Thursday, April 14, 2016

Bald Eagles hatch second brood-- BUT...

Sunrise over the entrance to our local wetlands:

Sunrise at gate HDR 20160407

The rainy "dry season" has been followed by more typical Spring weather. Morning clouds carry a promise of even more rain:

Looking west before sunrise HDR 20160407

As related in this earlier post, Bald Eagles trying for a family again, our local Bald Eagles failed to breed last season during the winter of 2014-2015. The new female of the pair was young and inexperienced and never seemed to exhibit a brooding instinct.

Bald Eagles usually breed only once in a season, as the rearing and training of an eaglet takes about 4 to 5 months after the egg is laid until it gains independence. Second broods occasionally occur if a nest or eggs are destroyed early during incubation, and rarely after the loss of eaglets. 


However, this year, because of unusually severe weather during January and February, 2016, several pairs of Florida's eagles have produced second broods. Our local pair hatched out at least one eaglet but it was probably injured and lost by January 20. 


This season, Jewel, the female of the pair, laid her first egg on or about December 13, 2015. This egg was expected to hatch in 5 weeks, around January 17. Unfortunately, several severe thunderstorms with winds up to 80 MPH roared through in January, depositing broken branches over the right half of the nest. Since the nest tree is a very limber Australian Pine, the wind surely whipped it about severely. This photo shows damage to nest on the afternoon after the January 17 storm. Adults kept sitting on the nest and tried to move the fallen branches:


Bald Eagle female after storm 20160117


On January 19 there was clear photographic evidence that at least one eaglet had survived the storm and was being fed by Pride, but this was the last sign of life in the nest:


Bald Eagle male feeding nestling 7-20160119


Presumably the newly hatched eaglet sustained injuries which proved fatal, and any other eaglets or eggs were lost. The pair of eagles never abandoned the nest area and the male spent much time sitting in it after the loss of the brood. Then, on January 29 I saw Pride attempting to mate with Jewel:

BaldEagle Pride flies to Jewel 2-20160129


BaldEagle Pride mounts Jewel 3-20160129


In mid-February the eagle watchers reported that an adult was persistently sitting deep in the nest, suggesting the possibility that a second clutch of eggs had been deposited. Then, on February 16, another swarm of severe storms swept through, depositing a second and much larger branch on the left side of the nest. Look closely at this photo and see that an adult continued to sit deep despite the new damage: 


Bald Eagle on nest post storm 3-20160216


The eagles stayed on the nest and we feared that the male may have been sitting on one or more infertile eggs, but then both of the pair appeared to be incubating and our hopes were renewed. On March 16 both eagles were seen peering into the nest. They often do this when the first eaglet hatches.  


On March 17 we received photographic evidence of at least one eaglet in the nest. I took this photo of them feeding a new offspring on March 24th:


Bald Eagle feeding 02-20160324

Bald Eagle feeding 04-20160324


There were actually TWO eaglets seen in the nest by April 2. One eaglet was more active and aggressive:


Bald Eagle eaglet HDR  2-20160402


The other was smaller and had more natal down:


Bald Eagle eaglet HDR20160402


The older of the two appeared to be about 2 1/2 weeks old, suggesting it may have hatched on or about March 16. This meant that incubation of the second clutch of eggs began 5 weeks previously, around February 10, just before the second storm blew the other branch down over the nest. They have survived so far despite the adversity.


Here they were on April 7:


Bald Eagle 2 eaglets 2-20160407


Pride was guarding the nest and flew down to check on the eaglets:


Bald Eagle male Pride in flight 20160410

As we watched the nest, a family of Raccoons decided to cross the busy highway. We held our breath but they seemed wise enough to wait for a gap in the stream of vehicles:

Raccoon family crossing Pines 20160402

One youngster (almost fully grown) was reluctant and lingrered behind. 

Raccoon straggler crossing Pines 20160402

After a couple of false starts, it scooted across safely, just ahead of the traffic: 

Raccoon straggler crossing Pines 2-20160402

As I was ready to publish this, I had to add the big "BUT" to the title... 

I posted this photo in my Bald Eagle Nest Watch FORUM on April 10, showing the older of the two eaglets. I was concerned because its aggressive behavior towards its nest-mate was quite obvious. I assumed that the younger chick was hiding but asked others to look for it and keep tabs on its welfare:

 Bald Eagle - one eaglet in nest 3-20160410

My concerns were justified the very next day, when one of the watchers actually saw and photographed the eaglet being attacked and killed by its sibling. Here is a link to her report of the horrific event. Scroll down to Kathy's post:  One eaglet seen in nest -- other has been killed     

In the event that you cannot bear watching this, here was my response:

!t is very sad to learn that the older and more aggressive eaglet killed the younger one. I feared it was being cowed into laying low or even already injured by the older one when I posted my message. Siblicide is one of the eagles' keys to success, as it gives the surviving eaglet a much better chance of becoming an adult.

As you may know, the first eaglet is more likely to be a female than a male, and she is larger than the male at all ages.  The second is more likely a male, so there is a 1:1 sex balance. The first-hatched, if a female, is more likely to kill a second female, perhaps because it eliminates a competitor while she is still small and weak.  A female and male sequence is the most successful combination for survival, maybe because the male learns his place in the hierarchy and does not challenge the female. This also assures a balance between the number of males and females as adults. If the first-hatched is a male the entire brood has less chance of surviving than if the first is a female.

Since south Florida eagles developed an instinct to breed much earlier than those up north, there were inherent advantages-- less heat stress on the eaglets and better prey availability when they are growing fastest in February and March. Let's hope that Pride and Jewel can provide for the single eaglet and see her fledge successfully sometime in late summer. 


= = =  = = =  = = = =  = = = = =


Linking to Misty's  CAMERA CRITTERS,


Linking to Eileen's SATURDAY'S CRITTERS,

Linking to GOOD FENCES by Tex (Theresa). 

Linking to SKYWATCH FRIDAY by Yogi, Sylvia and Sandy

Linking to WEEKEND REFLECTIONS by James

Linking to BirdD'Pot by Anni


Linking to Wild Bird Wednesday by Stewart


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Please visit the links to all these memes to see some excellent photos on display


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24 comments:

  1. ohhhhhhhhh what wonderful captures.

    I love skyscapes

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  2. Hello, I love the gorgeous sky shots. Awesome series on the Eagles and their young. It is sad that one eaglet can kill it's sibling. Happy Thursday, enjoy your day!

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  3. Awesome eagle shots and love the raccoons too!

    Happy Weekend coming to you ~ ^_^

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  4. When I was reading it I had forgotten about the BUT at the beginning but then that is nature working correctly. I wonderful story adn photographs toillustrate it and I am sure you will keep us informed with the progress of the remaining click kenneth.

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  5. Brilliant captures, Kenneth! I also love your eagle header and beautiful green background!

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  6. You are spot on Ken. The lateness of hatching(for Florida) probably caused the food supply to be not ideal and not enough to support two. I suspect the bigger one didn't actually "kill" the second one. It was pecking at it to show dominance like they do and the second one was too weak to take it. Sad but this is nature.

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  7. Such a lovely sunrise over the wetlands. The raccoons were just so cute and those eagles are amazing. It saddens me to hear that the one killed the other one but I guess that is "nature's way." - I'm curious as to why their nest area can't be cleared to make it safer for them.

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  8. very sad, but i hope the stronger one will survive. i had 2 raccoons run out in front of my car this week, too.

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  9. What a story of those eagles!
    The sky photos are gorgeous.

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  10. I hate to hear that one did not survive, but hopefully the second one will. Well, actually, I guess more than one didn't survive, if you consider the entire spring.

    Oh, that sunrise sure was awesome.

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  11. Impressive sky and cloud reflection. Love seeing the eagles and the new eaglet.

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  12. Phantastic pictures and a gorgeous reflection of the clouds!

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  13. The reflection photos are top notch and I love the eagle photos too.

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  14. excellent photos....
    As an aside, a photo has been circulating with about 20 eagles sitting in a tree in a town about an hour north of where I live....Are you on facebook or instagram?? if so, search for Stan Enns to see the photo. I think they are part of a group of about 50 eagles that are still migrating north.

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  15. Hello ken, awesome post. I love all the eagle photos. Those darn raccoons are a problem here, I have to put my bird feeders away every night. Thank you for linking up and sharing your post. Have a happy weekend!

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  16. Stunning shots of the eagle, love seeing your pics.

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  17. That first pic is fantastic.

    The eaglet story is fascinating. "Nature finds a way" as the story goes...
    ~

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  18. Oh............I am heartbroken!!

    Hope you have a terrific week ahead, and thanks so much for participating and sharing your birds for us at I'd Rather B Birdin'.

    Tho a sad outcome, I know, it would eventually find death because of being the 'weak link' of offspring I guess...but still. Excellent commentary Ken. And wonderful updates/showing the progress with photos.

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  19. Hard to respond to things like this without the use of the word cruel - but I suppose it's just nature.

    A good - if sad - story (if you see what I mean)

    Cheers - Stewart M - Melbourne

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  20. Your posts would make an awesome book! They are fascinating to read and see the photos! How exciting there was a second brood, but then sad about the death of the smaller male chick. Nature is so harsh! But, it is the way it is. I look forward to following the new chick in her life!

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  21. Eagle lives are fraught with danger right from the beginning it seems. "Ours" so far are still doing OK -- the older eaglet has taken several flights and the younger is doing hops and wingersize on branches. ( can't seem to get good pictures, but I've seen them both. (The younger one is the one that was rescued by Rehab and returned to the nest...which still seems like a miracle.)

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  22. Gorgeous skies and the raccoons are cute. I love the eagles. Let's hope the remaining eaglet will survive.

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