Wednesday, 12 March 2014

Owl together now

It has been a great privilege to overhear what I can only describe as an operatic love affair worthy of Tristan and Isolde, between two Tawny Owls [Strix aluco] Chouette hulotte. But it is as though we are listening to the opera on the radio. We have never seen any of the protagonists, but we have heard them up to three times a night for the past six weeks - and the drama is by no means over yet. In the absence of any of our own pictures, here is a wonderful picture by Martin Mecnarowski from the Czech Republic.

Copyright Martin Mecnarowski under Creative Commons

We have learnt a lot about Tawnies, their behaviour and particularly the sounds they make since 16th February, from both literature and observation. I basically knew that the females calls "kee-wick" and the male goes "tu-whooo". ""Tu whit tu whoo", the merry note of Shakespeare, is not the call of one bird but the combined contact call of a pair. I learnt that they mate for life (only four or five years on average in wild birds, though a captive bird reached the age of 21) so it's to the female's genetic advantage to form a bond with the best male possible. What the literature doesn't say is that she initiates the process (in our hangar in this case) with screeches and trills of high excitement when her hormones reach the right state of readiness. Mid February is a typical time for this to happen, when she is about 9 months old. The four males that responded may not all have been the same age, and on 4th March she kicked off a response from what sounded like eight males - probably every male for miles around.
Her "kee-wick" calls were loud and carried a long way.
However the trill, though soft and musical, does not carry. It is supposed to only be audible over some 50 metres. It is rare for humans to hear this trill from a wild bird, and there is only one recording of it on Xeno Canto out of 188 Tawny Owl recordings [I've put that in lower down].

One male (bolder?) came into the hangar to call for her, several nights running. She called out with regular shrill "kia" noises, and he hooted in reply to make up the "tu whit tu whoo". I recorded these calls with the voice recorder on my veteran Nokia mobile phone. At the time I thought I hadn't got anything. It was only when I downloaded these recordings that I realised that they actually aren't too bad. The tricky bit of this was to get the recording out of the phone. and onto something that can process it. Nokia's software doesn't do it - in the end I just treated the phone as another storage device, found the recordings with Explorer and copied them to the computer.

These are the Nokia recordings from just after midnight, 16th February....
first the female calling "kia" and the male hooting gently


and again 



His lyrical hooting calls contrasted with the fortissimo blast he gave one night in challenge when another male had the temerity to respond from outside. I was standing in the barn listening in darkness, and I didn't know the doors to the hangar were open! She too was outside, moving around probably from one telephone/electricity post to another.

After that we heard them flying up and down the valley several times per night, she leading, he following, stopping briefly in a tree or pole to call to one another. 

The owls were also coming together for more intimate meetings, and some of these were in our hangar. After numerous attempts I managed to make a recording of the trilling call, this time being made by the male. It's recorded on an I-pod using a microphone intended for voice memos. The quality is awful, with a lot of white noise, and it failed completely to pick up the female's high-pitched call. The Nokia is much better quality, albeit fainter.

First we heard the female calling, then the male replied with some gentle hoots. Then (30 seconds into the recording) he started to trill. She continued to call, although that didn't record. You can just pick out the trill, particularly in the later part of the recording.
Unfortunately, this recording is extremely faint and crackly...


but this one, from XenoCanto is somewhat clearer


We continue to hear them on their nightly rounds of the valley, and at dawn we hear the male calling from the direction of the river. It is very probable that they will breed, although we don't know where - they may take over the barn owl box. Then we might see some of these...
Copyright: Twearth.com-species-tawny owl (under Wiki Commons)

4 comments:

Sheila said...

How exciting...doesn't sound as
though you've been getting much
sleep! Let's hope they do nest in
your barn. I find owls to be such
fascinating birds and love to hear them hooting near us on occasion.

Amelia Frenchgarden said...

The recordings are brilliant, especially for someone like me who would not even have recognised them as owls. Now I might recognise the sounds if I ever heard them. Owls are beautiful, fascinating birds, I do hope they choose your hangar to nest in. Amelia

philipstrange said...

Thank you, I learnt a lot

Pollygarter said...

We learned a lot too! We heard the male trilling again last night and I was sitting by the door - didn't dare move in case I disturbed them.

The trilling record may be too big to load on some computers and we're going to have to edit it.