A tale of the unexpected

There’s nothing up my sleeve!

Over the decade since I first started training as a T-permit holder I’ve experienced a few instances when birds do something completely unexpected. On Wednesday, I had just finished processing a Goldcrest but, when I opened my left hand to release the bird, it did not fly off immediately. It didn’t look stressed and certainly wasn’t hypothermic so I tilted the palm of my hand slightly to encourage it on its way. I wasn’t ready for what happened next.

In the flash of an eye, the bird rotated through 180o and then disappeared straight up the sleeve of the jacket I was wearing. Trying to work out where a bird weighing just 5 grams was hiding in a quilted sleeve was never going to be an option so I was left with no alternative but to gingerly slip my arm out and take the coat off. Gentle exploration located the bird at around about the elbow, whereupon it was easily extracted and flew off apparently non the worse for its brief experience as a troglodyte.

Wednesday 12th January 2022

Tristis Chiffchaff

The first ringing session of the year, with perfect weather, wind strength and direction. The reedbed is currently both unproductive and underwater so I concentrated on the area downwind of the sewage works. This proved to be a good call and 65 birds were trapped with 44 Chiffchaff, including 3 tristis and 2 UK control collybita. Also 6 Goldcrest, 3 Bullfinch, 3 Blue Tit, 3 Great Tit, 3 Robin, 1 Dunnock, 1 Blackbird and 1 Wren.

Two of the tristis were classic birds with olive limited to the margins of their flight feathers and tail and completely lacking in yellow tones except in the underwing coverts. A few years ago, the third bird would have been relegated unceremoniously to the form colloquially known as fulvescens, showing more olive on the mantle, a hint of yellow in the supercilium, undertail coverts and around the thighs. It was assumed that these birds were intergrades from the zone of overlap between tristis and abietinus. However, all the mtDNA analyses done on these birds for me by Martin Collinson’s team at Aberdeen University have come back as 100% tristis. Whilst this method only gives the maternal ancestry, I think it unreasonable to assume that hybridisation only occurs between male abietinus and female tristis.

The current thinking seems to be that if it looks like a tristis, sounds like a tristis and has tristis DNA then that’s what it is. Fortunately, all the birds were attracted into the net using a tristis song lure and gave the soft, short ‘peep’ call on release, which, as far as I am concerned seals the deal! I have posted photos of all three birds and a collybita Chiff below for comparison purposes.

tristis 1 with more olive than usual and a hint of yellow in the eyestripe.
tristis 1 – note hint of yellow in the undertail coverts and around the thighs.
tristis 1 – yellower underwing coverts than usual
tristis 2 – a ‘classic’ example
tristis 2 – note lack of yellow tones apart from faint underwing coverts.
tristis 3 – another ‘classic’ bird
tristis 3 – no yellow here either
collybita Chiff for comparison
collybita breast and underwing coverts

Tuesday 4th January 2022

The bridge to Marsh Ride on 3rd January 2022

Firstly, a happy new year to all those readers waiting anxiously for my next instalment. Don’t hold your breath!

I know from experience that, in the middle of winter, my mist nets beside the sewage works at South Milton Ley are only productive when it’s either flat calm or when there is an easterly element in the wind. The rest of the time the prevailing south-westerly breeze concentrates the chironomid midges and the birds on the opposite and inaccessible side of the works. With a seemingly endless stream of wet and windy westerlies in recent weeks, I have been keeping my carbon footprint low by staying at home.

To be honest, Covid vaccination commitments currently occupy two days a week and I also have an allotment, which desperately needs digging over prior to the spring planting season, assuming the ground ever dries out enough to work! With my main reedbed ride unproductive until the middle of March, there is little incentive to travel to SML. The flocks of roosting Reed Buntings, which used to form a significant part of the winter catch, are a thing of the past, with just one bird trapped this winter.

Added to this, the gradual and intentional silting up of the main drainage channel is beginning to have the desired effect of raising the water table in the middle of the reserve, (see the photo above), which means that, as a lone worker, I won’t risk accessing Marsh Ride. There’s over a metre of fast-flowing water under the bridge at the moment and another 60cm of soft sediment under that. The boards along the net ride are covered in a layer of silt, which turns them into a skating rink. It’s just too dodgy, trying to carry bird bags without slipping into the mire!

I haven’t been totally idle though. The first draft of the next management plan is completed and will be published as soon as I have addressed the comments received from various interested parties. I discovered that, deep in the darkest reaches of the Devon Birds’ website, someone has digitised all the annual reports from 1929-2018 into one massive pdf file. I have been searching this document for records relating to SML. I also have acquired a digital copy of “The Birds of Devon” by D’Urban and Mathews from 1892. Scouring both has enabled me to increase the bird list to 215 documented species. Only two of these, Little Bittern and Long-tailed Skua pre-date the establishment of the reserve in 1969.

If anyone wants copies of these two historical documents, leave a comment and I’ll stick them on Dropbox for you.