(Chicks six weeks old)

Eaglet-Naming Contest

Although we’ve mentioned it on the cam page, I also wanted to announce here that we have now started our 2008 Eaglet-Naming Contest. Visit our Contest page for all the details you need to enter, and remember that the window for entering your names is two weeks, so the contest will end on April 26.

Eagle News
The Barton Island Eagle Cam in Massachusetts now has two chicks. Our friend Kimmarie at Falcons and Friends has posted an entertaining video of the first hatch, which you can see here.

Also, our friend Bobby from Kentucky alerted us to the hatching going on at the three-egg nest on the Colorado Eagle Cam. Here’s a great capture of the first hatching.

Raptors and Lead Poisoning

About a week ago, an event regarding a bald eagle came to my attention, and I’d like to talk about it here with the hope of producing some good out of an unfortunate situation.

One of our cam watchers was with his wife near Vienna, Maryland, which is not far from Blackwater Refuge on the Eastern Shore of Maryland. He spotted an adult bald eagle in a tree, and at first he thought the eagle looked very old, since the eagle was listless but with no visible signs of injury. He wrote me when he got home and sent me the photo you see to the right. I forwarded the photo to a volunteer with Tri-State Bird Rescue and Research, which is a wonderful bird rehabilitation outfit on the Eastern Shore. Before anyone could go out and look for the bird, a representative from the Maryland Department of Natural Resources brought a female adult bald eagle to Tri-State, and it had come from this same general area, so we suspect it was the same bird.

The Tri-State vet discovered that the eagle was dehydrated, anemic and underweight. The in-house lead test they performed on her was very high, and radiographs showed seven discrete metal densities in her ventriculus (gizzard) and the pellets appeared to be lead shot. The vet started treatment, and they saw hopeful signs at first, since the eagle was trying to stand, but after a couple days of treatment, she died — the poisoning was just too far along.

This sad event brings to light an important issue in the avian world — lead poisoning. According to the website Wildlife Without Lead (which was created by HawkWatch International):

Raptors may scavenge or prey upon birds, mammals, or fish that have been exposed to lead, resulting in the risk of secondary lead poisoning. This became strikingly evident in the summer of 2000 when five of the captively-bred California Condors reintroduced into the Vermilion Cliffs area of Arizona died from lead-poisoning. It is believed they ingested lead shot from a mule deer carcass.

Any raptor species that forages on game animals is at risk of secondary poisoning including Golden and Bald Eagles, California Condors, and accipiters such as Cooper’s Hawks and Northern Goshawks. Digestive acids wear down the leaden material which is then absorbed into body tissues. When lead enters the circulatory system, it mimics the movement of calcium. It becomes stored in the bones and some may be excreted into the feces via the bile. Eventually, concentrations may reach toxic levels causing a variety of problems which often end in death…In many birds, sub-lethal dosages present a variety of symptoms. These include immune suppression, reproductive impairment, weight loss, wing droop, diarrhea, and tissue damage. Many of the sub-lethal problems result in death due to reduced physical performance, susceptibility to disease and infection, and increased predation.

And raptors aren’t the only birds affected. Other birds susceptible to lead contamination include: Common Loon, Trumpeter Swan, Mississippi Sandhill Crane, Canada Goose, Mallard, American Black Duck, Ring-necked Duck, Redhead, Wood Duck, Greater Scaup, Common Merganser, Red-breasted Merganser, White-winged Scoter, Sandhill Crane, Great Blue Heron, Common Egret, Snowy Egret, White Ibis, King Rail, Clapper Rail, Herring Gull, Laughing Gull, Royal Tern, Brown Pelican, American While Pelican, Double-crested Cormorant.

As for how an eagle could become poisoned, the Raptor Center at the University of Minnesota reports that:

When lead fishing sinkers are lost through broken line or other means, birds such as loons, swans, and eagles can inadvertently eat them. Some birds swallow lead when they scoop up pebbles from the bottom of a lake or river to help grind their food; others ingest lead by eating fish that have swallowed sinkers. When lead ammunition is used in the hunting of large game, and gut piles are left behind or the animal is wounded and dies later, eagles can swallow a piece of shrapnel as they scavenge on the remains of the dead animal.

Although it’s difficult to get accurate statistics on casualty rates from lead poisoning (since many poisoned animals are never found), the Center states that “Between 1980 and 1996, The Raptor Center at the University of Minnesota reported lead poisoning in 138 of 650 eagles treated by the Center. Since 1996, an average of 25 percent of the bald eagles admitted to The Raptor Center each year have toxic levels of lead in their blood.”

In 1991, the use of lead shot for waterfowl hunting was banned in the U.S., and just recently California responded to the threat of lead poisoning in Condors by making hunters switch to non-lead ammunition when they hunt big game and coyote in Condor habitat. While both these acts were important steps in the battle to reduce lead poisoning, lead is still the primary material for ammunition used to hunt mammals and upland birds and for weights used to fish.

What You Can Do

If you have a friend or family member who hunts or fishes, then pass along the two brochures provided below to these people. Show them what the consequences of lead poisoning can be and show them that they can make a difference by avoiding lead-based materials. Included in the brochures are tips for finding non-lead products at local retailers.

If you hunt or fish yourself, consider the many species you are inadvertently hurting with your use of lead and make plans to switch to non-lead products. In addition, it’s also important to dispose of the lead products you currently have by taking them to your household hazardous waste facility for proper disposal. Finally, you can help by patronizing retail stores that promote and sell non-lead products.

We can’t do anything now to save this bald eagle that was poisoned, but we can do something to save the many other birds that might die in the future. So take a moment to alert those around you to the dangers of lead, and encourage them to find alternatives that they can live with — and that our wildlife can live with, as well.

Until next time,

Lisa - webmaster
Contact

Tags:
eagles, wildlife refuge, raptors, lead poisoning, Blackwater Refuge

 

(Chicks: four weeks old)

First, I wanted to make a quick announcement about Earth Day (officially April 22). In honor of Earth Day, Blackwater Refuge will be holding a litter pick-up on April 12 and also a tree planting on April 27 and May 3. If you’d like to celebrate Earth Day, this is a great way to do it — for individuals, families, and community groups. The litter pick-up not only helps make the Refuge more attractive, it helps reduce roadkill (animals are attracted to the trash); and our tree planting will help restore vital habitat at the Refuge. So visit our Earth Day page to learn more about joining us and giving something back to nature.

Eaglet Update

Our eaglets are doing well and growing more each day. We’ve recently seen the mother eagle bringing in a little more food, and both chicks seem to be getting fed, although it’s clear the older eaglet is getting the most.

Right now the routine seems to be that when the mother brings a meal, the older eaglet asserts its dominance and the younger eaglet acts submissive. But then once the older eaglet is full, the younger bird steps forward and gets fed. As an indication that the eaglets are getting fed, we’ve noticed we can now see their crops after a meal. A crop is a pouch on the chest area of each eaglet and it’s used for storing food for later consumption. So when you see an enlarged crop, it means the chicks have been given a decent meal.

We’ve had folks ask what the eaglets look like up close, and this photo is about the best look we can give you. This is an eaglet with the second coat of down and also with a few new blood feathers (on its lower right wing). Both of our eaglets are showing signs of blood feathers (dark brown areas on their bodies, especially on the tips of their wings and their backs), so they look a lot like the bird in the photo.

Another question we’ve been asked is whether or not the eaglets are feeding themselves. It is possible at this stage that the eaglets are tearing off some food themselves, although they are still reliant on the mother for a good bit of the feeding. But it won’t be long before the eaglets will be able to tear into a fresh meal themselves.

Miscellaneous Eagle News

Before we get to our new videos below, I wanted to share some miscellaneous eagle news. Biologists in California are helping the eagles in the Channel Islands recover from the lasting impacts of DDT (the banned pesticide), and one way they do this is to remove eggs from eagle nests on the island and manually incubate them, then put the chicks back into the nest once they’ve hatched. They do this because DDT that was dumped into the California waters decades ago still weakens the eggshells of the raptors. Here is an amazing video of two of the incubated eggs, and in the video you can hear what the eaglets sound like right before they hatch. Keep in mind this is the sound the eagle parents hear, which lets them know that the chick is coming. Very cool!

Videos at Three Weeks of Age

About a week ago, I was given some new videotape of our eaglets. These clips show the young birds at about three weeks of age, and they were recorded from our live video feed, which you can see on the monitors at our Visitor Center. You can left-click the videos below to play them or right-click and choose “Save Link As” or “Save Target As” to download them. Also, you can see these videos on our Blackwater YouTube Channel.

In the first video, we see one of the eaglets flapping its wings. This is just the beginning of what will be many hours of flapping practice as the young birds try to develop their wings for that first big flight.

5 MB

In the second video, we see the father eagle arrive with what looks like a small mammal. The mother takes the father’s offering and prepares to feed the eaglets. This video gives us a nice view of one of the somewhat rare times when the family is all together.

5 MB

In the third video, we see one of the eaglets slicing over the edge. Slicing is the falconer’s term for defecating, and chicks know at a very early age to back up to the edge to relieve themselves. (This is why you see whitewash on many of the branches around the rim of the nest.) Also in this video we see the same eaglet using its talon to scratch its face.

6 MB

And in the final video, we see a funny episode where the older eaglet tries to swallow a very long bone — which doesn’t seem like such a good idea to the mother — and eventually the young bird has to cough it up.

6 MB

Osprey News

Tom Lorsung recently sent in a beautiful photo taken at one of the water osprey platforms at the Refuge. In addition to our land-based Osprey Cam nest, the Refuge also has several water osprey nests that you can see from our Wildlife Drive, like the one in Tom’s shot. So even if our cam nest action is erratic, we are getting regular action at our other nests.

Also, I wanted to share this amazing video from the Puleston Osprey Cam in New York where the male osprey delivered a fish to the female. Only problem was the male had a hard time removing his talon from the meal, and the female flew away with the fish while he was still attached to it! We hear the male returned to the nest later, so he was all right.

As for our nest, as we mentioned on the cam page, we appear to have three ospreys (some cam watchers think four ospreys) vying for the cam nest. We’ll just have to wait and see if one pair claims the nest and begins refilling it with sticks. We had an odd year on the cam last year, and it appears this year will be unusual too.

A final note: One cam watcher asked about when I’ll start the Osprey Cam Web Log. I’m waiting to see if we’ll actually have a nesting pair on the platform before I start the web log. But in the meantime, for those who want to learn more about ospreys, be sure to visit our Osprey fact page, and also visit our Cam Central page to find links to our old Osprey Cam Web Logs. The 2006 season was particularly rewarding as we had four chicks hatch on the platform that year, and all of them fledged — a somewhat rare occurrence for a North American nest.

Until next time,

Lisa - webmaster
Contact

Tags:
eagles, wildlife refuge, eagle cam, eaglets, Blackwater Refuge, Maryland

 

Our eaglets are growing rapidly, and it looks like they now have their second coat of darker, heavier down. We also see that the eaglets are able to sit up more and move around a bit. In fact, our younger eaglet moved so much the other day that I got a ton of emails asking if it had left the nest! Fortunately, the eaglet had just moved to the far bottom of the nest (near the trunk of the tree) and out of our view. The eagle parents seem to like perching in that area occasionally, and that may be why the chicks sometimes wander down there as well.

As for the eaglets, we see that they’re more comfortable at being uncovered in the nest. The mother eagle only seems to cover them when it rains or when the temperature is very cool in the early morning or evening. Otherwise, the eaglets are left uncovered, but we suspect one of the parents is sitting in the tree watching them, even if we can’t see them on the cam. Once the eaglets are big enough to be safe from predators, the mother eagle will be able to leave the area for longer periods and possibly do more hunting. We hope that will increase the food supply.

As for the father, we have no idea what he does with his time since we see so little of him. As we noted on Thursday, he did show up on that particular day with a fish or two, which was the most we’ve seen from him in a while. He seems to like spending time perching on the Osprey Cam nest, but other than that, he is only visible for brief periods during the day. We hope he is defending the nest area from intruders or sharing in the eaglet-watching duties.

Cam watchers have asked if this is our same pair from last year. Again, we don’t really think so based on their performance. It’s possible one of the pair died during the off season, and the other mate had to find a new partner. Or it’s possible something happened to both our eagles, and this is a completely new pair. Eagles are normally very loyal to a successful nest (which this one is) so we think if our former pair could have returned, they would have.

It is possible this is a new male, which would account for his lackluster performance. Maybe he’s just inexperienced at the responsibilities necessary for being a father — the main one being bringing in enough food for the eaglets and the mother during these early weeks of nesting. But we can be optimistic and say that at least the eaglets seem to be getting enough food to grow, and we hope as the mother becomes less tied to the nest, she might be able to roam farther in search of food, and that will increase the quantity of fish and fowl that we see.

Big Yellow Talons

One of the most noticeable traits on the eaglets now is their big yellow talons or feet. Beaks and talons grow fastest on young bald eaglets, and by about mid April, their beaks and talons will be close to adult size. Biologists speculate that this helps the eaglets because the full-size beak aids them in feeding themselves and the full-size feet help them hold on tightly to the nest when they’re moving around their home during windy weather or when flapping their wings in practice for eventual flight.

The eagle’s talons are comprised of four powerful toes that can break through tough fish skin or animal skin and then hold tight while carrying the prey home. These talons are similar to the osprey’s in that they both have tiny spicules on the toes (spicules are little bumps that help the raptors hold onto slippery fish). But the osprey has one advantage that the eagle does not have — an opposable toe. One of the osprey’s front toes can rotate backwards so that two toes are holding the fish from the back and two from the front. An eagle can only hold the fish with one back toe (called the hallux). This means an osprey has an easier time holding onto a thrashing fish.

Something else worth noting about the bald eagle’s feet is that the feathers do not go all the way down the leg (called the tarsus), unlike a golden eagle, which has a fully feathered leg. The reason for the difference is that the bald eagle’s primary diet is fish, whereas the golden eagle’s diet is primarily birds and small mammals. The bald eagle’s lower body often gets wet during fishing, so in order for its legs to dry faster and to reduce drag in the water, the legs, or tarsi, are bare of feathers.

Check out this graphic to learn more about the legs and talons of a bald eagle.

Osprey Update

For those who have been watching our trials and tribulations at the Osprey Cam, this is what we know: the fish in the Blackwater River (which is where most of the Refuge raptors fish) should have plenty of gizzard shad and catfish for our local birds. Also, from what our local experts believe, the owl and eagle that we’ve seen perched on the platform at different times would not likely prevent the ospreys from nesting at the platform.

In the past seven years of our Osprey Cam, whenever an osprey pair showed any intention to nest at the platform, the eagles vanished, so we don’t think a periodic eagle perched there is discouraging them if they really wanted the nest. The Great horned owl can be a predator of osprey chicks, but we’ve been told it is not likely the bird is discouraging the ospreys from nesting at the platform.

In the past, the ospreys have had great success at the Osprey Cam nest up until last year. As our old-timers know, 2007 was the first time in seven years of being online that we did not have chicks at the Osprey Cam nest. An intruder female osprey managed to disrupt the family structure, and our father went missing (possibly tempted by the new female), leaving the resident female on three eggs. She stayed with them as long as she could, but eventually had to get food, and while she was gone, a crow came in and punctured all three, thus ending our season.

When an eagle or osprey couple fail at producing a brood, they will sometimes change nests or partners, so it is possible our pair separated or chose not to nest again at the platform for that reason. Despite this, the Osprey Cam nest is a wonderful nesting location. It’s safe from land predators, it’s high and open (like ospreys prefer), and it’s right in front of the river, so we hope that another pair will take it, since we have a lot of ospreys arriving at the Refuge now for nesting season.

If you’d like to see what’s around the Osprey Cam, check out this web log entry I posted back in 2006. Scroll down the page a bit and you’ll see the 360-degree virtual reality Quicktime movie I put together that allows cam watchers to see what’s around the cam including the Blackwater River and the water impoundment areas that surround the nest. This movie also gives you a good idea as to the beautiful habitat that you can see if you visit our Wildlife Drive at the Refuge.

Eagle Audio

Finally, I did want to point out one more new video at the NCTC Eagle Cam blog. They have sound on their cam, and in the clip on this page you can hear not only the adults calling but also the three growing eaglets and their more developed whistles. It’s really a treat to hear the audio.

We’ll try to update the Gallery soon, and I just received a couple more videotapes from the Eagle Cam, so I’ll try to edit them and post some new YouTube videos within the next few days.

Until next time,

Lisa - webmaster
Contact

Tags:
eagles, wildlife refuge, eagle cam, eaglets, Blackwater Refuge, Maryland