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Bald Eagles. National bird of the United States http ://www.baldeagleinfo.com/eagle/eagle11.html. History. Fossil remains of ancient sea eagles date back some 25 million years, long before humans There are 59 different species of Eagles
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Bald Eagles National bird of the United States http://www.baldeagleinfo.com/eagle/eagle11.html
History • Fossil remains of ancient sea eagles date back some 25 million years, long before humans • There are 59 different species of Eagles • Bald Eagles were declared the US National emblem in 1782. They symbolize freedom, spirit and pursuit of excellence. • Life span 15-30 years
History continued….. • At one time bald eagles were very common in most of the US • 100,000 - 300,000 in the early 1700’s • By 1963 only about 800 Bald Eagles were left • Today there are about 50,000 Bald Eagles • 80% are found in Alaska
Our National Emblem • The eagle represents freedom • On the backs of our gold coins, the silver dollar, the half dollar and the quarter, we see an eagle with outspread wings. • It is said the eagle was used as a national emblem because, at one of the first battles of the Revolution and the noise of the struggle awoke the sleeping eagles on the heights and they flew from their nests and circled about over the heads of the fighting men, and calling out with shrieks. "They are shrieking for Freedom," said the patriots
How Bald Eagles became endangered! • DDT AND OTHER PESTICIDES WERE SPRAYED ON CROPS. • THE PESTICIDES WERE WASHED INTO LAKES AND STREAMS. • THE PESTICIDES WERE ABSORBED BY AQUATIC PLANTS AND SMALL ANIMALS. • FISH ATE THE PLANTS AND SMALL ANIMALS. • THE EAGLES ATE THE FISH. • THIS PRODUCED THIN EGG SHELLS THAT WOULD CRACK AND NOT HATCH. • THE BALD EAGLE ATE ANIMALS THAT HAD BEEN SHOT BY HUNTERS USING LEAD SHOT, THE LEAD WHEN INJESTED CAUSED DEATH FOR THE BALD EAGLE.
DDT(dchlorodphenyltrichloroethane) • Pesticide used in crops to kill of mosquitoes. Thought mosquitoes carried malaria • Used after WWll • Figured since it didn’t hurt humans didn’t think it would hurt animals • They were WRONG http://www.greenhealthlive.com/index.php?main_page=document_general_info&products_id=185
Effects of DDT • The DDT pesticide ran into streams and lakes • Affected many animals • Bald Eagles would consume insects, small birds, and fish infected with DDT • When mother Bald Eagles would eat infected food it would build up in her body and cause egg shells to form thin • With shell too thin they would become over heated and would crack before chicks were developed
Continue of DDT. . . . This caused a huge decrease in the Bald Eagle population. http://www.scienceclarified.com/Co-Di/DDT-dichlorodiphenyltrichloroethane.html
Rachel Carson Told people about dangers of DDT. Nature Author and Biologist Has a book called “Silent Spring” http://naturalpatriot.org/2007/05/27/rachel-carson-natural-patriot/
Silent Spring Book • the book argued that uncontrolled pesticide use was harming and even killing not only animals and birds, but also humans. • This book gives detail on how DDT enters the food chain and how it builds up in animals. • The book led the U.S ban DTT in 1972, although some other countries still continue to use DDT. • Silent Spring was recently rated #25 for the greatest science book of all time.
Characteristics • They have white heads with white tail feathers • Their beaks, eyes and feet are yellow • Dark brown bodies • They can live up to 15-to 30 years http://www.nhptv.org/natureworks/baldeagle.htm
Characteristics cont…. • They have around 7000 feathers on their body • Weigh around 10 to 15pounds • Wing span is around 7feet in females and males are around 6 feet • Length is around 3 feet, males are smaller http://bdml.stanford.edu/twiki/bin/view/Rise/AlexisLD
Bald Eagles are raptors Raptors are “birds of prey”, meaning they are carnivores. They eat meat All raptors share 3 characteristics: 8 sharp talons, keen eyesight, and hooked beaks Eagles, Hawks, Owls and Vultures are all raptors http://gremlynzzz.blogspot.com/
Feeding • Mostly survive off of fish, only 1 out of 18 attempts are successful. • Will also eat rodents, rats, muskrats and ducks. • Can consume 1lb of fish in 4 minutes • Road kill deer are their favorite food in the Midwest • They rely on carrion • Bald Eagles steal food from other raptors or other bald eagles • Day time hunters • Do not have to eat everydayhttp://www.wildnatureimages.com/bald_eagle%20eating%20fish.htm
Beaks of Bald Eagles • The beak grows continually through it’s life • The hook of the bald eagle is used for tearing apart prey • The upper and the lower portion overlap and act as a scissors that way it can tear through skin http://www.alaska-in-pictures.com/bald-eagle-beak-854-pictures.htm
Feet • Feet called Talons • Used to penetrate the flesh of prey • Talons are very powerful • 4 large toes and grooved underneath, Pad are like little needles • Like the beaks the talons grow continuallyhttp://www.elcivics.com/el_civics_bald_eagle_p2
Eyes • Great eye sight and colored vision • Bald Eagles can spot a fish hundreds of feet above water. • When perched they can spot prey a mile away • Eagles can see both forward and to it’s side at the same timehttp://indianapublicmedia.org/amomentofscience/eagle-eyes/
Behavior • bald eagles are not picky about how it gets its food. It will eat carrion (road kill), steal fish from other birds or hunt for its own. Their most important food is fish, which they catch by swooping down and grabbing fish that are near the surface of the lake or streams. • Bald eagles make a high-pitched squeaking sound. Other interesting behaviors include “talon clasping” or “cartwheel display”, where two eagles clasp each other’s talons in mid air and spin down, letting go only when they’ve almost reached the ground. This can be a courtship ritual as well as a territorial battle. • During breeding season, the male and female work together to build their nest of sticks, usually located at the top of a tree. The nests can weigh up to a ton and measure up to 8 feet across. Once paired, bald eagles remain with each other until one mate dies, then the surviving bird will find another mate. They also keep the same nest just doing upkeep to it.
The Call of Bald Eagles • Bald Eagles use their call for communication • They may warn other eagles if predators are in the area • Using their call to communicate with others along with their mate • The bald eagle gives a series of chirps at the nest and a loud scream during flight.
Reproduction • sexual maturity:An eagle reaches sexual maturity at around four or five years of age. At that time, the eagle's spends most it’s time on finding a mate and raising offspring. • Mating season: Anywhere from late September to early April, depending on where they live. • Gestation: The female lays her first egg 5-10 days after mating. The eggs are incubated for about 35 days. • Clutch size: 1-3 eggs. Both parents take turns sitting on the eggs, but the female spends most of her time in the nest. When three are laid, however, it is very rare that all the young will survive. While one parent sits on the eggs, the other will hunt and collect materials for nest to keep it up. When the young hatch, their eyes are open and they are covered in light grey down.
Eaglets • The eggs hatch in the order they were laid. Eaglets break through the shell by using their egg tooth, a pointed bump on the top of the beak. • It can take from twelve to forty-eight hours to hatch after making the first break in the shell. The male provides the majority of the food needed for his family. • Eventually the female will help out with the hunting, but in the early days, all of her attention is given to the young eaglets in the nest. http://www.wildlifeextra.com/go/news/ireland_golden-eagles.html#cr
Eaglet Growth • they add one pound to their body weight every four or five days. • At about two weeks, it is possible for them to hold their head up for feeding. • By three weeks they are 1 foot high and their feet and beaks are very nearly adult size. • Between four and five weeks, the birds are able to stand, at which time they can began tearing up their own food. • At six weeks, the eaglets are very nearly as large as their parents. Black juvenile feathers will begin to grow in. • At eight weeks, the appetites of the young birds are at their greatest. While parents hunt almost continuous to feed them, back at the nest the eaglets are beginning to stretch their wings in response to gusts of wind. • At 10 to 13 weeks all the down feathers are replaced with juvenile feather before an eaglet can take its first flight
Juvenile Eagles • Only 40% survive their first flight • After leaving the nest they practice their ability to fly and hunt. It is survival time for the Eagles, the parents can’t tell them how to hunt, they have to watch the parents and practice. At first they watch their pray more than they try to attack it • Until the first winter after they have left nest, young eagles near the nest are often still fed by their parents, but have little other contact with them. Although a young eagle has the instincts to hunt, it lacks the skills. Eventually, they learn to soar and spot prey. If food is scarce during the winter, it could die. • When juvenile eagles mature, their head and tail feathers gradually turn white. At the same time their eyes and beak gradually turn yellow. • This normally happens between the age of 5 to 7.
Reasons for Death Most common reason why Bald Eagles die: - starvation - electrocution - Cars - gun shots - Drowning - Habitat loss - Pesticides/leads http://www.google.com/url?q=http://www.wildnatureimages.com/Dead_Bald_Eagle.htm&ei=tOWWTIvaEoLfnAe2pomGBw&sa=X&oi=unauthorizedredirect&ct=targetlink&ust=1284959420308997&usg=AFQjCNFlpG-6RLzjzj1Kp9W9kucV_kdmtQ
Efforts to save the Eagles in the past • Endangered Species Act, they were listed in 1973 • Endangered Species Preservation Act, 1966 • Environmental Protection Agency, banning of DDT in 1972 • Bald Eagle Protection Act, stopping from killing or selling Bald Eagles in 1940
Current efforts to help Bald Eagles • Bald Eagles are currently listed threatened on the Endangered Species Act • In 1999 it was talked about delisting the Bald Eagles but remain on the list. • Migratory Bird Treaty Act, which protects all migratory birds which include the Bald Eagle in the U.S • This act prohibits killing, taking, possessing, transporting, and importing migratory birds, their eggs, parts and nests.
How you can help! • Do not litter! Everyone can easily help clean up our lands. • Drive careful and look out for animals and birds • Keep chemicals safe • Fish with lead free lures http://www.nhptv.org/natureworks/baldeagle.htm
References 1930s, t., population, p. b., hatch, w. o., tissues, i. d., eagles, g. o., & individuals, e. 1. (n.d.). History of the Bald Eagle. American Bald Eagle Information. Retrieved September 10, 2010, from http://www.baldeagleinfo.com/eagle/eagle11.html American Bald Eagle Photo Lesson with Facts and Pictures. (n.d.). Civics Lessons and EL Civics Activities for ESL Students. Retrieved September 20, 2010, from http://www.elcivics.com/el_civics_bald_eagle_p2 Bald Eagle Photo. (n.d.). Alaska Photographer Ron Niebrugge. Retrieved August 31, 2010, from http://www.wildnatureimages.com/bald_eagle%20eating%20fish.htmBald Eagle's Eyesight and Hearing. (n.d.). American Bald Eagle Information. Retrieved September 10, 2010, from http://www.baldeagleinfo.com/eagle/eagle2.html
References cont… Bald Eagle's Eyesight and Hearing. (n.d.). American Bald Eagle Information. Retrieved September 10, 2010, from http://www.baldeagleinfo.com/eagle/eagle2.html DDT (dichlorodiphenyltrichloroethane) - humans, body, used, water, plants, chemical, animals, parts, effects, cause, substance, principle, DDT as an insecticide. (n.d.). Science Clarified. Retrieved August 28, 2010, from http://www.scienceclarified.com/Co-Di/DDT-dichlorodiphenyltrichloroethane.html Desbier, A. (n.d.). Stuff I am working on. Biomimetics and Dexterous. Retrieved August 10, 1928, from bdml.stanford.edu/twiki/bin/view/Rise/AlexisLD
Continue….. Eagle Eyes | A Moment of Science - Indiana Public Media. (n.d.). Indiana Public Media | News and Information, Music, Arts and Community Events from WFIU and WTIU. Retrieved September 20, 2010, from http://indianapublicmedia.org/amomentofscience/eagle-eyes/ Halvers, M. (n.d.). Green Health. Green Health Live, The All Natural Interactive Internet TV Show. Retrieved September 5, 2010, from http://www.greenhealthlive.com/index.php?main_page=document_general_info&products_id=185 Redirect Notice. (n.d.). Google. Retrieved September 20, 2010, from http://www.google.com/url?q=http://www.wildnatureimages.com/
Continue…… Dead_Bald_Eagle.htm&ei=tOWWTIvaEoLfnAe2pomGBw&sa=X&oi=unauthorizedredirect&ct=targetlink&ust=1284959420308997&usg=AFQjCNFlpG-6RLzjzj1Kp9W9kucV_kdmtQ Status and future of bald eagles.. (n.d.). American Bald Eagle Information. Retrieved September 20, 2010, from http://www.baldeagleinfo.com/eagle/future.html The Bald Eagle - USA's National Emblem. (n.d.). American Bald Eagle Information. Retrieved September 10, 2010, from http://www.baldeagleinfo.com/eagle/eagle9.htmlhigh, t. w., feet, t., & size., b. a. (n.d.). American Bald Eagle - Nesting & Young. American Bald Eagle Information. Retrieved September 20, 2010, from http://www.baldeagleinfo.com/eagle/eagle4.html