We knew there was something odd going on pretty early on.
The radio telemetry signal was not coming from anywhere near the Cape
Rockjumpers I could see on the other side of the valley by the predawn glow.
One of the birds was the female we knew from the cascades territory, female
blue, named after the blue ring on her right foot. I presumed the male with her
was her mate, the cascades male, and that we were dealing with a case of a
dropped telemetry tag. The birds foraged actively among the rocks, and engaged
in a bit of what appeared to be playful socialization. All seemed well. I lost
sight of them when they flew to the west facing slope, as they headed for the
early morning sunshine which would add some warmth to the morning that had
started at 5 degrees Celsius. Krista got a view on them and carried on the
observations, while I headed back to trying to find the dropped tag, always a
mission when the signal bounces around the rocks, crags and valleys.
After about an hour Krista let me know that she’d lost sight
of the pair of rockjumpers close to where I was looking for the tag. I tried to
locate them, and tried and tried. They were nowhere to be seen. Eventually, we
started a sweep search of the territory. Two hours later, and still nothing.
That was when I started to get worried. We knew these birds, they were always
here. Where were they now? Come to think of it, had there been any rings on the
male bird? Krista didn’t recall seeing any.
Maybe we weren’t just looking for a tag, maybe we were
looking for a tag with a dead bird attached. I headed back to where I had been
looking, and project volunteer Brian brought up another telemetry set. With
this equipment within half an hour I was picking up a strong signal, and
narrowed down my search to a boulder. Putting down the equipment, I peered
around it. There were feathers, lots of feathers, the outcome of the search now
seemed inevitable. A bit more searching, and the red and green rings that the
cascades male had worn were found lying in the dirt, with more feathers and
some bones. Finally, stretching and grabbing blindly under the rock I pulled
out the chewed radio telemetry tag.
Judging by the location under the boulder, together with the
feathers and damaged tag, the cascades male had been killed by a mongoose, and
probably several weeks earlier. It was a sad moment – this was the first male
that I had deployed a tag on, in November of last year. We had followed him and
female blue twice a month for four months. He had become rather relaxed in our
company, often foraging unconcerned within meters of us.
The male we had seen in the company of female blue was most
likely the rival male with whom we had seen the cascades male tussling on most
mornings. One tragedy, another’s opportunity it would appear. We spent the rest
of the day looking out for female blue, but our guess is she’s made herself a
new friend. No time for mourning in nature – you’ve got to get on with life.
So here’s to you cascades male, male 206. Thanks to you we
now know so much more about the secret life of Cape Rockjumpers. He represents the first ever recovery of a
ringed Cape Rockjumper in the SAFRING database.
The following photo of the cascades male was taken by
project volunteer Dr Dean Portelli:
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