Tuesday, May 10, 2016

What is going on at the Decorah North Nest?

What is going on at Decorah North? The oldest eaglet, DN1, is displaying far more aggression than we are used to towards its siblings. It is upsetting to human watchers, especially since little DN3 takes much of DN1's biting, yanking, and twisting. However, we have also seen DN1 and even DN3 attack DN2. In most cases, the aggressive behavior ceases once the target submits, but we have seen biting and bonking continue past submission at least twice.

Why is this happening?
We don't know. Food certainly seems to be part of the puzzle, since we've often seen the eaglets act aggressively towards one another as they establish a feeding-related pecking order. However, we've also seen aggression break out in circumstances seemingly unrelated to food. For example, DN3 attacked DN2 at around 2pm this afternoon, giving it multiple bites, yanks and twists before DN2 submitted. The eaglets had all been fed well earlier today, so why the aggression? Perhaps differences in age and size also contribute to aggression. I would tend to believe that aggressive behavior is hard to stop once it starts, and I'm very curious whether we will see the drop-off in aggression here that we have seen in Decorah.

While siblicide is rare, aggressive behavior is common. It ranges from the relatively mild aggression seen in Decorah and at Fort St. Vrain to the biting, twisting, and yanking seen at Decorah North, Southwest Florida, and several other nests. I think this looks odd and frightening at least in part because Decorah has tended to lack extreme aggression. But Decorah and Fort St. Vrain could very well be outliers when it comes to eagle behavior. At this point, only the eagles know for sure.

Is DN3 growing normally?
It is very tough to tell with nothing but the two 'Cropzillas' to compare it to. DN3 is growing in thermal down to replace natal down, has gotten larger relative to the other two (seemingly overnight!), and is growing footpads. What we've been able to see of its beak has indicated a fairly regular size and shape in accordance with eaglet growth curves, and its talons are appropriately changing to black.

DN3 is just moving into the steepest part of its growth curve. The next five to seven days will give us a look at whether or not it is growing normally. We'll also look for developmental changes like nest wandering, attempting to stand, and tracking Mom and Dad outside the nest. DN3 has already been observed doing some of those things on warm days and we should see them more often as its thermal down grows in.

Is DN2 growing normally?
Yes, DN2 is growing and behaving normally.

Will DN3 survive?
DN3 is strong, gets fed, participates in nest aggression, and submits appropriately. The eaglets tend to fight with their beaks instead of their talons and, while the aggression looks frightening, DN3 hasn't been badly injured. It is rapidly growing in thermal down, which will help protect it from cold weather and aid nest exploration. Fighting is very hard to watch, but generally rare when one compares the time spent fighting with the time spent laying around the nest and eating.

There are no guarantees, but siblicide is uncommon and DN3 is much stronger than it seems. It often comes back with its own beaking, displaying its own fierceness, or can be seen afterward cuddling up to a former aggressor. We are hopeful it will survive and even thrive as it grows...but again, there are no guarantees with wildlife.

Will you intervene?
Absolutely not. We might consider interfering if the situation were human-caused, but these behaviors are completely normal from an eagle perspective. If we rescued every eaglet we were concerned about, there would be no wild eaglets left to watch. It is very important to keep eaglet behavior in perspective. For the most part, the parents have acted according to our expectations: feeding, interacting, brooding, and in general caring for their family. While the eaglets fight with one another, they spend more time cuddling, eating, and sleeping. While the fighting is upsetting to watchers, none of it is out of line or outside the parameters of normal eagle behavior.

In summary, the worst may happen but we are not giving up on DN3. The next five to seven days will tell us a lot more about its growth. It looks like we are starting to get pinfeathers on DN1, which means its growth will start slowing as feathers take over. While we have never seen this level of aggressive interaction in Decorah, eagles have survived it at other nests. We remain hopeful.

Kay from SOAR also provided some feedback after she was approached about the situation. She agrees that the situation "looks" terrible but that at this developmental stage of the eaglets they don't have a huge amount of strength in their beak.  Right now, those beaks are something like pointy salad tongs. Hopefully all three eaglets will grow well and this will not be a concern for much longer.  







24 comments:

Judy Shepps Battle said...

"Pointy salad tongs" indeed. Now if that doesn't put some of the drama in perspective, nothing will!

I guess the aggression level of 1 doesn't bother me as much as if I hadn't seen it before on the SW Florida nest. But in both SWFL and DNN the parents never fed the babies to the point of overstuffed crop (and resultant food coma) as the Decorah parents tend to do.

I had wondered why SWFL just didn't feed the dominant one into unconsciousness and then take care of the younger one (also 3 days younger) until it has happened in DNN and I realized that neither of these nests has a ready food supply. Hunting is uneven. Decorah nest, within spitting distance of the fish hatchery, will never lack for ready food.

Perhaps when food supply is uneven, there is more aggression. Who knows. Surely not I.

I am comforted by the fact that the aggressive behavior is situational and that most of the Trio is in a cuddle pile with 3 in the middle being kept warm and (on rainy days) dry.

I totally hope 3 makes it and suspect he will. He was standing today and holding his wings out. But, the reality is that if he can't survive on the nest, he doesn't have the skills to survive outside the nest (again, in my opinion).

But we are visitors and observers of the eagle world. And we sure are seeing that world in action.

Thank you RRP for making this education possible!

eaglesrock29 said...

Excellent blog as usual, Amy. Thank you so much! We are all rooting for DNN3 and also for DNN1 and DNN2. As you noted, SWFL experienced serious sibling aggression this year (and prior years), but E8 rose to the challenge. I will keep my talons crossed that DNN3 is as strong as he appears to be. DNN3 may be light in weight, but he is no light-weight. Seems to be feisty and strong -- blessings to you, DNN3. <3

David Tignor said...

Thank you for that explanation of what's going on. Can you tell us when we will have our chat back, please? Thank you!

Darrel & Linda Ferguson said...

Isn't tha why we are watching the second nest to learn about all the differences. As for siblings if the four kids that grew up in our home didn't kill each other my guess is the three will be fine, just different from what we were used of at N2B. Okay, I'm back to sewing! Enjoy ur eaglets they will fly the nests all too soon!❤️

Melody Baird said...

We would love an update on the nest! For those of us who can't watch constantly we use the chat to catch up and check in on the eaglets, especially the little one. Now that the chat has been closed temorarily by explore.org. we have no way of knowing what's been going on. Thanks.

ferniefootloose said...

Thank you RRP. This site is education at it's finest. I'm sorry that there has been a need to shut down temporarily, and wish everyone would settle down....

miss h. said...

Thank you so much for the updates!

moeagle said...

Thank you Amy for addressing all of these issues, I also appreciate Kay's insight.

I'd like to say that I agree with everything that Judy Shepps Battle said in her comments above, especially regarding the feeding differences between Decorah and DNN. For the first few weeks Mom and Dad Decorah offer a constant supply of food to their eaglets with frequent feedings throughout the day--not as consistent on this nest. One other difference that I have noticed is that the DNN parents stay off the nest more than the Decorah parents--and much earlier. It appears to me that DN3 has been left uncovered for long periods of time before he/she was old enough to thermoregulate. It sometimes seems like even now Mom and Dad Decorah spend more time on the nest, and the Decorah eaglets are almost fully grown. But these are just my observations, for what they're worth, I'm certainly not an expert. It sure has been interesting to see the differences between these two nests.

Thank you RRP for allowing us into this wonderful world of eagles, I learn something new every day.

playmytune said...

I'm sorry chat has been closed. I'm new to nest watching and Decorah North has been the nest I visit most often. I have learned so much within the last few months of watching the different nests but have learned the most at Decorah North. When I ask questions I get a reply immediately.

Thank you Raptor Resource and explore for allowing me to visit this site. You're doing a wonderful job. And it is true that you still teach an old dog new tricks.

Betty Norman said...

It's understandable that chat has been closed. I found it difficult to go through the large volume of comments to find useful information such as (1) number of recent feedings, (2) behavior of parents, (3) eaglet activity, and (4) condition of DNN3... and DNN2 for that matter. However, I do miss this daily commentary. Would it be possible to allow comments from trusted posters, such as GAbear, who is a moderator? GAbear has been posting useful commentary on this site long before eggs were laid, and it would be great to see those comments again. Many thanks to RRP and Explore.org for making the viewing of Decorah North nest possible. It is one of the more interesting bald eagle studies available to viewers, not to mention the excellent cameras and camera operators!

L. Zuckerman said...

I don"t think it's understandable at all. Why should thousands of followers be punished because of a few? Most of us can't watch the cam all the time and depend on the comments to keep us up to date about what happened while we were away. Right now, I no idea if there has been a feeding today, how those precious eaglets are doing, if there have been any issues, nothing. How can you teach the public about these gorgeous birds if all comments have to be candy coated and cannot voice any concern or fear for the eaglets? This has been a great cam experience but you can't control peoples emotions any more than you can control those eagles.
This is a very disappointing development. I expected more from Explore.org and the Raptor Project.

Lindsey Zuckerman

kdavisrunt said...

Thank you RRP for all the great information!!

Sharon Marz said...

Thank you for the update on the Decorah North nest and DNN3. I watched them feeding this morning and did not see DNN3 get any food. This is my first year watching an Eagle cam and I have been focused on watching the Eagle's nest at the fish hatchery in Beulah Michigan. From what I have seen the food does not seem to be plentiful at the DNN. Yesterday one of the parents was trying to get meat off of the dead turkey that has been in there for several days. It is extremely hard to watch DNN3 struggle to survive and also hard to realize that there is nothing that we can do.

Pat L said...

Nice job by the monitors this afternoon with the camera. Great wide angle shot, you can see the eaglets in the nest, mom/dad standing guard and the cows in the pasture.

dennyk58 said...

Thank you to the monitors for zooming out quickly when Lil peep was being picked on. This nest is becoming very hard to watch as an adult, let alone for children. With that being said, I know there is no intervention unless it is brought on by humans. I am certainly not an expert, but I have observed the parents bringing placenta to the eaglets many times. While we do not know what animal the placenta came from, one can assume it is from the farm below. So the question that I must ask is: if the placenta contained environmental contaminants as antibiotics, steroids, etc., that can certainly have played a part for eaglet 1 to be super aggressive (more than has been observed at other nests) and why eaglet 3 is malnourished and why the parents are not feeding. This is important as this nest could, very well, have been affected by humans, certainly not meaning to do the same. We do know that in some cases raptures are dying across the United States for no apparent reason. Of course, weather conditions, etc., may have been the cause. However, human intervention should happen to determine exactly what is happening at this nest. Thank you.

miava said...

Not an expert but I have watched quite a few nest. And D1 is a nasty piece of work! He is not cuddling D3 he is purposely sitting and stepping on him to hold him down. The parents especially the mom doesn't even care. If this is nature why don't the other nest behave like this?

erbrya said...

this is a great camera! i have become addicted to both of the decorah nests this year. Eagles are more like dinosaurs than mammals, so people need to look through a less cuddly lens. 2 out of 3 eggs to adults is a successful brood in any bird clutch.

yankeexpress said...

The hour-by-hour DNN nest information being asked for is available all day at the RRP forum in the DNN thread:
http://www.raptorresource.org/forum/index.php?topic=2155.msg480624#msg480624

miava said...

No one said the camera wasn't great you can see everything that's going on. I only mentioned cuddling because others think that's what D1 is doing to D3. Look a little closer. D1 is purposely immobilizing D3 and when he's finished killing him D2 better watch out because he's next. There is more going on in this nest than D1 wanting the other two know who's boss. D1 wants the nest and his mama all to himself. The mama hardly is ever in the nest and I don't blame her. If I had hatched a little psycho I wouldn't stay in the nest either. I'm just glad that all the nest aren't like this one. No hard feelings it's just how I see it. Hope I wrong.

miava said...

It looks like D3 nightmare is finally over. That's what happens when you're mama doesn't feed you and your sibling purposely smothers you! RIP D3. You can say what you want but all nests are not like this. D2 better watch his back!

dennyk58 said...

At first light I saw the same, poor lil peep...rest in peace brave bird...I agree, D2 is there with his/her head down as mom or dad is feeding D1...I can no longer watch this nest...nature or not, something should have been done so that little bird didn't have to suffer...best to all

miava said...

I agree but did you see how D1, D for Demeon, is starting in on D2. And when he did mom promptly left the nest. Unfortunately D2 it's next. Demeon might not be able to smother him but he can starve him and tourtière him physically. This is a nest from Hell!

raven sanchez said...

Not very good parents..extremely inexperienced..these other babies are hungry..can there not be an intervention now?

Karen Jensen Studniarz said...

from MDKaren Why were the comments closed on the cam? Did something happen between 1 and 2?