN Red List

  Least Concern

• US Migratory Bird Act

  Protected

• US Federal List

  No special status

• CITES

  No special status

• State of Michigan List

  No special status

Con­trib­u­tors

Michael Kulin­ski (au­thor), North­ern Michi­gan Uni­ver­sity, Alec Lind­say (ed­i­tor), North­ern Michi­gan Uni­ver­sity, Leila Si­cil­iano Mar­tina (ed­i­tor), An­i­mal Di­ver­sity Web Staff.

Ref­er­ences

2014. "BirdLife In­ter­na­tional" (On-line). IUCN Red List of Threat­ened Species. Ac­cessed April 21, 2014 at http://​www.​birdlife.​org.

United States Ge­o­log­i­cal Sur­vey. Longevity Records Of North Amer­i­can Birds. 2013.3. Patux­ent Wildlife Re­search Cen­ter: Jo Anna, Lut­merd­ing. 2013. Ac­cessed April 21, 2014 at http://​www.​pwrc.​usgs.​gov/​.

Ball­we­ber, L. 2014. Wa­ter­fowl par­a­sites. Sem­i­nars in Avian and Ex­otic Pet Med­i­cine, 13/4: 197–205.

Beauchamp, G. 1992. Div­ing Be­hav­ior in Surf Scot­ers and Bar­row's Gold­eneyes. The Auk, Vol. 109, No. 4: 819-827. Ac­cessed Jan­u­ary 21, 2014 at http://​www.​jstor.​org/​stable/​4088156.

Car­ney, S. 1992. Species, age and sex iden­ti­fi­ca­tion of ducks using wing plumage. Wash­ing­ton, DC Jamestown, ND: US De­part­ment of the In­te­rior, US Fish and Wildlife Ser­vice. Ac­cessed Jan­u­ary 22, 2014 at http://​www4.​ncsu.​edu/​~cs­de­pern/doc­u­ments/WaterfowlWings.​pdf.

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Evans, M., D. Lank, W. Boyd, C. Fred. 2002. A Com­par­i­son of the Char­ac­ter­is­tics and Fate of Bar­row's Gold­en­eye and Buf­fle­head Nests in Nest Boxes and Nat­ural Cav­i­ties. The Con­dor, 116/1: 610-619. Ac­cessed March 16, 2014 at http://​dx.​doi.​org/​10.​1650/​0010-5422(2002)104[0610:ACOTCA]2.​0.​CO;2.

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Robert, M., B. Dro­let, J. Savard. 2008. Habi­tat Fea­tures As­so­ci­ated with Bar­row's Gold­en­eye Breed­ing in East­ern Canada. The Wil­son Jour­nal of Or­nithol­ogy, Vol. 120, No. 2: 320-330. Ac­cessed Jan­u­ary 21, 2014 at http://​www.​jstor.​org/​stable/​20456149.

Robert, M., M. Vail­lan­court, P. Dra­peau. 2010. Char­ac­ter­is­tics of nest cav­i­ties of Bar­row's Gold­eneyes in east­ern Canada. Jour­nal of Field Or­nithol­ogy, Vol. 81, No. 3: 287-293. Ac­cessed Jan­u­ary 21, 2014 at http://​www.​jstor.​org/​stable/​3676460.

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van de We­ter­ing, D., F. Cooke. 2000. Body weight and feather growth of male Bar­row's Gold­en­eye dur­ing wing molt. The Con­dor, Vol. 102, No. 1: 228-231. Ac­cessed Jan­u­ary 21, 2014 at http://​www.​bioone.​org/​doi/​full/​10.​1650/​0010-5422%282000%29102%5B0228%3ABWAFGO %5D2.​0.​CO%3B2.