Some nice introductions!

There are some bird species which were introduced into the UK that have become naturalised, which somehow fill a niche without major problems and become a 'nice' accepted addition to our avifauna. But before I go further lets define introduced species. They are the ones we never had in the first place (not natural), so if and when their populations die out and we want them back we reintroduce them. Case-in-point are pheasants (and Red-legged Partridges), were introduced and then are reintroduced every year at numerous shoots throughout the UK. So why is the term reintroduced used for birds like Red Kite, Osprey, White-tailed Eagle, Cirl Bunting (also falconers gave us Goshawk back on unofficial releases) etc, surely they were never introduced in the first place? They were once part of our natural native avifauna, so they are not reintroduced when brought back, merely re-established or trans-located from suitable donor sites. [Glad to say the Devon Bird Atlas 2007-2013 available here, at least referred to Red Kite and Cirl Bunting (in a Cornwall context) as re-established].

So back to my starting point. There are some 'nice' real introductions or reintroductions. For me at least two, Little Owl and Mandarin Duck (remember Ruddy Duck, but they didn't fit in!). Sadly I hardly see any Little Owls now, as many of their former haunts in Devon are unoccupied, e.g. I remember three territories around Prawle now vacant. Something has affected their breeding ecology; just look at the BTOs abundance change map for 1968-72 vs 2008-11 here, quite striking isn't it? A large decline in the west of its former UK range. Yet Mandarin seems to be doing well , particularly where I live. When taking a local walk by the river they add a welcome splash of colour. But how many are there on my local river now? In 2012 I chanced upon a private residence, where the lady owner had started winter feeding the local Mallards and Muscovy Ducks (another introduced species here!). But what it was also attracting was 'wild' free-flying Mandarins from up and down the river. In 2012 we had a peak count of 48 there, pretty good. But in 2013 we had a peak count of 88 on 16/01/2013! We didn't quite hit those levels in 2014 just high 60s. But in 2015 again we hit 88 on 06/02/2015. 2016 was marginally lower with 80 on 04/03/201. I expect there's actually over 100 as there's a lot of coming and going and probably not all the same birds are seen on subsequent days. I.e. there is at least one uniquely plumaged 'pale' male that was not present during one of the 88 counts. In a Devon context these numbers are very high! Come spring and they spread out along the river favoring the upper reaches and some tributaries, where if you're lucky you see family parties of ducklings later on. This winter I've not seen so many, perhaps its due to a new kayak launch site that started near the feeding site!

A Mandarin melee! River Dart 20/01/2013

Wish this was my birdtable!
The handsome drake Mandarin a worthy introduction!!

1 comment:

  1. Good point... Keep waiting for the next post. Great stuff.