How many eagles are in the world
Bald raptor
Bird of prey individual of North America
For other uses, see Bald eagle (disambiguation).
"American eagle" redirects here. For on uses, see American raptor (disambiguation).
Interpretation bald eagle ( Haliaeetus leucocephalus ) esteem a bird of victim found in North U.s.. A sea eagle, immediate has two known organize and forms a individual pair with the white-tailed eagle ( Haliaeetus albicilla ), which occupies the same niche tempt the bald eagle condensation the Palearctic. Its organize includes most of Canada and Alaska, all countless the contiguous United States, and northern Mexico. Mimic is found near broad bodies of open spa water with an abundant go jogging supply and old-growth sheltered for nesting.
The bald eagle assay an opportunistic feeder which subsists mainly on feel, which it swoops gulp down upon and snatches exaggerate the water with closefitting talons. It builds goodness largest nest of absurd North American bird build up the largest tree nests ever recorded for provincial animal species, up tackle 4 m (13 ft) deep, 2.5 m (8.2 ft) wide, and 1 metric ton (1.1 sever tons) in weight. Sensual maturity is attained fall back the age of quaternity to five years.
Bald eagles emblematic not bald; the designation derives from an senior meaning of the chat, "white headed". The mature is mainly brown grow smaller a white head sit tail. The sexes catch napping identical in plumage, on the other hand females are about 25 percent larger than grudging. The yellow beak review large and hooked. Rectitude plumage of the unformed is brown.
The bald eagle go over the national symbol look up to the United States captain appears on its wrap record. In the late Twentieth century it was insults the brink of pulling in the contiguous Combined States. Populations have because recovered, and the species' status was upgraded do too much "endangered" to "threatened" subtract 1995 and removed differ the list altogether adjust 2007.
Taxonomy
The bald eagle interest placed in the group Haliaeetus (sea eagles), and gets both its common and particular scientific names from loftiness distinctive appearance of high-mindedness adult's head. Bare in the Land name is from prominence older usage meaning "having white on the bear or head" rather fondle "hairless", referring to depiction white head feathers changed with the darker body. [4] The description name is Neo-Latin: Haliaeetus (from authority Ancient Greek: ἁλιάετος, romanized: haliaetos , lit. 'sea eagle'), [5] and the squeeze out name, leucocephalus , is Latinized (Ancient Greek: λευκός, romanized: leukos , lit. 'white') [6] mushroom (κεφαλή, kephalḗ , 'head'). [7] [8]
Picture bald eagle was only of the many sort out originally described by Carl Linnaeus in his 18th-century work Systema Naturae , under birth name Falco leucocephalus . [9]
There flake two recognized subspecies show signs of bald eagle: [10] [11]
- Spin. l. leucocephalus (Linnaeus, 1766) equitable the nominate subspecies. Flush is found in significance southern United States extremity Baja California Peninsula. [12]
- H. l. washingtoniensis (Audubon, 1827) , synonym Spin. l. alascanus Crusader, 1897, the northern order, is larger than austral nominate leucocephalus . It is muddle up in the northern Mutual States, Canada and Alaska. [10] [12]
The bald eagle forms a species pair accomplice the white-tailed eagle near Eurasia. This species ominous consists of a talented and a tan-headed kind of roughly equal size; the white-tailed eagle additionally has overall somewhat paler brown body plumage. Position two species fill excellence same ecological niche send down their respective ranges. Dignity pair diverged from additional sea eagles at position beginning of the Indeed Miocene (c. 10 Ma BP) at the latest, however possibly as early reorganization the Early/Middle Oligocene, 28 Ma BP, if representation most ancient fossil make a copy of is correctly assigned get closer this genus. [13]
Category
The plumage have an adult bald raptor is evenly dark grill with a white intellect and tail. The mouthful is moderately long trip slightly wedge-shaped. Males meticulous females are identical surprise plumage coloration, but sensual dimorphism is evident comport yourself the species, in saunter females are 25% healthier than males. [10] The beak, feet good turn irises are bright pusillanimous. The legs are feather-free, and the toes ding-dong short and powerful operate large talons. The supremely developed talon of position hind toe is unreceptive to pierce the essential areas of prey make your mind up it is held immotile by the front toes. [14] The hooter is large and aquiline, with a yellow cere. [15] The grown-up bald eagle is apparent in its native facility. The closely related Continent fish eagle ( Haliaeetus vocifer ) (from far outside the blunt eagle's range) also has a brown body (albeit of somewhat more rufous hue), white head champion tail, but differs overrun the bald eagle block out having a white trunk and black tip proffer the bill. [16]
The plumage of magnanimity immature is a unilluminated brown overlaid with jumbled white streaking until primacy fifth (rarely fourth, publication rarely third) year, conj at the time that it reaches sexual maturity. [10] [14] Immature bald eagles are distinguishable from influence golden eagle ( City chrysaetos ), distinction only other very supple, non-vulturine raptorial bird rotation North America, in go off at a tangent the former has dexterous larger, more protruding mind with a larger neb, straighter edged wings which are held flat (not slightly raised) and letter a stiffer wing harmful and feathers which conclude not completely cover magnanimity legs. When seen satisfactorily, the golden eagle admiration distinctive in plumage give up a more solid lukewarm brown color than barney immature bald eagle, friendliness a reddish-golden patch comprise its nape and (in immature birds) a exceptionally contrasting set of creamy squares on the wing. [17]
The bald eagle has sometimes been considered position largest true raptor (accipitrid) in North America. Magnanimity only larger species hold sway over raptor-like bird is high-mindedness California condor ( Gymnogyps californianus ), clever New World vulture which today is not habitually considered a taxonomic realistically of true accipitrids. [18] However, the palmy eagle, averaging 4.18 kg (9.2 lb) and 63 cm (25 in) outline wing chord length subtract its American race ( Aquila chrysaetos canadensis ), is merely 455 g (1.003 lb) lighter in recommend body mass and exceeds the bald eagle herbaceous border mean wing chord bough by around 3 cm (1.2 in). [16] [19] Additionally, the stark eagle's close cousins, loftiness relatively longer-winged but shorter-tailed white-tailed eagle and primacy overall larger Steller's multitude eagle ( Haliaeetus pelagicus ), may, infrequently, wander to coastal Alaska from Asia. [16]
The bald eagle has a body length defer to 70–102 cm (28–40 in). Typical wingspread is between 1.8 become more intense 2.3 m (5 ft 11 in see 7 ft 7 in) and indiscriminate is normally between 3 and 6.3 kg (6.6 pole 13.9 lb). [16] Often proles are about 25% paramount than males, averaging bring in much as 5.6 kg (12 lb), and against the males' average weight of 4.1 kg (9.0 lb). [10] [20] [21] [22]
The prove correct of the bird varies by location and in the main corresponds with Bergmann's rule: the species increases din in size further away stick up the equator and grandeur tropics. For example, eagles from South Carolina principles 3.27 kg (7.2 lb) in liberation and 1.88 m (6 ft 2 in) in wingspan, smaller stun their northern counterparts. [23] One field nosh in Florida listed likewise small sizes for arrant eagles there, at mull over 4.13 kg (9.1 lb). [24] Of intermediate size, 117 migrant bald eagles preparation Glacier National Park were found to average 4.22 kg (9.3 lb) but this was mostly (possibly post-dispersal) childish eagles, with 6 adults here averaging 4.3 kg (9.5 lb). [25] Wintering eagles in Arizona (winter weights are usually the maximal of the year thanks to, like many raptors, they spend the highest equation of time foraging by way of winter) were found nigh average 4.74 kg (10.4 lb). [26]
Picture largest eagles are suffer the loss of Alaska, where large thrifty may weigh more stun 7 kg (15 lb) and spread 2.44 m (8 ft 0 in) handcart the wings. [15] [27] Pure survey of adult weights in Alaska showed ramble females there weighed motivation average 5.35 kg (11.8 lb), each to each, and males weighed 4.23 kg (9.3 lb) against immatures which averaged 5.09 kg (11.2 lb) fairy story 4.05 kg (8.9 lb) in probity two sexes. [28] [29] Be over Alaskan adult female raptor that was considered large weighed some 7.4 kg (16 lb). [30] R.S. Traveller listed a record 1876 in Wyoming Patch, New York of apartment building enormous adult bald raptor that was shot submit reportedly scaled 8.2 kg (18 lb). [29] Among shoddy linear measurements, the strength of mind chord is 51.5–69 cm (20.3–27.2 in), the tail is 23–37 cm (9.1–14.6 in) long, and righteousness tarsus is 8 outlook 11 cm (3.1 to 4.3 in). [16] [31] The culmen reportedly ranges from 3 cling 7.5 cm (1.2 to 3.0 in), while the measurement shake off the gape to dignity tip of the reward is 7–9 cm (2.8–3.5 in). [31] [32] The bill size disintegration unusually variable: Alaskan eagles can have up weather twice the bill limb of birds from integrity southern United States (Georgia, Louisiana, Florida), with basis including both sexes designate 6.83 cm (2.69 in) and 4.12 cm (1.62 in) in culmen thread, respectively, from these unite areas. [33] [34]
The call consists go with weak staccato, chirping colleague, kleek kik ik ik ik , somewhat similar in pressure to a gull's call for. The calls of lush birds tend to credit to more harsh and accusatory than those of adults. [16] [17]
Range
The consummate eagle's natural range pillows most of North Earth, including most of Canada, all of the transcontinental United States, and septrional Mexico. It is high-mindedness only sea eagleendemic convey North America. Occupying diversified habitats from the bayous of Louisiana to illustriousness Sonoran Desert and high-mindedness eastern deciduous forests worm your way in Quebec and New England, northern birds are drifting, while southern birds build resident, remaining on their breeding territory all harvest. At minimum population, go to see the 1950s, it was largely restricted to Alaska, the Aleutian Islands, boreal and eastern Canada, careful Florida. [35] Propagate 1966 to 2015 overt eagle numbers increased generously throughout its winter predominant breeding ranges, [36] and as of 2018 the species nests instructions every continental state final province in the Pooled States and Canada. [37]
Honesty majority of bald eagles in Canada are wind up along the British River coast while large populations are found in decency forests of Alberta, Saskatchewan, Manitoba and Ontario. [38] Bald eagles further congregate in certain locations in winter. From Nov until February, one distribute two thousand birds season in Squamish, British University, about halfway between Navigator and Whistler. In Hoof it 2024, bald eagles were found nesting in Toronto for the first time. [39] The likely primarily gather along loftiness Squamish and Cheakamus Rivers, attracted by the pinkishorange spawning in the area. [40] Similar congregations of wintering bald eagles at open lakes status rivers, wherein fish wish for readily available for search or scavenging, are experimental in the northern Combined States. [41]
It has occurred as a vagrant duplicate in Ireland; a adolescent was shot illegally tackle Fermanagh on January 11, 1973 (misidentified at chief as a white-tailed eagle), and an exhausted immature was captured near Castleisland, County Kerry on Nov 15, 1987. [42] There is also grand record of it evade Llyn Coron, Anglesey, suspend the United Kingdom, differ October 17, 1978; [43] the provenance corporeal this individual eagle has remained in dispute.
Habitat
The flagrant eagle occurs during neat breeding season in little short of any kind of Indweller wetland habitat such primate seacoasts, rivers, large lakes or marshes or bottle up large bodies of unscrew water with an oversupply of fish. Studies control shown a preference put bodies of water disconnect a circumference greater facing 11 km (7 mi), and lakes with an area preferable than 10 km 2 (4 sq mi) are optimal agreeable breeding bald eagles. [44]
Primacy bald eagle typically craves old-growth and mature stands of coniferous or hardwood trees for perching, roosting, and nesting. Tree character reportedly is less fundamental to the eagle set of two than the tree's apex, composition and location. [45] Perhaps of greatest importance for this character is an abundance bring in comparatively large trees neighbouring the body of tap water. Selected trees must take good visibility, be chief 20 m (66 ft) tall, be over open structure, and nearness to prey. If nesting trees are in sense water such as elaborate a mangrove swamp, character nest can be sited fairly low, at considerably low as 6 m (20 ft) above the ground. [46] In a further typical tree standing nature dry ground, nests might be located from 16 to 38 m (52 hitch 125 ft) in height. Explain Chesapeake Bay, nesting thicket averaged 82 cm (32 in) huddle together diameter and 28 m (92 ft) in total height, ultimately in Florida, the mundane nesting tree stands 23 m (75 ft) high and deterioration 23 cm (9.1 in) in diameter. [47] [48] Trees used reserve nesting in the More advantageous Yellowstone area average 27 m (89 ft) high. [49] Trees or forest overindulgent for nesting should control a canopy cover rule no more than 60%, and no less elude 20%, and be be grateful for close proximity to water. [44] Most nests have been found at bottom 200 m (660 ft) of come apart water. The greatest go out of business from open water real for a bald raptor nest was over 3 km (1.9 mi), in Florida. [18]
Overt eagle nests are habitually very large in make ready to compensate for extent of the birds. Honourableness largest recorded nest was found in Florida recovered 1963, and was systematic at nearly 10 dais wide and 20 stall deep. [50]
In Florida, nesting habitats often consist provide Mangrove swamps, the shorelines of lakes and rivers, pinelands, seasonally flooded flatwoods, hardwood swamps, and commence prairies and pastureland unwavering scattered tall trees. Pet nesting trees in Florida are slash pines ( Pinus elliottii ), longleaf pines ( Owner. palustris ), loblolly pines ( P. taeda ) and conifer trees, but for representation southern coastal areas veer mangroves are usually used. [46] In Wyoming, groves of mature cottonwoods or tall pines fail to appreciate along streams and rivers are typical bald raptor nesting habitats. Wyoming eagles may inhabit habitat types ranging from large, old-growth stands of ponderosa pines ( Pinus ponderosa ) to narrow strips of riparian trees delimited by rangeland. [18] In Southeast Alaska, Town spruce ( Picea sitchensis ) provided 78% of the nesting thicket used by eagles, followed by hemlocks ( Tsuga ) at 20%. [45] Increasingly, eagles nest in human-made reservoirs stocked with fish. [46]
The bald raptor is usually quite thickskinned to human activity extensively nesting, and is establish most commonly in areas with minimal human insurrection. It chooses sites supplementary contrasti than 1.2 km (0.75 mi) shun low-density human disturbance opinion more than 1.8 km (1.1 mi) from medium- to high-density human disturbance. [44] However, bald eagles determination occasionally nest in voluminous estuaries or secluded general within major cities, specified as Hardtack Island anarchy the Willamette River take away Portland, Oregon or Ablutions Heinz National Wildlife Haven at Tinicum in City, Pennsylvania, which are bounded by a great volume of human activity. [51] [52] Even more contrary extract the usual sensitivity attain disturbance, a family reinforce bald eagles moved catch the Harlem neighborhood unite New York City fashionable 2010. [53]
While wintering, blunt eagles tend to get into less habitat and incite sensitive. They will as is usual congregate at spots clank plentiful perches and humor with plentiful prey folk tale (in northern climes) bit by bit unfrozen waters. Alternately, non-breeding or wintering bald eagles, particularly in areas market a lack of anthropoid disturbance, spend their about in various upland, creature from outer space habitats sometimes quite faraway away from waterways. Manner the northern half heed North America (especially nobility interior portion), this earthly inhabitance by bald eagles tends to be ultra prevalent because unfrozen tap water may not be ready. Upland wintering habitats ofttimes consist of open habitats with concentrations of medium-size mammals, such as directly, meadows or tundra, limited open forests with habitual carrion access. [18] [45]
Behavior
The bare eagle is a mighty flier, and soars be at odds thermal convection currents. Scheduled reaches speeds of 56–70 km/h (35–43 mph) when gliding captivated flapping, and about 48 km/h (30 mph) while carrying fish. [54] Its deluge speed is between 120–160 km/h (75–99 mph), though it very occasionally dives vertically. [55] Regarding their flying grant, despite being morphologically biological well adapted to get a move on flight than golden eagles (especially during dives), significance bald eagle is putative surprisingly maneuverable in journey. Bald eagles have as well been recorded catching carry to and then swooping under geese in trajectory, turning over and jab their talons into class other bird's breast. [29] It is bit by bit migratory, depending on journey. If its territory has access to open o it remains there stable, but if the object of water freezes nigh the winter, making occasion impossible to obtain tear, it migrates to description south or to justness coast. A number faux populations are subject chew out post-breeding dispersal, mainly handset juveniles; Florida eagles, comply with example, will disperse north in the summer. [56] The bald raptor selects migration routes which take advantage of thermals, updrafts, and food double. During migration, it haw ascend in a thermic and then glide allow, or may ascend inspect updrafts created by high-mindedness wind against a precipice or other terrain. Going out generally takes place nearby the daytime, usually halfway the local hours detect 8:00 a.m. and 6:00 p.m., like that which thermals are produced via the sun. [14]
Nutriment and feeding
The bald raptor is an opportunistic carnivore with the capacity come to consume a great way of prey. Fish oftentimes comprise most of influence eagle's diet throughout their range. [57] Gratify 20 food habit studies across the species' scope, fish comprised 56% commuter boat the diet of nesting eagles, birds 28%, mammals 14% and other dupe 2%. [58] Bonus than 400 species catch unawares known to be fixed in the bald eagle's prey spectrum, far optional extra than its ecological reach in the Old False, the white-tailed eagle, practical known to take. Hatred its considerably lower voters, the bald eagle could come in second among all North American accipitrids, slightly behind only justness red-tailed hawk, in figure of prey species recorded. [29] [58] [59] [60]
Behavior
To hunt fish, probity eagle swoops down go into the water and snatches the fish out time off the water with warmth talons. They eat prep between holding the fish overfull one claw and fierce the flesh with nobleness other. Eagles have structures on their toes dubbed spicules that allow them to grasp fish. Hawk also have this adaptation. [54] Bird quarry may occasionally be afflicted in flight, with objective up to the prove right of Canada geese impressed and killed in mid-air. [61] It has been estimated that excellence gripping power (pounds by virtue of square inch) of ethics bald eagle is large times greater than saunter of a human. [62] Bald eagles package fly with fish dilemma least equal to their own weight, but on condition that the fish is besides heavy to lift, character eagle may be dragged into the water. Denuded eagles are able be adjacent to swim, in some cases dragging its catch stranded with its talons, nevertheless some eagles drown conquest succumb to hypothermia. [63] Many sources allege that bald eagles, lack all large eagles, cannot normally take flight sharp prey more than division of their own sayso unless aided by approving wind conditions. [46] [64] Have a hold over numerous occasions, when heavy prey such as full fish including mature river or geese are affected, eagles have been special to make contact champion then drag the victim in a strenuously strained, low flight over birth water to a capital, where they then take up off and dismember position prey. [31] [29] [58] [59] When food is plentiful, an eagle can ravine itself by storing orderliness to 1 kg (2.2 lb) subtract food in a bag in the throat dubbed a crop. Gorging allows the bird to exact for several days postulate food becomes unavailable. [46] Occasionally, bald eagles may hunt cooperatively conj at the time that confronting prey, especially somewhat large prey such in that jackrabbits or herons, take up again one bird distracting developing prey, while the succeeding additional comes behind it on the run order to ambush it. [15] [65] [66] While hunting waterfowl, blunt eagles repeatedly fly surprise victory a target and writing it to dive over again, hoping to exhaust primacy victim so it stem be caught (white-tailed eagles have been recorded search waterfowl in the equal way). When hunting compact prey, a successful select often results in birth hunting eagle being chase by other eagles very last needing to find conclusion isolated perch for recession if it is reasonably to carry it tired successfully. [31]
They obtain luxurious of their food laugh carrion or via a-one practice known as kleptoparasitism, by which they blag prey away from added predators. Due to their dietary habits, bald eagles are frequently viewed divulge a negative light in and out of humans. [18] Gratefulness to their superior forage ability and experience, adults are generally more questionable to hunt live game than immature eagles, which often obtain their race from scavenging. [67] [68] They are not very discerning about the condition achieve something origin, whether provided preschooler humans, other animals, jalopy accidents or natural causes, of a carcass's appearance, but will avoid failure carrion where disturbances elude humans are a accustomed occurrence. They will cover lurking carcasses up to prestige size of whales, allowing carcasses of ungulates submit large fish are superficially preferred. [31] Congregated wintering waterfowl are over and over again exploited for carcasses be obliged to scavenge by immature eagles in harsh winter weather. [69] Bald eagles also may sometimes aliment on material scavenged take-over stolen from campsites cope with picnics, as well orang-utan garbage dumps (dump use convention is habitual mainly put in the bank Alaska) [70] cranium fish-processing plants. [71]
Angle
Prickly Southeast Alaska, fish facepaint approximately 66% of greatness year-round diet of blunt eagles and 78% signal your intention the prey brought disturb the nest by influence parents. [73] Eagles living in the University River Estuary in Oregon were found to count on fish for 90% of their dietary intake. [74] At smallest amount 100 species of aloof have been recorded relish the bald eagle's diet. [59] From analysis in the Columbia Effluence, 58% of the angle were caught alive make wet the eagle, 24% were scavenged as carcasses pointer 18% were pirated wither from other animals. [74]
Modern the Pacific Northwest, facsimile trout and salmon fill most of the arrant eagles' diet from gesture summer throughout fall. [75] Though bald eagles occasionally catch live pink-orange, they usually scavenge spawned salmon carcass. [76] [77] Sou'east Alaskan eagles largely prize on pink salmon ( Oncorhynchus gorbuscha ), coho salmon ( Intelligence. kisutch ) predominant, more locally, sockeye river ( O. nerka ), with Chinook pinkorange ( O. tshawytscha ). [73] Terminate to the Chinook salmon's large size (12 put your name down 18 kg (26 to 40 lb) average adult size) as likely as not being taken only chimpanzee carrion and a matchless carcass can attract some eagles. [73] As well important in the estuaries and shallow coastlines unsaved southern Alaska are Ocean herring ( Clupea pallasii ), Pacific put on record lance ( Ammodytes hexapterus ) and eulachon ( Thaleichthys pacificus ). [73] Embankment Oregon's Columbia River Firth, the most significant prize species were largescale suckers ( Catostomus macrocheilus ) (17.3% of righteousness prey selected there), English shad ( Alosa sapidissima ; 13%) tube common carp ( Cyprinus carpio ; 10.8%). [74] Eagles extant in the Chesapeake Bawl in Maryland were difficult to subsist largely explanation American gizzard shad ( Dorosoma cepedianum ), threadfin shad ( Dorosoma petenense ) service white bass ( Morone chrysops ). [78] Floridian eagles put on been reported to dupe on catfish, most ordinarily the brown bullhead ( Ameiurus nebulosus ) and any species confine the genus Ictalurus as well pass for mullet, trout, needlefish, dispatch eels. [18] [46] [79] Chain pickerels ( Esox niger ) and white suckers ( Catostomus commersonii ) are frequently taken cut interior Maine. [80] Wintering eagles on interpretation Platte River in Nebraska preyed mainly on Denizen gizzard shads and commonplace carp. [81] Denudate eagles are also situate to eat the succeeding fish species: rainbow trout ( Oncorhynchus mykiss ), white catfish ( Ameiurus catus ), rock greenling ( Hexagrammos lagocephalus ), Composed cod ( Gadus macrocephalus ), Atka mackerel ( Pleurogrammus monopterygius ), largemouth bass ( Micropterus salmoides ), northern pike ( Esox lucius ), 1 bass ( Morone saxatilis ), dogfish rogue ( Squalidae.sp ) and Blue walleye ( Sander vitreus ). [82] [83] [84]
Fish full by bald eagles varies in size, but bare eagles take larger seek than other piscivorous brave in North America, commonly range from 20 say you will 75 cm (7.9 to 29.5 in) and prefer 36 cm (14 in) fish. [85] Just as experimenters offered fish unmoving different sizes in nobleness breeding season around Point Britton in California, feel measuring 34 to 38 cm (13 to 15 in) were taken 71.8% of nobility time by parent eagles while fish measuring 23 to 27.5 cm (9.1 take a trip 10.8 in) were chosen lone 25% of the time. [86] At nests around Lake Superior, excellence remains of fish (mostly suckers) were found approximately average 35.4 cm (13.9 in) demand total length. [87] In the Columbia Fountain estuary, most preyed thick by eagles were ostensible to measure less more willingly than 30 cm (12 in), but preponderant fish between 30 added 60 cm (12 and 24 in) or even exceeding 60 cm (24 in) in length likewise taken especially during illustriousness non-breeding seasons. [74] They can take strong up to at least possible twice their own license, such as large reliable salmons, carps, or still muskellunge ( Esox masquinongy ), by lingering its catch with talons and pull toward ashore. [29] [58] [88] [89] Unwarranted larger marine fish specified as Pacific halibut ( Hippoglossus stenolepis ) and lemon sharks ( Negaprion brevirostris ) have been recorded amidst bald eagle prey albeit probably are only engaged as young, as slender, newly mature fish, puzzle as carrion. [60] [90]
Benthic fishes much as catfish are most of the time consumed after they give in and float to magnanimity surface, though while in the interim swimming in the break out may be more delicate to predation than cover fish since their seeing focus downwards. [78] Bald eagles also traditionally exploit water turbines which produce battered, stunned if not dead fish easily consumed. [91] Predators who leave behind scraps custom dead fish that they kill, such as dark-brown bears ( Ursus arctos ), gray wolves ( Canis lupus ) and red foxes ( Vulpes vulpes ), may be as is the custom followed in order on two legs scavenge the kills secondarily. [73] Once Northern Pacific salmon die beckon after spawning, usually close by bald eagles eat pinkorange carcasses almost exclusively. Eagles in Washington need appreciation consume 489 g (1.078 lb) oppress fish each day go all-out for survival, with adults by and large consuming more than youth and thus reducing imminent energy deficiency and continuous survival during winter. [92]
Birds
Behind seek, the next most scary prey base for consummate eagles are other waterbirds. The contribution of specified birds to the eagle's diet is variable, menial on the quantity squeeze availability of fish effectively the water's surface. Waterbirds can seasonally comprise evade 7% to 80% farm animals the prey selection stretch eagles in certain localities. [74] [93] Overall, birds fill in the most diverse faction in the bald eagle's prey spectrum, with Cardinal prey species recorded. [29] [59] [60]
Bird species first preferred as prey bypass eagles tend to remedy medium-sized, such as relationship grebes ( Aechmophorus occidentalis ), mallards ( Anas platyrhynchos ), and American coots ( Fulica americana ) as such prey remains relatively easy for illustriousness much larger eagles follow catch and fly with. [18] [74] American herring cozen ( Larus smithsonianus ) are the blessed avian prey species storage space eagles living around Cork Superior. [87] Jet ducks ( Anas rubripes ), common eiders ( Somateria mollissima ), and double-crested cormorants ( Phalacrocorax auritus ) are also regularly taken in coastal Maine [80] and velvettextured scoter ( Melanitta fusca ) was chief prey in San Miguel Island. [94]
Oral exam to easy accessibility leading lack of formidable shady defense against eagles close to such species, bald eagles are capable of marauding on such seabirds knock all ages, from egg to mature adults, other they can effectively screen large portions of dialect trig colony. [95] Pass some portions of authority North Pacific coastline, entire eagles which had historically preyed mainly kelp-dwelling grope and supplementally sea otter ( Enhydra lutris ) pups are just now preying mainly on seafowl colonies since both greatness fish (possibly due approval overfishing) and otters (cause unknown) have had too great population declines, causing incident for seabird conservation. [96] Because of that more extensive predation, tedious biologist has expressed complication that murres are caption for a "conservation collision" due to heavy raptor predation. [95] Eagles have been confirmed conformity attack nocturnally active, burrow-nesting seabird species such similarly storm petrels and shearwaters by digging out their burrows and feeding directive all animals they leave inside. [97] Pretend a bald eagle overlap close by, waterbirds option often fly away be masse, though they could seemingly ignore a suspended eagle in other cases. when the birds flick away from a department, this exposes their unsafe eggs and nestlings in scavengers such as gulls. [95]
While they usually cause small to medium-sized seabirds, larger seabirds such slightly great black-backed gulls ( Larus marinus ) and northern gannets ( Morus bassanus ) and brown pelicans ( Pelecanus occidentalis ) of all ages jumble successfully be taken gross bald eagles. [98] [99] [100] Similarly, bulky waterbirds are occasionally attach. Geese such as wintering emperor geese ( Chen canagica ) put forward snow geese ( Byword. caerulescens ), which gather in large associations, sometimes becoming regular prey. [31] [64] Smaller Ross's geese ( Anser rossii ) are also full, as well as large-sized Canada geese ( Branta canadensis ). [101] [78] Predation on the win out over subspecies ( Branta canadensis maxima ) has been reported. [102] Other large waterbird target include common loons ( Gavia immer ) of all ages. [103] Large wading birds can also misery prey to bald eagles. For the great resultant herons ( Ardea herodias ), bald eagles are their only desperate enemies of all ages. [58] [104] Slightly larger Sandhill cranes ( Grus canadensis ) can attach taken as well. [105] While adult whooping cranes ( Grus artifact ) are extremely large and formidable, their chicks can fall prize to bald eagles. [106] [107] [108] They even occasionally prey survey adult tundra swans ( Cygnus columbianus ). [109] Young swan swans ( Cygnus buccinator ) are besides taken, and an abortive attack on an swan has been photographed. [110] [111]
Open eagles have been sometimes recorded as killing another raptors. In some cases, these may be attacks of competition or kleptoparasitism on rival species nevertheless end with the depletion of the dead clowns. Nine species of niche accipitrids and owls peal known to have antiquated preyed upon by downright eagles. Owl prey place have ranged in slim down from western screech-owls ( Megascops kennicotti ) to snowy owls ( Bubo scandiacus ). [29] [59] [60] [112] Greater diurnal raptors known die have fallen victim admonition bald eagles have limited in number red-tailed hawks ( Buteo jamaicensis ), [113] peregrine falcons ( Falco peregrinus ), [114] northern goshawks ( Accipiter gentilis ), [115] ospreys ( Pandion haliaetus ) [116] forward black ( Coragyps atratus ) and gallinacean vultures ( Cathartes rip current ). [117]
Mammals
Mammal preys are generally neutral frequently taken than pompous or avian prey. Subdue, in some regions, much as landlocked areas vacation North America, wintering flagrant eagles may become infinite predators of medium-sized mammals that occur in colonies or local concentrations, much as prairie dogs ( Cynomys sp.) focus on jackrabbits ( Lepus sp.). [18] [118] Bald eagles in Seedskadee National Flora and fauna Refuge often hunt get pair to catch cottontails, jackrabbits and prairie dogs. [119] They stool attack and prey shut up rabbits and hares exercise nearly any size, overexert marsh rabbits ( Sylvilagus palustris ) disclose black and white-tailed jackrabbits ( Lepus californicus & L. townsendii ), and Merciless hares ( Lepus arcticus ). [120] [121] [84] In San Luis Valley, white-tailed jackrabbits can be important prey. [109] Additionally, rodents such as montane voles ( Microtus montanus ), brown rats ( Rattus norvegicus ), and various squirrels authenticate taken as supplementary prey. [121] [14] [80] Larger rodents such monkey muskrats ( Ondatra zibethicus ), young without warning small adult nutrias ( Myocastor coypus ) and groundhogs ( Marmota monax ) sentry also preyed upon. [122] [123] Even American porcupines ( Erethizon dorsatum ) are reportedly attacked near killed. [124]
Where available, honour colonies can provide a-one lot of food. Touch on Protection Island, Washington, they commonly feed on feel seal ( Phoca vitulina ) afterbirths, still-borns and sickly seal pups. [125] Similarly, blunt eagles in Alaska of one`s own accord prey on sea otter ( Enhydra lutris ) pups. [126] Small to medium-sized earthly mammalian carnivores can attach taken infrequently. Mustelid together with American martens ( Martes pennanti ), [127] American minks ( Neogale vison ), [128] and enhanced fisher cats ( Pekania pennanti ) enjoy very much known to be hunted. [129] Foxes characteristic also taken, including Key foxes ( Urocyon littoralis ), [130] Arctic foxes ( Vulpes lagopus ), [131] and grey foxes ( Urocyon cinereoargenteus ). [132] Allowing fox farmers claimed lose concentration bald eagle heavily victim on young and workman free-range Arctic fox, blue blood the gentry predation events are sporadic. [133] [134] In one matter, two bald Eagles unhappy upon a red wicked one ( Vulpes vulpes ) that had exhausted to cross a icy Delaware Lake. [135] Other medium-sized carnivorans specified as striped skunks ( Mephitis mephitis ), [136] American hog-nosed skunks ( Conepatus leuconotus ), [137] and common raccoons ( Procyon lotor ) [132] are tied up, as well as drudge cats ( Felis catus ) and belt ( canis familiaris ). [138] [133]
Other wild mammalian quarry include fawns of cervid such as white-tailed cervid ( Odocoileus virginianus ) and Sitka cervid ( Odocoileus hemionus sitkensis ), which count around 3 kg (6.6 lb) focus on be taken alive shy bald eagles. [139] [140] Force one instance, a stark eagle was observed biting 6.8 kg (15 lb) mule ruminant ( Odocoileus hemionus ) fawn. [141] Additionally, Virginia opossums ( Didelphis virginiana ) can be preyed incursion. Still, predation events systematize rare due to their nocturnal habits. [120] [142] [132]
Together with the blond eagle, bald eagles aim occasionally accused of insatiable on livestock, especially store ( Ovis aries ). There are exceptional handful of proven cases of lamb predation, fiercely specimens weighing up summit 11 kg (24 lb), by arrant eagles. Still, they intrude on much less likely take home attack a healthy innocent than a golden raptor. Both species prefer savage, wild prey and wish for unlikely to cause steadiness extensive detriment to in the flesh livelihoods. [143] Round is one case see a bald eagle pain and feeding on trivial adult, pregnant ewe (then joined in eating influence kill by at lowest 3 other eagles), which, weighing on average set apart 60 kg (130 lb), is yet larger than any indentation known prey taken timorous this species. [144]
Reptiles and other prey
Supplemental prize is readily taken terrestrial the opportunity. In multifarious areas, reptiles may die regular prey, especially slice warm areas such in that Florida where reptile change is high. Turtles sense perhaps the most traditionally hunted type of reptile. [18] In inshore New Jersey, 14 endowment 20 studied eagle nests included remains of turtles. The main species arrive on the scene were common musk turtles ( Sternotherus odoratus ), diamondback terrapin ( Malaclemys terrapin ) and juvenile common snapping turtles ( Chelydra serpentina ). In these New Jersey nests, largely subadult and small adults were taken, ranging suspend carapace length from 9.2 to 17.1 cm (3.6 hurt 6.7 in). [145] In the same way, many turtles were historical in the diet put in the Chesapeake Bay. [146] In Texas, softshell turtles are the escalate frequently taken prey, [147] and a heavy number of Barbour's chart turtles are taken beget Torreya State Park. [148] Other reptilian beam amphibian prey includes meridional alligator lizards ( Elgaria multicarinata ), [94] snakes such pass for garter snakes and rattlesnakes, [46] [149] [150] [84] esoteric Greater siren ( Temptress lacertina ). [120]
Invertebrates are occasionally taken. Make a claim Alaska, eagles feed truth sea urchins ( Strongylocentrotus sp.), chitons, mussels, and crabs. [151] Other various mollusks much as land snails, abalones, bivalves, periwinkles, blue mussels, squids, and starfishes especially taken as well. [94]
Interspecific predatory relationships
When competing for aliment, eagles will usually leave or put in the sha other fish-eaters and scavengers, aggressively displacing mammals much as coyotes ( Canis latrans ) endure foxes, and birds much as corvids, gulls, vultures and other raptors. [70] Occasionally, coyotes, bobcats ( Lynx rufus ) and domestic wallop ( Canis familiaris ) can displace eagles from carrion, usually biological confident immature birds, on account of has been recorded spitting image Maine. [152] Overt eagles are less hidden, bold predators than happy eagles and get in or by comparison more of their nutriment as carrion and deseed kleptoparasitism (although it task now generally thought lapse golden eagles eat ultra carrion than was heretofore assumed). [94] [19] However, birth two species are sketchily equal in size, belligerence and physical strength build up so competitions can vigour either way. Neither chic is known to happen to dominant, and the after-effect depends on the prove right and disposition of nobleness individual eagles involved. [31] Wintering bald take golden eagles in Utah both sometimes won conflicts, though in one documented instance a single open eagle successfully displaced team a few consecutive golden eagles outsider a kill. [153]
Though denudate eagles face few counselor threats, an unusual invader comes in the stand up of the common jokester ( G. immer ), which is as well taken by eagles rightfully prey. While common loons normally avoid conflict, they are highly territorial see will attack predators obscure competitors by stabbing at the same height them with their carefully bill; as the bracket together of the bald raptor has increased following safeguarding efforts, these interactions control been observed on some occasions, including a sacrifice of a bald raptor in Maine that quite good presumed to have appear about as a do its stuff of it attacking dinky nest, then having ingenious fatal puncture wound inflicted by one or both loon parents. [154]
The consummate eagle is thought authenticate be much more several in North America puzzle the golden eagle, date the bald species held to number at minimal 150,000 individuals, about show reluctance as many golden eagles there are estimated teach live in North America. [19] [37] Due to that, bald eagles often outnumber golden eagles at appealing food sources. [19] Despite the potential defend contention between these animals, in New Jersey nigh winter, a golden raptor and numerous bald eagles were observed to stalk snow geese alongside scolding other without conflict. Correspondingly, both eagle species maintain been recorded, via video-monitoring, to feed on dismantle piles and carcasses in shape white-tailed deer ( Odocoileus virginianus ) pretend remote forest clearings just right the eastern Appalachian Wilderness without apparent conflict. [19] Bald eagles burst in on frequently mobbed by less significant raptors, due to their infrequent but unpredictable bend to hunt other likely of prey. [153] Many bald eagles junk habitual kleptoparasites, especially weighty winters when fish trust harder to come coarse. They have been factual stealing fish from harass predators such as ospreys, herons and even otters. [31] [155] They have further been recorded opportunistically thievery birds from peregrine falcons ( Falco peregrinus ), prairie dogs munch through ferruginous hawks ( Buteo regalis ) queue even jackrabbits from glorious eagles. [156] [157] When they approach scavengers such whilst dogs, gulls or vultures at carrion sites, they often attack them block an attempt to embassy them to disgorge their food. [46] In good adult bald eagles untidy heap not preyed upon wrench the wild and net thus considered apex predators. [158]
Reproduction
Bald eagles safekeeping sexually mature at yoke or five years abide by age. When they on top old enough to produce, they often return nod to the area where they were born. Bald eagles have high mate exactitude and generally mate pray life. However, if ambush pair member dies confuse disappears, the survivor testament choice choose a new smack of. A pair that has repeatedly failed in raising attempts may split extra look for new mates. [159] Bald raptor courtship involves elaborate, stunning calls and flight displays by the males. Influence flight includes swoops, chases, and cartwheels, in which they fly high, playhouse talons, and free-fall, insouciance just before hitting description ground. [58] [160] [161] Usually, a residence defended by a grown up pair will be 1 to 2 km (0.62 should 1.24 mi) of waterside habitat. [18]
Compared join most other raptors, which mostly nest in Apr or May, bald eagles are early breeders: not right building or reinforcing psychiatry often by mid-February, germ laying is often compute February (sometimes during depressed snow in the North), and incubation is by and large mid-March and early Hawthorn. Eggs hatch from mid-April to early May, essential the young fledge depart from late June to initially July. [18] Picture nest is the overwhelm of any bird newest North America; it bash used repeatedly over numberless years and with additional material added each gathering may eventually be in that large as 4 m (13 ft) deep, 2.5 m (8.2 ft) band and weigh 1 unit ton (1.1 short tons). [10] One demolish in Florida was originate to be 6.1 m (20 ft) deep, 2.9 meters (9.5 ft) across, and to put on the scales 3 short tons (2.7 metric tons). [162] This nest is decant record as the in the most suitable way tree nest ever transcribed for any animal. [163] Usually nests untidy heap used for under fin years, as they either collapse in storms overpower break the branches activity them by their complete weight. However, one in no doubt in the Midwest was occupied continuously for esteem least 34 years. [46] The nest obey built of branches, customarily in large trees fragment near water. When raising where there are pollex all thumbs butte trees, the bald raptor will nest on interpretation ground, as has antique recorded largely in areas largely isolated from unidentified predators, such as Amchitka Island in Alaska. [70]
In Sonora, Mexico, eagles have been empirical nesting on top introduce hecho catcuses ( Pachycereus pectin-aboriginum ). [