Green Lane Wood & Biss Wood: 21st & 22nd February 2021

The following blog post is by Jonny Cooper.

With the guidelines for ringing being revised I was keen to visit some of my sites to see how the birds were doing. Near the top of the list were Green Lane & Biss Woods. This reserve complex on the outskirts of Trowbridge consists of two woodland areas linked by mature hedgerows and areas of scrub. For the purposes of ringing each woodland is treated as a separate site.

The weather for Sunday and Monday was looking a bit hit and miss, so it was with some trepidation I headed to Green Lane Wood on Sunday. As it happens, the forecast rain never really materialised with, at worst, some light drizzle. The session was as expected: very heavy on the titmice, with a few other species in between.

The highlight was a bird that evaded the nets: a lovely male Lesser Spotted Woodpecker, which made itself known towards the end of the session. Overall, 53 new and 28 re-traps were processed, giving a total of 81 birds.

I woke up Monday morning ready to ring, to see heavy rain out of my window, so back to bed I went. Thankfully, the rain passed over and by lunchtime the sun was shining, so I headed to Biss Wood to do a short afternoon session around the feeding station. The session was very similar in its make up to the previous day, with large numbers of titmice caught. Overall, 55 new and 32 re-traps were processed, giving a total of 87 birds.

The full breakdown for both catches was as follows: Great Spotted Woodpecker 2, Nuthatch 4, Blue Tit 67(37), Great Tit 13(16), Coal Tit 4(2), Long-tailed Tit 3(5), Dunnock 4, Robin 2, Song Thrush 2, Blackbird 2, Goldcrest 1, Chaffinch 4. Giving 108 birds ringed from 12 species and 60 re-traps from 4 species giving an overall total across the two sessions of 168 birds processed from 12 species.

Two sessions that were very much as expected, but it was great to be able to get out ringing again.

Hello again! It’s been a long time!

Back on the 6th January bird ringers in England were instructed / strongly advised by the BTO that, although being a voluntary activity excluded from lockdown by the government guidelines, we should confine ourselves to within the boundaries of our property to avoid “reputational damage” to the BTO and the ringing scheme. Subsequently, the birds seemed to desert my garden and between then and today I had processed precisely 2 birds: both recaptured Blue Tits.

On the 12th February we received a second email from the BTO which said that our surveys were legal and unlimited, with no mention of the previous concern about reputational damage and sticking to the boundaries of our property. Naturally, immediately upon receipt the weather took a huge turn for the worse and ringing was impossible anywhere, either in the garden or on my sites. Today was the first day since then that I have been able to get out. I knew it would be windy so I decided that Red Lodge would be the best site: a small number of nets focused around 2 feeding stations.

On Friday last I set up the feeders at my various local sites and yesterday I went over to top up the feeders at the sites to be visited this week. I was pleased to see that the birds had been tucking in to the food at Red Lodge and was looking forward to a good catch. Lucy joined me for a 7:00 start and we set up just 4 nets: 2 x 18m in a line plus 1 x 9m and 1 x 12m each adjacent to a set of feeders.

It was clearly going to be Blue and Great Tit heavy and, in fact, outside of those two species we only had birds from 3 other species. The first non-Blue / Great Tit was a new first winter Marsh Tit, our second of the year. Next into the nets was a Robin hotly pursued by this guy:

Fortunately for the Robin it hit the net just high enough away from the Sparrowhawk to be out of its clutches. Whilst Lucy removed the Robin, I took out the Sparrowhawk. Both birds were processed and released unharmed.

The list for the morning was: Sparrowhawk 1; Blue Tit 25(5); Great Tit 4(5); Marsh Tit 1; Robin 1. Totals: 32 birds ringed from 5 species and 10 birds recaptured from 2 species.

The wind became excessive at just after 10:30, so we shut the nets, packed away and were off site by 11:30. The weather is looking good for the rest of the week, so I am planning to get several sessions in, starting at the Firs tomorrow, then Lower Moor Farm on Thursday, Blakehill Farm on Friday and Somerford Common on Saturday. That should cure my withdrawal symptoms!

West Wilts Ringing Group Results: January 2021

Not our best January, with just three sessions away from our gardens, at Langford Lakes, Meadow Farm and Somerford Common on the 1st and 2nd January. Lockdown instructions from the BTO on the 6th January put a stop to any ringing away from your own property.

It isn’t our lowest ever January catch: between 2013 and 2017 only 2016 was a better January than this. Since then we have had much higher catches but compared to last year though it really was a low catch – so I haven’t done a year-on-year comparison, as there is no real value in it.

Jonny was lucky enough to get our first Water Rail since 2009 (apart from my first on Skokholm in September 2019) and his first, and the first caught at Langford Lakes. 

Although I have done plenty of Pied Wagtails as a trainee, and one at Blakehill Farm, I was fortunate enough to catch my first one for my garden this month:

It doesn’t look like we will be getting out again any time soon and, I don’t know about anyone else, but the birds seem to have abandoned my garden: 2 birds yesterday, and Ellie had 1 bird caught in her garden today. It is not looking good for February!

Recovery Updates

The ringing recovery maps and data have been updated with the 2020 recoveries.

These include new UK movements for Goldcrest; Blackcap; Reed Warbler; Cetti’s Warbler and Blue Tit plus our first long distance raptor recovery: a Merlin.

New foreign recoveries are a Spanish Reed Warbler and, astonishingly, an Icelandic Meadow Pipit.

A big thank you to Jonny Cooper for his hard work in collating the data and producing the maps.

Causes of Mortality in Wiltshire Recorded Bird Fatalities: 2017 – 2020 Inclusive

The point of ringing birds is that it makes each bird individually identifiable, thus allowing ongoing, quantifiable analysis of traits, populations, etc.  This enables ringers recapturing birds to record the following on an individual basis:

  1. Age
  2. Movements
  3. Compare condition over time
  4. Monitor breeding condition (including sexing monomorphic species)
  5. Identify and collect, where possible, the details of their death

This last is something that is often informed by members of the public, reporting a ringed bird found dead to the BTO.  The finder gets a report back from the BTO telling them when and where the bird was ringed.  The ringers gets a similar report with the details of where it was found dead and the cause of death, where reported.  Unfortunately, the cause of death is not always capable of being identified, but often it is.

Phil Deacon diligently records all recaptures of birds that are recorded by the BTO that have either entered or left Wiltshire, whilst moving either on migration or post-breeding / post-fledging dispersal. Within that he also records all fatalities reported to the BTO.  This is a brief analysis of that mortality data, collected between 2017 and 2020.

The first thing I looked at was the recorded causes of death:

Clearly, the recording of death is a very patchy affair, with some 35% of causes not being recorded, or not being able to be recorded.  Unsurprisingly, the largest, identifiable, causes of death are the domestic cat, followed closely by windows, and then traffic.

Surprising to me was the number of birds that drowned in water butts / artificial ponds: 2 Barn Owls and one each of Blackbird, Nuthatch and Great Tit.

Of those shot, 3 were Teal hunted in Finland, Russia and France.  Killed illegally was a Grey Heron, ringed at Swindon Sewage Works but shot elsewhere in the Swindon area four years later.  That is hard to understand.  There was also a Cormorant ringed as a nestling near Anglesey and shot just 7 months later near Lower Woodford.  Although it is possible to get licences to kill Cormorants, to protect the profits of angling clubs, to kill a bird that was clearly juvenile seems wrong to me.

It is hard to understand why Woodcock (2) and Snipe (1) are still considered game species.  In the UK Woodcock are red-listed, and Snipe are an amber-listed species, due to population declines here. I am aware that shoots based in the Braydon Forest area restrict their shooting to the released Pheasants and Red-legged Partridge they release for the purpose but I am surprised that it is a matter of individual restraint. If there is little meat on the bones of a Snipe, who on earth shoots Redwing? Someone in France it would seem.

Of the 138 recoveries the largest cohort was the Barn Owl by a significant margin. They are striking birds that are difficult to overlook, are regularly found around human habitation and are a closely monitored species.  Looking at how their deaths break down is quite instructive:

The term building is used loosely to cover, in this case, barns and one that is a large open space, but man made and managed.

Barn Owls are known to be frequent road traffic victims, and this is underlined by the figures shown here: far and away the commonest reported cause of death.  

There are some intriguing cases here though: two of the four killed within buildings / man-made structures were found in the same barn in Pewsey on the same day. I would be keen to know what would cause two of these iconic birds to perish simultaneously but, unfortunately, that has not been recorded.

Another of the birds found dead in a man-made structure was one found in the lion enclosure at Longleat Safari Park, again the location is given but not the cause.   I suppose a slow, low flying bird might well tickle the fancy of a bored lion.

What are the chances that one of the rarest birds in Wiltshire, a Montagu’s Harrier, would end up as a road casualty? That is what happened to a juvenile ringed in Wiltshire and hit by a car just over the border in Hampshire 30 days later. 

Talking of rare birds, a Merlin ringed on the Shetland Islands in 2016 was recovered dead, having collided with electricity cables at Stanton St Bernard three years later.

The total casualty list by species is as follows:

Many thanks to Phil Deacon for his hard work in collating the data and for giving me permission to use data from outside the West Wilts Ringing Group in preparing this post.

West Wilts Ringing Group: 2020 Annual Summary

Introduction:

The activity levels within the group and, consequently, the number of birds processed, continue to increase. The reasons for this are twofold: the imposition of restrictions to deal with Covid-19 forcing individual sessions for those licensed to carry them out, and the fact that we now have six active C-permit holders in the group.  Jonny is particularly active and, as much as I hate to say it, it is primarily his contribution that has driven the increase this year. He has managed to get some very productive sites to add to his already strong portfolio of East Tytherton and Meadow Farm, processing over 43% of our catch, whilst holding down a job as well!

On a per session basis the numbers are lower: but that is because so many sessions this year were carried out in our gardens or, failing that, single-handed exercises under restrictions placed by the landowners, where either numbers are not so good, or caution was needed because the catch could potentially be very large.

The Catch:

So, a significant increase in both birds ringed and recaptured during the year, but not a significant change in the number of species caught. However, the total number of species caught over the two years is 70: so, clearly, there is a decent variety in the catch.  Since 1st January 2013 the group has actually processed 79 species.

What is rather surprising, given that we have carried out approximately 30 more sessions than we did in 2019, and so many were garden sessions, the numbers of Blue and Great Tits processed are pretty similar year on year.

Not represented in the catch last year but present this were: Collared Dove, House Martin, Jackdaw, Kestrel, Long-eared Owl and Nightjar.  Present in 2019 and missing in 2020 were: Brambling, Buzzard, Firecrest, Merlin, Swift, Tree Pipit and, unsurprisingly, Sykes’ / Booted Warbler.

One thing that has been quite remarkable is the astonishing number of Meadow Pipits.  In 2018 Jonny and I had an excellent couple of catches at Blakehill Farm.  This tied in with the plateau area where we ring in the autumn not being cropped for hay, left for grazing, and the most amazing irruption of crane flies.  2019 was similar – but we were away at the end of August / beginning of September and missed part of the influx.  This year Blakehill was back to producing a very similar number to 2018 but this time Jonny set up Mipit triangles at East Tytherton and Meadow Farm and caught 164 and 197 respectively.

There are clearly some remarkable birds again this year: Nightjar and Long-eared Owl are firsts for the group.  Our catch of 30 House Martins at New Zealand Farm was just astonishing and Dave had a superb catch of 6 Jackdaw in a single session.

Photos courtesy of Dr Ian Grier

New Sites / New Projects:

Thanks to interest and permission from the Wiltshire Wildlife Trust, Jonny Cooper has taken on a couple of new projects. The first is a breeding season reed bed project at Langford Lakes, and it looks like a very promising development, as evidenced by the increased numbers of Reed and Sedge Warbler in the catch.  Although that increase in those two species is also in part due to his continued activity at the Western Way Balancing Ponds in Melksham.

More recently, he has taken on a winter monitoring project at Biss Wood, which has been modified to incorporate Green Lane Wood as well, being one extended nature reserve complex to the east of Trowbridge. The catches there have been remarkable in size if not variety.

At the start of the first lockdown, with the support of Richard Brown, the warden on Skokholm, I advanced Alice to a C-permit so that she could continue to develop her skills in her parents’ back garden.  She has continued to prove her competence and now she has started a new project at the Hogacre Common Eco-Park in Oxford, where she is working on her PhD.  This is a little oasis of habitat in the middle of a number of college playing fields and it will be interesting to see how it develops.

Non-Group Ringing Activities:

Andrew Bray continued his work with the North Wilts and those sessions with Graham and Phil Deacon in 2020 has produced the following:

Table 2: Andrew with the North Wilts Ringing Group:

Alice joined the SCAN ringing group (North Wales) for two weekends at the start of 2020 (24/01/20 – 26/01/20 and 7/03/20 – 8/03/20).  In January cannon netting and mist netting for waders, and in March cannon netting for Shelduck.

Table 3: Alice with SCAN:

Azores: From 13/08/20 – 12/09/20 Alice was a field assistant for a PhD student at the University of Cardiff, monitoring Storm Petrels on a tiny islet off Graciosa, Azores (see blog post of the 24th September for further details).

Table 4: Alice mist netting on the Azores:
Table 5: Retrapped pulli: nest checks were conducted every day and chick ring number and biometrics were recorded (wing length, tarsus, weight)

Alice also joined the Edward Grey Institute (EGI) at the University of Oxford in Wytham Woods for two ringing sessions in November. 

Table 6: Alice with the EGI:

New Recruits:

This blog has become a source of recruitment for the group.  Notably, Alice joining us in 2019.  This year I was contacted by Lucy Mortlock.  Lucy was working on field studies in Northern Ireland during the Spring and Summer and was looking for a ringing group to join, having returned home to Wiltshire to continue her degree (at Reading University – an excellent choice if I might say so myself).  She contacted me through the blog and is now, when lockdown allows, a regular member of my ringing crew. 

Garden Ringing: Friday, 15th January 2021

Now that we are confined to ringing only in our gardens again it seems that the flocks of Goldfinch, and those of Starling, have disappeared. Today’s session was so much better than Monday’s, although 14 birds compared with 6 is not too much to shout about, it was the quality of the catch that made the difference.

I opened the nets and set up some Potter traps baited with dried mealworms and put on lures for Goldfinch and Starling. Whilst heading back indoors a Pied Wagtail flew across the drive and into next door’s garden. I muttered something rude under my breath as it narrowly missed one of my nets. I was just on my second mug of tea when the net suddenly jerked and there it was:

This is a first winter Pied Wagtail: and the first that I have caught in the garden. The yellowish tinge to the face is a clear juvenile characteristic as are the unmoulted greater coverts. Along with this, there were a couple of Goldfinch: both first winter and both females. Next into the nets was a rather good looking Starling:

I changed the lure on the apple tree to Greenfinch and half-an-hour later I took this fabulous first winter male out of the net:

I loved the attitude and thought that it reminded me of something else. A quick Google search and I found what I was looking for:

They could be twins!

The last bird I took out of the net was an adult female Goldcrest:

Soon afterwards I looked out of the kitchen window and saw the neighbour’s cat sitting under the apple tree, clearly looking for the Greenfinch singing its heart out in the branches. That decided me that it was time to do three things: chase off the cat; close the nets and pack up and recharge my solar powered cat scarers (there hasn’t been a lot of sun to keep them going.

The catch for the session was: Blue Tit 2(2); Great Tit 1; Dunnock 1(1); Pied Wagtail 1; Goldcrest 1; Starling 1; Goldfinch 3; Greenfinch 1. Totals: 11 birds ringed from 8 species and 3 birds retrapped from 2 species, making 14 birds processed from 8 species.

Early Courting Dunnocks

We have been asked by the BTO not to ring outside of the boundaries of our property whilst lockdown is in force, as they are concerned that it might reflect badly on them if we are seen out ringing. Personally, I rarely ever mention the BTO when on a ringing session. They provide the licence that allows me to do it, but it is the landowner who decides whether or not I can carry out the work on their property. The DVLA provide me with my driving licence, but if I get caught speeding I don’t think the DVLA need worry about damage to their reputation.

Indeed, if anybody ask, I tell them I am doing a volunteer survey on behalf of the landowner, so they know what is happening on their land, which is genuinely how I see it and how I work. It is why I end up writing so many reports (session reports, annual reports, trend analysis, love it!). I briefly opened my nets in the garden this morning. Briefly because it quickly became too windy and I closed them again about 40 minutes later. Should have done it yesterday, when it was calm all day, but I was busy on other things!

Anyway, despite that, and only catching six birds in the short time the nets were open (Blue Tit 1(1); Dunnock 2; Robin 1; Goldfinch 1), the Dunnock catch was interesting.

Back on the 5th December my wife asked me if it was likely that Dunnock would have newly-fledged young this late in the year. What she witnessed was a food begging and wing fluttering display. That is something newly fledged young will do, but it is also part of a courtship display, with a female begging to an attentive male. It has been very mild, so are they gearing up for an early start to the breeding season? I have noticed that there has been a lot of Dunnock activity in the garden and a lot of calling from tops of bushes and small trees. Anyway I thought nothing more about it until this morning.

The two Dunnock that I caught this morning were very definitely male. Being sexually monomorphic you can, generally, only tell them apart in the breeding season. With the average laying date for first clutches being the 27th April, with the earliest first clutch being recorded on the 1st April (thanks to the BTO Bird Facts and data in the Nest Record Scheme), it does seem awfully early for the male to have developed the distinctively enlarged cloaca (known as a cloacal protuberance) this early in the year. It seems like a lot of energy to expend to produce the extra bodily fluids needed to engorge that part of the body.

Trust me: of all the sexually monomorphic passerine species, the male Dunnock is the easiest to positively identify as male.

Being intrigued by this I thought I would have a look in the online database at our group records, going back through all of the records (even to pre-IPMR days, which is probably only meaningful to other ringers), even into records from the 1990’s. In that time the group has processed over 9,000 records of Dunnock. They have identified just under 1,900 of those records as being male. Amongst them there have only been two other January records of identifiably male birds: on the 23rd January 2005 and the 24th January 2009 (the latter being just a couple of weeks after I started my ringing career).

That makes these two birds the earliest we have ever recorded as male by just under 2 weeks! Is this likely to become a trend, with our ever milder winters? It will be interesting to see.

Hogacre Common Eco Park

This is a summary of the activities of Alice, one of my C-permit holding trainees. She is currently working on a PhD at Oxford University and, because of travel, Covid-19 restrictions (between lockdowns), was able to find Hogacre Common Eco Park and get permission to ring there.

The site is adjacent to the sports grounds of a number of Oxford colleges. It is early days yet at the site. It can take a year or so to get the optimum net positions, unless you are lucky.

This is Alice’s summary of her activities on the site in November and December 2020:

Between the 10th November and 15th December 2020, six bird ringing sessions were run at Hogacre Common. Just over 100 birds were processed from ten different species (Table 1, Fig.1). Since these were the first bird ringing surveys at Hogacre, most individuals caught were ‘new’ birds that had not previously been ringed (85%); while 15% of birds were retrapped in a subsequent session. Over 25 species were observed on site during the surveys, with two Lesser Redpoll being a particularly pleasing sighting in mid-November.

Table 1 Number of new and retrapped individuals of each species caught between the 10th November and 15th December 2020.
Fig. 1 Number of new and retrapped individuals of each species caught from 10th November – 15th December 2020.

The following list is of bird species seen/heard at Hogacre Common from November – December 2020. It does not include birds flying over that were not using the site: Mallard; Moorhen; Pheasant; Woodpigeon; Collared Dove; Buzzard; Red Kite; Sparrowhawk; Kestrel; Green Woodpecker; Great Spotted Woodpecker; Dunnock; Wren; Blackbird; Song Thrush; Redwing; Fieldfare; Robin; Goldcrest; Chiffchaff; Blue Tit; Great Tit; Long-tailed Tit; Nuthatch; Magpie; Carrion Crow; Goldfinch; Chaffinch; Lesser Redpoll.