Since we have been
living at Blue Hill, perhaps on alternate years Jackal Buzzards have
nested in cliffs not far from us. Jackal Buzzard is one of the
world's most strikingly beautiful buzzards, and a South African near
endemic, where it is relatively common.
I was interested to see
what prey items were being delivered to the chicks ever since one of
the farmers in our community mentioned that Jackal Buzzard were
killing their pigeons. Camera traps are allowing us insights into the
most intimate of nature's secrets; and are frequently used by a range
of researchers to document life histories at raptor nests: Black
Sparrowhawk and Crowned Eagle recently the focus of two PhD students
in South Africa.
I installed a Bushnell
motion sensor camera on the nest at 10:30am on 14 October. There were
two small fluffy white chicks, which I did not photograph as I wanted
to minimise disturbance and leave the area as quickly as possible.
I'd later regret this: an insight into the chicks health at this
stage would have been useful for unraveling the mystery of what
happened over the course of the next few days. Already at this early
age it was clear that one was not going to make it, with one chick
twice the size of the other. Cain and Abel-ism is a common, somewhat
disturbing, aspect of the reproductive cycle of many raptors: the
first born chick kills or out-compete younger siblings.
Within minutes of my
departure the female had returned to the nest.
Over the course of the
next few days several interesting prey items are observed including
one small bird (possibly a chick), a large bird (possibly Red-winged
Starling), several agamas and a sungazer lizard, two snakes, a small
mammal and a Sengi.
Prey item: small bird. Also note the temperature is cold at 6 C |
Prey item: large bird (possibly starling) |
An unexpected visitor while mom is away |
Southern Rock Agama feature several times |
Snake |
Sengi (Elephant Shrew) |
The weather was
extremely variable over the week of action captured, from below 5 C
to over 35. Panting and wing-drooping, behaviour associated with heat-stress, are observed from temperatures starting in the mid- twenties. The brooding female has to endure hours of hot afternoon sun.
There are very few
photos of the chicks due to the angle of the camera.
On the second day the
smaller chick is still alive, but the photo below looks like the mother
disposing of the youngest chick (subsequent photos in the following seconds after this one show the adult flying away).
But all is not well.
This photo reveals damage to the head of the remaining chick.
Damage to the face and head of this chick is reminiscent of recent photos of attacks on seabird chicks by rodents. |
This is the last photo
of the chick, which looks to be carried by an adult.
After this photo adult
Jackal Buzzard visits are rare: in one an adult is carrying a stick –
nesting material – but whether it is rebuilding or recycling is not
clear.
Other species are quick
to usurp what is left of the abandoned nest.
Greater-striped Swallow are seen collecting feathers for nesting material |
Egyptian Goose frequently adopt abandoned raptor homes, but this individual did not stay long. |
too bad . The temperature swings alone sound pretty stressful.
ReplyDeleteInteresting observations Alan. Glad you left the camera on after the nest failed. Might be worth live-trapping at the nest to shed light on your mice hypothesis?
ReplyDeleteInteresting observations Alan. Glad you left the camera on after the nest failed. Might be worth live-trapping at the nest to shed light on your mice hypothesis?
ReplyDelete