Curlew Forum Newsletter 2, 30 June 2017


A chick at West Sedgemoor, Somerset, June 2017 (Richard Archer)

Introduction

Since the previous Newsletter we have made contact with another team studying a regional breeding population of Curlew in southern England – in East Anglia.  So this issue includes a note from Jen Smart and Rob Hawkes on Breckland, as well as updates on the course of the breeding season in other lowland sites in southern England.  Are there any other populations of breeding Curlews in southern England we have overlooked?  Let us know of any gaps in our network: how about Exmoor for instance?  The third Newsletter at the end of August will give a preliminary assessment of the 2017 breeding season.  The reports in the present Newsletter suggest that there has been great loss of nests this year, notably from predation by foxes; one poultry-fancying correspondent comments: ‘You can’t rely on daytime predation being avian and not fox.  I was surprised to hear that a temperature logger on eggs going cold at 5 p.m. implied corvid predation, on the basis that a fox wouldn’t have been active at that time of an early summer afternoon.  From my experience as a small-scale free-range poultry keeper you can’t make that assumption.  I let my hens out sometime between 7 and 9 a.m. and shut them at about 9 p.m.  We have had hens go missing three times this year so far – once in May sometime before dark, then twice in broad daylight sometime between 2 p.m. and 6 p.m. with feather evidence to show that there had been an attack.  I have also seen an adult fox patrolling the neighbourhood in a familiar confident manner during the afternoons this summer’.

The Forum’s informal steering committee met again in early June and is planning a small meeting in early October involving representatives of all the regions of southern England regions reporting here.  The purpose of the meeting is to provide information for Geoff Hilton who is to speak up for southern Curlews at the meeting of the UK and Ireland Curlew Action Group on 17 October; and to discuss just how the southern England Curlew Forum should move forward: do we need some kind of umbrella organization, specifically to study and monitor breeding Curlews in southern England, to suggest improved conservation measures and greater public awareness of these populations?  And if so, how is this to be financed?  Or can this same aim be achieved by existing bodies?  We hope in the near future (if possible before the October session) to set up a website on breeding Curlews in southern England, with a facility for any observer to post observations, comments or questions.

Advance notice of another “Call of the Curlew” workshop being organized by Mary Colwell: this is to discuss the situation in Wales, and will be held at the Royal Welsh Showground, Builth Wells, on 24 January 2018.

As always, any comments on the Newsletter and on the broader topic of breeding Curlews in southern England can be forwarded to smartmike143@gmail.com

Notes from the regions on breeding Curlews in May and June 2017

Cornwall

There’s really not much to tell.  Two pairs on Bodmin Moor but very mobile and given the geography of the large area it’s been hard to work out what they were doing or where.  Hoping next year to be more organized and have some extra eyes and ears – not an easy place to watch.

Claire Mucklow: claire.mucklow@rspb.org.uk

Dartmoor

Very quick update from Dartmoor:

  • Disappointing results again from Dartmoor. Four territories remained occupied from April – 21 June. One pair nested and failed at egg stage with a replacement clutch not confirmed.
  • The other three males remained alone on territory however a second female arrived in early June to join one of them – I ‘m now watching to see if they have attempted a late clutch; I’ve only seen one bird since so it’s possible she is sitting.
  • I expect the other males to leave now that the longest day has passed.
  • So in conclusion – four territories – two pairs and two males. One nest known but failed at egg stage.

Jon Avon: jon.avon@virgin.net

Somerset Levels: West Sedgemoor

  • We’re in the first year of looking at Curlew breeding productivity on West Sedgemoor, so it’s a bit of a learning curve for the local team. Weather conditions have been very dry in April and May, with species-rich hay meadows in the core breeding zones pretty arid. This may explain in part why numbers seem to be down this spring.  With breeding Cranes on the southern side of West Sedgemoor all our Curlew work has been confined to the north side of the moor – understandable but a bit frustrating.
  • Nest-finding began in earnest from 24 April. In the early season to mid-May we were able to locate nests by following birds around fields using telescopes deployed from a truck.  Birds didn’t seem to tolerate human presence from less than about 200 m, but were often quite relaxed with surveyors in a truck at closer range. Once field vegetation reached 12 inches or more, we had to rely increasingly on cold searching fields and hoping to flush incubating birds.
  • We estimate the north side of the moor held up to nine pairs this spring, of which four first clutches have been predated; three first clutch pairs have broods currently and one first clutch nest is still incubating. Another pair have been very elusive but probably were predated and haven’t re-laid.  This gives us a nest predation rate of about 50% so far (excluding the elusive pair whose status is uncertain).  In addition, we have a probable predated first clutch pair incubating a new clutch.
  • All of our pairs are nesting in unimproved hay meadows – mostly MG8, MG13 or MG9, and conspicuously away from the main north side drove, although some adult Curlew have made occasional use of cut silage fields near the drove in the last fortnight. Using the nesting data, our reserves team have liaised with our tenant farmers to delay introducing cattle to fields, and we will work with them to encourage hay cut after 12 July to give unfledged chicks a chance to escape the mower.
  • Temperature loggers are proving very valuable when assessing predation and hatching events. The timing of one of the hatches suggests at least one pair started laying on or about 18 April, around the time that Mike Smart found a nest on the Gloucestershire Hams. Where possible it seems sensible to start looking for territories and nests from at least mid-April, and in future years we hope to start monitoring earlier than 24 April.
  • Our three pairs with broods have so far remained in their nesting fields. At least one brood is three weeks old, which is encouraging. We have managed to radio tag two chicks from one brood so far, and they are now a week old and the radio tags remain in place.  We hope to tag up to five more chicks, possibly from just the two remaining nests.  If we are able to get on to the south side of the moor we will deploy some of the remaining tags on other broods to get a better spread of brood tagging.  Sadly, we weren’t aware of one of the nests during incubation until the adults started alarming with chicks, and a further clutch hatched during a week of heavy rain when we didn’t go out to monitor.  We will know better next time!
  • Technical support for the project has been brilliant, especially from Jen Smart in our Conservation Science team at RSPB HQ, and our radio taggers, with special mention to Jez Blackburn at BTO and Rich Hearn at WWT for helping us out at short notice, and Alison Morgan, our local ‘ringing vicar’.

Richard Archer: richard.archer@rspb.org.uk

Leah Kelly (Project MRes student): Leah.Kelly@rspb.org.uk

Severn and Avon Vales, Gloucestershire and Worcestershire

  • The breeding survey carried out in the Severn and Avon Vales in Gloucestershire and Worcestershire in 2016 (and 2015) has been repeated this year, with improved coverage. In general most of last year’s sites have been occupied again (at least at the beginning of the season, though not all pairs have necessarily bred); one or two new sites away from the river valleys have been found, notably one in the Forest of Dean, and several between the Severn and Avon in mid-Worcestershire. The final total is likely once again to be just under 40 pairs, at least holding territory.
  • Exchanges with other members of the Curlew Forum and visits to other areas have made us aware just how varied are the habitats used by Curlew, and just how special are the Severn and Avon sites. Most of the birds in the latter area are nesting in huge hay meadows near the river (like the Upper Thames Valley in Oxfordshire, and comparable to some extent with the West Sedgemoor); by late April the grass is so long that the Curlews disappear on landing, so the chances of finding nests are pretty slim; we are not convinced it is necessary to find the nests, because of the danger of disturbing the birds and of showing predators the way to the nests, not to mention the damage to often privately owned hay crops.  So our methodology is pretty simple: watch on foot from afar with a telescope, if possible from higher ground, (sadly no truck available), and judge breeding success in late June (or more probably July) when we see the fledged youngsters.
  • We have become more and more convinced that the classic standard method of monitoring waders (monthly visits in April, May and June, with a national co-efficient applied to the results) does not give an accurate picture of the numbers and success of breeding Curlews. Visits need to be carried out from March to July, and at much more frequent intervals.
  • We have managed to find four nests, three of which were predated. From the behaviour of the adults we suspect that many other pairs have lost eggs or young to predation.  But there are some places where the behaviour of the parents suggests they have succeeded in hatching young.  It is often hard to judge, since the birds often went very quiet when they presumably had eggs in May; there were times when, on one visit, it appeared that the birds had vanished, only to reappear from the long grass on the next visit.
  • The mid-June heat wave coincided with the first permissible date for hay-cutting under many Higher Level Stewardship agreements, which is often 15 June (much too early for Curlews to our way of thinking; we need to review this with Natural England). A number of Curlews lost eggs or nests in ideal hay-making conditions at this time.
  • Observations of Curlews have been combined with recording of the botany of the nesting fields. In most cases they nest in floristically high quality fields, often in the lower lying sectors where the grass is slightly shorter.  At least this should result in better data on the best hayfields in our area.

Contacts have continued with the Floodplain Meadow Partnership who are very interested in joint work on the botany and ornithology of hay meadows. There is a potential conflict between best cutting dates for nesting Curlews (the later the better) and the best cutting dates from a botanical perspective (not too late, or the most interesting hay meadow species may be smothered by coarser plants).  It should be possible to reach a compromise if the location of the best botanical meadows is known, and if they are monitored to check on presence of breeding waders that require a late cut, though that will require a lot of survey.  The Floodplain Meadows Partnership has produced an article on when to cut from a botanical point of view at: Article on meadow cutting

  • A visit to one of the best sites, Upham Meadow (a Lammas Meadow where hay cutting is carried out in the traditional slow and gradual fashion from mid-June until late July), was arranged by the Gloucestershire Invertebrates Group, one of the aims of the visit being to discover more about the invertebrates available to Curlew on the site. A note by John Phillips is appended; it makes some very interesting speculations about the value of the traditional hay cutting method for conserving high invertebrate biodiversity.
  • In organizational terms, we have continued with a small team of experienced observers, but have received additional help from Worcestershire, where Ian Duncan is making observations this year and has volunteered to as central organizer for Worcestershire next year.
  • At the Severn Ham in Tewkesbury work has continued with the Environment Agency, to monitor possible disturbance to breeding Curlews from their major works on weir refurbishment; the signs requesting dog-walkers and joggers to keep to the footpaths have survived and been well accepted by the general public. The Town Council at Upton on Severn in Worcestershire is also sympathetic to the idea of reducing disturbance to nesting birds on Upton Ham, and local residents have shown great interest in the birds of the Ham.
  • We have made special efforts to contact as many as possible of the farmers who farm these hay meadows and whose traditional farming methods are one of the best hopes of maintaining breeding Curlew populations.
  • We have also been quite busy with media activities: on 7 May, BBC “Countryfile” carried a short interview with MS and the Reserve Manager from the Gloucestershire Wildlife Trust’s Coombe Hill Meadows reserve; on 31 May, MS was interviewed against a background of shots direct from the cameras at Sherborne on the live ‘red button’ session of BBC “Springwatch”, which gave time to speak in greater detail on the work being done on Curlews in southern England; and on 19 June BBC “Points West” regional news included interviews with MS about Curlews at Tewkesbury and with Richard Archer about Curlews on the Somerset Levels; some of this was repeated on BBC Radio Gloucestershire the following morning.

Mike Smart: smartmike143@gmail.com       Ian Duncan: ian.duncan28@btinternet.com

Gloucestershire Invertebrates Group meeting at Upham Meadow, Twyning, 24 June 2017 

The diet of Curlews in the breeding season in inland localities is summarised by “Birds of the Western Palearctic” as ‘Omnivorous, principally invertebrates’.  In Kazakhstan 20 stomachs examined contained mainly insects, of which most were orthopterans (grasshoppers, crickets and allies), followed by beetles > flies > lepidoptera (butterflies and moths); also plant material in nine out of 20 stomachs, 25% of total weight; mainly green parts and grain.  In USSR 15 stomachs contained mainly insects, especially beetles and orthoptera, but also ants, cranefly larvae, earwigs, lepidoptera, bugs, earthworms etc.  In Estonia 16 stomachs had mainly insects of which most were beetles.  In inland Cumberland (in August-September, rather late) mainly adult and larval dor beetles and adult and larval craneflies were taken.  This diet information is likely to refer to adults.  There are no specific data about the diet of chicks but they must be omnivorous as well, basically eating anything that moves if it’s small and slow enough to catch and handle

Areas of Upham Meadow I concentrated on certainly supported a lot of orthoptera, especially Meadow Grasshoppers but also Dark Bush Crickets and Long-winged Coneheads; I found one or two Roesel’s Bush Crickets and one Slender Groundhopper.  Other GIG members might have found other species – I am not an orthoptera specialist and I was not specifically looking for them.

Other insects were also abundant in the areas I looked at.  I concentrated on places that were a bit more sheltered from the wind and so did not venture right out into the middle of the meadow, but areas of longer, slightly damper vegetation among the shorter grass between the stream/ditch, and along the edges of the ditch itself, had good numbers of flies (at least by today’s depauperate standards).  In particular the robber flies Leptogaster cylindrica and Dioctria rufipes were in quite high numbers compared with other sites I have visited in Gloucestershire.  Robber flies are predators and their abundance indicates that there must be enough of their prey (flies, small wasps etc. ranging from tiny to almost as big as the predator) to maintain their populations.  There was also quite a wide range of soldier flies (I saw seven species, others might add more; often on a GIG meeting we only see one species), and while these are not necessarily a favourite food of Curlews the diversity of species is likely to reflect a wide range of flies in general.  Again by today’s standards, butterflies were in quite good numbers (I saw ten species, of which some were quite numerous) and there was quite a wide range of hoverflies (I saw 17  species, above average for a GIG meeting, and the full list for the day is likely to include extra species).

Haymaking as it is carried out today – with machinery, over a large area in a short time – is not considered to be good for invertebrates, whose habitat is suddenly removed en bloc and at a stroke.  The numbers of adults, eggs and larvae that can survive the trauma of haymaking overwinter and emerge again the following year, are severely reduced, and some species might only persist at some sites because they are continually re-colonised from elsewhere.

Traditional haymaking with hand tools was a gentler process, took longer, probably usually left a longer sward (although it would then be grazed by livestock) and probably left more areas uncut around edges and in “difficult” places.

In addition to the lack of disturbance, which must be a crucial factor, two aspects of the management at Upham are likely to result in better conditions for invertebrates than in a standard modern hay meadow: the cutting of hay bit by bit, in strips, with an opportunity for invertebrates to escape into adjoining patches (and perhaps spread back into the cut areas later in the same season); and the very large size of this meadow, with areas of marginal land along the ditches, the Avon and the motorway, and probably elsewhere, which are likely to provide more or less permanent refuge or reservoir areas for invertebrates from which they can re-colonise when haymaking has ceased.

This is all speculative, with no quantitative supporting data, but I would be surprised if it were completely wrong.

John Phillips

Herefordshire

The truth is that I have very little to report.  Although we have identified ten sites where Curlews have been present for most or all of the season, nobody has been able to locate a nest or, in most cases, even the field where they might have been nesting. Either there is something about Herefordshire Curlews or we lack the field-craft to track the blighters down!  Personally, I have devoted much time to one of my sites but the only hint of confirmed breeding has been from one of the local farmers who reported seeing six Curlews together about a week ago.  I have not had recent reports from Lugg Meadows but it was looking good earlier in the year and they will be cutting hay shortly which may reveal something.  Ditto with Sink Green.  These latter two are our “flagship” sites.  One other site on the edge of the Black Mountains was the nearest we have got to finding a nest site and has had an established pair (seen copulating) but outcome so far unknown (but the farmer may be able to help).

That’s about it I’m afraid. I would be very interested to compare notes with other surveyors at the forthcoming Forum on their survey techniques to see how we could improve our success rate.

Chris Robinson: herefordbtorep@btinternet.com

Shropshire

You may be interested to see our Curlew Cam.  There is a link to it on our new and developing website: https://curlewcountry.org/

Update:

22 nests found: nine predated either by crows or before a full clutch of eggs laid and a fence put up; 15 chicks hatched from four nests, but seven were lost, presumed predated already.  More chicks hatching soon.

Amanda Perkins: Amanda.Perkins@shropshire.gov.uk

[P.S. from Mike Smart: do take a look at the website; the brief note above gives only a very summary account of the huge amount of work done by Mandi and Tony Cross and colleagues in their extremely comprehensive project].

Upper Thames, Oxfordshire

Every year, a selection of sites are surveyed by volunteers, using the standard breeding wader methodology.  Over time, this allows the RSPB to determine trends in the population of breeding waders on those sites.  This year 54 sites were set up to be surveyed, and we believe 47 of those surveys are on track to be completed by 8 July.  We hope to have a clear picture of the situation for Curlew later in the autumn.

In addition this spring, 24 of those sites were set up to be surveyed every week by volunteer fieldworkers plus some staff.  These surveys focused on noting location and behaviour of Curlew.  We believe 23 sites are being surveyed as planned, and some of these led to nests being identified.

Ten nests were found by RSPB staff from four areas /survey site clusters. One nest was temporarily electric fenced, following the guidelines from Natalie Meyer.  Of the ten nests, three hatched successfully by 26 June (including the fenced nest), and seven were predated or abandoned.  The latter issue appears more prominent this year than last.  In one nocturnal predation incident, an adult bird was also killed.  Re-lays have been hard to confirm/locate.

In addition to the nest fencing pilot, interventions have included signage at sites prone to disturbance, and liaison with land managers over hay cutting and predator control.

Unfortunately, the project’s ability to report fledging success with confidence is highly constrained because the majority of birds nest in floodplain meadows.  Vegetation height almost always precludes viewing chicks after they’ve left the nest, and even adult behaviour can be hard to observe.

Kirsty Brannan: Kirsty.brannan@rspb.org.uk

South Wiltshire and Salisbury Plain

The South Wiltshire area includes Salisbury Plain and the Stonehenge & Avebury World Heritage Site.

  • Total of eight pairs recorded
  • Six pairs confirmed as breeding pairs, five nests found, sixth pair seen scraping but nest not found before apparent failure i.e. birds left site
  • Two nests predated – empty nest, one in first week of incubation and one in third week
  • One nest hatched (four eggs) with young seen
  • One nest hatched (four eggs) adults present, young not seen
  • One nest seemingly hatched one egg from a clutch of four, with no evidence of the other three eggs, no adults present – presumed failed

Monitoring period of fieldwork now finished, will be surveying for fledged young from mid-July.

A couple of thoughts re fieldwork:

  • It has been a fascinating second year of fieldwork, still on the learning curve with regard to interpreting behaviour, but feel as though we are starting to understand the birds better. All fieldwork in South Wiltshire is carried out using a 4×4 vehicle with unrestricted access to areas. It would be pretty much impossible to do anything beyond basic numbers surveying on foot, the vehicle allows us to get that bit closer without disturbance, and gives height for window mounted telescopes. Nests were found by finding sitting birds, or through watching the characteristic walk of returning birds.  Four nests were found with partial clutches during the laying period, and one with a full clutch.  Eggs in all nests when full clutch completed were weighed & measured to check accuracy of the hatch date calculation formula, use of an electronic scale is key to getting good results.  A small sample but it looks as though this could be a useful information tool, especially where there are likely to be pressures around cutting dates/interventions required etc.
  • Nest finding at laying stage was fairly straightforward with both birds present, with frequent ‘sit downs’ on the eggs; this is definitely the stage when it is worth putting the effort in, around the second week of May on the Plain. By June all were sitting on full clutches with the off duty bird invariably nowhere to be seen – much more challenging at this stage.  Given that the birds seem to be nesting in pretty much the same locations as last year, this should make future fieldwork more time efficient.  Sward length in nesting areas appears to be shorter, and less dense than in other Curlew areas I’ve visited, but all in species rich grassland.  Prior to laying birds appear to feed preferentially in areas of shorter grass in close proximity to the eventual nest site.

Many thanks to Granville Pictor, my sterling buddy fieldworker in pursuit of the long-billed bird!  It’s been fun & looking forward to next year!

Philip Sheldrake: philip.sheldrake@rspb.org.uk

North Wiltshire

I write this at 4.30 a.m. on mid-summer’s day, waiting for the sun to rise.  Across the plateau at Blakehill I can once again hear the Curlew calling.  This has become more pronounced in the past two days with them also being heard late into the evening – could this mean eggs have hatched?

The pair at Blakehill has been tormented by Jackdaws and gulls throughout nesting.

Elsewhere two other sites are now known to have Curlew possibly nesting.  These are both private sites and details are sketchy, although one of our volunteers has just received an invitation to visit one of the sites specifically to look at Curlew.  Hopefully more details to come.

Neil Pullen: NeilP@wiltshirewildlife.org

New Forest

A few bullet points from the New Forest:

  • We located about 42 Curlew territories in the New Forest in 2017, which is comparable to the 40 in 2016, even though we had a lot more publicity this year. So it looks as though the dramatic population decline of two-thirds over the last couple of decades is genuine.
  • Within those territories, we located nine nests. We were able to deploy temperature loggers and accompanying controls in seven of these nests.  We have successfully got data back from five nests so far, but only two appeared to be successful, with hatching around 31 May / 1 June.
  • There was only one observation of chicks (but they were soon predated), although we did locate another nest with hatching eggs. There is no evidence that any chicks are going to reach fledging stage, but they are hard to locate in the open forest!
  • Observers reported lots of incidents of recreational disturbance, mostly relating to dog-walkers. At least two of the nests were predated early on, probably by foxes or badgers.  These two pressures seem to be the main driver of the low productivity that we see in the New Forest.
  • We finally managed to pin down a colour-ringed bird (at a site in the north of the forest) that originated in France. It was ringed in January 2016 at Moeze (Charente Maritime) and was seen twice on territory in April 2016 in the northern forest.  It was back on its French wintering grounds by 19 July 2016 and was seen there six times between August and December 2016. It was again back on territory in the forest in May 2017, and was one of the birds mentioned above that managed to get chicks out.
  • Also of interest, a Curlew was seen taking a lizard at one site…..hopefully not a Sand Lizard!

Russ Wynn:  rbw1@noc.ac.uk

Breckland

Characterised by its sandy soils and semi-continental climate, Breckland contains the UK’s largest extent of semi-natural grass heath.  This habitat supports a number of birds of conservation concern, including Eurasian Curlew.  As part of a wider PhD project, exploring the impacts of physical ground disturbance on Breckland biodiversity, we are closely monitoring Curlew across approximately 3,700 hectares of grass heath.  Because of access restrictions across part of the study site, most of our monitoring efforts have focused on a smaller area (c. 1,800 ha).  The physical disturbance treatments comprise of 117 experiment plots that differ in establishment technique, size and cultivation frequency.

By closely monitoring the Curlew population we aim to uncover:

  • the number of breeding pairs and productivity
  • timings of nest failure to help determine likely predators (using temperature sensors), and
  • whether physical ground disturbance within grass heath habitats provides an important nesting and foraging resource.

Fieldwork is ongoing, but so far we have located 22 nests from 20 breeding pairs in 2017 (interestingly one of the resident birds was colour ringed by the Wash Wader Ringing Group in 2016).  By 23 June five of the nests had successfully hatched, and at least four pairs have chicks.  Most of the breeding attempts which failed at egg stage were predated at night, which suggests that mammalian predators (most likely foxes) are the biggest culprit.  Preliminary results also suggest that the experimental ground disturbance treatments are providing a suitable nesting habitat and an important foraging resource.  The results from this study will be reported on in future papers.

Jennifer Smart: Jennifer.Smart@rspb.org.uk   Robert Hawkes: robert.hawkes@uea.ac.uk
and Helen Jones

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