Marsh Tit, Poecile palustris
As regular readers will know, I have been carrying out a particular study on Marsh Tits in the Braydon Forest since August 2012. The species is red-listed because of the precipitous decline in the UK population. There are many suggested reasons for the decline but the key, undisputed reason, is the loss and fragmentation of UK woodlands. That is particularly significant for this species because Marsh Tits are renowned for being highly sedentary: with a statistic of fewer than 5% of them moving more than one kilometre from where they fledged, being quoted quite regularly. Thankfully, partly as a result of my reporting back to them, Forestry England have made the Marsh Tit their priority bird species for management of their holdings in the Braydon Forest.
My project has involved putting coloured plastic rings, alongside the unique metal ring, on birds when caught. Some people do get their knickers in a twist over colour ringing, but the point of it is to enable individual birds to be uniquely identified by observers, without the need to recapture them. The project is authorised by the British Trust for Ornithology, and they instruct the project manager, i.e. me, on the scheme to be used. In the case of my project, the lower left leg has a metal ring above a colour ring, and the right leg has two colour rings. The colour rings are made from very lightweight plastics that will hold their colour for the three years or so: longer than the usual life expectancy of an individual bird, given as 2 years on the BTO BirdFacts section. Mind, the longest known age of a Marsh Tit is 11 years and 3 months from the date of ringing. From a Wiltshire-centric point of view: the second longest known survival in the UK is a bird ringed in Clattinger Wood, nr Westbury, on the 24th June 1984, and recaptured 10 years 1 month and 6 days later on the 30th July 1994 in the same place. The longest gap I have in the Braydon Forest, between ringing and last recapture, is D056635, at 4 years 11 months and 10 days. The subject of this blog has the second longest gap between ringing and last sighting (in this case) of 3 years 11 months and 27 days.
I won’t pretend that I get hundreds of sightings reported but, when I do, I am extremely grateful and provide a full breakdown of the details I have on the bird to the observer reporting back to me. This Saturday, contacted through the blog, I was sent a sighting by Simon Gathercole, from Somerford Common. On the 8th March he saw a Marsh Tit with a silver ring over green on the left leg and orange over yellow on the right leg. In putting together the data for this bird I found out that it was ringed in the Firs nature reserve. So, bearing in mind the statistic quoted in paragraph one, this is an unusual situation for the species. When I enter recaptures the database doesn’t automatically show you the previous sites at which it has been ringed and / or recaptured. Looking back over my records, of the 215 Marsh Tits that I have ringed in the Braydon Forest only one other has moved over 1km from where it was fledged. In fact, only two others have actually moved away: D056930 moved to the Firs from Webb’s Wood and then back again, but that is a distance of less than 700m. The only other to have moved over 1km was D983277, which moved from Webb’s Wood to Red Lodge, a distance of just under 3km. This bird was probably a juvenile dispersal, as it was ringed as a juvenile in June 2014 and recaptured in January 2015 in Red Lodge.
So to the subject of this post: AAL0191. It was ringed in the Firs on the 21st February 2020 and over the next two years it was recaptured six times: with the last being on the 9th October 2022. It was also reported from a field observation on the 8th February 2022. Very much the epitome of a sedentary bird. However, the next time it was recaptured was on the 22nd November 2023 at Somerford Common, a distance of just under 2km. Not a big deal, unless it is a species that is as highly sedentary as the Marsh Tit. So, this was not a juvenile dispersal, so what prompted it?
The last time it was recaptured in the Firs, as noted, was 9th October 2022. That happens to be the last time that I was allowed to carry out a session at the Firs. Why? The site’s landowner is Hill’s Waste Solutions. It is managed on their behalf by the Wiltshire Wildlife Trust. In October 2022 the Trust were instructed by Hill’s to remove all of the Ash trees on the reserve, to mitigate the effects of the Chalara Ash dieback disease and remove any possibility of visitors being injured by trees / branches falling. Hill’s also recommended the contractors to be used. As a part payment for the work, the contractors were also allowed to remove a quantity of the mature Oak trees on the site. Without going into too much detail, after they completed the Ash and compensatory Oak removal, the site was left with the paths destroyed, something the contractors were supposed to have resolved before leaving site, and the site is now deemed too dangerous to allow the public back on site. The Trust have not had the funds available to bring the site back to a safe state for public access. Consequently, I have not been allowed to carry out any additional survey work there. That is a shame because it would be interesting to know what the situation is for the birdlife on the site. If, as I suspect, the disturbance at the site was the reason for this Marsh Tit’s dispersal, it would be really interesting to see what other species have potentially been affected. I would have liked to have been back in there soon after the contractors moved out, to gauge impact, but Health & Safety rules, no matter how many waivers or indemnities one is prepared to sign up to.
Ironically, depressingly, that last session at the Firs was a good one: Treecreeper 2(1); Blue Tit 14(4); Great Tit 7(6); Marsh Tit 4(1); Long-tailed Tit 10(1); Wren 2(1); Robin 6(1); Chiffchaff 1; Goldcrest 5. Totals: 51 birds ringed from 9 species and 15 birds retrapped from 7 species, making 66 birds processed from 9 species.
Ringing In The Braydon Forest & Beyond 