1 00:00:01,840 --> 00:00:07,640 Speaker 1: Welcome to Brainstuff, a production of iHeartRadio. Hey brain Stuff, 2 00:00:07,680 --> 00:00:12,920 Speaker 1: Lauren Vohlbaum. Here, if you're a fledgling nation selecting a 3 00:00:13,080 --> 00:00:16,040 Speaker 1: national bird, you could do a lot worse than the 4 00:00:16,079 --> 00:00:20,799 Speaker 1: bald eagle. It's got the stately profile and steely eyed gaze, 5 00:00:21,040 --> 00:00:25,320 Speaker 1: the dramatic contrast coloring, and huge wingspan, which is all 6 00:00:25,400 --> 00:00:28,040 Speaker 1: part of why members of Congress chose the bald eagle 7 00:00:28,080 --> 00:00:33,080 Speaker 1: to represent the United States in seventeen eighty nine. For 8 00:00:33,280 --> 00:00:36,000 Speaker 1: the article this episode is based on How Stuffworks, spoke 9 00:00:36,040 --> 00:00:39,080 Speaker 1: with Scott Cordon, wildlife curator at the Center for Wildlife 10 00:00:39,200 --> 00:00:42,239 Speaker 1: Education and the lamar Q Bald Junior Raptor Center at 11 00:00:42,240 --> 00:00:46,559 Speaker 1: Georgia Southern University. Cordon is an expert falconer and manages 12 00:00:46,600 --> 00:00:52,360 Speaker 1: the center's najerie, which includes two bald eagles. First off, 13 00:00:52,400 --> 00:00:56,000 Speaker 1: to be clear, these eagles don't have the bald moniker 14 00:00:56,160 --> 00:01:00,120 Speaker 1: because their heads look hairless, but rather because they're white. 15 00:01:00,480 --> 00:01:04,400 Speaker 1: Their name comes from the Middle English word bald b alde, 16 00:01:05,040 --> 00:01:10,800 Speaker 1: meaning white, but bald eagles don't develop those striking white 17 00:01:10,840 --> 00:01:13,840 Speaker 1: head and tail feathers until they're mature, somewhere between the 18 00:01:13,840 --> 00:01:17,000 Speaker 1: ages of four and five years old. Immature Bald eagles 19 00:01:17,040 --> 00:01:19,640 Speaker 1: are mostly dark brown in color, with mottled brown and 20 00:01:19,640 --> 00:01:23,240 Speaker 1: white wings. They also don't fully develop the bright golden 21 00:01:23,319 --> 00:01:27,360 Speaker 1: yellow coloration on their beaks and feet until they're mature. 22 00:01:28,080 --> 00:01:31,000 Speaker 1: When they reach full size, bald eagles are big, with 23 00:01:31,080 --> 00:01:35,039 Speaker 1: the female eagles growing a bit larger than males. Overall, 24 00:01:35,080 --> 00:01:37,800 Speaker 1: they can weigh around nine to fourteen pounds that's about 25 00:01:37,840 --> 00:01:40,280 Speaker 1: four to six and a half kilos, with a wingspan 26 00:01:40,360 --> 00:01:42,360 Speaker 1: of around five and a half to seven feet or 27 00:01:42,400 --> 00:01:46,200 Speaker 1: about one point six two one point two meters. Only 28 00:01:46,240 --> 00:01:48,920 Speaker 1: a few other North American birds, like the golden eagle 29 00:01:48,960 --> 00:01:53,920 Speaker 1: and the California condor, are as large or larger. Bald 30 00:01:53,960 --> 00:01:57,040 Speaker 1: eagles are in the sea eagle family, meaning they live 31 00:01:57,120 --> 00:02:00,520 Speaker 1: near rivers and coasts and hunt mostly fish and white fowl, 32 00:02:01,200 --> 00:02:04,960 Speaker 1: but they're considered opportunistic carnivores, which means that they usually 33 00:02:05,000 --> 00:02:09,160 Speaker 1: eat whatever is available, including other small game like rabbits, squirrels, 34 00:02:09,240 --> 00:02:12,000 Speaker 1: or rodents, plus deadfish that have washed up on shore, 35 00:02:12,320 --> 00:02:15,600 Speaker 1: or even stolen prey from other birds such as osprey's. 36 00:02:17,240 --> 00:02:20,280 Speaker 1: The scientific name for this type of food snatching behavior 37 00:02:20,639 --> 00:02:25,720 Speaker 1: is klepto parasitism, but it's most common among the immature birds. 38 00:02:26,280 --> 00:02:30,120 Speaker 1: Once mature, bald eagles can be formidable hunters. When a 39 00:02:30,160 --> 00:02:33,080 Speaker 1: bald eagle swoops down to catch its prey, it uses 40 00:02:33,080 --> 00:02:36,200 Speaker 1: its razor sharp talons to snatch the unlucky animal it's 41 00:02:36,240 --> 00:02:39,080 Speaker 1: decided to make a meal out of. They'll roam a 42 00:02:39,160 --> 00:02:42,360 Speaker 1: pretty wide hunting territory about twenty five miles across some 43 00:02:42,560 --> 00:02:46,480 Speaker 1: forty kilometers. But for all that, your average bald eagle 44 00:02:46,560 --> 00:02:48,919 Speaker 1: can easily live off of a couple of adult rats 45 00:02:48,960 --> 00:02:52,960 Speaker 1: per day. Corton said, most birds don't eat every day 46 00:02:53,040 --> 00:02:55,639 Speaker 1: because they'll catch something that's large enough to sustain them 47 00:02:55,680 --> 00:02:58,359 Speaker 1: for a couple of days. Instead, they might feed off 48 00:02:58,360 --> 00:03:01,160 Speaker 1: of something large and fill their a part of their 49 00:03:01,200 --> 00:03:04,360 Speaker 1: digestive system where they temporarily store food that can sustain 50 00:03:04,400 --> 00:03:09,080 Speaker 1: them for two or three days, sometimes even longer. A 51 00:03:09,120 --> 00:03:12,600 Speaker 1: Bald eagles are the only sea eagles endemic to North America, 52 00:03:13,160 --> 00:03:16,520 Speaker 1: and they really have the territory covered. The bald eagles 53 00:03:16,600 --> 00:03:20,160 Speaker 1: range stretches from southern Alaska to northern Mexico and from 54 00:03:20,160 --> 00:03:23,640 Speaker 1: coast to coast. Due to their distinctive plumage, they are 55 00:03:23,639 --> 00:03:27,480 Speaker 1: almost impossible to mistake with other birds, even other large eagles. 56 00:03:28,040 --> 00:03:30,360 Speaker 1: When you see that white head soaring above the trees, 57 00:03:30,560 --> 00:03:34,360 Speaker 1: it's a bald eagle for sure. These birds can be 58 00:03:34,520 --> 00:03:37,880 Speaker 1: very social under the right circumstances. When food is plentiful 59 00:03:38,000 --> 00:03:41,280 Speaker 1: and it's not nesting season, a few to a few 60 00:03:41,440 --> 00:03:44,320 Speaker 1: hundred may roost together and have been observed engaging in 61 00:03:44,320 --> 00:03:48,040 Speaker 1: play behavior even as adults. They also mat for life, 62 00:03:48,280 --> 00:03:50,560 Speaker 1: though if one of a pair dies, the surviving birds 63 00:03:50,600 --> 00:03:54,160 Speaker 1: sometimes finds a new mate and they take nesting seriously. 64 00:03:55,040 --> 00:03:58,520 Speaker 1: Mates built nests called aries together, which takes around one 65 00:03:58,560 --> 00:04:01,840 Speaker 1: to three months. They also trade parental duties, with both 66 00:04:01,840 --> 00:04:04,080 Speaker 1: birds incubating the eggs for the five weeks or so 67 00:04:04,120 --> 00:04:07,920 Speaker 1: that it takes for them to hatch, because it takes 68 00:04:07,960 --> 00:04:10,440 Speaker 1: the hatchlings ten to twelve weeks to grow to the 69 00:04:10,440 --> 00:04:13,040 Speaker 1: point that they fledge, that is, take their first flight. 70 00:04:13,480 --> 00:04:16,080 Speaker 1: Eagles only lay one clutch or a group of eggs 71 00:04:16,160 --> 00:04:20,680 Speaker 1: per year. Cordon said. If their eggs or their young 72 00:04:20,720 --> 00:04:23,560 Speaker 1: are destroyed early enough in the season, they will lay 73 00:04:23,600 --> 00:04:27,200 Speaker 1: another clutch to try to reproduce again. In fact, that's 74 00:04:27,240 --> 00:04:29,960 Speaker 1: part of how they got the bald eagle population back up. 75 00:04:30,360 --> 00:04:32,560 Speaker 1: They would remove eagle eggs from the nest early in 76 00:04:32,600 --> 00:04:34,960 Speaker 1: the season and the adult eagle would lay another set 77 00:04:35,000 --> 00:04:39,360 Speaker 1: of eggs. It's called a double clutch. Due to these efforts, 78 00:04:39,360 --> 00:04:42,239 Speaker 1: the bald eagle was removed from the federal endangered species 79 00:04:42,279 --> 00:04:44,360 Speaker 1: list in two thousand and seven and is off every 80 00:04:44,360 --> 00:04:47,919 Speaker 1: state endangered species list too, though it's still protected by 81 00:04:48,000 --> 00:04:52,960 Speaker 1: several laws to prevent the population from dipping again. But 82 00:04:53,160 --> 00:04:56,480 Speaker 1: back to those nests. A bald eagles have the largest 83 00:04:56,480 --> 00:04:59,760 Speaker 1: nest of any bird species in North America. Their average 84 00:04:59,760 --> 00:05:02,360 Speaker 1: nest size is up to five feet across and four 85 00:05:02,400 --> 00:05:04,960 Speaker 1: feet deep that's about one point five by one point 86 00:05:05,040 --> 00:05:09,000 Speaker 1: two meters. The biggest arion record was built by pair 87 00:05:09,120 --> 00:05:12,880 Speaker 1: bald eagles in Saint Petersburg, Florida. It measured twenty feet 88 00:05:12,880 --> 00:05:15,599 Speaker 1: by nine feet that's about six by three meters, and 89 00:05:15,680 --> 00:05:20,800 Speaker 1: weighed two tons. A Cordon explained eagles only live in 90 00:05:20,839 --> 00:05:23,720 Speaker 1: their nest during the mating season, incubation, and while they're 91 00:05:23,800 --> 00:05:26,839 Speaker 1: raising the fledglings. Once they learn to fly and everyone 92 00:05:26,920 --> 00:05:30,719 Speaker 1: is out, they don't live in the nest. The birds 93 00:05:30,760 --> 00:05:33,520 Speaker 1: will return to the same nest year after year if possible, 94 00:05:33,880 --> 00:05:36,560 Speaker 1: but will leave if the tree's built in can't sustain it. 95 00:05:38,320 --> 00:05:41,719 Speaker 1: They're also pretty smart. A Courton said, they tend to 96 00:05:41,760 --> 00:05:45,120 Speaker 1: never forget anything, and they hold grudges. If you're training 97 00:05:45,160 --> 00:05:47,240 Speaker 1: an eagle and you make a mistake, that can either 98 00:05:47,320 --> 00:05:52,320 Speaker 1: ruin the training you've done or set you back several months. 99 00:05:52,480 --> 00:05:55,120 Speaker 1: But it's important to note that the bald eagle wasn't 100 00:05:55,160 --> 00:05:57,560 Speaker 1: the only bird in the running for a national symbol. 101 00:05:58,320 --> 00:06:01,320 Speaker 1: A founding father, Benjamin Franklin and favored the turkey as 102 00:06:01,320 --> 00:06:04,960 Speaker 1: the national bird, calling it more respectable and with all 103 00:06:05,080 --> 00:06:09,839 Speaker 1: a true original native of America. Part of Franklin's beef 104 00:06:09,920 --> 00:06:13,160 Speaker 1: was that the bald eagle is a scavenger. Corton said, 105 00:06:13,760 --> 00:06:15,840 Speaker 1: of all the birds of prey other than the vultures, 106 00:06:16,000 --> 00:06:18,680 Speaker 1: bald eagles will most readily go to a dead animal 107 00:06:18,720 --> 00:06:20,800 Speaker 1: on the side of the road, where other birds of 108 00:06:20,800 --> 00:06:25,680 Speaker 1: prey will only carry in if they're starving. Nevertheless, the 109 00:06:25,680 --> 00:06:28,640 Speaker 1: bald eagle was chosen as a symbol of strength, courage, 110 00:06:28,640 --> 00:06:32,720 Speaker 1: and freedom, and despite Franklin's comments, the bald eagle is 111 00:06:32,720 --> 00:06:40,840 Speaker 1: indigenous only to North America. Today's episode is based on 112 00:06:40,880 --> 00:06:43,400 Speaker 1: the article Bald Eagle, size, diet and History is a 113 00:06:43,480 --> 00:06:46,680 Speaker 1: National Icon on HowStuffWorks dot com, written by Patty Rasmusen 114 00:06:47,200 --> 00:06:49,560 Speaker 1: Brain Stuff is production of by Heart Radio in partnership 115 00:06:49,560 --> 00:06:52,040 Speaker 1: with HowStuffWorks dot Com and is produced by Tyler Klang. 116 00:06:52,600 --> 00:06:55,640 Speaker 1: Four more podcasts my heart Radio, visit the iHeartRadio app, 117 00:06:55,760 --> 00:07:04,440 Speaker 1: Apple Podcasts, or wherever you listen to your favorite shows.