The following territory report is the work of Robin Griffiths, the volunteer warden of the Ravensroost complex, and his team of committed volunteers, on behalf of the Wiltshire Wildlife Trust, and is published here with his permission.
I will start with his summary report, including a link to the full report. I have then copied and pasted the Bird section from that report. After that I have added my own analysis of the implications of his report for the Marsh Tit population in Ravensroost Wood and the accuracy / reliability of territory mapping when done so on a single visit. This will be contentious given previous challenges to the viability of the Marsh Tit population in the Braydon Forest.
Robin’s Summary:
Ravensroost Bird survey 2026
The role of warden of Ravensroost includes doing wildlife surveys on the reserve, which include a butterfly transect and regular moth trapping and Brown Hairstreak egg searches. While the butterfly transect is exactly halfway through to date, the bird territory survey, based as it is on birdsong, finishes around or before midsummer day. This is because most birds stop singing around that time. The survey area is the same as the butterfly transect so does not included the whole wood.
This year there have been some interesting developments, some good, some bad. On the good side we have seen six species with increased numbers of estimated territories, of which two are significant. The Song Thrush went through a very bad patch around a decade or more ago with numbers dropping all over the country apparently for no obvious reason. I am happy to say that the Ravensroost bird survey reflects the bird’s recovery – territories in the last four years have increased as follows – 2 in 2023, 3 in 2024, 4 in 2025 and – I am pleased to say – 5 this year – those people who notice birdsong and have visited the reserve this spring will not be surprised at this as the Song Thrush song has been very prominent indeed. The other success story is the Nuthatch, the very typical woodland specialist – while the territory estimate for all three of the last years was 3 territories, this year there has been an apparent jump to 5! I have no explanation for this increase but hope it continues for this characteristic woodland bird.
On the down side, three species that seem not to have done so well are Coal & Marsh Tits and Spotted Flycatcher. The last of these, being a fairly elusive migrant that often seems to appear quite late in the season, sometimes accompanied by juveniles!, could well still be in the wood unseen so far this year – I do hope so as it is one of my favourite birds. Coal Tit is a surprise as its numbers previously were quite reasonable at 2, 4 and 3 territories respectively – but this year it seems to have declined to just a single territory. Finally Marsh Tit, the wood’s most characteristic bird to many of us. This year I have been unable to give it a single territory despite the fact that I know there is at least one, probably 2 pairs in the survey area. This is because during the 11 visits comprising the survey I have come on it just once. The rules of the survey dictate that I can’t give it a number unless there are at least two contacts on different dates. However Simon Tucker’s ringing results give a much better picture so this suggests the territories survey does not fairly assess the species’ true status. To be fair this has happened before, in 2024, while in 2023 and 2025 I estimated two territories.
The full results of this year’s survey is at Ravensroost Wood 2026 – Ravensroost Wood 2026 Report
(ST – I have extracted the bird section of the report, but you can reach the full report by following the link.)
Bird Section of the Full Report
BIRD ESTIMATED TERRITORIES SURVEY 2026 – 2023, 2024 & 2025 figures in brackets – (P = present but territory not established) Green = increased, Red = decreased, Arranged in order of abundance. Eleven visits were held weekly from April until June. Thanks to those who helped me with the visits.
Robin 13 (11,15,13), Blackbird 10 (9,9,9), Wren 9 (8,8,8), Chiffchaff 8 (6,7,8), Blue Tit 8 (10,8,9), Blackcap 7 (6,7,7), Nuthatch 5 (3,3,3), Song Thrush 5 (2,3,4), Great Tit 4 (4,4,3), Wood Pigeon 4 (2,3,3), Great Spotted Woodpecker 3 (2,3,3), Chaffinch 3 (4,4,3), Willow Warbler 3 (4,4,3), Crow 2 (2,2,1), Garden Warbler 2 (2,1,2), Jay 2 (2,1,2), Buzzard 1 (1,1,1), Long-tailed Tit 1 (1,1,1), Bullfinch 1 (1,1,1), Mistle Thrush 1 (1,1,1), Goldcrest* 1 (1,1,2), Coal Tit 1 (2,4,3), Raven 1 (1,P,P), Dunnock 1 (P,1,1), Stock Dove 1 (1,1,1), Pied Wagtail*** 1 (-,-,-)
Present but not established on territory: Red Kite P (P,1,P), Pheasant P (2,1,P), Treecreeper P (1,P,1), Magpie P (-,-,-), Goldfinch P (1,1,1), Marsh Tit P (2,P,2) – Marsh Tits, one of the special birds of the wood, are particularly elusive during the survey period – on non-survey days contacts were: one singing on 25th April, two calling in different parts of the wood on 8th June. The survey unfortunately is inadequate for assessiing the status of this species. Several juveniles were trapped and ringed by Simon Tucker during the period so breeding obviously took place. Redpoll – a single was seen on 7th April and a flock of 6 on 9th – probably lingering wintering birds, although they have bred in or near the reserve in the past.
No records this year: Spotted Flycatcher** – (P,P,P), Tawny Owl – (-,-,P) – this only applies to the survey – birds are present and are often heard at night, Jackdaw – (2,1,1)
*Goldcrest – I have recently realised that due to hearing deterioration I cannot hear Goldcrests and maybe some other birds except in very exceptional circumstances.Therefore results for Goldcrest and maybe Treecreeper as well cannot be relied on. This came to my attention last year when I was away and Jane did the survey in week 11 – she heard 3 separate Goldcrests when the most I had heard during the season was 2 in week 2 and 1 in week 10, and no other contacts.
**Spotted Flycatcher – For the first time for several years no contacts were made with Spotted Flycatcher during the survey period – nor any reports from other observers
***Pied Wagtail – for the first time in years a Pied Wagtail male was seen on the survey route on three occasions from 29th April to the 28th May, carrying food on 15th May. It must have had a nest nearby though probably not on the survey route itself. These sightings reminded me of the situation in Finland where the White Wagtail seems to be a woodland species.
End of Section
Obviously, the lack of Marsh Tit territory data concerned me, having been monitoring the species since 2012, but been involved in ringing and recatching them since I started ringing in 2009. This prompted me to look at my data, as a previous territory survey found similar results and, despite our ringing records, that surveyor claimed that our population in the Braydon Forest was insignificant. As regular followers of the blog will know, that prompted so many other posts, ending up with last year’s magnificent 5.5% of all UK Marsh Tits ringed in England being ringed in the Braydon Forest. The Ravensroost complex has always been a key component of that population, so I wanted to be sure that things weren’t going awry.
What I decided to do was to look at the numbers, in the following categories: Marsh Tits ringed by year, both adult and juvenile; juveniles ringed by year, individual birds captured by year (i.e. birds caught multiple times in the year were counted just once) and then total captures by year (i.e. ringing catches, recaptures counted in total). These are the results:
As you can see, six months into the year we are above average for full years across all categories. That is encouraging, but when I just look at the first six months of this year, there is every reason for a great deal of optimism:
I have no idea of what went wrong in 2021. We did a similar number of sessions to the norm, with average size catches, since I completed the coppice cycle project in 2021.
Across every category, there is nearly a 100% increase on the average at this date. For the sake of statistical accuracy, I have included this year’s figures in the average. If I remove them and recalculate, the result is even more encouraging:
The last few years we have focussed on the 8-year coppice area but, for the rest of this year, I plan to split our sessions between the coppice and the natural growth area of the wood. I expect the results to be hugely improved by that. All in all, I am hopeful that we will exceed the numbers we achieved last year and, perhaps, increase the significance of the Braydon Forest as a haven for this threatened species.