March 03, 2007
Welcome, Eaglets!
We have a lot to cover in this web log entry, so forgive the length of the post. First, a big congratulations to our parents on their two-eaglet brood! Both eaglets arrived on their 36th day of incubation, so here is the 2007 scorecard:
1st egg
Laid: 01/24/07
Hatched: 03/01/07
2nd egg
Laid: 01/26/07
Hatched: 03/03/07
Thanks to all our cam watchers who have been sending in photos of the events and emails of congratulations. We had a lot of photo submissions, so in Friday night's Gallery update, I spread the name credits around on the photos. We'll try to do another Gallery update in the next few days.
Some folks have asked about the size of a newborn. Newborn bald eaglets are about 4-5 inches in length, and weigh about 70-105 grams at birth, but will gain up to 180 grams a day. In fact, it's been stated that bald eaglets are the fastest growing birds in North America.
Also, cam watchers have asked about the terminology. Today the youngest eaglet is a hatchling and the older eaglet is a nestling. Beyond today, the two eaglets will be called nestlings until they learn to fly, at which time they'll be called fledglings. Then when they are flying about independently, they are called juveniles or immatures. Once they get older and closer to breeding age, they might be called sub-adults. And once they reach breeding age and get an all-white head and tail (about 4-5 years of age), then they are called adults. But right now, I mostly refer to them as chicks or eaglets.
The Family:
So far the parents have been good about bringing in fish for the eaglets, although at some point they might bring in other types of food too (ducks, etc). Whatever the parents eat, the eaglets can eat. The parents do not regurgitate the food like some other birds do. They tear off tiny bits and gently feed them to the chicks. It will be quite a while before the eaglets will be strong enough and big enough to tear off their own food.
Although we can't hear the eaglets, they are certainly chirping to express themselves and their needs. The Institute for Wildlife Studies in California has several videos on their website of newborn bald eaglets. Be sure to visit the Photos and Videos page and scroll down to look at the first few videos they offer -- those will give you a good idea of how our little eaglets look and sound in person.
You'll notice from the videos that the eaglets like to peck a lot. This is instinctive and starts almost as soon as they come out of the egg. They'll peck at almost anything -- food, fingers, their siblings. Pecking is the one thing they can do early and do well, so they do it a lot. :-)
Since our firstborn is about 48 hours ahead of the second chick, this means the firstborn has a definite growth advantage, since bald eaglets grow very fast. In fact they grow so fast, that years ago when biologists first started visiting eagle nests, they thought the eaglets were being born weeks apart since they varied so much in size. Turns out they were only one to three days apart.
So in our Eagle Cam nest, the firstborn will be the dominant chick and will likely pick on the younger chick, at least while they're small. This is life in an eagle nest -- the chicks have a hierarchy and being firstborn makes you king of the nest and means you get the most food. In an area where food is in short supply, this would spell trouble for the youngest eaglet. But Blackwater Refuge has a lot of food, so right now we would expect that both chicks will get enough food to survive, even if sibling rivalry means that the oldest chick gets fed the most.
As for the parents, they surprised us a bit during the first hatching. In the past two Eagle Cam seasons, we had a clear view of the egg as the hatching occurred. But this year, the mother stayed on the eggs almost the entire time, and then when the first chick hatched, she suddenly just stood up and there was a chick. It's possible the mother eagle decided to stay on the hatching chick since it arrived very early when it was still cold. For the second eaglet, we got a much better view because the mother was feeding the first chick while the second was being born.
The other surprise came right after the first eaglet was born. Normally the mother performs most of the incubation duties once a chick is in the nest and dad provides the early meals. But instead mom took off and left dad to watch the new youngster, and then she brought back the first meal -- a nice fish.
These surprises illustrate one of the most important lessons we've learned while watching our raptor cams for the last six years, and that lesson is that no animal is completely predictable. Although birds (and other animals) are largely driven by instinct, that does not mean that we can predict what they will do in every situation. Each bird is unique -- they have different personalities, different temperaments, different genetic attributes, and different levels of experience. They also react differently to their mates, to other animals, and even to people. So it's not possible to say "They will always do this." Instead we try to say "They will often do this" as we can only indicate what are the most common behaviors. But in the end, the birds' actions are not set in stone, and that is why it's so enjoyable to watch the raptors year after year, because each season is different in its own way.
Other Eagle Sites:
We've had several cam watchers post images from our Eagle Cam on their own sites, and I wanted to remind everyone to check them out. First we had Glo, who has now posted two slide shows of our eaglets on her For the Love of Eagles blog. Also, Paula (a follower of the NCTC Eagle Cam in West Virginia) has posted two movie/slide shows of our eaglets on her Eagle Momsters blog. Thanks to both of them for offering these entertaining views of our youngsters.
Speaking of the NCTC Eagle Cam, check out this shot of the poor mother eagle on the nest during our recent bad weather. And we thought our parents had it bad!
On a related eagle note: Our friend Kimmarie, who is following the Barton Island, Massachusetts Eagle Cam, has posted in her forum that the MA nest now has an egg. She has also just posted a video of the parents tending the egg, which you can see toward the bottom of this thread on her forum. In the past, Kimmarie has run the very interesting Buffalo, New York Peregrine Falcon Cam.
Cam Times:
I wanted to remind those who are new to the Blackwater Refuge raptor cams that both our cams will shut down from 11pm to 3am ET each evening. We do this because action at night is very light and because it helps us stay within the bandwidth limits that our satellite dish provider sets for us. So don't be concerned if the cams stop during those times.
Speaking of both cams -- don't forget that we expect our ospreys to return from South America around mid to late March. Once the ospreys formally reclaim the Osprey Cam nest, all the other birds should leave the platform (including the eagles), as the eagles will not normally challenge the ospreys for their home nest. The ospreys will be with us into early September, and once they leave, the other birds will begin visiting the platform again.
Pelicans:
And on a final note: As our cam watchers may remember, earlier this week on the Osprey Cam page I mentioned that we had a flock of white pelicans that had spent the last two winters at Blackwater Refuge, even though they normally winter much further south along the Gulf of Mexico. While our pelicans appear to be fine, we did hear this week that a group of immature brown pelicans was found in southern Maryland and Virginia but these birds were suffering from frost bite, and some did not make it. These birds should have migrated further south, but they may have become confused by the unseasonably warm December and January that we had, and then they got caught in the February cold and snow.
The birds are now with Tri-State Bird Rescue and Research, which is a wonderful local organization that comes to the aid of injured birds. Tri-State often rescues local eagles and ospreys as well, so we are indebted to them for the fine work they do. Tri-State is asking for donations to help the pelicans because the birds require a lot of food and care until they are ready to be released. You can find out more on the Tri-State website.
I plan to head out to the Refuge soon to capture some video of our two new eaglets in action. Once I have those video clips from the cam, I'll post them here in our web log.
Until next time,
Lisa - webmaster
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