Tuesday, June 25, 2019

Boxing News

A few weeks ago I mentioned how Andy’s contacts had invited him along to see progress in two nest boxes installed at their home. At that time a pair of Kestrels occupied a box located on a building and a pair of Barn Owls occupied a box not too far away in an open fronted barn. By using a nest box camera it was possible to see that the Kestrels had laid 5 eggs and the owls had 8 eggs. 

Barn Owl

Armed with our Barn Owl Schedule One Licence and ringing gear we went along on Monday in the hope of catching the youngsters at an appropriate age to fit their rings. Our general ringing licence covers the ringing of Kestrels but extra protection afforded to Barn Owls requires stricter rules.

Andy went up to the Barn Owl box and brought down 3 chicks. One small one proved too tiny for a “G” ring while the other two were about right, each with well-developed legs and feet. 

Barn Owl Box

Barn Owl - too small for a ring 

Barn Owl

Barn Owls begin incubation as soon as the first egg is laid and lay additional eggs over a period of around 8-21 days. After 31-32 days' incubation the eggs hatch every 2-3 days, usually in the order they were laid. This is termed “asynchronous” hatching. The age difference between the oldest and youngest nestling can be as much as three weeks. This age variation reduces the peak in food demand and spreads it over a longer period. The female does all the incubation and the male provides all the food until the young are around 3 weeks old. 

Research shows that Barn Owls regularly let their nest mates know whether they plan to compete for an incoming meal or not. The delivery of usually a rodent of some sort is fed only to a single offspring at a time, chicks queue up based on their hunger level. This approach prevents arguments (in the form of beak stabbing and stealing) from breaking out when the food arrives, thus ensuring the maximum survival of the brood. 

It will be several more weeks before our two young owls are old enough to leave the box and fend for themselves. Meanwhile the camera should let us know how they all develop, including the runt. 

Meanwhile, four juvenile Kestrels were of an ideal size and age to take an “E” ring. From their size we estimated they should fledge in about a week or ten days. 

Kestrel  

Kestrel 

We also took advantage of a brood of five Barn Swallows that were at the ideal age for ringing. 

Swallow 

Swallow nest

All in all, a successful and productive few hours.

There's more news, views and photographs soon by logging in to Another Bird Blog.

Linking today with Anni's Birding and World Bird Wednesday.

11 comments:

David M. Gascoigne, said...

Good morning Phil: I have never had the pleasure of an owl banding session, so you are one up on me there, but I have participated in the banding of adult raptors as large as Red-tailed Hawks and Northern Goshawks, and that can be quite an adventure. Bravo to you guys for a job well done with these birds. It always seems remarkable with Barn Owls that the different youngsters often survive together despite vast differences in size, and siblicide is not common practice. This presupposes a good rodent year, of course, and efficient adults to deliver enough food. I am sure that I am not the first to draw the comparison between a Barn Owl family and a human family when the kids are lined up for a photograph. I am a great admirer of the British bird photographer, Eric Hosking, and some of the early work he produced of Barn Owls is nothing short of spectacular; in fact, revealing behaviours never previously recorded or even known. Your morning's work made for a great read, Phil. Thanks to you and Andy.

Natalia said...

Oh wow, I have never seen baby owls before, so cute!:)

eileeninmd said...

Wow, love the cute baby Barn Owl. That is cool to be there for the banding. Cute captures of the owls and the swallows. Wishing you a happy day!

Tanza Erlambang said...

barn owl chicks so cute....
hope, you success in study of birds

Angie said...

Phil - loved the last two posts, given the presence of Owls in both of them. And young ones to boot. So glad you are qualified to do this ringing and can bring us these fabulous photos of the owls, kestrels and so many other fine birds!

italiafinlandia said...

Your chicks are irresistible!

Wally Jones said...

Your post made a very nice read with morning coffee. Kudos for doing such important work!

I even learned about Barn Owl parenting strategy. Interesting stuff!

Azka Kamil said...

nice article my friend..
please visit my blog too

Lowcarb team member said...

So interesting to see your photographs and also learn a little about the Barn Owls. I'm so pleased that you were able to ring some of them and it should be fascinating to see them on camera over the coming weeks.

All the best Jan

Anni said...

That is so exciting! And thrilling to see this all come about. Fantastic photos and fabulous conversation explaining it all. Thanks for linking up with us birders this week.

Rhodesia said...

Well done it sounds like a very successful day. I always thought that Barn owls were beautiful. I have to say the babies are a bit like the ugly duckling but one day they will be beautiful. Have a good week Diane

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