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Zandvlei Trust Western Cape Raptor Research Programme Bladen the Black Eagle.
April 2005 The begining of another hatching process! by Lucia Rodrigues Follow this story as it develops ..... 07/12/2005 Lucia
reports "Bladen was last heard calling through the mist on Monday 21st November. On three subsequent visits to the Noordhoek peak area, I have only seen the two adults. 31/10/2005 Lucia
reports "I walked along the contour path to see if I could make sense of what a pair of Jackal Buzzards were up to.In order to get there I have to walk past
a peak. Bladen habitually sits in a dead tree at the base of this cliff and has of late developed a different call whenever he sees me. He probably does this for every human that he spots walking by. 26/10/2005 Rob Kamstra reports "I was hiking coming down from the mountain at about 3 pm. I had best black eagle sighting ever. Nearly ran for cover. Two adults and a juvenile, above the path and below, doing aerobatics and frequently returning to fly very low over my head. In particular the juvenile was very bold/inquisitive. They were very vocal. Again particularly the juvenile. I thought at times they might attack me and became quite nervous. It continued for about 15 minutes, and we went our ways". 20/10/2005 Peter Steyn reports; "10h10 Arrive at observation ledge with birdwatcher from California. 10h20 Bladen makes a spectacular circuit and swoops onto a ledge 25 -30 metres below nest. Bare patch of soil, yellow flowering bush identifies it. Persistently buzzed by one of those red hawk things Anthony studies - must be a nest nearby. Bladen lies down and relaxes but kestrel still misbehaving. Tag intact and very visible, good job! 10h30 Both parents fly in from the Cape Town side, female carrying prey. Land on ledge beside Bladen who grabs prey, a good sized three-quarter grown dassie and mantles over it. He starts tearing at it and BOTH parents stay on ledge watching him. Then they chill out and relax completely, preening etc. while Bladen munches on. Rockies try a few more dive-bombs at adults. Adults remains completely relaxed and Bladen eventually exposes the meaty flesh and eats away. 11h30 No change in activity, Bladen still munching, so decide to leave to show friend view from top of Noordhoek peak. 11h45 On way down from peak I went back for a quick look to find female eating prey with Bladen looking a trifle nonplussed over her shoulder. Left after a few minutes with female still feeding and all three on ledge in perfect amity. This is post-fledging behaviour I've never seen before as, usually, once the prey is delivered the parent(s) push off and leave the juvenile to it. Friend from California totally gobsmacked, as he should be. Here endeth the lesson according to Saint Peter". 22/09/2005 Lucia reports "I
stationed myself below the nest today from about 12h00 to 16h00. 29/09/2005 Lucia reports "Bladen, whom we assume to be male because he weighed 0.9 kgs less than Argo, (males are always smaller) fledged at 79 days on the 20th August. 12 days earlier than expected.
When I eventually found him on the 29th after having heard him call on previous visits, he seemed to be in the same spot I had heard the calls come from before. He also did not budge when his parents flew in with food, which led me to believe he had floated down from the nest and stayed put for the next 10 days. 29/08/2005 Lucia reports "I had a deeply satisfying day, today. I have just realised that it is exactly a month (and a day) ago I had the first full day vigil. Wind 0 to 1, what seemed to be NE in the morning and NW towards late afternoon. The "clouds" high and lightly streaming were moving from the NW all day. Cloud cover was practically 0. Temperature above 10 degrees when I started out and probably got to about 15 degrees, but only by mid to late afternoon. 07h00 reached the saddle. From here on in, events overtook me and my careful note taking went awry. This is how I remember it. Watching the busy little rockie flitting about, came round the corner fast, somehow must have forgotten about the perched BE, as it seemed to take last minute evasive action. The BE certainly gave no sign of having even noticed it. Suddenly the second adult appears carrying food!!!!!!! Although impossible to confirm, my guess is that it was dassie. Both adults flew into the ravine. I dropped everything and scrambled back up the slope with my scope and bins. Bladen started calling!. The little bugger had been there all morning, as silent as a churchmouse! By the time I got to the spot I was earlier, the adults were flying out of the ravine again, one adult still clutching the prey. Bladen still calling lustily. I could not see him. They flew back in again, this time settled on a rock, (which I discovered later was about 30 meters below Bladen's position) One of the adults started pulling at the prey, not sure if s/he was eating.
Both flew out again, with the prey, then as before within a minute or two flew back in for the third time.
This time straight next to Bladen. I did not realise this at first because he was so well hidden, behind a thick clump of vegetation! It was a beautiful sight to see both adults sitting together on a low oblong rock close to where Bladen was feeding himself, keeping a watchful eye on the surroundings. He was still almost totally obscured by the vegetation, calling and eating, calling and eating. I could alternatively clearly see his bright yellow beak, russet crown, a bit of tail and wing, (with a flash of orange tag), as he rocked back and forth eating. It took a while for him to settle down to this routine. Just after the food had been given to him he stepped about in an unsteady fashion with semi raised wings. He ate for over two hours!! During this time I heard a dassie alarm call once. A single Rockie flying about, lower down this time, harassing a Rock Pigeon off a ledge. There is a fair bit of rock pigeon activity on this cliff. I was not able to establish if there is a specific spot the Rockie was interested in, but will be back to take another look. I never heard any rockie calling during the day. After about an hour or so, one of the adults flew off the rock and back up to the perch it was on before. I think it was probably the female who stayed behind. I made my way down to my backpack and saw it was 17h27. Looking back up, I saw that the female had come off the rock as well. She was eating herself and alternately still feeding Bladen. For the first time Bladen stepped clear of the vegetation and I could see him in his full glory. Truly a most beautiful eagle. The patagial tag in perfect position.
Lucia with "Bladen" see the yellow wing tag. Then I looked up, the male had disappeared from his perch. I left Bladen, who was again obscured by vegetation, with mom and headed back for my car. What a day! By contrast the stunning sunset paled into insignificance, although a fitting end to a wonderful day". 28/07/2005 Hi all, had a wonderful day.
Lucia reports "This is a long winded account, typed up more for my own record than an expectation that it will be read by others.Weather clear, sunny and warm. Light easterly that sometimes seemed westerly and at other times dropped away completely.
Black Eagle parent sitting nearby. 12h35 chick comes from under the ledge and lies spreadeagled. Its wings are entirely feathered, crown and nape russet, cheeks black, legs look strong and fully feathered in cream, huge pale yellow feet, serious black claws. When lying down his feet are curled up in a relaxed manner. The rump still seems white and fluffy.
"Bladen" with his big yellow feet. 12h50 suddenly noticed the female on an uncomfortable ledge below the nest, she jumps down into the middle of a fynbos bush, sits there for a minute or so, makes no attempt to pick any greenery, I hear her call before flying off to the same perch north of the nest.
"Bladen" before he was wing tagged. Also note the feather colouring and background rock and dry vegetation colouring to help camouflage him at this vulnerable time. 14h20 female has hopped off her top rock to about 6 feet lower down next to a rockpool of water. I heard no raptors calling besides the 2 occasions the female BE gave a brief call. Never heard the chick call either.
Other smaller birds about were Rock Pigeon, Redwinged Starlings, Rock Martins, Orangebreasted
Sunbirds, Cape Siskins, Familiar Chats, GWP 07/06/2005 Peter Steyn relates the following observations with 3 other people in the group; 09h50 Arrive at my usual observation ledge and the chick is lying in the middle of the nest in a prone position.
Soon after our arrival we discovered, fortunately without flushing her, that the female was perched on the edge of the cliff, just 20 - 25 metres from us (i.e. to right of observation point OP). We peeped cautiously at her, and she stared back imperiously, with no intention of giving up her right to perch priority. She was completely relaxed and even preened. She knew we were there and could hear us talking, but was completely laid back.10h47 Sun reached middle of nest, and chick. It disappears to back of nest where it is not visible from the OP. 11h05 Chicks emerges, stands, defecates, walks round briefly and disappears to back of nest. Chick's crop is empty. 11h55 After 2 hours on perch near us female flies off, perches briefly on ridge, and then disappears. 14h10 Female reappears for first time in 2 hours and flies back and forth in front of nest but shows no intention of alighting. No calling from chick which should be ravenous by now. 14h20 Female flies out of sight. 14h43 Female reappears flies back and forth again and low over our heads and disappears at 14h47. 15h00 Chick emerges, stands and defecates for only the second time. Then back out of sight at back of nest. 15h05 Brief sighting of female. 15h15 Ditto 15h40 Both birds appear and male carrying a dassie (the first time he has been seen all day).
15h43 Female lands on nest and chick emerges into shade beneath her. 15h47 Male appears to be having trouble landing at nest (it was an almost windless day) so female leaves nest and they disappear from sight. 15h50 Female onto nest with medium sized dassie, partially eaten but head intact. Male flies out of sight but this was the first time the entire day that the Ravens appeared - do they follow hoping for scraps? 16h00 We leave female plucking dassie and starting to fed chick. Postscript: It appears that chick can be left unattended, female's behaviour did not suggest we were a factor, and he was out of sight most of the time at the back of the nest. Kestrels appear to be prospecting for a nest site in the area, this needs to be watched. 05/07/2005 Ann Koeslag took this picture below today, when visiting the site.
Chick about 5 weeks old now. 07/06/2005 Today, I received word from Rob Simmons that the second chick has hatched. This is about four or five days after the first chick hatched which is the same interval the two eggs are laid. As you know in Black Eagles, only one chick survives because the older chick brutally bullies its younger sibling by pecking it and taking all the food offered. Strangely the adults do not intervene. Although theories abound, scientists still do not have an explanation for this phenomenon.
The second chick has hatched from the eggshell on the right. Rob Simmons reports on his observations; Arrived 9h45. Cold front ominous to NW, cold (10 -12oC) wind 4 out of 6 strengthening. Waterfall droplets going upwards! Took a picture of Anthony v Zyl looking through vibrating scope. 9:45 Female on nest brooding, no male seen. Female looking wet, shifting suddenly and looking down every 2-4 mins. Presume in response to chicks. 2 small-medium dassies on nest ledge, largely untouched.
10h00 Male in to area with small-medium dassie, landed ledge below nest, female calling, off nest revealing 2 chicks for first time - egg shell of second, still evident. Down sticky on back of Abel (2nd) suggests 10h35 Feeds Cain for about 5 min from the fresh dassie, none given to Abel but he is not interested - head down most of time (asleep?). No aggression seen. Egg shell still in the nest. Female re-settles on chicks on finishing feed, 3 dassies on nest. She continues to jump while brooding, looking down as Cain moves just under her breast feathers (seen from time to time). Wind seemingly not striking nest as females feathers rarely ruffled. Updraft is intense and may "protect" her. 11h10 Too cold to continue (even my dog is shivering). The female still brooding, weather threatening and wind up to 5. Dungeons waves looking huge and some surfers out there looking like ants in a bath!
Watch: 85 min, 1 prey item, 1 feed of about 5 min to Cain only. Abel is likely to disappear in the next few days and I would like to know, how much aggression is shown to him/her if anyone can get up there. 05/06/2005 Ann Koeslag reports that she could not identify the carcass being carried to the nest by the bird on the left, below.
The bird on the left is carrying a carcass to the nest.
The carcass can be seen in front of the chick, the second egg is behind the chick. 04/06/2005 I am delighted to be able to report my visit to the nest
today, confirmed the first chick had hatched. The weather conditions on the previous 3 days were so bad visibility was 0, therefore I cannot be sure when this first chick hatched except to guess it could have been the 2nd June which was the same day Argo hatched last year! 14/05/2005 Arrived at 13h00. The
female was incubating. A couple of minutes later the male arrives, flies a few
circles before disappearing. The female shows no reaction and calmly continues
incubating.
The male on the nest with the pine needle sprig 14/05/2005. 14h45: Male reappears, flies about and then to a
small vegetated rocky outcrop. I first thought he was picking some greenery, but
upon closer inspection saw that it was a piece of food he/they had cached there.
He picked it up, flew down to the sandy ledge just below the nest where he ate
all of it. During this time the local pair of Rock Kestrels flew about on two occasions in the presence of both Black Eagle's. Both parties seemed to ignore each other. 10/05/2005 Ann and Lucia were at the nest site, and after Lucia had to leave, Ann got a photo of the female with the two eggs. A while later it went off and returned with some greenery to reline the nest.
The female at the nest with the 2 eggs. Returning to the nest with some greenery. 03/05/2005 Ann Koeslag took Heather Howell and Tish Foyle up to monitor the eagle's nest this afternoon.
Ann and Heather very apprehensive about sitting so near the steep drop, in the gusting wind on the mountain.
We arrived about 2pm. Just before getting to the viewing place, both birds passed us by on the wing but when we arrived and could see the nest, one was already back on it.
The other bird arrived and during the change over we could see both eggs. The leaving bird (who I am sure was the male) disappeared. The bird remaining on the nest tidied sticks within her reach.
Later the male came past, disappeared into the cloud, reappeared before disappearing again.
A while later we spotted him sitting on the cliff south of and below the nest. 19/04/2005 I can confirm that there is one egg in the Black Eagle's
nest. Rob Simmons comments Great News, and good timing! Sunday up to about 11 am, we (Ann and I) can confirm no egg.
When I arrived at the nest the female was sitting tight. My first thought was, an egg had been laid, but could not be sure. A little while later she got up to turn around and that is when I saw the egg for the first time. A moment later I understood why she turned around, for the male had arrived bearing the gift of food. As far as I could make out, it was the remains of a Dassie. Lots of flapping pelt led me to assume this. Because of the roaring gale the male held his wings in a tight E and swooped about in the wind for a bit before disappearing against the cliff below me, where he deposited the food. The female left the nest, calling softly and both birds proceeded to swoop around, sometimes hanging in the wind with their legs down and tail up, wings in a tight E, then by simply tilting forward they would swoop down at great speed, but only for a short distance, before rising up again. This only lasted for about 5, maybe 7 minutes. The male flew to the nest and I lost sight of the female, who I presumed had gone to inspect the food. 24/04/2005 The Black Eagles have laid their 2nd egg. Unfortunately I could not get to the nest on Friday and Saturday. The weather was so bad that visibility was nil and it was totally impossible to see the nest. I badly wanted to peg down the exact day the 2nd egg was laid, but the best I can do is between 13h30 on Thursday 21st when they still had one egg and 13h30 Sunday 24th when I saw the 2nd egg. My guess is that it was laid on either Friday or Saturday which is the 4th or 5th day since the 1st egg, which is the normal laying interval. Please contact Lucia Rodrigues with any sightings of Black Eagles.
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