nctc_eaglecam@fws.gov
Eagle Nest Updates
Spring Update #2 - April 15, 2009
It has been a wet and chilly spring thus far. The second egg finally vanished a week or two ago, leaving us with the one eaglet for the season.
The adults have spent a good deal of time keeping the eaglet warm and dry. The first sign of new feathers are appearing on the eaglet, and it continues to grow steadily. Our proximity to the Potomac river ensures that their is a bountiful supply of fish, but we have noticed several squirrels and other small mammals. Likely most of these are road kill, although a freshly killed squirrel means that the eagles could be catching them live.
Spring Update #1 - March 23, 2009
As of today, we have one eaglet, and one remaining egg. It seems unlikely that this last egg will hatch out, the longer it takes the more improbable a hatch becomes. There are many reasons that eggs can not be viable, including cold temperatures and moisture. We'll probably never know what happened this year, but we can celebrate our one new eaglet.
Winter Update #2 - March 16, 2009
Our first egg hatched out on Saturday, and the young eaglet looks healthy. The other two eggs are still in the nest, but have been hard to see. We hope they hatch out as well in the next several days.
Typically, bald eagle eggs will hatch in about 35 days, but there are instances where the time is as long as 45 days.
Remember that not all eggs are viable, although these adults have been very diligent this year in keeping the eggs warm and dry.
Winter Update #1 - February 5, 2009
There's been a lot of action at the NCTC nest this week. The first egg of the season was laid on Saturday, January 31, and the second egg was laid Monday, February 2. We are hoping for a third egg in the next 12-18 hours or so. Only time will tell, but this pair has a good track record for three eggs.
Here's Bent's description of the eagle eggs:
" Eggs.--Two eggs almost invariably make up a full set for the bald eagle, sometimes only one, and rarely three; in two or three cases four eggs have been found in a nest, but these may have been the product of two females. The eggs vary in shape from rounded-ovate to ovate, the former predominating. The shell is rough or coarsely granulated. The color is dull white or pale bluish white and unmarked, though often nest stained. Very rarely an egg shows a few slight traces of pale brown or buff markings.
The measurements of 50 eggs from Florida average 70.5 by 54.2 millimeters; the eggs showing the four extremes measure 78.8 by 56.2, 71.1 by 57.6, and 58.1 by 47 millimeters. The eggs are ridiculously small for large a bird. (Compare the relative sizes of the eggs of the ruddy duck, the sandpipers, or the hummingbirds.) Consequently the little eaglet requires a long time to develop."--[Published in 1937: Smithsonian Institution United States National Museum Bulletin 167 (Part 1): 321-333]
Incubation is about 34-35 days, where both eagles will take turns keeping the eggs warm. The nest and the parents will protect the eggs from the dangers of cold and dampness, but we are always wary of bad weather, as it can have a devastating effect on the eggs, as happened in 2007.
The eagle cam has had approximately 32,000 hits since we cranked it back up 22 days ago.
Spring Update #4 - June 23, 2008
The nest is now empty, with all three eaglets now successful fledglings. They are still in the area of the nest, and continue to eat fish and other things brought to the nest by the adult pair. As the summer progresses, we'll see less and less of them, and they will finally move on, not to be seen around this nest again.
Spring Update #3 - June 2, 2008
It is the first of June and our three eagle offspring are nearing the time for their first flight. Here's what Bent has to say about this time in the eaglet's development:
"With the increase in size and strength comes an increase in activity, with more time devoted to play and exercise in preparation for flight. Activities begin by walking or jumping about the nest, which soon becomes trodden quite flat, picking up and playing with sticks, learning to grasp objects in the talons, and stretching and flapping their growing wings. With tail raised and head lowered the eaglet backs up to the edge of the nest and shoots its liquid excreta clear of the nest to form a "whitewashed" circle on the ground below. Later on the flight exercises begin in earnest, of which Dr. Herrick (1924c) writes:
After a while a simple routine is established--raising the wings until they seem to touch over the back, taking a few strokes and jumping; the flapping gradually comes to take their feet above the floor of the eyrie and at eight weeks of age they may be able to rise two feet or more in the air; this ability attained, they are liable to go higher and higher and in a fairly stiff breeze, which helps to sustain if not stimulate them, they begin to soar and hover. In 1922 we said "good-bye" to the Eaglets more than once before knowing the long practise they required to produce that perfect coordination of muscles and nerves which was necessary for confidence in the air. During the last week of regular eyrie life in that year they would sometimes rise to a height of fifteen feet, and soar for a full minute, going even beyond the confines of the nest and always with talons down to facilitate landing upon their return.
At last the day comes for the eaglets to leave the nest. Sometimes they do so voluntarily; but in some cases it seems necessary to use persuasion. In Dr. Herrick's (1924c) "first season with the Eagles the young seemed disinclined to leave their eyrie and were finally starved out and lured away." After two days of scanty feeding and two days of fasting, "as the old Eagle with the fish was circling just above the nest the Eaglet was jumping with legs rigid and flapping frantically; suddenly it leaped into the air, and for a second seemed to hang, as if poised over the eyrie; at that moment the circling Eagle began to scream, and swooping down at the hovering and now screaming youngster passed him within six feet; a minute later the Eaglet, still holding to the air, drifted fifteen feet or more beyond the margin of the nest; with vigorous wing-beats it began to move eastward, following the mother bird with the fish and made a full mile in its first independent flight; it finally landed in the branches of a tree on the edge of a strip of woods and doubtless was there allowed to feed on the tantalizing fish."
For some time after they leave the nest, probably all through their first summer, the young eagles associate with their parents in the home territory and frequently return to the nest or their favorite perches. But they are eventually driven out to earn their own living and seek new territory. They are never allowed to establish a breeding station near their parental home."
Spring Update #2 - May 8, 2008
Our three eaglets are rapidly approaching the time where they will fledge from the nest. We're estimating that will take place in early June.
Their feathers continue to grow in, and when they open their wings it is amazing to see how big they are after a couple of months of growth. The adults continue to bring lots of fish, and are still careful to ensure all three eagles get their fill of food.
Both adults have been leaving the area of the nest more often now, as the threat of predators is not really an issue considering the size of the young eagles, although one is often seen perched above the nest.
Keep watching.
Here’s some info from Bent’s Life Histories of Familiar American Birds:
Although often two, sometimes three, eaglets are hatched, the larger number is seldom raised to maturity, and often only one eaglet lives to grow up. The young hatch at intervals of a few days and the first one hatched, often the female, is larger and stronger than the other. The larger eaglet often abuses the smaller one and gets more than its share of the food, until the poor little one succumbs and dies of weakness and exposure. Dr. Herrick (1932) writes:
Two eaglets were hatched in that season on about April 24 and 28, and the younger bird was handicapped not only on account of its lesser age, but from the tempestuous weather and the shower of abuse it daily received from its older companion. The mother eagle constantly disregarded the needs of its puny infant, but bestowed every attention on her more vociferous offspring. Thus, on May 18, when the eagle brought in a large fish, the older nestling got 76 pieces, but the younger only 2, and a bad drubbing from his nest-mate in the bargain. On the following day rain and hail beat so relentlessly on the great nest that this much abused eaglet, then hardly able to crawl beneath the sheltering wings of its mother, finally succumbed and was trampled into the great mass of withered grass that lined its bed. It should be noticed that this harsh treatment of the younger bird had often occurred when the parent was away and when there was no contest over the food.
Both parents bring food to the nest and both assist in feeding the young. Dr. Herrick (1929) describes the process as follows:
The female eagle has been brooding her callow young, which are now in white down and about two weeks old. She deliberately rises, walks over to the carcass of a large fish, stands on it and begins tearing off small pieces of the flesh and passing them to the three eaglets, which line up before her.
Twenty minutes later the male drops on the eyrie and immediately joins his mate in the work of satisfying the appetites of their hungry brood. The old eagles bend to their task and pass up bits of food at the rate of about five to the minute. At least the passes are at this rate, but the proffered food is not always taken. It may indeed go the rounds, to be eaten finally by one of the old birds.
When the eaglets are older and strong enough to tear up their own food, they are taught to do so. A family feast, presided over by the mother eagle, who has just arrived with a fish, is thus described by the same observer (1929):
Her young, all aquiver with excitement, continue to crouch and squeal, with their wings half spread, but they seldom venture to advance. The old bird now seizes her quarry, which appears to be a lake catfish of about four pounds in weight, and with one foot drags it to the center of the nest.
Standing on it there, she begins ripping it up without further ceremony. With swift thrusts of her bill she detaches large pieces of the white flesh and, taking a glance around at each upward stroke, swallows them in rapid succession. Then to the nearest bird, which by this time has edged up to its parent, she passes several pieces from bill to bill, and goes to work again on her own account.
When eaglet number two has been served in the same fashion, she moves a few steps away; whereupon number one seizes the carcass and, spreading over it, claims it as his own. Squealing, with head down, but for some moments without touching a morsel, he warns all intruders away. Meanwhile the other eaglet, drawing nearer, with head extended, watches the feeding bird and, seldom venturing to interfere, patiently awaits its turn.
We have noticed that this pair of adults is very adept at getting all three eaglets fed. They will first focus on the oldest eaglet, and they will feed it until it is gorged and literally cannot move. Then they move on to the middle one with the same technique. The third, youngest eaglet then gets fed, free from the abuse of its older siblings.
It is a rare thing for three eaglets to fledge, so these birds still have a challenging few months facing them.
Spring 2008 Update #1 - March 24, 2008.
We have had an extremely successful hatch, with three healthy young eaglets growing rapidly. The first eaglet was hatched in the wee hours of March 13th. The second eaglet was hatched on March 14th and the third on St. Patrick’s Day, March 17th.
We’re now into the growth stage where the eaglets are being fed every few hours. These eagles will mostly subsist on fish, but the adults will bring in whatever they come across. Dam number 4, right upstream from the nest has lots of spawning suckers and walleye congregating right now offering tremendous fishing for the eagles. Watch for a fresh fish delivery anytime on the live cam. As to other food, today there are the remains of a ground hog in the nest.
Winter 2008 Update #1 - February, 2008.
The eagles maintained their activity at the nest and after several weeks of mating activity, the first egg was laid over the weekend on February 2nd or 3rd. Unfortunately the cam was down that weekend, and when it came back up there was the first egg. The evening of February 6th, another egg was laid. There is a play-by-play description of the activities that evening on the NCTC Eagle Cam Daily Blog. Another egg was seen on the morning of February 10, making this a clutch of three eggs. The weather has been varied throughout this period, and there were several warm days where the eagles both left the nest and the eggs for a short period of time. There has also been a series of rain and ice events that have tested the pair's ability to keep the eggs warm and dry.
