Last week whilst working at Thornton Ellers we decided to
check the Ash tree which over the years has been a regular roost/nesting site
for Tawny Owls. Plenty of stealth is required to reach the bottom of the tree
without the birds realising – snap a twig underfoot and you’ve got no chance! Once
there the hand net is put up against the tree hole and with any luck the owl
flies in – it worked on this occasion – thankfully – as the bird we found in
the net wasn’t the two from the previous goes but one which was initially
ringed back in 2000! It was ringed then as a ‘5’ on the 11/03/00 meaning it was a chick the
year before, so we now know that it has reached the age of at least 15!
Adult male - 10/01/14
This is
the oldest Tawny Owl we have on the valley records – you wouldn’t have thought
it though looking at him with pristine feathers and alert eyes watching our every
move. Tawny Owls are sedentary birds, seldom moving far. From the seven
recoveries we have from birds ringed in the valley, four have now been
re-trapped or found dead within 100 metres of the original ringing location.
One bird moved the 4KM from Sutton-Upon-Derwent to the Wheldrake area whilst
the two longest recorded movements are of 12 & 14 KM. Last January (10/01/13) we ringed a new male in the same Ash tree, which we wondered if it might be the mate of the female ringed in the same tree hole in October of the same winter (30/10/12).
Adult male - 10/01/13
Adult female - 30/10/12
At present the local
Tawny Owls are becoming increasingly vocal, which reflects the fact that they
are traditionally early nesters, one individual has been heard recently around
the NNR Base. In previous years birds have been found at this time of year
already incubating clutches or even with young chicks. Tawny Owls like a lot of
owl species had a very poor year in 2013, so it’ll be interesting to see how
this year unfolds…..hopefully for the better.


No comments:
Post a Comment