May 12 2014

Start Late, Finish Early

Published by at 7:20 am under Birds of Prey,Peregrines

Gulf Tower chicks eat dinner, 6 May 2014 (photo from the National Aviary falconcam at Gulf Tower)

With two Pittsburgh raptor nests on camera we're able to watch the nest cycle differences between peregrine falcons and bald eagles.  A big difference is timing: Peregrines nest later but they finish earlier.  We're about to see that unfold.

Back in March it felt like peregrine egg laying was "late" because the Hays bald eagles had been incubating for two and a half weeks before Dori laid her first egg at the Gulf Tower.  In fact Dori was early, even by her own standards.  We just didn't realize how much earlier bald eagles begin.

On May 6 (above) the peregrine nestlings were still developmentally behind the eaglets.  They weren't very mobile and were still covered in fluffy white down with no apparent flight or facial feathers. They looked like babies.

On that same day the eaglets had been mobile for two weeks, had already grown some head and body feathers and had started to grow flight feathers.  They already looked like eagles (below).  PixController's YouTube video of the bald eagles' growth in April shows how they got to this stage.

Pittsburgh Hays eaglets, 6 May 2014 (photo from the Pittsburgh Hays eaglecam by PixController)


Despite their late start the Gulf Tower peregrine chicks are about to surpass the Hays bald eagles.  The table below shows they'll depart their nest two+ weeks before the eaglets.  The peregrine fledglings will fly right away (departing a cliff nest requires flight) while the eaglets will likely flutter from their tree to lower vegetation or the ground where they may wait 1-3 weeks before flying again.

Keep in mind that fledge dates are just estimates.  Young birds learn to fly on their own schedule.


____________ 1st Egg Hatch 1st Flight/Nest Departure
Gulf Peregrines 3/10 4/20-4/23 5/28-6/02 (5.5 wks)
Hays Eagles 2/20 3/28-4/02 6/16-6/28 (11-12 wks)



Start late, finish early.  Peregrines are faster than eagles in everything they do.


(photos from the National Aviary falconcam at Gulf Tower and the Pittsburgh Hays eaglecam via PixController)


18 responses so far

18 Responses to “Start Late, Finish Early”

  1. kathyon 12 May 2014 at 11:19 am

    I am having so much fun watching these falcons thanks donna also love my scapbook supplies, kathy mary lous sister

  2. carol kyrimeson 12 May 2014 at 5:07 pm

    I started singing mcgarford park when her legs looked like “a striped pair of pants”. These two couples are both extrodinary parents. I’m into humans getting more instinct if it means this level of parenting.

  3. lillianon 13 May 2014 at 1:51 pm

    I keep watching at the Pitt Cathedral nest and feel so sad watching Dorothy and E2 fussing over that egg that won’t hatch. Dorothy just keeps standing on the rail and looking at the egg. Occasionally she will go stand over the egg and sometimes I have seen E2 come in and stand by the egg, too. It is like they are mourning the loss of their child! How long will they continue to stay by the nest?

  4. Kate St. Johnon 13 May 2014 at 2:34 pm

    lillian, Dorothy and E2 might not be mourning. Perhaps they’ve adjusted to Dorothy’s menopause-like phase of life. They are always at the nest from March until early June so it is normal for them to be there now. They will begin molting in early summer and probably stop visiting so much.

  5. John Thomsonon 14 May 2014 at 10:18 am

    Fascinating. Thanks Kate.
    You said the Bald Eagles first flight/flutter would be lower vegetation or the ground below nest and may wait 1 to 3 weeks before flying again. That is amazing that they could survive on the ground that long alone and have to depend on parents to bring them food?

  6. Kate St. Johnon 14 May 2014 at 10:26 am

    John Thomson, last year the eaglet landed in a tangle of grapevine where he/she stayed for about that amount of time. Considering how high they nest there are a lot of places to land.

  7. John Thomsonon 14 May 2014 at 3:37 pm

    Kate thanks for quick reply. Did/do all Eagle parents (Hays last year) instinctively keep going to where the fledglings are near/on the ground and feed them until they fly away? Where can I read about Hays Eaglets from last year? Someone on WildEarth Hays Bald Eagle chat just said today that they had heard that last years Hays Eaglet was picked up when it fluttered out of the nest and they kept it until it could fly off on it’s own? If that happened was it the National Aviary or PA Game Commission? Thanks.

  8. Kate St. Johnon 14 May 2014 at 3:41 pm

    John, last year’s eaglet was not picked up (I never heard of this happening at all). The eaglet stayed in the tangle of vines, well-protected and fed by its parents, until it was ready to leave that zone. Eaglets make sure their parents know where they are. Eagle parents keep track of their kids just as good human parents keep track of their toddlers. These are good parents. They will keep track of them and carry food to wherever these three are until they are “grow up” and fly *to* their parents to nag for food (like teenagers).

  9. John Thomsonon 15 May 2014 at 3:56 am

    Thanks Kate. I am impressed by the extraordinary abilities these creatures are designed with.
    I remembered that the chat on the Hays Eaglecam yesterday said that last year when the one surviving eaglet fledged/fell out of nest one of the parents swooped down and caught it? Are they capable of doing that?

  10. Kate St. Johnon 15 May 2014 at 6:09 am

    John Thomson, here are some clarifying remarks about the eagle chat that said: “last year when the one surviving eaglet fledged/fell out of nest one of the parents swooped down and caught it”

    “surviving” eaglet: Last year there was no camera so we have no idea how many eggs there were nor how many hatched. For all we know there may have been only one fertile egg and therefore one eaglet from the start. We surmised that there was a chick in the nest by watching (from the trail) as the parents bowed to feed something small in the nest. We learned there was one eaglet when her head was tall enough to appear above the nest rim. It is accurate to say, the “only” eaglet. “Surviving” is an assumption based on no data at all.

    “fledged/fell out of nest” For definition purposes I’d like to make a distinction between fledged & fell. Fledging, however clumsy, is a purposeful nest departure when the young bird already has enough flight feathers to leave. The parents know when the young have reached the right stage of development and actually urge the young birds to leave the nest. To do this bald eagle parents offer food at a distance from the nest, “Come fly out here and you’ll get this nice fish.”
    “Fell” is when the bird doesn’t have flight feathers yet and something (a wind storm, for instance) jolts the young bird out of the nest. Naked baby robins come to mind.
    In between fledged and fell are the incidents when a young bird is a few days away from fledging and is frightened into leaving too soon and can’t quite fly. This happens to small birds (robins) but very rarely to bald eagles because they’re top-line predators with powerful beaks and claws and rarely have reason to leave. Young eagles (and peregrines) have to be urged to leave because they have a pretty good deal while in the nest –> an all-you-can-eat buffet!

    As time-of-departure approaches bald eagles (and peregrines) watch their young closely to see if they’re about to leave. Experienced parents, like these bald eagle parents, know the signs. The parents watch. When the young bird flies for the first time the parents follow it and make sure it’s OK at its new perch. This is the same as any human parent would do while watching his toddler. Eagles do not “catch” their young because their beaks and talons are weapons that would wound their young. If you are watching from the ground at the moment the eaglet flies for the first time you will see the parent follow the fledging. Click here for a description of last year’s eaglet fledging moment (flying from the tangle of vines) with a link to Tom Moeller’s photo sequence of the flight.

    p.s. I don’t know about bald eagles but from years of watching peregrines I can tell you that the parents reward their “kids” when they fly for the first time. As soon as the young bird has landed they bring it some food.

  11. John Thomsonon 15 May 2014 at 3:55 pm

    Thank you so much Kate. You really did a lot explaining to answer my questions. The story is fascinating. You are kind to share your experience with me/others. This information will help me/others as we watch the 3 Hays eaglets this year Fledge. The Pix “Zoomies” will be working overtime. It is extraordinary that Tom Moeller could position himself to get such great shots. I guess he is going to try for an encore this year? With 3 fledging so many more opportunities but he must be preparing to spent a lot of time down there. I will reference your Fledge information/photos Tom Moeller on cam chats if you don’t mind? Does Tom Moeller mind as long as he is cited for photos?
    Best Regards.

  12. Kate St. Johnon 15 May 2014 at 9:16 pm

    John Thomson, I don’t mind at all that you pass along my links. If someone wants to use Tom’s photos they should contact him via his Picasa account.

  13. John Thomsonon 16 May 2014 at 3:40 am

    Thanks Kate. I will just reference you and they will see Tom’s photos when they view your blogs.
    I enjoy Scott Shalaway’s weekly birding articles, “The Wild Side”, in the Sunday Post Gazette/Wheeling News- Register. His weekly radio shows now only Saturdays 8 to 10AM online WVLY AM 1370, AM 1600-s30255/ Wheeling or Wheeling. I am sure you have known him for a long time. As you know he had quite a close call with a trip to the Emergency room about two and a half months ago and thankfully he is slowly recovering and back on the air.
    Best Regards

  14. Debbieon 18 May 2014 at 2:31 pm

    I was wondering if these falcons will be banded and if so when?

  15. Kate St. Johnon 18 May 2014 at 8:51 pm

    Debbie, that will be banded Tuesday 9am. You can watch the excitement on camera or at Flag Plaza.

  16. John Thomsonon 24 May 2014 at 2:07 am

    Kate where can I view the banding? I checked archives on the WildEarth falcon web cam site and there are no archives after 9:00 AM on 5-20-14 Tuesday? Did you mean that they streamed the whole banding and that was the only way to have seen it? I misunderstood you when I first saw your post about the “Surprise” that the Falcon chicks were to have in coming week when they were banded. I thought that the day and time were not released to the public as in the past as I recall? They would just turn the web cam off when they were to begin the banding and when they were done the web cam was turned back on and only some still photos would be posted?
    So I missed it. Were you up in the Gulf Building for the whole thing Kate?
    Oke doke.

  17. Kate St. Johnon 24 May 2014 at 6:59 am

    Sorry to hear the Gulf banding archives aren’t there. See banding photos here: Also note the p.s. at the end of this blog that points to KDKA’s video.

  18. John Thomsonon 27 May 2014 at 4:37 pm

    Thanks Kate. I will check photos and KDKA video.

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