Friday, 18 May 2018

A Worrying Spring

Am pretty sure that any and every birder who regularly watches a coastal area or migration hot spot will agree with me when I say spring 2018 has been absolutely dire. Numbers and the variety of species has been dismal, with only two single days here when the bushes could have been described as being 'busy'. The skies have been far quieter than usual too, with very few days when visible migration actually got going.

Now this on it's own could mean nothing. In my opinion you simply cannot accurately monitor population numbers of migrant birds species on 'how many you see passing through the coast'. There are just too many variable factors when it comes to migration and spring falls, with the weather being the greatest. If the sky is blue and there's a gentle south westerly wind giving migrants a helping hand as they fly north over the English Channel, then there's absolutely no need for them to land on the first bit of coast they see. Also, if they've had a good trip up from South Africa to Southern Europe, then they'll have more reserves than if they'd had a bad trip up, so again, less likely to drop in on the south coast of UK. Food availability can be a major factor too, if they've had plenty of chances to feed up during their journey northwards then they will again have more reserves to fly further without the need to stop. So so many variable factors that can dictate how many migrant birds we see on the south coast during spring.

What is really worrying though is the comments and stats I'm seeing all over the internet regarding the numbers of many of our migrant birds on their breeding grounds. Let's take a quick look at BTO BirdTrack, the best platform to monitor and compare UK bird population data through citizen science. This is the current graph for House Martin...



And Grasshopper Warbler...



The magnitude of comments that I've read on Twitter and various blogs regarding poor numbers of some of our migrant species on breeding sites have been particularly focused on Swift, Swallow, Willow Warbler, Sedge Warbler and Common Whitethroat. Also some of the scarcer species seem to be in a bad way too, like Wood Warbler and Nightingale.

A week or so ago I was pretty certain spring was just running late this year, but it's the 18th of May and I'm now thinking this isn't the case. I really do fear something catastrophic may have happened, either during the spring migration or on their wintering grounds.

I'd be very interested to know what your eyes/ears/stats/mist nets are telling you, drop me an email or leave a comment if you get the chance.

12 comments:

  1. Certainly my worst spring I can ever recall, I even missed the fall! in previous years if I missed one fall I would be certain of catching up with most of the species on another day - not this year. I've only manged to notch up Willow Warbler at Berry Head on 4 dates this spring!

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  2. This sadly gives numbers to what we have all experienced this year however we have seen a bird in the back garden at least six times this year (Great Tit, Blue Tit, Wren and Blackbird) which is more than the last ten years combined if you exclude Herring gulls and Jackdaws from the count.

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  3. Similar picture at West Bex/Cogden Steve and although mainly an autumn migrant here, we haven't recorded a single Yellow Wag this spring. That said, we do seem to have most of our breeding Whitethroats in and LWTs were early...

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    1. Great news about the Whitethroats and Lesser Whitethroats Mike, I think Lesser Whites are actually on the increase around here - each year we seem to have an extra one or two singing males. Thanks for the comment.

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  4. I have been recording the dates of arrival of two species.Swallow and cuckoo since 1997.
    The swallows have arrived at the usual average date at the end of the first week in April.
    I have heard the cuckoo call for the first time in 7 years,so its good news from South Somerset!.

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    1. That's brilliant news! Thanks for sharing

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  5. I'm the guy with in-laws in Seaton. In our area of West Yorkshire cuckoo, pied fly, blackcap, sand martin, mipit doing great but curlew and swift numbers are low, and not a single wood warbler has been reported in the Strid Woods at Bolton Abbey, which is desperately sad - four or five singing males have been possible in the recent past

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    1. Hi mate! Great that those species are doing ok up where you are, but interesting that you mention Wood Warblers as being down in trouble - the Dartmoor population is in serious decline sadly. I guess they are on the fringe of the UK distribution though. See you soon

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  6. Steve,

    Do you (or we, as a wider birding community) know how the picture is elsewhere? Given our awful early spring weather, I wonder whether a lot of 'our' birds chose to stay in France instead. The recent reports of the decline in French farmland birds suggests there's plenty of available breeding territory.

    Is it possible to split the Birdtrack graphs to look at different areas of the country? I wonder whether the north of England and/or Scotland are experiencing similar issues to those of us on the south coast?

    On my weekly walks in the Midlands, I'm finding that Swift numbers are good in some areas (RSPB Middleton Lakes had dozens last weekend) and I'm seeing them overhead whilst travelling around, usually in groups of four or so. House Martins and Swallows moved through in decent numbers but seem more localised than usual now.

    Wood Warbler are doing very well in the Wyre Forest. If anything more numerous than recent years. I've been over there again this morning and heard them regularly throughout a four-hour walk. (I won't mention the 2 LSW I stumbled across - now that was a treat).

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    1. Hi Rob. Interestingly I had an email from Terry Coombes who lives in eastern France just before I read your comment, saying everything seems to be present in low numbers there as well - particularly Swallows. So good to hear Wood Warblers are doing well somewhere! Thanks for the comment, Steve.

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