Tuesday 29 January 2013

Osprey eats Raptor...


Looking out of the bedroom window this morning I spotted the Buzzard [Buteo buteo] Buse variable I call "Osprey" busily eating something near to the field seed feeder...

Busy feeding... the white line is feathers!
I went into the guest room to try and get a picture that wasn't through the willow...
But these were the best I could get [at 800ASA in the poor light]... here it is pulling hard at some flesh.

First thoughts were that it had got a pheasant...
but we could see all ten of the Dopey Dorises...
had it taken the Jeremy?

Seven of Ten... the Dopey Dorises under the feeder...
I thought not... the trail of plucked feathers were too white... and then I saw the Jeremy in the field the other side of the Aigronne, parleying with some crows.
were there eleven females around then?

These two shots show why I call it Osprey ...
...the position of the white on the breast and head, front and, here, back... coupled with the colour of the wings...
make it look very much like an Osprey [Pandion haliaetus] Balbuzard pêcheur when it is upright on a post...
 especially by the étang!!

I wasn't going to investigate quite at that moment.... the rain was drifting in sheets across the meadow, in the strong winds!
The buzzard wasn't at all worried by a little rain... it just kept on feeding.
It was there for around an hour... eating all the time.
It then stood there... open beak and hanging wings... panting... trying to cool off...
[all birds do this after a very large meal... their metabolism is such that they heat up very rapidly after a good feast]
... before flying up into a carefully "fallen" tree...
where it rested a while before flying off.


When there was a break in the rain, I put my boots on and went to inspect the kill...




As you can see from the last of the above pictures, it was no pheasant...
not with feet like that!

It was a Barn Owl [Tyto alba] Effraie des clochers... possibly the one that was using our "donkey shed" this summer... who knows?
There was certainly nothing that could be described as identifiable remains of that one...
it was quite a dark morph... but you'd need more than was left here to see that...
the buzzard had eaten all but a few feathers, the pelvis and the feet!

It had also left the next pellet / stomach contents...

I found this when I moved some feathers... so I'm pretty sure that it doesn't belong to the Buzzard.


...that will give me a clue as to what the owl was finding...
not much probably, there are beetle wing cases in the pellet...
the whole valley is thoroughly water-logged...
it's no place for voles!!

There has been standing water since Christmas in all the grazing meadows...
the places that the owl is most likely to hunt...
and in the ploughed [and in some cases, planted] fields that are also in the flood plain...
there are vast open areas on "the tops"...
but even there, you can see the standing water!

This is a hard time for the night raptors that have a major diet of voles...
it is probably bad for the Little Owl [Athena noctua] Chêveche d'Athéna that lives up by Bezuard...
there will be few insects available...
it will be having a "diet of wurms".

If as I suspect, there has been a crash in the vole population....
it is the top predators, in this case raptors, that suffer first.

Our cat has only managed a couple of voles since Christmas...
and just before the last snow, the local Kestrel took a bird as prey off our front door.
So their pickings are meagre...
Baron has his tinned food and the Kestrel has switched to birds.
You should see them scatter when it is about... normally they ignore it!

The Barn Owls are unlikely to try that...

The Tawny Owl [Strix aluco] Chouette hulotte is probably OK up there in the woods...
there will be field mice around...
and possibly Bank Voles...
and probably an "invasion" of water displaced refugees...
so it is sitting pretty!

The Barn Owl can probably hunt on the fringes of the woods...
but it would not be instinctive...
so it is most probable that the poor Barn Owl here was either an older bird...
or one of this years young [the dried feathers will give me some idea]...
but, either way it would be starving and may have succumbed in the last snowfall.

The Buzzard is a well known scavenger and saw its chance of a good meal in hard times.

We can feed the small passerines, and some of the more adaptable insectivores...
the Robin was using the fat balls last year in the freeze...
but there is no way of feeding the raptors...
other than making sure there is a supply of passerines for those that will take them.

So, sad though it is, we will probably see fewer Barn Owls around next year...
they start breeding early in the year and, unless vole numbers increase rapidly...
they won't be able to feed two or three owlets...
so it will take a few years for a good population to build.

Apologies if you found this upsetting... believe me, I did when I discovered that it was a Barn Owl... 

but that's life... and our valley will find more Barn Owls coming by! In fact I have a very large nest box to put up... a Barn Owl box... it will be going in the trees by the Aigronne.

On a lighter note the "smell chequer" didn't recognise passerines... 
it wanted me to put pessaries!

6 comments:

GaynorB said...

Good morning, Tim.

A great post. Upsetting but a really fascinating analysis of the state of the bird life in Aigronne valley.

Great pics.

Only another 8 weeks....

Susan said...

I'm glad it's not just me that looks at some buzzards and wonders if they are an osprey. I agree that the voles in their burrows have copped it in all this rain. There must still be a few around though, as I saw a fox pouncing in a field the other day (just before I fainted in fact!) Sad about the owl, they are lovely creatures. It is most interesting to see the feet close up in your photo.

Tim said...

Susan, they are not called the Buse Variable for nought... I think the French name is far more apt! I've just been watching the Kestrel ground-feeding... hopping and walking along the ridges in the field opposite... and then making a short [3m or less], ground-hugging flight to another ridge... behaviour more typical od a Little Owl... and I think that the reason we are seeing the male Hen Harrier here almost every day, is that it has had to widen and repeat hunt its territory.

Gaynor, thanks... I will always report this sort of thing here because it is part of real life.
In feeding the small birds, I am aware that some will be food for those further up the food chain... but that's a food chain!

Niall & Antoinette said...

Even here the vole population has dropped using our "Shadow-meter". He hasn't brought one in for ages and usually he's pretty regular. All our ground is very boggy and we have standing puddles.

Love barn owls so it sad to see. On the bright side here the gold finches have now appeared at our 'table'.

As you say--nice or not it is a food chain.

Tim said...

Yes, I think it is as bad on the flat tops of the ridges as it is in the valleys.... there are very likely only vole populations now on the steeper slopes and similar hill edge woods.
This prolonged water-logging is going to affect plant growth too!

Colin and Elizabeth said...

Great post. Looking at the pellet picture at full size it looks like feathers in there?? The Buzzard certainly enjoyed his meal, as you say its life.