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Bald Eagle


Bald Eagle
Photo Information
Copyright: Peter van Zoest (PeterZ) Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 5136 W: 166 N: 13121] (49139)
Genre: Animals
Medium: Color
Date Taken: 2012-07-24
Categories: Birds
Camera: Nikon D300, AF Nikkor 70-300mm f4-5.6 G, Digital RAW
Exposure: f/4.5, 1/400 seconds
Details: Tripod: Yes
Photo Version: Original Version
Date Submitted: 2013-04-20 7:51
Viewed: 2134
Points: 44
[Note Guidelines] Photographer's Note
Still a juvenile Bald Eagle. Born in bird park Avifauna.

The Bald Eagle (Haliaeetus leucocephalus) is a bird of prey found in North America. It is the national bird and symbol of the United States of America. This sea eagle has two known sub-species and forms a species pair with the White-tailed Eagle. Its range includes most of Canada and Alaska, all of the contiguous United States, and northern Mexico. It is found near large bodies of open water with an abundant food supply and old-growth trees for nesting.

Taxonomy
This sea eagle gets both its common and scientific names from the distinctive appearance of the adult's head. Bald in the English name is derived from the word piebald, and refers to the white head and tail feathers and their contrast with the darker body. The scientific name is derived from Haliaeetus, New Latin for "sea eagle" (from the Ancient Greek haliaetos), and leucocephalus, Latinized Ancient Greek for "white head," from λευκος leukos ("white") and κεφαλη kephale ("head").

The Bald Eagle was one of the many species originally described by Linnaeus in his 18th century work Systema Naturae, under the name Falco leucocephalus.

There are two recognized subspecies of Bald Eagle:
• H. l. leucocephalus (Linnaeus, 1766) is the nominate subspecies. It is separated from H. l. alascanus at approximately latitude 38° N, or roughly the latitude of San Francisco. It is found in the southern United States and Baja California.
• H. l. washingtoniensis (Audubon, 1827), synonym H. l. alascanus Townsend, 1897, the northern subspecies, is larger than southern nominate leucocephalus. It is found in the northern United States, Canada and Alaska. This subspecies reaches further south than latitude 38° N on the Atlantic Coast, where they occur in the Cape Hatteras area.

Population decline and recovery
Once a common sight in much of the continent, the Bald Eagle was severely affected in the mid-20th century by a variety of factors, among them the thinning of egg shells attributed to use of the pesticide DDT. Bald Eagles, like many birds of prey, were especially affected by DDT due to biomagnification. DDT itself was not lethal to the adult bird, but it interfered with the bird's calcium metabolism, making the bird either sterile or unable to lay healthy eggs. Female eagles laid eggs that were too brittle to withstand the weight of a brooding adult, making it nearly impossible for the eggs to hatch. It is estimated that in the early 1700s, the bald eagle population was 300,000–500,000, but by the 1950s there were only 412 nesting pairs in the 48 contiguous states of the US. Other factors in Bald Eagle population reductions were a widespread loss of suitable habitat, as well as illegal shooting, which was described as "the leading cause of direct mortality in both adult and immature bald eagles," according to a 1978 report in the Endangered Species Technical Bulletin. In 1984, the National Wildlife Federation listed hunting, power-line electrocution, and collisions in flight as the leading causes of eagle deaths. Bald Eagle populations have also been negatively affected by oil, lead, and mercury pollution, and by human and predator intrusion.

The species was first protected in the U.S. and Canada by the 1918 Migratory Bird Treaty, later extended to all of North America. The 1940 Bald Eagle Protection Act in the U.S., which protected the Bald Eagle and the Golden Eagle, prohibited commercial trapping and killing of the birds. The Bald Eagle was declared an endangered species in the U.S. in 1967, and amendments to the 1940 act between 1962 and 1972 further restricted commercial uses and increased penalties for violators. Also in 1972, DDT was banned in the United States. DDT was completely banned in Canada in 1989, though its use had been highly restricted since the late 1970s.

It was officially removed from the U.S. federal government's list of endangered species on July 12, 1995, by the U.S. Fish & Wildlife Service, when it was reclassified from "Endangered" to "Threatened." On July 6, 1999, a proposal was initiated "To Remove the Bald Eagle in the Lower 48 States From the List of Endangered and Threatened Wildlife." It was de-listed on June 28, 2007. It has also been assigned a risk level of Least Concern category on the IUCN Red List.

Reproduction
Bald Eagles are sexually mature at four or five years of age. When they are old enough to breed, they often return to the area where they were born. It is thought that Bald Eagles mate for life. However, if one member of a pair dies or disappears, the other will choose a new mate. A pair which has repeatedly failed in breeding attempts may split and look for new mates. Bald Eagle courtship involves elaborate, spectacular calls and flight displays. The flight includes swoops, chases, and cartwheels, in which they fly high, lock talons, and free fall, separating just before hitting the ground. Usually, a territory defended by a mature pair will be 1 to 2 km of waterside habitat.

Compared to most other raptors which mostly nest in April or May, bald eagles are early breeders: nest building or reinforcing is often by mid-February, egg laying is often late February (sometimes during deep snow in the North), and incubation is usually mid-March and early May. Eggs hatch from mid April to early May, and the young fledge late June to early July. The nest is built out of branches, usually in large trees found near water. When breeding where there are no trees, the Bald Eagle will nest on the ground, as has been recorded largely in areas largely isolated from terrestrial predators.

Longevity
The average lifespan of Bald Eagles in the wild is around 20 years, with the oldest confirmed one having been 28 years of age. In captivity, they often live somewhat longer. In one instance, a captive individual in New York lived for nearly 50 years. As with size, the average lifespan of an eagle population appears to be influenced by its location and access to prey. As they are no longer heavily persecuted, adult mortality is quite low.

Different sources internet.

Silvio2006, CeltickRanger, jusninasirun, maaciejka, anel, Jakkals, Pitoncle, Chiza has marked this note useful
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Critiques [Translate]

Ciao Peter, great portrait of superb eagle in fantastic pose, fine details, splendid sharpness and wonderful natural colors, very well done, my friend, ciao Silvio

Hallo BUURMAN-Peter
Weer toevallig naast elkaar
Je hebt hier een super goode opname ,super details en leuke pose zo tussen de rotsen
de kleuren zijn prachtig en natuurlijk

Hoop is op morgen ,er is dan weinig wind en met een beetje zon erbij ????prachtig
gr lou

Hello Peter,
Another impressive capture,outstanding details and clarity,beautiful composition and nice saturation of natural colours.
Thanks and best regards,
Joy

  • Great 
  • KOMSIS Gold Star Critiquer/Gold Note Writer [C: 821 W: 0 N: 2414] (10640)
  • [2013-04-20 10:52]

Hallo Peter,
Flashy Eagle ..
Superb POV, good details and nice and smooth BG.
Have a nive weekend,
Seyfi

  • Great 
  • lousat Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 6475 W: 89 N: 15608] (65295)
  • [2013-04-20 11:23]

Hi Peter,really beautiful!What a georgeous pose and imposing perspective,looks like a star in the bird world,magnificent capture and excellent quality as usual.Have a nice evening and thanks,Luciano

Hello Peter

Excellent portrait of the Bald Eagle with its
bird of prey proud pose, fine POV to show its plumage,
excellent focus, sharpness, and details, TFS

Asbed

Hello Peter,
Excellent photograph of Bald Eagle, excellent sharpness and details, excellent composition, excellent background and lighting.
Tfs,
Daystar-7

  • Great 
  • tuslaw Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 2752 W: 280 N: 4931] (19883)
  • [2013-04-20 14:47]

Hello Peter,
It is always a thrill to view the Bald Eagle which is our National Symbol. What a beautiful close-up shot of this particular bird. Great work!!
I know it takes about five years for them to obtain their white head and tail, so do you know about how old this bird is?
Ron

Hello Peter.
This is a majestic pose of a proud looking bird. Excellent exposure control with vivid details of the feather. Nice close framing and thanks for sharing.
Have a wonderful weekend.
Regards,
Jusni

Hello Peter,
An amazing portrait of a juvenile Bald Eagle.
Expression of the bird is great.
sharpness, colour and light is class one.
best wishes,
samiran

你好
照的很清晰
老鷹可愛 羽毛顏色鮮明
構圖也美麗
謝謝分享
STONE

Hi Peter,
excellent photo of the eagle. Interesting and spectacular bird. Perfect pose you have captured. Amazing colours. A lot of details.
Have a nice Sunday,
Maciek

  • Great 
  • anel Gold Star Critiquer/Gold Note Writer [C: 3053 W: 3 N: 8715] (40574)
  • [2013-04-21 5:27]

hello peter,
Even if taken in a zoo, this picture is so lovely for its composition and the right point of view chosen giving the nice background to the shot. A magnificent bird, this Bald Eagle!
Thanks!
Anne

Hallo Peter,
An Impressive bird captured in equally impressive technical aspects. Excellent POV showing the yellow eye and plumage with sharp clear detail. What I like is the Eagle etched against the light green BG which makes the eagle stand out more in all it's glory.
Best regards my friend,
Carl

Hello Mr.Peter,
Beautiful photograph of this 'Bald Eagle'.Nice POV and sharpness.I like its details too.Excellent work.
Thanks for sharing,
Kind regards,
Srikumar

Bonjour Peter,
Très belle attitude du sujet et excellente profondeur de champ.
A bientôt sur TN pour de nouvelles aventures.
Gérard

Hello Peter,
the is very nice picture of the Bald Eagle.
The eagle is well exposed, accurate WB, sharp with good details.
Its also well composed and the bird is in a nice pose.
Well, mf
Regards
Gert

I think you must have largest album of birds in the entire TN, it's great.

  • Great 
  • iti Gold Star Critiquer/Gold Note Writer [C: 577 W: 0 N: 650] (7939)
  • [2013-04-22 10:35]

Hi Peter,
Beautiful eagle with majestic pose. Perfect sharpness details in nice natural colours.
Regards Jiri.

  • Great 
  • IronM Gold Star Critiquer/Gold Note Writer [C: 144 W: 3 N: 345] (2608)
  • [2013-04-22 11:04]

Hi Peter,
wonderful photo of an eagle, very powerful !
Outstanding details , beautiful lighting , lovely composed, perfect BG !
Best regards !

Hello Peter,
Once again a wonderful photo taken from a very good angle and POV. Exceptional quality....Excellent details. Outstanding colors and perfect focus.
Very difficult to catch in the wild such a superb image with this shy bird....You are lucky that you can visit this interesting bird park Avifauna. In my country we do not have such a bird sanctuary. You managed perfect this composition.
Thanks for sharing!
Marius.

Ciao Peter. Great time. Perfect details and sharp. Magnificent portrait indeed.

Roberto

  • Great 
  • Chiza Gold Star Critiquer/Gold Note Writer [C: 133 W: 0 N: 474] (5351)
  • [2013-04-28 11:35]

Hola Peter, que hermosa foto de esta imponente ave, se nota la potencia y fuerza en esta espectacular retrato...saludos.

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