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Building A Bird Hide Screen At The Trap Grounds


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Bird hides are structures that people hide in, so they can see birds without scaring them away.

A bird hide usually looks rather like a garden shed with a narrow horizontal window at eye level and some sort of camouflage to blend into the natural surroundings. Often they are close to ponds and wetlands, because those areas attract more interesting birds. The whole structure isn't really required to watch birds, and on a nature reserve in a town, a roof and seats would make it rather a tempting a place for teenagers to hang around.

So we were approached to create a much simpler structure at the Trap Grounds: a bird hide screen, sometimes called a bird watching screen or bird blind. The basic plan was to erect a screen, between a path and a pond, which would have viewing slots in it. It would need to be long enough to hide the section of the path that went close to the pond, and it would have to go around a platform created for easy wheelchair access.

Planning and Designing

I consulted one or two people who occasionally used bird hides. I wasn't so interested in serious bird watchers' requirements, since they tend to go further afield and most of the users would be casual visitors or passers-by. They told me about some of the design features that they'd noticed in bird hides in tourist attractions such as nature reserves, country parks and the grounds of stately homes. As another part of the research I also looked at some websites for inspiration and, after discussions with a couple of people from the local group, a few ideas came to mind.

There would need to be slots at different heights for children and for people in wheelchairs or seated. The slots should also provide somewhere steady to rest binoculars. It would have to be difficult for people to hide behind. We wouldn't want it so close to the path that people walking past alone at dusk would be nervous and fearful of attackers jumping out. It would be all too easy to make the path seem a lot darker and more frightening if we put up screens close to it.

We also wondered what sort of material would be good for the screening. We discovered that hand-made traditional screening from local sources was prohibitively expensive. Buying imported screening from the Far East was hardly in the spirit of nature conservation, both in terms of using non-native materials and the carbon footprint of shipping low-grade timber half-way round the world. We also considered whether our volunteers could make the screens from materials harvested on site. That sounded interesting, but potentially too labour-intensive, even for us! In the end we settled on buying brushwood screening from a garden supplier. It would be UK sourced, but probably processed mechanically in a big factory so that it wouldn't be so expensive. Ready-made panels were expensive, but rolls of screening were better value, though this would mean we'd have to add battens to give the screen some rigidity. That wasn't a problem really because we'd be able to make the battens fit the gap between the posts exactly.


Types of bird hide screening panels


I visited the site and discussed ideas for construction. We'd have to make it simple to construct in no more than two days of tasks. We sometimes do projects that take more than one day, but it's usually best if they don't go on so long that people get bored of doing the same thing. We like doing a variety of tasks and people might not want to come back time and time again to do the same project.


Post for bird screening


I also tried to simplify construction as much as possible. This usually means nails rather than screws or bolts, not too many different sizes and shapes of timber, and timber that is pre-sawn and pre-treated as much as possible.

We discussed whether it would be a continuous stretch of screen or several separate screens at oblique angles. A continuous stretch would be better for hiding from the birds and would be more difficult for people to get behind, but the down-side was that it might be blown over by the wind. I suggested that if the vertical posts were strutted on at least one side they would probably be wind-proof. The struts would be nailed on so they would offer some support in tension as well as compression.

The vertical posts could be dug-in in much the same way as we do for fence straining posts: straight deep holes with the earth tamped back down very firmly. We have a lot of experience doing fencing in the group and so it's always good if you can use skills from one project on other projects as well. Hole-digging is a very transferable skill!

Once I had a draft design, I sent it to one of the members of the local group, the Friends of the Trap Grounds. He had a number of modifications, and most importantly he'd actually measured the site, so I could update the design to include more accurate dimensions. As usual the dimensions were also dictated by the sizes that the materials were available in. I simplified the design a bit because I wanted to reduce the number of post holes that would be required. Digging the post holes would be the most significant part of the day. The site had been used as a rubbish tip and there could be large lumps of steel or reinforced concrete below our feet.


Top view of panels attached to posts


With the final design signed off, it was just a case of working out what parts of the project we'd do each day, ordering the materials and bringing the relevant tools.

The First Day

At the time of planning the project we had a van which could take long posts inside, so we agreed to help move the materials. But when it came to the day of the project we'd actually got a new van with a bulkhead between the tools and the people. A week or two later we'd get roof bars fitted, but at the time of construction it was necessary to borrow a car with roof bars to move the long posts. This added an extra bit of organising on the day, but it was better than my fall-back plan of asking people to walk nearly 1km along a path carrying the 3.6m posts. That wouldn't have made me very popular!


Getting started on the post holes


When it came to digging post holes we had no idea whether it would be soil or impenetrable concrete and metal rubbish under foot. I thought it was just possible we'd have to drive in some posts because the ground would be soft and muddy near the pond. In fact, there was about 0.8m of mainly soft rubble including a lot of bricks, some wire, concrete, rubber tyres and a toilet basin. We punched through that with a crowbar and under the rubble we found quite soft mud. This meant our holes were nearly deep enough, but we'd have to drive the posts into the mud, because you can't dig any further if the hole keeps filling with water.


Using a bar to dig through the rubble


For the first time in my experience we discovered that we could use a post driver slightly above head height, provided you could reach the bottom of the handles and you didn't need much force. We made extra sure we were wearing helmets and going fairly gently because there was more risk of banging your head than normal. Heavy tools are dangerous at the best of times but this posed additional hazards, not just to us but to curious passers-by. Nevertheless the posts were driven in quite easily because of the soft ground.


Reaching water level




Tamping back the soil


The posts ended up pretty solid in the end, but the struts would finish the job. They would be just like struts on straining posts and since we do a lot of fencing, it didn't take us long to do those.


Cutting a slot for the point of a strut


As with lots of other projects, you never quite know what will happen until you start construction; often you have to make small changes, because you encounter a problem or because you spot ways to improve on the plans. Someone suggested we re-use the same stob for two struts. In all my planning that had never occurred to me, but it helped to speed up the process considerably.


Starting to take shape


By the end of the first day we'd got more than half the verticals dug and driven in and strutted. Provided there wasn't too much vandalism we'd be able to get the rest of the verticals in next time and also attach the screening to finish the job. We'd be able to start on with the screening while there were still holes to be dug which would mean that we'd be able to keep everyone busy and do more than one part of the project at a time.


End of the first day


The Second Day

On the second day, we got started on digging in the remaining posts. Some of these post holes were quite tricky because there was a lot of rubber and wire. This is hard to dig through and almost impossible to drive a post through because it just bounces! Eventually we got there though. We also got our brushwood screening and unwrapped it to make sure it was the right size. It comes in 2m by 4m lengths and we decided we'd use it doubled-up because it wasn't quite as opaque as we'd hoped.


Brushwood screening


Then we started attaching the battens to the posts. There were to be 4 battens per section, which we hoped would be strong enough. Battens like these are very prone to splitting, so we had to drill pilot holes for all the nails.


Battens attached


Once the rear battens were attached we unrolled some of the screen and attached the front battens in place, taking care to grip it at the right level.


Attaching the screening


The aim was to sandwich the screen between the two battens so that it was firmly gripped. This meant we had to be careful not to hit the front nail into exactly in the same place of the nail holding the rear batten. Since we were drilling pilot holes we could use nice long nails that would go through two battens and into the post behind, providing we got the angle right.


Battens sandwiching the brush wood screen


The battens went on at different heights on the different sections so that slots could be made for viewing the birds by just cutting away the screening between two sets of battens. The battens were also nailed onto each other so they didn't get loose between posts. Whenever we nailed them, we made sure we braced it from behind. We took care to use a block of wood for bracing from behind rather than hands, feet or shoulders. Otherwise a nasty injury would have been possible if the nails were too long and had come all the way through.


Finishing off


At the end of the day there was a bit of a hurry to get it finished, but we got all the sections of the screen up in time, so the structural part of the project was completed. We didn't cut the slots out because we wanted to do it when there was time to think about how long they should be.

We couldn't take a photo of the finished result because it was getting too dark at the end of the day. In fact, the last few nails were knocked-in in the dark, which is far from ideal, but perhaps to be expected when you do a big project in November. We'll be coming back another time so we can make some finishing touches to it then.

Of course, the real test will be whether it's good for watching birds, and we await reports from the locals on this.

Chris Skepper (OCV Task Programmer)

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