I have just spent 3 days in the Sandveld during which time I visited 11 nests. The eagles there seem to be quite productive:
6 - incubating
1 - possibly incubating but not confirmed
2 - chick
2 - Black eagles present but not seen on the nest.
In comparison; in the Cederberg 5 out of 18 nests are being incubated and 2 have chicks.
There are lots of reason which could be played with - in the Sandveld I was mostly told where active nests are by Lucia Rodrigues. Whereas I found about half of the nests in the Cederberg by searching appropriate cliffs so perhaps in some cases I have found old nest structures. However, having said this, most of these sites normally have eagles in the nest vicinity, or in some cases standing on the nest or building it or even mating nearby.
In the Sandveld the nest spacing seems to be further apart than in the Cederberg... but this might change with more nest searches in both areas.
This is all preliminary, but there's some numbers, thought and questions...
Monday, 18 July 2011
I took these photos on the 14th - there's still one egg and the chick must be around 3 days old. This is the first hatching of the nests I have been monitoring in the Cederberg. It's rare for me to be able to see into a nest like this - it was super rewarding to find a little spot on the mountains where I could properly see what was going on. There was fresh prey on both sides of the nest and while I watched the adult came in and incubated the chick. It was magic to be up there looking down at the nest and the valley - an entirely different perspective from hours of neck-straining binocular-wielding from below!!
Tuesday, 12 July 2011
Today I hiked out into Matjiesrivier Nature Reserve with Colin. The reserve is owned by Cape Nature and managed by Rika du Plessis. Together they have a 5 year plan to monitor the breeding success of the Black eagle on and around the reserve. Colin has worked for Cape Nature for an inspiring 20 years and takes pride in monitoring the eagles. He has been monitoring this nest since incubation began in late May.
It’s a unique area of the Cederberg with a drier climate and succulent Karoo vegetation (as opposed to the Fynbos on the western side of the Cederberg). At his time of year there’s some water in the rivers and things are coming alive; pinks and yellows are blooming, rock pools are teaming with tiny tadpoles and bright green new growth is sprouting.
Colin visited this nest yesterday. From the bottom of the valley he could see that the adult was sitting on the edge of the nest rather than in the nest. Today’s mission was to hike to the peak on the opposite side of the valley and see down onto the nest. Although there’s no hiking path Colin knows the valley intricately and led us through a maze of boulders, along the river and up the steep slope to our vantage point.
We arrived and set up our telescopes and zoomed in across the valley. There are three Black eagle nests on this cliff – two of which are amongst the largest I have seen. Sure enough, on the far left nest there was an adult eagle sat on the edge. It had back to us and was looking into the nest. Once focused in we soon saw a movement of white fluff. Without a doubt there was a chick there. We watched the nest for three hours. We saw both adults; which actually spent more time off the nest and hunting than with the chick. When the adult left the nest we had a clear view of the chick. Although it is probably no more than a week old, it was walking (or falling) around on the nest using its small stubs of wings for balance. Looking through the scope at this sight made the whole area feel even more alive. Here was a stage of life which we normally don’t get to witness.
Thank you Colin for taking me to this nest today. I won’t forget my first ever view of a Black eagle chick!!
|Adult on nest... there's a chick in there too!|
Sunday, 10 July 2011
On 5th June I went for a “Sunday stroll” towards Tafelberg. I was soon distracted by a pair of Black eagles which I could see perched further along the valley. I headed towards them and kept following after repeatedly seeing them. They perched together on a rocky outcrop and then mated. Soon after this I saw one flying away with a green sprig – no doubt headed towards it’s nest. I became completely side-tracked from my walk and ended up following the eagles, or heading in the direction I thought they had gone for what turned into a 10hour hike! But it ended well and I finally found their nest!! I noted in my book “nest found – seriously tall!”.
Today I revisited this nest (which in a straight line ironically only took me 30minutes to get to). The sun was behind the nest cliff and it was difficult to see it properly. There was no way of telling if there was a bird on the nest or not and two hours had passed before I saw an eagle. It flew in front of the nest but didn’t land and didn’t give anything away to me. I started to wish I could fly… just so I could see if there was a bird on the nest.
Another hour passed before I saw another eagle. This time it flew across the valley, did a pendulum-like display fight, and then circled back to the nest cliff. Then I could see two eagles. Finally the one I was following darted towards the nest… but flew straight past it… and onto another smaller nest which I hadn’t yet noticed. The pair are incubating! I’ll stick to walking…
Thursday, 7 July 2011
Scott Ramsay has dedicated a year to explore and document the wild places of South Africa. Currently he is spending two weeks in the Cederberg. Yesterday he joined me for a hike - check out Scott's blog to see what he thought... http://www.yearinthewild.com
Tuesday, 5 July 2011
Today I visited three of the nests I am monitoring - they have been incubating for maximums of: 26 / 34 / 45 days. I normally visit nests around once a week. After recording incubation the actual laying date could be up to a week earlier depending on nest visit frequency. Incubation is 44-45days. So this basically means the nest which is on day 45 could hatch any day this week. But to add to the monitoring difficulties, most nests you cannot actually see into. So when the egg(s) (1 or 2) hatch I will depend on the behavior of the adults to find out. It won't be until the chick is larger that I will be able to see it on the nest. By this stage Canism* will have occurred and there will only be one chick.
This nest has failed for the previous two years - 2009 there was a breeding attempt but it was unsuccessful. 2010 a chick was seen on the nest but it did not fledge. The reasons for failure are unknown, there has been speculation that the nest is too low and accessible for baboons... but I don't think I believe this. Although the nest is relatively low, it is on a vertical face. I have my fingers crossed for these two and hope to put a nest camera up to monitor the chick if it hatches and shed some light...
*Canism: the first chick to hatch will out do their younger sibling for food and cause physical injury until death...