The weather is hardly tropical yet but it's thawing in most parts of the country. Whether we've seen the end of snow and ice for a while is yet to be seen. What are the early indications of impacts on birds?
It's too early to tell, for sure, but it's fun trying to work it out from the evidence that we have at the moment. One of the problems in coming to any view at all is that there are at least three things happening to our birds: they are moving to new places because of the cold weather, they are behaving differently and they are dying. Added to which our behaviour is different too - we may spend more time at home and less at work because of travel problems and visit different places to record our birds for the same reasons. These factors could all affect bird reports and that's why I'd be cautious to draw any conclusions at all until the standardised, long-running, regular bird surveys come through over the next weeks and months - and into next year!
The monthly BTO/WWT/RSPB/JNCC Wetland Bird Survey counts are coming up. This survey counts waterfowl at thousands of sites across the UK every month. It will eventually show us whether birds have shifted their geographic ranges in reponse to the freeze - for example are the lapwing which are missing from my local patch in east Northants sitting at Chew Valley Lake in Somerset where I went birdwatching as a boy? Or at least have populations shifted from the north and east of the country to the south and west and maybe even into Ireland? But these data take a long time to come in and be analysed, it's a very big job, so don't hold your breath for definitive news!
At the end of the month the RSPB's Big Garden Birdwatch swings into operation with sometimes as many as 500,000 people recording the birds in their gardens for an hour on the same weekend. This survey has highlighted changes in common bird numbers in the past (eg the decline of the song thrush) and may give us a very interesting insight into how many common birds have fared. We aim to have a quick look at the data to come up with some provisional findings within days of the BGBW weekend.
In the summer the BTO/JNCC/RSPB Breeding Bird Survey will monitor the population levels of a wide range of our breeding birds and will tell us more definitively whether populations have been affected by the freezing temperatures and snow cover. But these analyses won't be available until the summer of 2011!
But what can we guess at the moment?
Here's a fun statisitic. Lots of people are talking about seeing redwings and fieldfares in their gardens and the bird identifier on the RSPB webpage experienced a 5-fold increase in traffic for these two species. Not a count of birds - but a strong indication that there are more of these birds coming into our gardens to escape the freeze. Does that mean that there are also more of them in the country - they arrive from Scandinavia in the autumn - or does it mean that they are dying off and struggling to find food? Or is there a bit of both happening?
Another place to go for real-time insights into bird numbers is Birdtrack - a BTO/RSPB/Birdwatch Ireland project mentioned several times before in this blog. Using the 'Maps and Reports' tab on the home page there is the ability to look at reporting rates of many individual species ona weekly basis. Reporting rates are simply the proportion of all bird lists that included the target species, so it gives a very rough handle on actual numbers but that's fine for these purposes - after all I'm only looking at the figures through curiosity and for fun!
One more caveat - the reporting rates can change retrospectively if people add more data - for example if you have a lot of bird counts from last weekend sitting in your notebook and enter them next weekend (and many others do the same) then that may alter last week's reporting rates.
However, there are early indications for some of our common species such as wren, long-tailed tit and goldcrest that their numbers (no - reporting rates!) have fallen a bit in the cold weather and that might mean that they are dying off in bigger than usual numbers. Look at the graphs and you might persuade yourself of the same for some other species too. I'd have some faith in the wren and long-tailed tit graphs because these are common and widespread species which are known to be affected by cold winters, don't make big movements in cold weather and are easily identifiable. I wonder what the BGBW will show us?
Bitterns and woodcock look as though they are being recorded more frequently than usual - I'd put this down to changes in behaviour caused by the icy weather.
And what about fieldfares and redwings? Their reporting rates have shot up in the cold weather as they flock into gardens and towns. But maybe you knew that already by looking out of the window!
Funny you mention fieldfares! We have acquired a resident fieldfare these past four days in our garden. The only problem is he is the Attila the Hun of fieldfares and is trying (and usually succeeding)to stop any other bird feeding in the garden.
We have fatballs, mealworms, apples, seeds, peanuts and water out and he is attacking anything that dares to try and feed.
Our usual blackbirds, various tits, robins, wood pigeons, even the woodpecker are being seen off by him. I saw a blackcap land yesterday and start on a half apple but he was soon seen off by the fieldfare.
Any suggestions?
Hi Mark,Leicester Lass afraid all Fieldfares are aggressive,suspect those that come into gardens are very hungry and as long as only one or small numbers at least can only eat a relative small amount but understand it is annoying to see them harass other birds,ours particularly dislikes Starlings.Blackcaps tend to be quite aggressive as well for their size.Will be interesting after the bad weather has gone Mark but suspect all bird lovers feeding them will have minimised the deaths that otherwise may have happened.Lots of food must be fed at the moment and interesting the only shortage in our local Tesco was bird food because so many people bought extra.
'we had two fieldfares on Sunday morning along the bottom of the privot. Haven't seen them since hopefully gone back into countryside now that thaw occurring.
OH gave me a talking to earlier and was waving BTO Bird Study mags at me which show how badly Warblers Goldcrest and wrens etc were devastated with the snows last February. The lecture from him started because he discovered me saying on one your previous blogs,'C'mon its only been 3 week....... Apparently he can't believe my audacity or ignorance. I said you forgave or disregarded, my ignorance so, hopefully, he will soon too - lol.
Hi Susan yes easy to get it in the neck from OH but soon passes,think bad weather later in winter has much worse affect on all wildlife than it would now as their reserves are lower.
Leicester Lass, Sooty, Susan - lots of fieldfares and redwings in gardens. And there seem to be lots of blackcaps too. I suspect that some species' population levels will have been affected by this freeze - but we'll see. I do think that the BGBW results will be fascinating this year.
Susan - audacity is appreciated here! Your comments are very welcome.
Yes, we've got similar 'problems' with fieldfares - now 3 in the front and 3 in the back! I think the best we can do is to tie the apples in trees or on fences/ arches etc, then scatter seed (sunflower hearts great) and suet pellets over the rest of the available ground, so that they are separated to a certain extent. I've noticed redwing will take other foods besides apple, whereas fieldfares are only taking the fruit.
Mark. can you answer a question I can't find the answer to elsewhere. As well as the fieldfare etc this weather has brought in a lot of blackbird (15+ in garden at present) presumably also european. Why are they all males. Do the females go further south. Bob
Hi Mark even think RSPB feeding sprats to the Bitterns at Ham Wall or at least putting some down where they hope the Bitterns find them.Think that area had 7 breeding pairs last year,they seem to be increasing in numbers over the country very well.We now seem to have at least 6 sites within hours drive where they are regularly seen.
Saw my 1st Fieldfare over 25 years ago on the garden fence: had to find a 'Bird Book' to identify it for the children, as they thought it was just a funny looking Thrush. You could say that was the beginning of my interest in birds, as since then I have noticed them more, (birds in general, that is) especially if I couldnt identify them right away. Now this week we have had a Fieldfare in the garden again, after all this time, & reading all the Forums & Posts on this site, so have many other people. Extremes of weather do change the habits of the wildlife, & at least in this case it gives us the chance to admire those we don't usually get a chance to see up close.