Reflections: 11th May 2020 - Flying a kite

Red kite over Wareham Common 

Now that I do not get out as much as I used to I have taken to closely following the tweeted sightings of other nature enthusiasts in Dorset; indeed I am now in my fourth year of analysing what others see. Since I started the process in January 2017 I have never seen anything quite like yesterday's sightings! There were staggering 32 tweets reporting red kites over Dorset, almost all from coastal locations but, more significantly, these reports included 63 over Westbourne, Bournemouth, 79 over Bridport and an amazing 112 over West Bexington near Abbotsbury. 

Some of the 32 reports will obviously be of the same birds seen by different observers but the three locations I have mentioned I chose not only because of the number of birds seen but because they are spaced out and not likely to be duplicated sightings. These will not be actual totals for the whole day from each of these three locations but totals for the period of time someone was watching so the real totals will be higher than the 254 that were counted. There were birds coming at other coastal locations too so one can only wonder just how many passed through the county in one day - possibly 300?

Whilst the numbers yesterday were truly exceptional this spring has seen a continual movement of incoming migrant birds that started back in week 12 in mid-March. Since then there have been 258 tweets reporting red kites, usually in small numbers of between 1 and 3 birds so if the average per tweet up until yesterday was 2 then that is potentially another 500 birds this spring on top of yesterdays guess of 300. This is only the birds seen and recorded, so is the real figure approaching a 1,000? We will never know for sure but one thing is certain, it is a lot! The RSPB estimate the UK population to be around 1,800 breeding pairs so if my guesstimate of about 1,000 passing over Dorset this spring is anywhere near corect that is a quarter of the UK population!

This raises many questions and I am sure the answers will become clearer when the BTO and the RSPB have access to data from across the country. I ask myself why is this year is so different to previous years I have monitored? Last year I detected 92 tweeted sightings between mid-March and the end of May and in 2018 103, possibly 'just' 150-200 birds each year. In 2017 there were only 47 tweets or less than 100 birds seen. The annual trend does seem to be upwards but then the UK population is increasing having been almost extinct some forty years ago.

One also has to ask why yesterday was so exceptional? There was a strong north-easterly wind yesterday and these birds were flying directly into it; there have been far better conditions to make a journey of this nature. 

The most significant question in my mind is are these returning migrant birds or are they new birds moving northwards because of influences elsewhere on the continent? It may seem obvious at first glance that these are returning birds but it was a fairly mild winter across the UK compared to other years so why would so many more have decided to go south last winter? If many more did decide to migrate south then why was there no corresponding evidence of an outward movement during the autumn and winter? If they are new birds then what is the stimulus that has triggered this movement and where are they all going? 

I hope we get the answers to these questions one day.


Popular posts from this blog

Two-banded Longhorn Beetle: how boring | Nature Notes from Dorset

Reflections: 19th February 2020 - Under the weather!