it is more rare than you claim, and it is especially rare in this nest. which is what I am discussing .THIS NEST.
You claim that we better watch because one of these 2 eaglets will die in the next few weeks. You are making claims about this nest which are not correct. With everything else going on in this world and this being one refuge of beauty and calming why do you have to come in here and start telling everyone...oh look out in the next few weeks one will certainly die?
Here's some data that is against your claims. Now I'm done if you are done trying to be always right about everything.
Siblicide in Bald Eagles
The wide discrepancy in opinions about Bald Eagle siblicide got my deeper attention recently when I was advised that I was wrong about it being rare, that it is in fact quite common. I awoke early one morning on a mission to find out the facts.
There wasn't much on the internet ...
University of Nevada, Chronicle of Higher Education: "Many animals engage in the fraternal/sororal equivalent of homicide, namely siblicide, whereby siblings kill each other. And bald eagles are siblicidal."
The American Bald Eagle Foundation: "Two eggs usually hatch in each Bald Eagle nest, but, often due to siblicide, only one eaglet will survive."
The Sutton Avian Research Center in Oklahoma: "At the Sutton Center, we hatched and raised nearly 300 bald eagles over an eight year period. As soon as the down of hatching chicks had dried, most chicks almost immediately began attacking other "just hatched" chicks vigorously by "hammering" with their beaks, grabbing on, and shaking. They had to be separated physically to prevent siblicide during that period. We concluded that in the wild, the only thing that kept them from killing each other as hatchlings was the physical presence over them of their brooding mother, or in our case, a folded towel."
Hornby Eagle Group Projects Society, FAQ on sibling aggression:
"The older bird is larger, heavier, and more developed than the younger bird, so it requires more food and is avid for its share. Siblings will thus compete for food and parental attention, with one bird attempting to out-compete or dominate the other. The younger bird soon learns to keep a low profile until the older has been satisfied and quickly learns to use its wits, making grabs for food or doing 'end runs' around the larger bird. This behaviour occurs more within the first two weeks of life, declining as the siblings learn. Siblicide (one eaglet killing or causing the starvation of another) appears to be rare in bald eagles."
All of these were opinions and conclusions, and "common" seemed to be the general agreement regarding siblicide in Bald Eagles. But there was that "rare" of the HEGPS site, written by Ajl, whose opinion I knew was based on close observation of wild birds in their nests, rather than speculation, hearsay, ground observations, old books or the behavior of captive birds.
It's quite possible that chicks raised in captivity without the guidance and comfort of their parents might be more aggressive than chicks with dad or mom nearby, even with plenty of food for all. But the eaglets I have observed on webcams have alternately demonstrated both aggression and affection toward each other. And I have seen the Decorah Eagles' mom step into the middle of a three-way fray and put a stop to it. I have seen eaglets die, from illness, neglect, storm, etc, but I have not seen an eaglet actually kill a sibling, although I am aware that it happens. On BRI's eagle webcam nest in 2012, there was a significant lack of food, the parents were strangely absent, and the younger eaglet was driven to the edge of the nest where he subsequently fell off and died. And why not? "If only one of us is going to survive, it will have to be me, because I'm already bigger and stronger ... I'm sorry, I need to kill you or we'll both die."
And then I did more research. I studied 62 webcam Bald Eagle nests with direct observations of the nest bowl recorded over a period of up to 8 years. The total number of nest seasons was 240. Of that number, there were 91 with just one hatch or none, 105 nestings with 2 hatches, 42 with 3 hatches and 2 with 4 hatches. (These are all direct observations of egg-laying, hatch, eaglet development and fledge.)
Of the 105 nestings with 2 hatches, both eaglets successfully fledged 77 times (73%), 1 eaglet fledged and 1 died 22 times (21%), and both died 6 times (6%). Of the 34 who died, the cause of death was parent neglect (6), killed by intruder (4), storm (4), failed in the first day or two (3), accident (5), illness (1), unknown (7), possible siblicide (1), and known siblicide (3). Based on these figures (including the possible siblicide), the incidence of siblicide on a nest with 2 eaglets is 3.8%.
Of the 42 nestings with 3 hatches, all 3 eaglets fledged 35 times (83%), 2 fledged and 1 died 3 times (7%), 1 fledged and 2 died 2 times (5%), and all three died 2 times (5%). Of the 13 who died, the cause of death was storm (eight), poison (2), accident (1), unknown (1), and siblicide (1). Based on these figures, the incidence of siblicide on a nest with 3 siblings is 2%.
Of the 2 nestings with 4 hatches, all 4 eaglets successfully fledged on one, and 2 on the other. The cause of death of the 2 who died was storm (1), died in the first day or so (1).
The known incidence of siblicide on these 62 random nests of 396 hatched eaglets was 4 eaglets, 3 of whom were from the same nest in Maine, and all were attributed to lack of food and/or parent neglect. That's 1%. It would be less than 0.3% if I discounted that one nest in Maine.
So there are some facts and figures to back up anyone who wants to help dispute the myth that siblicide in Bald Eagles is common, that they 'do it all the time'. They don't. As Ajl says, it "appears to be rare".