(Eaglets eight weeks old)

As I mentioned on the cam page, we have picked the two winners for our 2008 Eaglet-Naming Contest. We have emailed the winners, but we haven’t heard back from both of them yet, so we’ll hold off announcing the names since we normally like to share a little personal info about our winners when we make the announcement. Thanks to all those who took the time to enter our contest and share their creative skills with us. We got a lot of great names.

As we noted earlier, we are hearing from staff and volunteers at the Refuge that the eaglets are tearing off food for themselves now, but we are still seeing shots showing the eaglets being fed by a parent. This could be a case where even if the eaglets can do it themselves, it’s just easier when mom does it.

Regarding the eaglets’ size, I’ve been watching the cam over the last week or so to see if we can tell the gender of our chicks now that they’re two months old. It appears to me that they both look about the same size, which seems to indicate we may have two of the same sex. In addition, I’ve been looking at how they compare to the female eagle (the bigger of the parents), and it appears that our eaglets are smaller than she is. We’ll never know for sure the gender of our two youngsters, but based on these images, we might hazard to guess that we have two males.

Branching Eaglets

The eaglets are now about eight weeks old, and it’s amazing how fast the time has flown and how big our youngsters have become. Bald eaglets normally fledge at 9-13 weeks of age, but before they take that first flight, they spend a good bit of time branching.

Branching is when the eaglets hop out onto the branches of their nest tree and perch there. This activity helps them develop their perching skills (remember they’ve been sitting in the nest all this time) and also gets them acclimated to maneuvering in and out of their nest and around the tree branches.

Our friend Woody Dawson, from up near Susquehanna State Park in Maryland, loaned me this animated GIF (975KB) that he made showing one of his local bald eaglets branching. Notice how the eaglet uses its wings to maneuver its talons along the branch. Once the eaglet is in a secure place on the branch, it will perch there and observe the world around its home nest.

We also have a branching video clip from our own cam. In this clip from last year, we see our eaglet Majesty flapping out to one of the branches under the web camera. Then later in the clip you see our other eaglet, Justice, flapping her wings and skipping along the nest — she was very close to flying at this point. Note that as a female bald eagle, her wingspan could have reached 6-7 feet.

5 MB

The loblolly pine tree that holds our web camera — and the eaglets’ home — has several branches for the eaglets to choose from. On our current camera view you can see one of the branches in the upper left corner. Also there is a big branch on the right and a third under (and to the left) of the cam — this is the branch Majesty used in the video clip.

We can’t move the camera (or zoom out) to see the branching, but I have asked our volunteers and staff at the Refuge to let us know if they see any branching from our live TV monitor at the Visitor Center. It’s easier to see the branching on live video because you can see the eaglets jumping in and out of the nest. I will be getting some new video from the Refuge soon, and I’ll be sure to share those clips here, but thus far we do not have any confirmed branching yet from our eaglets.

Thanks to everyone who has been sending in images for our Eagle Cam Gallery. We’ll post an update before the end of the week.

Until next time,
Lisa - webmaster
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Tags:
bald eagles, eaglets, wildlife refuge, eagle cam, branching, Blackwater Refuge, Maryland

 

Happy Earth Day to everyone!

The first Earth Day was celebrated on April 22, 1970, by 20 million people across the country, and every year since then concerned citizens in America have tried to mark this day as a moment to raise awareness about our environment. If you’d like to read about how Senator Gaylord Nelson organized the first Earth Day back in 1970, visit the Wilderness Society website for more information.

In honor of this day, I thought it would be a good time to talk about the interesting relationship that exists between eagles and ospreys — the two wonderful raptors that we celebrate with our web cams. Eagle and osprey populations in the U.S. were not always as healthy as they are today. In the post World War II years, large amounts of the insecticide DDT were introduced into their environment, and the poison affected the ability of eagles and ospreys to reproduce successfully — much in the same way that DDT in the waters off California is affecting the reproductive success of eagles in the Channels Islands today. The eventual recovery of eagle and osprey populations was greatly helped by the environmental awareness that grew out of events like Earth Day and the publication of Rachel Carson’s seminal book Silent Spring. In fact, DDT was banned in America two years after the first Earth Day was held.

Eagles and Ospreys

Blackwater National Wildlife Refuge is fortunate in that it has a large population of both eagles and ospreys, so confrontations between the birds here is not uncommon. Often when the two raptor species tangle, the battle is about fish. Ospreys are considered perhaps the best anglers in nature, and while eagles are also skilled at catching fish, they are better known for being opportunists that will sometimes use their larger size and greater power to steal a fish from an osprey rather than catch it themselves.

The bald eagle’s propensity for theft is what gave it a less than noble reputation in the eyes of founding father Ben Franklin. In a letter to his daughter, Franklin voiced his objections about the eagle:

“For my own part I wish the Bald Eagle had not been chosen the Representative of our Country. He is a Bird of bad moral Character. He does not get his Living honestly. You may have seen him perched on some dead Tree near the River, where, too lazy to fish for himself, he watches the Labour of the Fishing Hawk; and when that diligent Bird has at length taken a Fish, and is bearing it to his Nest for the Support of his Mate and young Ones, the Bald Eagle pursues him and takes it from him.”

Biologists today are not as critical of the bald eagle and recognize this fish-stealing habit as an effective survival skill rather than a moral defect. And the eagle does often find success because despite efforts on the part of the osprey to keep its fish, many accounts of the birds’ battles end with the osprey being forced to drop its meal. But if the osprey puts up a fight, then you might see something more dramatic.

In the book The Bald Eagle: Haunts and Habits of a Wilderness Monarch, one of the authors describes an event on a Saskatchewan lake that showed a surprising twist to the usual skirmish:

“The eagle attacked from a few feet above and to one side of the Osprey — once, twice, and then a third time. On each pass the Osprey visibly flinched, for the eagle’s talons barely cleared its back. We anxiously awaited the outcome. Many observers had described how typically the Osprey drops its fish, and with surprising agility the Bald Eagle snatches the fallen prey in midair. We were not prepared for what happened. After three unsuccessful attacks, the eagle turned to brute force. This time coming up fast from behind and below, the eagle flipped onto its back, thrust its talons upward, and ripped the fish right out of the Osprey’s grasp. What a sight! After quickly righting itself, the eagle turned and flapped leisurely to deposit the booty on its nest.”

During the times when the osprey comes out on top, it’s often because it outsmarts the eagle. For example, sometimes osprey couples will team up to protect their food from the eagles. Our Blackwater ranger, Tom Miller, witnessed this when he saw an osprey fly toward an eagle to intercept it while the osprey’s partner quickly flew to the home nest with the fish.

In addition, ospreys can be even more aggressive if they’re protecting their young and their home nest. At Pelican Island National Wildlife Refuge in Florida, local photographer Bob Montanaro captured this type of event on film as he watched a group of four ospreys drive off a group of immature bald eagles that were flying too close to the ospreys’ nests. Be sure to view these amazing photos where you can see the osprey aggressively flying at the immature eagle and making it clear that the ospreys will not tolerate the eagles in their territory.

At Blackwater, our ospreys at the Osprey Cam nest will react to bald eagles that are perched in the woods to the left of the nest. You can’t see these woods on the cam image, but it’s an area where eagles sometimes like to sit, and the close proximity to the osprey platform makes the ospreys agitated when an eagle is there.

A few years ago, I was at the Refuge with my video camera and was lucky enough to capture an episode showing the cam mother chasing off an eagle that was trying to perch in the trees near the cam. The first video below shows the eagle flying into the trees near our Osprey Cam nest and the other shows the mother consequently dive-bombing the eagle. In this instance, the mother did a good job of sending a strong message to the eagle, but it was somewhat risky for her to have to leave the chicks alone to do this. (Left-click on the Windows Media Video file links below to play, or right-click on the links and choose “Save Target As” to download to your computer):

Eagle Flyby (3.5MB)
Osprey Dive-bombing (2.5MB)

Just recently, photographer Bob Quinn was out at the Refuge and witnessed a similar episode between our Osprey Cam birds and an eagle that had been sitting in those trees. His photo (on the right) offers a dramatic glimpse at how these aerial battles look when a smaller raptor tries to take on a much bigger challenger.

Even with all the ospreys’ spunk and determination, there is no denying the fact that bald eagles are more powerful. A great example of this can be seen on a YouTube video I saw recently that shows a bald eagle taking a fish away from an osprey on Lake Merwin in Washington state. The speed with which the eagle overtakes the osprey is truly amazing to watch. The chirping you hear in the background is the osprey “yelling” at the eagle for stealing its meal. In such a situation, there’s not a lot the osprey can do but accept the fact that the eagle won this battle.

[A sidenote to teachers and parents — this video includes a slightly muffled profanity at the end by one of the observers in the video who got excited watching the scene, so just a little warning for the youngsters in our audience.]

Happy Earth Day!

Until next time,
Lisa - webmaster
Contact

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

 

(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