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Frequently
Asked Questions Special thanks to Eagle-Eye Nye for providing his time and expertise in responding to your questions! From:
MINNESOTA From:
WASHINGTON
Bellingham,
WAQ: Do eagles see in black or white...or in color and if in color do they not like the color red? A: I knew I had seen a very thorough treatment of eyes and sight somewhere, so below is what I found at this web-site:
From:
VERMONT
Ferrisburgh
Central SchoolQ: There was a sighting of eagles in Vermont that had about 10 eagles in the same place. A friend sent pictures to us of the birds. Our question is - Would it be typical to see this many eagles together in a group? We thought they travelled alone and didn't expect to hear that they were in a flock. Julie and Jenny Grade 5-6 Ferrisburgh Central School A: Hi girls; The answer kind of depends upon the time of year! It would be very unusual to see such a number together during the breeding season, since eagles are territorial and typically space themselves out as breeders, so you would only see a couple of adults and their young "together". I have to say though, that in some places where eagles are extremely abundant, such as in Southeast Alaska, one could see such a grouping of immatures and non-breeders in an area where no nests are (and thus are "safe" from territorial interactions). However, I can assure you, this is not the case in Vermont! Sorry to have to say that ! I assume the sighting you mention was between December and March, and likely along a major River or lake, and these were wintering birds attracted by some food source. During winter, eagles are gregarious (will be in groups and tolerate each other) by necessity, to share common food sources. In summer, suitable habitat is less limited and thus they can afford to be more solitary and territorial. No nesting eagles that we know of yet in VT, although keep the faith; one will be there soon! Q: Do the eagles migrate in flocks? What is the typical size of a group of eagles? Jenny and Julie Grade 5-6 Ferrisburgh Central School A: No, eagles migrate alone as far as we know. Some breeding pairs may migrate together, but we do not know this at this point; this is a question I would like to answer using our satellite-telemetry project you study through JN. How do you think we could determine this? This is not to say that on a given day in the fall or spring, many eagles might not be seen moving south or north during the same day (for example some hawk-watches may report 50 or more eagles moving by in one day). This does happen, but it is related to the weather conditions (suitable days for migrating), which facilitate many birds moving, but not necessarily as "groups" as we see in waterfowl like geese. Q: We want to know if eagles ever stay in an area for the whole year? We are hoping that eagle #E47 stays in Ferrisburgh! Jenny, Julie, Shane, Avery, Justin and Kate Grade 5-6 A: Wow, Ferrisburgh, you guys are really into this! All-right! Yes, eagles do sometimes "stay" in an area all year round. I'm sure you can figure this out with a little thought. Why would they stay or move? Knowing that, where might you expect eagles would not "move" ? A: If they can fulfill their life-functions/needs, why move? For eagles, this means open water and food; if they can find enough all year-round, why leave. In such places, like Southeast Alaska and other coastal areas like Maine, Chesapeake Bay, etc., eagles often do not need to move and don't ! Even in some places along our Hudson River here in NY, if we have a mild winter and the River doesn't freeze up solid and the eagles can find what they need, they will stay by their territory year-round. This seems like a pretty smart strategy to me; rather than being a determinant migrant (they go regardless of the weather and food, like ospreys do), eagles appear to be opportunistic migrants, and adapt their movements as needed. For example in your area, the winter was very mild this year and most of Lake Champlain was open all winter long, attracting and keeping wintering eagles there. If you study the JN maps, you'll see a couple of our birds "short-circuited" (didn't go all the way south to where they were previously caught) and spent a lot of time up on Lake Champlain. Concerning E47, again, you can answer that one ! We caught her a year ago February; where did she go in spring? What do you think she'll do this year? From:
KENTUCKY
Hudgell Home School Q: I go to Land Between the Lakes in Kentucky each winter to see the eagles. Do the eagles that winter in Kentucky go as far north as the eagles that winter in New York? A: Excellent question. I am aware that good numbers of eagles can be seen at LBL each winter, but have never given much thought to where they hail from. Let's do some "on the spot" thinking about this. We (in New York) have captured and banded well over 100 wintering bald eagles over the past 20 years. Most of these have turned out to be birds that indeed do winter in New York, but we have also captured some that were obviously in transit between places (note eagle E63 that we caught last year, but which we found out this year wintered in Maryland at the northern end of the Chesapeake Bay). However, E63 is by far the exception, and represents the furthest south any of our winter-captured eagles have been recorded. As you also know from studying the JN data over the years, our wintering eagles come from and thus represent a large geographic area of eastern Canada. It would seem logical then, that if some of these eastern Canadian birds migrated that far south, we would have snagged one by now and seen this. Therefore, I would conclude that, no, the LBL birds do not hail from the same northern territories. Likewise, from banding and radio-tagging studies conducted over the past two decades in other states such as in TN, MD, VA, FL and other mid-east and southern states, we do know that birds from these areas use the LBL. Although I don't believe any radio-tracking studies of these LBL birds has been done, my best guess is that birds that winter there come mostly from nearby breeding areas and from the greater Cheasapeake Bay population. A great contact for information on these eagles is Mr. Bob Hatcher of the Tennessee Wildlife Division, who is very familiar with those birds and that area; I'm sure he can give you lots more information on this. I'm sorry I do not have his address or e-mail handy, but I did search out and find a web-site for LBL you may want to check out: Q: Do the same eagles winter in the same place each year? Or would Kentucky' eagles some winters migrate to New York? A: I think I've anwered the second part of your question above about the LBL. Our years of studying wintering eagles have shown us that, indeed, there a high "site-fidelity" by the birds, especially older birds. Young eagles may wander around a bit more during their immature years, before they too settle on an area to their liking which becomes their habitual winter home. From:
NEW YORK
Highview
Elementary SchoolNanuet, NY Q: Do the bald eagles have a special technique for breathing when they fly so high? A: Good question! This sent me to the bird physiology books myself! In reality, eagles tend to use very little energy "when they fly so high". Even though they can reach altitudes of over 10,000 feet, they are usually soaring to these heights, and taking long glides to cover ground, then soaring up again and repeating the process. By flying in this way, there body is really not demanding much oxygen, not any where near as much as when they are much closer to the ground and expending considerable energy flapping their wings. So, no, they have no special adaptations for breathing at high altitudes. Q: Since bald eagles spend time in warm and cold climates, do they like it better in the heat or the cold? A: That's a hard one, because you are asking me to predict what an eagle "likes". You are right that they are found from the hot, hot deserts of Arizona to the very cold climes of northern Canada and Alaska. I don't think it is so much of a question of what they "like" or don't like, but rather which condition is harder (more stressful) on them, This , also , is tough to say, since they do succeed (reproduce successfully), under a wide variety of such conditions. My own feeling, based for one thing upon raw numbers in very "hot" spots versus colder spots, is that the extreme heat is deadlier for them. You (they) can't shed excess heat easily, and even here in NY we have had nestlings expire due to hyperthermia, but they can maintain body temperature given enough fuel (food). Once in a while prolonged periods of wet weather or snow can be a factor on nestlings also. You'll find the vast majority of bald eagles living out their lives in temperate to colder climates. Q: Has there ever been a tagged eagle that has been shot down by a hunter? A: Does the sun come up every day ?? Of course, unfortunately. We have found many of the eagles we have banded and released dead due to gunshot, and last time I checked, that was one of the major causes of mortality we see (others include vehicular collisions and other trauma). We need to be careful of the use of that term "hunter" though. Although, technically, anyone pursuing a creature to kill or capture it is "hunting", the hunters we generally think of today are sportsman who are very concerned about all natural resources and are some of the first to insist on their protection. I can't print the word I would use for people who shoot eagles and hawks, but they are definitely not the hunters I associate with the sport of hunting. Fortunately, we have come a long way in educating people about this and far fewer eagles are shot these days than 10-15 years ago. This is not a population-limiting factor, as much as it does anger me. From:
MISSOURI
Sappington School, LEAP program St. Louis Q: If the temperature gets very hot, warmer than normal for this time of year, will that affect the Bald Eagle migration? Will the eagles migrate faster or travel further than usual? A: As I've indicated in some of my responses above, mild (warmer) weather, which translates to more extensive open water and hence more food, does affect the movement and wintering locations of some eagles. Despite this, I suspect some eagles, especially older adult birds used to going to the same, successful wintering area, still will go to their traditional site even during mild winters. We have also seen the very mild late - winter periods, such as this winter, cause birds to "move out early". I would say overall, they stay pretty much with movement based on day-length, thus calender time, but milder weather sure does allow them to move around a lot more. I don't believe it would affect the speed of their migration. From:
IOWA From:
IOWA
Fredericksburg HS Q: After observing a bald eagle perched in a tree along a river for over 20 minutes, I observed it fly to a tree 10 yards away and break off a branch in its talons and fly off. Could it be possible that the twig could be used for building a nest? This occurred in Iowa in early February. Two eagles have been seen in this area throughout the winter. Thank you! A: Absolutely it could! I assume the eagle you observed was an adult. Immatures may occasionally do this for play or practice, but it is typical behavior for adults prior to and during nesting. What you saw could be a local breeder getting its nest "ready" for the breeding season (here in NY we have some pairs who begin decorating their nests in early February, and I'd bet Iowa would too), or, it could have been a wintering bird just fooling around and "feeling its oats" in anticipation for migration and nesting back up north. Very rarely, some wintering birds will actually build a nest on their wintering grounds during the winter season, even though they have no intention of staying and using it (they just might be very stimulated breeders!); we have seen this in NY, and the pair return to their "winter" nest and decorate it and sit in it each winter, before leaving for their "real" nest somewhere up north in late March. The fascinating thing to me about what you describe, and which I've also seen, is how the heck the eagle "knows" that the stick they fly at and hit in mid-flight will give way! It's got to be a good decision between flying force at the stick to break it off versus not sort of flying yourself into a brick wall so-to-speak! How do they know ahead of time the stick they've "chosen" will break off ?? (that's a rhetorical question, not a challenge one!). Anyway, that is a neat thing to observe! I would look for a nest in the vicinity! Peter
E. Nye
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