Friday, November 10, 2006

Well, tonight I have mostly been under bridges….. Well, not quite true…. It was last night, and a lot of the time we were driving between bridges. One of my colleagues (Alex, find him at Birdwatch Ireland) is monitoring the Dipper (Cinclus cinclus), population, (a small bird which hunts underwater for invertebrates such as stonefly and mayfly larvae) which means that he finds the nests and watches to see how successful each nest is. I have helped him a little with this during the past year.

If we are absolutely honest here, Alex allows me to help him. He gets an extra hand, particularly in the way of Health and Safety, no-one likes to be climbing down riverbanks and struggling through fast running rivers under a narrow bridge, at night, without someone else with a mobile phone handy, or a big stick handy. Sometimes it is very helpful if someone has a big stick that you can grab. Behave, I’ve been in that situation several times in bog-land in Shetland and if I had to spend an evening wondering what would have happened and how deep the bog was (and I’m 5 foot 10 to my mouth and nose), I probably wouldn’t sleep as I do. To be even more honest, ringing the emergency services to save a guy in this kind of situation may be completely pointless, because if I can remember which bridge out of 15 or 20 we are at, and we are at the right bridge (sometimes we get down the road and realise that we were at the wrong one), then there is still the problem of getting the emergency services to the right bridge as well. Hmm, will have to think about that one… could be me in the river….

At this time of the year he goes to all the bridges that they roost under at night, and checks to see how they are doing. Using individually numbered metal rings fitted to the bird’s legs, we can find out several important things. How many are surviving, how many chicks survive, where they are from, where they roost? This information can then be used to determine factors which are affecting them. The greater understanding of a species increases our ability to help to conserve them.




Tonight we visited approximately 15 bridges, some of which were unsuitable, some of which were suitable and not in use. 3 of the bridges were in use and 2 birds were captured and ringed. These birds had not previously been ringed. We able to age both of them, using clues from the feathers and the eye colour. One was an adult, and one bird which had been born this year. The younger bird was a nice surprise as most of the chicks in this area will have been ringed at the nest, so this bird represents a nest which had been missed which we can still continue to monitor. Hopefully we shall meet this bird again in coming years.

Both of the birds captured last night were of particular interest to me, having only previously ringed chicks of this species in the nest. The bird is approximately the size of a blackbird, incredibly short-winged and powerful, with an amazingly strong grip. These attributes allow the bird to both swim underwater and grip the rocky substrate of the fast flowing streams which it prefers. This is the favoured habitat for the invertebrates on which it feeds; oxygen rich clear water. Fast flowing streams that narrow when they are contained by the limits of a bridge are not always the favoured habitat of the guy in none-gripping wellies or waders, trying to monitor them, it can be dodgy, and shouldn’t be attempted by children at home, or adults without a big stick for balance and depth measuring, but mostly, and I’ll repeat it... balance. I nearly went down 4 or 5 times last night, and the current wasn’t strong, that was just sediment change from firm to soft, shallow to suddenly quite deep, or one big stone.

The bridges that we visit include featureless concrete structures, modern designs and also ancient and rough featured works of wonder. Some of the latter span gullies and cracks in deep ancient rock formations, (and I hope to provide photographs of these at another date), whilst others may be bland and have little headroom and be a few feet deep.



The adjacent counties to Offaly are separated by river and stream boundaries. Ireland is wet, it has many streams, and the countryside is dotted with bridges. I read somewhere that Ireland has the greatest length of road per head of population in Europe. This is because the countryside still contains a large proportion of the population, and they all have a road leading to their house. A lot of roads, plus a lot of rivers… equals a lot of bridges. I’m hoping to be very busy this winter and see a lot of Dippers.

I may see fewer Dippers than I wish this winter, because the number of people that can attend an operation like this needs to be kept to the bare minimum for disturbance purposes. All of these things are factored into this kind of monitoring. There are number of fieldworkers who need this kind of experience and I will take my place alongside other novices to work with experts in this field. If anyone is reading this and intends enjoying this experience, which I have shared with you, please do not attempt this alone. I am sharing this with you, so that you can enjoy it by proxy. Do not, I beg you, disturb birds for any reason at their breeding grounds or roosts without expert supervision, it cannot help them at all. We at Birdwatch Ireland and also the Royal Society for the Protection of Birds and the British Trust for Ornithology and others worldwide only interfere with birds at these important sites and times with the fullest and most recent advice from current research. Disturbance of sites is always well considered and not conducted unless the benefit of the species is paramount.

My Gosh! I never thought that I’d ever do one of those “terms and conditions apply” things in a blog. I just recently found that my blog is accessible in the first page of “Google” and “Yahoo”, so I’m being especially careful, I guess. But seriously folks, feed them in your garden, put up boxes, don’t go under the bridges at night without an expert, you know it all makes sense.

Slainté,

Davy

4 Comments:

Blogger simon said...

Dave.. what a great entry.. looks fantastic work and difficult too. 9 water bridges etc)

BTW the previous comment should be deleted.. this "make 900 a month" is bullshit....

i have seen it appear on other blogs...

10:08 PM  
Blogger Maalie said...

Nice entry! Hey, you never used to say things like "My gosh" when you were in Shetland! I've done some of that Dipper work in Shetland - exciting but exhausting after a night under bridges!

I agree with Simon - you can prevent that Spam by activating the feature in which the person making the comment has to type in a code that appears. I'll email you.

11:50 PM  
Blogger Maalie said...

Sorry, meant I did it in Wales, not in Shetland!

11:51 PM  
Anonymous Anonymous said...

Incriminatinbg evidence of Maalie on my own site...

1:38 AM  

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