May 04, 2007
Justice and Majesty
First, I wanted to remind everyone that we posted our official announcement with the results of our Eaglet-Naming Contest. Our eaglets are now named Justice (older eaglet) and Majesty (younger eaglet), and we know that they will both live up to their inspiring names.
Our eaglets are a little over nine weeks old and it appears from the cam photos that at least one of the chicks may be spending some time out of our sight while it perches on one of the tree's branches -- a raptor behavior known as "branching." This activity will increase over time and is a precursor to the eaglet's first flight. Normally eaglets fledge at about ten to twelve weeks of age, although the younger bird might take a little longer than the older bird. Last year our first eaglet flew in mid May.
One of our cam watchers sent in a question without an email address for replying so I'll answer that question here as it relates to this topic -- she asked about parents teaching the eaglets to fly. Parents do not have to teach eaglets to fly -- they know how to fly by instinct. That is why biologists can transplant eaglets to an area that does not have a healthy breeding eagle population (known as "hacking") so they will become imprinted on the new location and return there to breed. When they go to these new locations, they do so without their parents but are still able to fly, as well as hunt and fish.
The eaglets will know how to fly on their own, but once they are flying, they will have to practice to get better at it. This is especially true regarding their landing skills. Eaglets are notorious for making poor landings in the earlier stages of their flying careers, with observers having seen eaglets hanging by one foot, upside down, from a branch because they misjudged the landing. But the eaglets will get better at landing -- and also at manipulating the wind -- as they spend more time out of the nest.
Also there is the risk that an eaglet will not survive its first flight. We have not had this happen on the Blackwater Eagle Cam, but sometimes an eaglet will leave the nest and encounter trouble, or will leave prematurely and then not be able to get back to the nest safely. Bad weather, land predators, and hazardous landings can all make the first flight a risky one.
A couple of cam watchers have also asked about the eaglets' size. Now that our eaglets are almost fully grown, I think we can safely say that Justice appears to be female and Majesty appears to be male. When the eaglets lie together in the nest, it's clear that Justice has a longer body -- indicating she is female. I had mentioned back at the beginning of the season that a study done in Canada showed that the majority of first eaglets are female, so it appears our nest is in keeping with that study.
Female bald eagles can be around three feet in length, so that gives you an idea as to how big our older eaglet is getting. Also, once the eaglets' feathers are fully grown, they will actually be a bit bigger than the adults for a period of time. The reason for this is that immature bald eagles have longer feathers than their parents; biologists speculate that the reason for this is because young birds tend to do more soaring than the adults (possibly as a means of searching for food and also possibly as a result of being inexperienced flyers) so the longer feathers are more beneficial to the young birds.
Fully grown eaglets can be a challenge for the adults since they are big and potentially aggressive, especially when it comes to mealtime. Biologists have noted that the father eagle (who is smaller) does not spend as much time on the nest as the mother eagle in the latter stages of nest life since the aggressive eaglets can be harder for him to interact with.
What To Look For:
In the next couple weeks, we'll be looking for signs that both eaglets are branching -- unfortunately this means we'll lose sight of them on the cam, but it's a good thing because it means they are doing what eaglets were meant to do. We'll also be looking for signs that the eaglets are roosting in the tree at night with their parents rather than lying in the nest; this will be another sign that the young birds are becoming much more comfortable out on the tree limbs.
Once the eaglets have taken their first flight, we'll be looking for photos showing them landing in the nest or possibly taking off from the nest edge. Justice will likely fledge first, so that means Majesty will be left behind to watch his bigger sibling flying in and out with the parents. This will undoubtedly encourage him to join in on the fun as soon as he's able.
Catching a meal will be another major skill that the eaglets will have to learn, and it's a vital skill. Most of the eaglets that perish in their first year will die of starvation since finding food is not always easy. This is the reason why eagle parents nest so early -- it gives their eaglets more time to learn how to hunt and fish before the next winter arrives. The better the eaglets are at catching or finding food, the more likely they will survive.
So after the eaglets are flying, we'll be looking for signs that the eaglets have found their own food. An eaglet might appear alone in the nest with a dead fish or a half-eaten piece of prey. Young birds will often focus on retrieving dead animals in the beginning of their hunting careers because these types of prey are easier to find and because it will take a long while for them to get skilled at catching live fish. As with flying, the eaglets' instinct will help them with hunting and fishing, but they will also likely pick up tips by watching their family members look for food. Some immature eagles have even been seen tandem hunting with a sibling.
Probably around mid July, we will be seeing very little of the family because the eaglets will be getting more and more independent. They'll be spending large amounts of time exploring the Refuge, perching in trees, watching their parents and sibling fish and hunt, and roosting in the trees at night. At that point we will turn off the Eagle Cam since very little wildlife (a rare songbird or squirrel) will be seen at the nest with the eagles gone.
The parents will watch over the eaglets for about four to six weeks after they fledge (maybe a little longer if one eaglet is a slow learner), but then the young birds will strike out on their own. In a future web log, we'll talk more about what immature eagles in the Chesapeake Bay region do and where they go when they become independent.
As a special treat, I'm posting an animated GIF file (680KB) showing an immature bald eagle catching a fish. This clip is courtesy of our good friend, photographer Woody Dawson. Note the skill required for the young eagle to see the fish from the air and also time the strike just right in order to nab the moving meal -- and doing all this while in flight. This is what young birds must learn to do regularly.
Miscellaneous News:
Some additional raptor news I wanted to pass along: Three peregrine falcon chicks have hatched in San Jose, California where they reside in a nest at City Hall. Here are two sites that are covering the exciting action:
City of San Jose
Santa Cruz Predatory Bird Research
Also, one of our faithful cam watchers from Holland has provided us with an Eagle Cam link that shows a white-tailed eagle couple, which is famous in the area because last year they raised the first white-tailed eaglet seen in the Netherlands. This year the couple is back and has one chick. You can watch the family live on the Eagle Cam site.
Note: The white-tailed eagle is the largest European eagle, and is the closest relative to our American bald eagle.
And a final reminder that there are a few Bald Eagle Cams here in the US that still have chicks including ones in Virginia, Massachusetts, Washington State and Colorado.
Until next time,
Lisa - webmaster
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