Before you start:
There can be few things as thrilling as finding that a pair of owls are using a nestbox you have put up. Before you go out and buy one, here are a few points that need considering — as well as some encouragement!
First: do tawnies live nearby?
It's an obvious question, but there's no point putting up a nestbox if there are no Tawny Owls in your area. Unlike Barn Owls, tawnies don't move around very much -- maybe a few kilometres during their lives, usually in their first year.
You'll know if there are tawnies around because you'll hear them -- the sharp kewick of the female and the hoot of the male. They're usually heard between 9 pm and dawn, and the main calling times are the nesting season from mid-March to fledging in mid- to end May, and in early autumn -- the beginning of September can see a surge in tawny bawling.
If there is no evidence of a local pair but people living within 2-4 miles of you say they hear tawnies it might be worth putting up a box. Every autumn the current crop of youngsters is evicted from the parents' territory and the young males have to move away to establish their own. The evidence is that they will move up to about this distance to find a vacant patch. Remember though that your immediate vicinity might be owlless for good reason as whether they can survive in an area depends on food supply far more than on a suitable nest site. Also, tawnies prefer areas with a mix of woodland (or good tree belts) and open fields as the best hunting is at the edges of the fields, with the trees providing places to perch while they watch for prey and, in spring, nest sites. Treeless areas are not good for tawnies.
Do tawnies use nestboxes?
Yes. If you hear a pair in or near your garden there's a very good chance they'll use a nestbox. Researchers put up dozens, sometimes over 100, nestboxes in areas they are studying and occupancy rates are always high (like 75% plus). Also, once a female has used a nestbox she's likely to use it again in preference to whatever natural site she was using before. Tawny Owl territories are about 0.75 to 1 square kilometre in extent, and if a nestbox is put up anywhere in a territory these observant birds are almost certain to find and investigate it.
Are Tawny Owls helped by nestboxes?
In our experience, most definitely! As I bang on elsewhere on the website, tawnies are threatened by woodland management practices -- and tree surgery generally -- which deprive them of the tree cavity (hole) nesting sites that are the safest place to rear a brood. Many are now forced to use the stick nests made by other species, such as crows. In such nests the young owls are at great risk of falling, with often fatal results.
She took a year and a half to think about it, but one day we found our favourite mother tawny in a nestbox we'd put up near the crows' nests she'd been using for some years.
If we put up a nestbox are we likely to see the owls?
Yes, especially with the simple box design described in the next pages. Putting one up is the best way to see these retiring creatures. The nestbox will be occupied by the mother from around 20 March. The chicks hatch 28 days later and fledge another 28 to 35 days after that. The father brings his mate food (at night of course!) while she is brooding and feeds the whole family after the chicks have hatched. If you have a nestbox with a low, central entry door you will see mother and chicks during the day. About 10 days after the first chick hatches the mother leaves the nest permanently and takes up a post in a nearby tree (up to 50 yards off). The father then brings his catches to her there and she takes them on to the nestbox. She will be there during the day too as she is guarding the nest. When the first chick fledges it will stay nearby, close to the mother, for some days until the last chick has fledged, when the parents may take them off nearer to where they hunt. During the time the fledged chicks are near the nestbox you will have marvellous views as they don't seem to mind people approaching then.
Right: What you may see if you're lucky! These pics were taken soon after dawn with a camcorder. The owl is the mother of my box tester, who appears on later pages. This little owl fell out of the crow's nest her mother was using in 2005 and is lucky to be alive.
How will we know if the nestbox is being used?
. . . apart from at nesting time, of course. The answer is that you may not know until you suddenly hear a female calling around mid-March, when she's in the box and about to lay. I've found that parent tawnies are very clean around the nest and tend not to leave traces like droppings or pellets. The only thing you may find out of nesting season is a dropped feather. Tawnies definitely do visit nest boxes at other times of the year though.
What you will hear when a female starts on the the nest is umistakable. Basically, after about 9 pm, many brooding females call out periodically to their mate: kewick ... kewick ... kewick. The male comes in about every hour between then and dawn, and his visits can be the occasion for one helluvanowlhullaballoo. The female greets him with joyful cries, and sometimes on hearing his approach (announced by hoots) she'll leave the nest and cavort with him in the branches — to the accompaniment of incredible noises from both. Not every pair behaves like this, but you are likely to hear both birds when the male makes his regular visits. In March and April, a female regularly heard caling at night from the same location is an almost certain indication that she's nesting.
The chicks may or may not be heard while they're in the nestbox, but once they've fledged you may hear them setting up a continuous hoarse squeaking from early dusk. Parents reduce their calling considerably when nesting's over.
April 2008: two chicks and an egg. After missing out in 2007, the female raised another brood this spring.
Are Tawny Owls disturbed by human actvities?
Hmm, yes. But like many birds (Woodpigeons in London!) they can become very accustomed to a human presence. If you come across one in a wood it usually makes off before you've got within 50 yards. There are two factors here. First, a pair that visit your property as part of their territory are quite likely to know you better than you know them. Second, like many breeding birds, a female will stay on the nest until she feels a threat is dire and imminent. So if you are careful about how you approach a nestbox she'll stay put, and in a week or two she should be quite relaxed about visits. The most she may do is duck her head to hide from view. If she flies off you should stop all visits for a couple of days before trying again, cautiously.
The male may be a different matter. He's not going to be sitting on the nest with a chance to learn that you are no threat. So there's a possibilty that if you stand around at dusk or after nightfall hoping to see him come in with food he'll beat a retreat. Again, leave and don't visit for a couple of nights. This was the situation with my nestbox owls last year. The female was perfectly happy about me turning up, sometimes quite noisily, and being around all night. But the visiting male would glare fiercely at the tent I was using as a hide -- he knew very well someone was in it. Once when I made a sudden movement he flew off and didn't return that night . . . or the first part of the next. Obviously I had to leave, but by the time I resumed a couple of nights later he'd got over his shock. He still glared at me every time he came in though!
To give an idea: in 2004, when we first observed her on an open nest, the female would fly off as we came down the woodland path. Later that season she stayed put. In 2006, in the nestbox, she sat tight even when I put up microphone booms one night, and after her first chick had fledged she allowed me to move around directly beneath her filming for 40 minutes. She stayed there, looking perfectly relaxed, when a neighbour unexpectedly came along the path and joined me.
2006: The female was relaxed about my presence, but the male would stare fiercely at the tent every time he turned up. The mother's head and tail are just visible in the box - she's facing left.
After a chick has fledged the mother allows me to film her -- and she's looking proudly at the chick, not me.
In 2006 two owls nested in a pine near the house. This is a busy area (the left pic shows the garage and attached shed), with cars coming and going and people walking around, including to the chicken run beneath the nest tree (right). The owls roost at the bottom of the drive and probably know us all well.
Like our other pair, this couple didn't breed again until 2008, when they raised two youngsters in another nest site near the house.
A good solution to the problem of disturbing the owls is to observe from a distance with binoculars. It's actually the best way as binos allow you to get a better angle over the bottom of the door, so you see more, especially if the female's trying to hide by ducking her head!
When's the best time to put a nestbox up?
Any time is ok if that's the best time for you. Most people would say September to October is best for the owls as that's when they're hustling the old children on and starting to think about next year's business. I'd agree, though I've put mine up in November and early December, which is getting late. Tawny females seem to like checking out a nest site for some time before they lay. On the other hand I've seen a report of a tawny nestbox being occupied 24 hours after it was put up -- presumably in the spring! By mid-March you've really missed the boat for the year. So, let's say any time over the summer with September best and your chances of having an occupied box next spring declining steadily thereafter.
We have pets/children -- could a pair of breeding Tawny Owls nearby be dangerous?
The short answer is definitely yes, and you should be very wary about approaching an occupied nest or nestbox. The most certain way of inviting an attack is to go near or handle a chick/fledgling on the ground. If either of the parents is around — especially the mother — you really will almost invite an attack. More reports of attacks by owls, including tawnies, are coming in as time goes by. For the effects of an attack, see my News 2008 page. This was a mild one! I've had the same done to me.
Tawny owls also detest dogs — it's probably something to do with their uneasy relationship with foxes, which eat their chicks — and may attack them also. On YouTube there's a video of a Great Horned Owl swooping on a dog that's out for a walk. Here's the clip.
So take care. Owls fly in to the attack with their legs out front and claws extended. A tawny's claws are sharp as a cat's and about twice as long. Even more dangerous, they make straight for the head, and if you happen to be facing the owl that could be bad news. So best not to let children approach a nestbox or other nesting site unaccompanied.
However, if your owls live or roost or are active near your house, they will almost certainly be more tolerant of people than owls in more secluded areas, and as long as you treat them with respect such an attack is unlikely.
I don't want to suggest for a moment that tawnies are naturally aggressive, or on the lookout for a fight! By and large they're rather timid, soppy birds with lovely temperaments. Lke so many animals, they will only attack if they feel threatened.
powered by owls
A nestbox in use in the 15-acre grounds of The Hawk Conservancy Trust near Andover, Hampshire, here in the UK. My thanks to John Baker © for kind permission to use this photo. Click on the pic for the original photo (for design reasons it's been reversed here).