May 29, 2006

Eagle News

nightfamily.jpgNest Update: Well, since the 2005-2006 eagle season has had a bit of everything, it only seems fitting that just as our cam reception improved, Murphy's Law decided it was a good time to have one of the birds move the cam for us. We are now looking out into the woods more. The upside is that now maybe we can see one of the eaglets coming in for a landing.

Speaking of the camera reception, it has cleared up a bit on its own recently. We had an engineer out to look at our reception problem late last week, but the engineer was stumped as to what was wrong. Right now we believe it might be a problem in the power line that runs near the nest. If there is a cracked insulator, loose wire, loose hardware etc. at the power line, it could be emitting intermittent noise that is interfering with our reception. We're currently investigating the power line theory.

When our cam did clear up, we got some nice images of both eaglets and probably the mother eagle at the nest. It was clear from the shots that the parents are still providing food to the eaglets. This is normal, as it will take awhile for the eaglets to get proficient at catching their own meals. We're happy to see that both eaglets appear to be healthy.

And just a couple extra cam notes: The Fort St. Vrain Eagle Cam in Colorado has three eaglets that are about to fledge. You can see the cam here. And here you can see photos of the eaglets when they were on the ground getting banded.

And also be sure to check out the impressive Eagle Eye Cam from Canada that has been capturing headlines with its wonderful video and audio presentation.

Also, I wanted to pass along some miscellaneous eagle news:

First, the sad news. Doug Bentlage from Alton, Illinois, wrote to say that they found out what happened to the eaglet that died in their local nest. As our cam watchers may remember, I had been publishing photos of their eaglet in this web log, and the last we heard was that the eight-week-old eaglet had suddenly been found dead at the bottom of the nest tree about two weeks ago.

The local photographers have just found out that a raccoon climbed into the nest and killed the eaglet. The raccoon got into the nest and killed the chick quickly, then an eagle parent came back and attacked the raccoon, and then grabbed the eaglet -- which was already dead -- and dropped it as it tried to leave the nest. The raccoon went over the front of the nest and then down to the ground. One photographer, named Tim Berkley, happened to be on the scene when it happened, but could only grab a quick shot in the fading light. Photographer Wade Dowdy (from Aesthetic Photos) worked on the photograph to make it clearer, and you can see the photo here. The raccoon is fleeing and the parent is flying away with the dead eaglet under its body. This was a very popular nest in Illinois, and many people were saddened by the loss of the eaglet, but at least we now know what happened.

One other piece of sad news: As we had mentioned a little while back, officials in Vermont -- which had been the only state without a breeding pair of bald eagles -- had discovered an eagles' nest with one chick near the Connecticut River. We now hear that the chick has died. A wildlife biologist discovered that the chick was gone, and they found evidence at the base of the tree that a raccoon had been feeding on a dead eaglet, although they're not sure if the raccoon killed the eaglet or if it was just feeding on the carcass. Local officials are hopeful that the eagle couple will return next year and try again. You can read more on the Vermont Bald Eagle Restoration Initiative website.

Just an FYI: Raccoons are a threat not only to eagle nests but also to osprey nests. That's why our Blackwater Osprey Cam platform is so high in the air -- so the ospreys will feel safe from land predators like raccoons. If you are building an osprey platform on land, it is very important to put a predator guard on it to reduce the chance that a raccoon can climb up and get to the eggs or chicks.

And now for the good news: For those who did not see my post on the cam page last week, George and Martha (the Woodrow Wilson Bridge eagles) have been reunited. Martha was attacked by a female eagle at her home nest in Maryland and had to be rehabilitated due to her very serious wounds. She was released in Delaware, and now the couple is together again at their nest in Maryland. TriState Bird Rescue was responsible for saving Martha. Visit their site for more information on Martha's release.

Also, we had another interesting local story about two young eaglets in Virginia that were saved after their tree and nest were blown down by a storm. You can read the article and see their photo on the Washington Post website.


Until next time,
Lisa - webmaster
(contact)


Posted by Webmaster at 07:10 PM

May 23, 2006

Second Fledgling

eagletpair.jpgNest Update: Congratulations to Waiwash! Our youngest eaglet appeared to fledge Sunday night, just as our first osprey chick was entering the world.

On Sunday evening, we could tell something was different at the eagle nest because the youngest kept appearing and disappearing, in and out of our cam image, often showing up with his wings spread. At one point, Waiwash was gone for a while, so we gathered the eaglet had become a fledgling.

Since that time, we've seen both chicks together in the nest, and we've also seen the mother feeding both eaglets, so it looks like the family is doing fine at this point and there have been no flying accidents.

As for our bad reception problem on the camera, we're now seeking professional advice as to what the problem might be. We tried several additional fixes on the ground, but they did not help, as this is turning out to be a mighty stubborn problem. Fortunately it came at the end of the eagle season and it is not affecting the osprey camera.

I also have an announcement for the local Marylanders who read our web log: On April 26, a badly injured bald eagle was found at Church Creek (a small town near Blackwater Refuge). The eagle had been shot and had a broken wing. The veterinarians at TriState Bird Rescue and Research in Newark, Delaware, determined it was a five-year-old female. The eagle's injuries were so severe, the veterinarians had to euthanize it. The U.S. Fish and Wildlife Service is offering a reward of as much as $2,500 under the Bald and Golden Eagle Protection Act for information leading to the conviction of the individual or individuals involved. If you have any information that might be helpful in tracking down the responsible parties, please contact Kim Speckman at 410-962-7980, extension 224. Kim is the FWS resident agent-in-charge of the Service's Baltimore office.

eg_eagle_sm.jpgOn a happier note, I wanted to share an entertaining story submitted by Elizabeth Gordon and her husband, Norm, regarding a recent visit they made to Blackwater Refuge. Elizabeth reports that during their visit, they were watching a Great blue heron that was hunting for fish. The heron made a catch and then brought the meal back to land. Suddenly an eagle appeared overhead and began eyeing the heron's catch. Knowing that it was "out gunned," the heron abandoned its food. The eagle landed, found the fish, and quickly flew away with the heron's catch. A few moments later, the heron began fishing again a few yards from the first hunting location.

Here is a photo that Elizabeth took of the eagle maneuvering over the heron before it lost its meal. Also if you've never seen a Great blue heron, here is a photo that Norm took of one while they were at Blackwater. Great blue heron's are the largest herons in North America, but there have been reports of bald eagles making a meal out of the birds, so the heron was wise to give up the fish without a fight.

Thanks to Elizabeth and Norm for sharing their story and their photographs. And also thanks to those who have been sending in images from the Eagle Cam. We'll update the Eagle Gallery later this week.

Until next time,
Lisa - webmaster
(contact)


Posted by Webmaster at 07:58 PM

May 18, 2006

Fledgling Explorer

Nest Update: First, I want to share some news from Jerry McKenna -- our photographer friend who had been following the one-chick eagles' nest in Illinois and whose photography I have been posting in my web log.

Jerry told me this morning that the eaglet has perished. Nest watchers found it at the bottom of the nest tree. They're not sure what happened at this point, but the 8-week-old eaglet was getting big, so there's a possibility it was flapping and was blown out prematurely. Or possibly it just fell out while leaning or standing on the edge. Jerry said they've been having strong winds lately. This was very sad news for us here, as we felt like we knew the eaglet through Jerry's amazing photos.

Unfortunately, this drives home the lesson that it's a dangerous world out there, and many eaglets perish before they can become white-headed, breeding adults. This also makes us appreciate the success we've enjoyed at our Eagle Cam, where we've had two seasons without any deaths. We're very fortunate in that regard.

Below is a final photo of the eaglet (click on the thumbnail). You can find more fantastic photos at Jerry's online gallery, and also at the online gallery of Doug Bentlage, a friend of Jerry's and another talented photographer who was also following the same eagle family. Thanks to both of them for offering this lasting record of the eaglet's brief life.

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As for our eaglets, it appeared that Monday night one of the eaglets -- probably the oldest, Nause -- fledged from the nest. Throughout the day on both Tuesday and Wednesday, the eaglet was in and out a lot, occasionally returning to the nest where Waiwash was waiting. During this time we also saw an eagle parent (probably the mother) feeding them both.

We congratulate Nause on this momentous occasion! Many eaglets do not survive their first flight for various reasons, so we were very happy to see the eaglet return successfully after the outing on Monday. Nause is now a fledgling, and we believe that very soon Waiwash will be one, too.

Cam watchers have asked what Nause might be doing while out of the nest for long periods. Although the eaglets instinctively know how to fly and even fish, these are skills that must be developed and fine tuned. Many eaglets die their first winter because they are not proficient at hunting and fishing for themselves. So between now and the coming winter, the eaglets will spend much of their time learning to scavenge dead food, learning to capture live food, learning to read and master the wind, learning to land safely, and learning how to interact with other creatures in their world.

flap23.jpgSo even though Nause is flying, the eaglet is still very dependent on the parents for food, and will continue getting meals from them for possibly another six weeks -- both on and off the nest.

Another cam watcher asked if the eaglets that went to Vermont can learn to fly and fish without parents around to show them. Last year, Craig Koppie -- our raptor biologist -- said that yes, the eaglets can learn all these things even without the parents. While our eaglets here will likely spend time watching the parents -- and also their sibling -- and observing how they fly and fish, it is not absolutely necessary to have an adult around for the eaglet to learn and master these necessary skills. The birds' built-in instincts will help them on their way. As for food, the folks in Vermont will leave food out for the fledgling eaglets until they can provide for themselves.

So as our eaglets begin exploring their world, where exactly are they going? Blackwater National Wildlife Refuge is a very beautiful and bountiful place for a young eagle to explore. At this time of year, there are many other eagles and ospreys about, so the young birds will get their first taste of interacting with other raptors.

The Blackwater River is the main body of water within the Refuge, and the eaglets will spend a good deal of time perching near it and fishing in it over the upcoming months. What makes Blackwater Refuge a popular place for eagles (and ospreys) is that the local waters are very shallow, and since both eagles and ospreys get their fish near the surface, the waters offer a habitat that suits their fishing styles. Also the Refuge has plenty of safe nesting areas and a healthy food population. Below are four photos that give you an idea as to where our eagles like to hang out. Click on the thumbnails.

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In the first shot, two adult eagles are perched over the Blackwater River and its marshes; the nearest tree is one that the eagles frequently choose for perching when near the Wildlife Drive. In the second photo, an adult eagle is perched on an empty osprey water platform. In the third shot, a perched eagle in the distance overlooks a fall scene where migrating geese fill the marshes. And in the final shot, the sun sets over a group of trees where immature bald eagles like to hang out together and watch for an easy meal in the river below.

Many of the adult eagles at Blackwater Refuge do not migrate because when winter comes and the fish are hard to find, the eagles can turn to eating small mammals and waterfowl. But many of the immature eagles will eventually leave the area once they become independent, as young eagles like to roam for several years before they reach breeding age. Once they are ready to start their own families, they will likely return to this area and begin looking for a nesting tree and a mate.

Until next time,
Lisa - webmaster
(contact)

Posted by Webmaster at 09:08 AM

May 14, 2006

Vermont Eaglets

chicks78.jpgNest Update: For a couple weeks now, we've been trying to find out what is causing the interference you see on the Eagle Cam (the blurriness and white bands on the image). We have swapped out all our equipment, moved the transmitter, removed overhanging brush, checked the computers, rechecked the camera, and still the problem exists. Interference with the wireless signal can be very hard to diagnose, but we plan to keep trying, and we thank you for your patience as we try to eliminate it.

This afternoon, we had several episodes where it looked like one of the eaglets was branching -- or sitting out of the nest and in the branches of the tree. This would be a lead-up to flying. We'll keep watching to see if we can see definite flight in the upcoming week. Also, we'll update the Gallery early this week.

On a different topic: A cam watcher alerted me to the fact that the Washington Post has put up a video of Martha (the injured eagle from Maryland), showing her capture and release. I don't know how long the video will be up, but here is the link.


Vermont Eaglets

Those folks who watched our Eagle Cam in 2005 remember that last year we had a three-eaglet nest, and because of our bountiful nest, we were treated to a special adventure. Craig Koppie -- an endangered species specialist from the U.S. Fish and Wildlife Service -- came to the nest and removed our middle eaglet (a female). Craig removed several eaglets from other nests at Blackwater as well, and took them all to Vermont, where they took part in the Vermont Bald Eagle Restoration Initiative -- a three-year project that hopes to reestablish nesting bald eagles in the only U.S. state without them.

vt2005.jpgLast year we were fortunate enough to be able to watch Craig on the camera as he entered the nest to retrieve the chick. (You can see the Gallery shots here.) Once the eaglets were in Vermont, we were able to watch them on the Vermont Eagle Cam as the birds sat in the hacking tower until they were ready to fledge. (A hacking tower is where transplanted birds wait until they can fledge). We then saw the eaglets become independent, and they eventually dispersed to various parts of the Northeast.

Several cam watchers have asked if we know what happened to our Eagle Cam female. We do not know at this time as no one has reported seeing a bird with her band numbers. We do know that two of last year's eaglets were found dead at a later time. This is not uncommon as many eaglets do not make it past their first birthday. One Vermont fledgling was hit by a train in New York while scavenging for food, and the other was found in a nearby field where it apparently died of a severe bacterial infection in its trachea. We were recently told that neither fledgling came from Blackwater.

This year is the last year of the Vermont Bald Eagle Restoration Initiative project, so last week Craig Koppie once again came to Blackwater Refuge to visit some of our eagle nests, looking for eaglet recruits. Melanie Lynch, of Chesapeake Bay magazine, is a good friend of ours and was kind enough to share some photos she took while covering the event for her magazine. These photos show Craig visiting a nest at Blackwater Refuge and then a nest on private property. All the nests Craig visited had eaglets that were not yet fledglings. Click on the thumbnails, and note that I left some of the photos large so you can see the details.

In the first shot, we see Craig with all his tree-climbing gear and his pick-up truck filled with crates for holding the eaglets. Craig is a master falconer, long-time raptor biologist, and licensed bird bander. In the next shot, Craig starts his way up a loblolly pine tree (about 60% of the eagle nests in the Chesapeake Bay area are in loblolly pines). In the third shot, Craig is under the nest (eagle nests can be around 60-100 feet off the ground), and in the fourth shot, we see Craig climbing over the edge so he can get access to the eaglets. At this point, the mother eagle is flying nearby and calling out but not bothering Craig.

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In the next set, the first shot shows Craig holding up his new best friend, which he's wrapped in a towel so the eaglet doesn't hurt itself. Normally Craig talks to the eaglets a bit to calm them when he first enters their nest, but once he starts handling them, the birds are normally docile. In the second shot, the bird is lowered down inside a gym bag to the U.S. Fish and Wildlife Service assistants on the ground (a couple of the USFWS people are from the New England office which oversees the Vermont project). In the third shot we see the two siblings on the ground, getting their first real look at these strange human creatures. And in the fourth shot we see the eaglets getting banded. Each eaglet gets a color band (so the eaglet can be identified with binoculars) and also a standard silver USFWS band with a unique ID number and the phone number of the Bird Banding Laboratory in Laurel, Maryland (where North American banding records are kept).

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In this final set of photos, the first shot shows Craig working his way up the next tree, which is on private property near the shore. Next we see one eaglet getting banded, and then in the third shot we see the two bands up close. Craig says the bands do not get hot in the sun, and are not uncomfortable for the eaglets to wear. Next we see a close-up of the handsome chick, and in the following shot the chick shows off his transparent third eyelid -- or nictitating membrane -- which he frequently uses to moisten and clean his eyes. And finally we have a parting shot of our beautiful eaglet.

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If you'd like to read more about the day's events, the Vermont Bald Eagle Restoration Initiative website recently posted an eaglet diary. Also the event was covered by a local news outlet here in Maryland.

And remember that you can now see these same eaglets in the hacking tower on the Vermont Eagle Cam. When the eaglets are ready, the bars will be lowered and the eaglets will be allowed to fledge with the hope that they will one day return to Vermont to breed.

Final side note: Just recently it was discovered that a breeding pair of eagles have produced a chick in Vermont. You can read the story here. This is promising news for the folks who have been working hard to reestablish bald eagles there.

And if you'd like to see a tree climber in action, the Colorado Division of Wildlife recently banded their eaglets as well, and there is an online video showing the climber at work.

Until next time,
Lisa - webmaster
(contact)


Posted by Webmaster at 06:02 PM

May 10, 2006

Endangered Species Day

flap20.jpgNest Update: Our two eaglets are 11 weeks old this week. We're still waiting for the first flight, but each day the eaglets seem to spend more time near the edge, sometimes with their wings spread. If we see a missing eaglet, we'll make the announcement on the cam page.

On another eagle topic, I wanted to give an update on Martha -- the female bald eagle that was injured at her nest near the Woodrow Wilson Bridge in Maryland. Fortunately, she was released in Delaware on Saturday. You can see a photo of Martha and read about her release on the TriState Bird Rescue website. Much thanks to TriState for their great work in saving Martha from her serious injuries.

And I also wanted to post the latest photos from Jerry McKenna, our eagle photographer friend from Illinois, who is watching a one-chick eagle nest in his home state. The first photo shows the rapidly growing eaglet admiring the flying skills of the adult. The second photo shows the remains of a turtle appetizer that the family enjoyed. The third photo shows how big the eaglet has become. And the fourth photo shows the cute eaglet being bothered by a pesky bee. Much thanks to Jerry for his amazing photography.

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May 11, 2006 --
Endangered Species Day:

The U.S. Senate recently designated May 11, 2006, “Endangered Species Day." This is America’s first national celebration of its commitment to protecting endangered species.

The reason this event was needed is because certain politicians in Congress are attempting to severely weaken the Endangered Species Act (ESA) and eliminate provisions that protect critical wildlife habitat. So Senators created this day to raise awareness about the success of the ESA and the need to protect species in our rapidly developing world.

For three decades, the Endangered Species Act has kept 99% of listed species from going extinct, but of all the species saved by the ESA, perhaps none is as famous or as beloved as the American bald eagle. In fact, the bald eagle has recovered so well that the U.S. Fish and Wildlife Service (USFWS) is now proposing that the bald eagle no longer be protected by the ESA, and they are taking public comments on this proposal until May 17, 2006. So I wanted to talk a little about what delisting means for our precious bald eagles.


How the Eagles Got into Trouble:

Bald eagles started to decline in the late 1800s mainly due to shooting, prey destruction, and habitat destruction. Then in the late 1940s, the pesticide DDT was sprayed extensively along coastal and other wetland areas to control mosquitoes. Unfortunately, DDT contaminated the fish that the eagles ate, and soon the pesticide accumulated in the eagles' fatty tissues and began to inhibit calcium production. This in turn led to thin eggshells that broke when the eagle parents sat on them. In 1972, DDT was banned from use in the U.S., but by then eagle populations were in serious trouble. So in 1978, the U.S. Fish and Wildlife Service listed the bald eagle as "endangered" (under the Endangered Species Act) in 43 of the contiguous states, and "threatened" in Michigan, Minnesota, Wisconsin, Oregon, and Washington. (The bald eagle has never been endangered or threatened in Alaska and has never lived in Hawaii.)


How the Eagles Recovered:

pgceagle.jpgThe habitat protection provided by the Endangered Species Act, combined with the banning of DDT, helped bald eagles on the road to recovery. Unfortunately, DDT's dissipation from the food chain was very slow, so the recovery was not immediate, but over time -- with the help of the USFWS, environmental groups, local governments, corporations, universities, tribes, and concerned individuals -- the eagles made enough of a recovery that in 1995, the bald eagle was reclassified as "threatened" in the remaining 43 states where it had been "endangered."

Today, the USFWS reports that the bald eagle population in the lower 48 states has increased from 417 nesting pairs in 1963 to an estimated 7,066 nesting pairs in 2005. The USFWS is now declaring the bald eagle "recovered."


A Delisted Bald Eagle:

So now the big question is: Can the bald eagle prosper without the ESA's protection? The strength of the ESA -- and what makes it different from other wildlife laws -- is that it protects critical habitat for endangered and threatened wildlife, because without a safe home, a species cannot survive.

Bald eagles are generally known to be very sensitive to human disturbance, and sometimes will abandon nests and eggs if spooked by humans. The ESA helped the eagle by protecting it from disturbance on shoreline and waterfront habitats where eagles need to live, but where humans like to play, develop, and log.

If the eagle is delisted, protection of the bald eagle will fall to two laws that are currently on the books: The Bald and Golden Eagle Protection Act (BGEPA) and the Migratory Bird Treaty Act (MBTA). Both acts protect bald eagles by prohibiting killing, selling or otherwise harming eagles, their nests, and eggs.

However, a controversy has arisen because some experts and environmental groups do not believe that these two laws will be enough to protect eagle habitat because habitat protection is not the goal of either law. In response to this concern, the U.S. Fish and Wildlife Service has now published voluntary National Bald Eagle Management Guidelines, which are intended to provide information to people who engage in recreation or land use activities that might impact eagles.

In addition, the USFWS is also proposing a regulation to clarify the term "disturb" as it relates to eagles under the BGEPA. Now "disturb" will be defined as actions that disrupt the breeding, feeding, or sheltering practices of an eagle, causing injury, death or nest abandonment. Although the USFWS has accepted this definition of "disturb" for some time, now the Service will officially codify it.

If delisting occurs, the USFWS will continue to work with state wildlife agencies to monitor the status of the bald eagle for a minimum of five years after its delisting, as is required by the Endangered Species Act. However, this monitoring can become more difficult in tight fiscal times like we have now.

The USFWS has stated that if monitoring shows that the bald eagle is faltering in its recovery, they can begin the process of putting it back on the endangered and threatened species list, but that could take time.

wdeagleStates that list the bald eagle as endangered or threatened within their own boundaries can continue to do so after the delisting; however, experts predict that once the bald eagle is delisted at the federal level, many state governments will follow suit at the local level and remove it from their own lists.

On the positive side, eagle behavior has been slowly changing as the raptors spend more time near humans. Now we are seeing more eagles that are willing to nest near humans and even in human-made structures. But not all eagles are this comfortable around people, and birds in more pristine areas are likely to remain highly sensitive to encroachment.


What You Can Do:

Until May 17, 2006, the USFWS is taking public comments on three items: The delisting of the bald eagle, the proposed National Bald Eagle Management Guidelines, and the proposed definition of the term "disturb." The Service wants and needs the input of all American citizens who have an opinion or who have information about bald eagles that will help the Service make the right choices in their actions.

On the USFWS Eagle Delisting web page you can find more information about the delisting proposal, the management guidelines, and the "disturb" action. You can also find out how to send your comments via email.

The fact that we have reached a point where the bald eagle can even be considered for delisting is a true testament to the effectiveness of the Endangered Species Act and its ability to protect precious wildlife and their habitat. But we must be sure that we are removing the bald eagle for the right reasons, and we must be sure we will have a system in place to continue protecting the birds even after they are out of the jurisdiction of the Endangered Species Act.

America's national symbol deserves no less.

Until next time,
Lisa - webmaster
(contact)

Posted by Webmaster at 06:12 PM

May 04, 2006

Flight Mechanics

flapNest Update: Our eaglets are ten weeks old now, and we're currently waiting for their first flight. Nause, our oldest eaglet, will likely make the plunge first. Once the eaglet fledges, it will be gone from the nest for a little while, so we're looking for a sustained period where only one eaglet is visible, or we're looking for a clear shot of the eaglet leaving or returning to the nest. Once the eaglets fledge, they will continue to use the nest as home base for four or five weeks until they become independent.

Speaking of Blackwater Refuge eaglets, one of our cam watchers -- Woody Dawson -- sent me a photo he just took from our Wildlife Drive showing a nest that has three bald eaglets in it. In this great close-up, you can see two of the eaglets and the mother. The third eaglet was farther back in the nest.


Flight Mechanics

Now that flight is imminent for our eaglets, it's a good time to talk about how eagles fly.

A full-grown eagle has over 7000 feathers on its body and has a wingspan of 6-7 feet (upwards of 8 feet on the larger female). The eagle's large wingspan means it must use a great deal of energy to flap its wings. Consequently, bald eagles don't do that much flapping, but instead spend a great deal of their time soaring, which requires about a 20th the power needed for flapping.

Eagles soar or glide when they migrate, and also when they hunt and fish. Using thermals and updrafts, an eagle can soar continuously for hours while using little energy.

Eagles can fly to an altitude of about 10,000 feet, and during normal level flight, reach a speed of 30-35 mph.

Like all birds, eagles have very light bones; in fact most of their bones are hollow and contain only air. If you added up the total weight of their bones, it would be about half the total weight of their feathers.

flapEagles have several types of feathers to aid them in flight, including the primary and secondary wing feathers, tail feathers, and coverts.

The ten outer primary feathers are on the end of the wing; these feathers are stiff and narrow because they meet the air first and must provide wind resistance. These outer primaries are also notched and they can open like fingers, which can help a flying eagle to achieve lift and drag.

The inner primaries and secondary feathers are flatter and will overlap to provide a smooth lifting surface.

Body, plume and downy feathers are needed for body covering, streamlining, waterproofing, and temperature regulation. This graphic shows you individual samples of several different types of feathers for both the adult and immature bald eagle.

When an eagle wants to move fast, it can turn the front edge of its wings into the wind and cut through the air. If it wants to slow down or stop, it can spread its wings and drag them through the air to create a "braking" effect.

When eagles flap their wings, the power comes from the downstroke. If you remember, we mentioned in a previous log that when the eaglets are flapping around the nest and their feet get off the nest floor, the lift is created by a strong downstroke.

Woody Dawson was kind enough to loan me some of his fantastic bald eagle photos that he took in Alaska. In this series of shots, you can see how the eagle uses the downstroke to get its feet off the ground and its body into the air.

If you'd like to read more about eagle flight and eagle feathers, here are two informative articles: "Wings and Feathers" and "Bald Eagle's Quest for Flight."

Until next time,
Lisa - webmaster
(contact)

Posted by Webmaster at 07:54 PM