Making a real difference for birds
From the British Trust for Ornithology
Ma 2015 ke y earthe o the Houf M ar s tin! e
They share our homes, yet remain mysterious: We need YOUR help to unlock their secrets Walking in a winter wonderland
Local bird clubs work together
Garden BirdWatch milestone
First results from the Winter Thrushes Survey
A successful small-scale study of Corn Buntings
We celebrate the first 20 years and look to the future
E d i to r i a l
Welcome... ...I’m not the best birdwatcher in the world – I mistake flying Woodpigeons for Sparrowhawks, get confused by Reed Warblers and Sedge Warblers when they first arrive and I’m absolutely hopeless at gulls. Every spring I am consumed by a new determination to improve my bird ID skills – “this year I’ll nail it” I tell myself. To make matters worse, I’ve just found out that I am ranked at number 25 in the BTO staff chart for the number of ‘complete lists’ added to BirdTrack in 2014 – not a great performance! These things bother me a bit because I know I could do much better if I had more time, commitment and determination. If you feel a bit like me, join me and give it another go this year. Here are some of the tools I’ll be using to help me along: firstly, I’ll be making frequent use of the BTO Bird ID video tutorials – they’re free and cover a wide range of confusion species including Mistle and Song Thrush, Willow Warbler and Chiffchaff and Common and Arctic Tern. I find a quick refresher before or after an encounter really helps me to seal my learning in. The second thing that helps me is the practice of taking part in surveys or more informal recording schemes like BirdTrack. Forcing myself to work at identifying species in order to record them accurately pushes me that bit further
with my identification skills. It also helps me to notice more about the context of my sightings and my experience is that the surrounding habitat, sounds, behaviour, time of day etc. all add up to paint a more complete picture, which makes identification easier and more memorable. Surveys can also stretch our knowledge by, for example, forcing us to look at a specific species or a specific part of a species’ lifecycle, as the House Martin Survey will do this year. If you struggle with telling House Martin from Sand Martin or Swallow, this year could be a great year to finally crack it (and there’s a video tutorial for that too, by the way!). BTO is very lucky that not all of its fantastic volunteer birdwatchers are like me but we can all contribute in our own ways to the important evidence needed to conserve our birds and wildlife. Inside you’ll find information about a range of ways in which you can play your part, whatever your experience or skill level. You’ll also find updates on recent surveys, plans for upcoming surveys and news on how survey data are being used. However you support our work, I hope you enjoy this magazine and that it inspires you to get stuck in for birds! Thank you,
Ieuan Evans Associate Director Communications – Engagement
did you know? A grand total of 224 species were recorded by volunteers doing the Breeding Bird Survey in 2013. The average number of species recorded in a square was 31, but the record went to a square in the Lune Valley, Lancashire, where 77 species were recorded! Three migrant birds which winter in the arid zone of Africa have shown significant increases between 1995 and 2012. UK Breeding Bird Survey trends for Reed Warbler have increased by 21%, Whitethroat by 35% and Redstart by 45%.
2
A Buzzard ringed as a nestling in Cumbria in 1985 reached the grand old age of 28 years, 1 month and 11 days before being found freshly dead in 2013, just 12km from where it was ringed. An Avocet ringed in a nest in 1990 was reported alive 22 years, 7 months and 23 days later in 2013. Over 3,000 volunteers contribute to the Wetland Bird Survey (WeBS) at over 2,600 sites across the UK. WeBS is the principal scheme for monitoring the UK’s wintering waterbird populations, providing an important indicator of their status and the health of wetlands.
In 2014, more than 1,000 volunteers monitored over 45,000 nesting attempts through Nest Box Challenge and the Nest Record Scheme. The Nest Record Scheme is now in its 76th year and in that time over 1.35 million nest records from 232 different species have been sent in.
BTO Volunteer Magazine | 2 015
c o n t e n ts
In this issue... pg16
pg8
pg20
pg10 Welcome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Join Ieuan in increasing your bird knowledge! Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Cover photographs: Paul Sterry: NPL/Northeastwildlife.co.uk/Luke Delve Contents: david tipling davidtipling.com/Davidklaer.com/luke delve
Recent survey round-up . . . . . . . . . . . . . . . . . . . . . 4
Woodland soundscape . . . . . . . . . . . . . . . . . . . . . . 10 Learning bird songs and calls can really help your birdwatching in habitats where visibility can be impeded.
Busman’s holiday . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Find out how BTO staff are involved in a range of demographic surveying in their own time.
A local perspective . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Butterflies and birds . . . . . . . . . . . . . . . . . . . . . . . . . 20 It’s not all about the birds as BBS surveyors contribute to national butterfly monitoring, and find out about a fabulous joint membership offer.
News on Nightingales, Woodcocks, NEWS and regional network changes.
How a group of bird clubs got together to find out more about the Corn Bunting.
Homing in on House Martins . . . . . . . . . . . . 6 2015 is the year of the House Martin Survey and we need YOUR help!
Understanding our winter visitors . . . 14 The first results of the Winter Thrushes Survey are revealed.
Home-grown science . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Going anywhere this summer? . . . . . . . . . 16 Your holiday bird records will be essential for the next European Breeding Bird Atlas.
Celebrating 20 years of Garden BirdWatch and the amazing science it has unlocked.
A new chapter for herons . . . . . . . . . . . . . . . . . 22 The Heronries Census is about to go online, marking a new phase in our longest running survey, and one that has tracked some surprising changes thoughout its history.
The British Trust For Ornithology
ISSN 0005 – 3392
Contact us BTO, The Nunnery, Thetford, Norfolk, IP24 2PU Telephone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 01842 750050 Facsimile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 01842 750030 E-mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . btonews@bto.org Website . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . www.bto.org BTO Scotland, Cottrell Building, University of Stirling, FK9 4LA Telephone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 01786 466560 Facsimile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 01786 466561 E-mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . scotinfo@bto.org BTO Cymru, Thoday Building, Deiniol Road, Bangor, Gwynedd, LL57 2UW Telephone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 01248 383285 E-mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . kelvin.jones@bto.org The BTO promotes and encourages the wider understanding, appreciation and conservation of birds. Registered Charity no. 216652 (England & Wales) no. SC039193 (Scotland)
2 015 | BTO Volunteer Magazine
Patron HRH The Duke of Edinburgh, KG, KT President Chris Packham Chairman Tony Fox Honorary Secretary Frances Hurst Honorary Treasurer John Osmond BTO Volunteer magazine JNCC — All references to JNCC in Volunteer refer to the Joint Nature Conservation Committee, which is the statutory adviser to Government on UK and international nature conservation, on behalf of the Council for Nature Conservation, Natural Resources Wales, Natural England and Scottish Natural Heritage. Editors Ieuan Evans and Su Gough Layout, design, imagesetting and typesetting O’Connor Design Consultants
Printing Reflex Litho, St Helen’s Way, Thetford, IP24 1HG BTO Membership Individual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .£34 Family . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . £44 Life . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . £850 Fellow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . £56 Family Fellow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . £66 Life Fellow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . £1400 Fellows receive Bird Study journal.
When you have finished with this magazine, pass it to a friend or recycle it.
The views expressed by the contributors to this magazine are not necessarily those of the Editor, the Council of the BTO or its committees. The Editor welcomes any articles on birds. © BTO 2015. Quotations should carry a full acknowledgement.
3
R e c e n t s u rv ey ro u n d - u p Survey update
Catching up with Nightingales Rather a lot has happened since the survey was begun back in 2012, say Greg Conway and John Marchant. Firstly, additional surveying was required in 2013 to provide adequate coverage of regions under-sampled in the first year. Extra effort was concentrated into Suffolk and Essex, where the survey workload had been especially heavy. Also, in 2013, BTO became heavily involved in providing impartial data on Nightingales in relation to the proposed Paul Sterry: NPL
Lodge Hill development in Kent, which is also the single most important site for Nightingales in Britain. Of critical importance was whether or not the site held more than 1% of the UK grand total of singing male
A preliminary population of only around 6,000 singing male Nightingales was estimated in 2012.
Nightingales since, if it did, the existing SSSI designation could be extended to provide
process but has resulted in a novel and
county population estimates, will be made
statutory protection for the Nightingales.
highly sophisticated modelling approach,
available on the survey page: www.bto.org/
The high-profile political interest and
which will set a new standard for future
nightingale-news
perceived opposing controversial moves
surveys.
Meanwhile, a preliminary estimate of
to upgrade the site designation or pursue
Two papers are in progress for 2015,
approximately 6,000 males in 2012 has
the development meant that the national
the first documenting the new population
been published on the BTO’s BirdTrends
population estimate provided by BTO had to
modelling approach and the other
web pages. This represents a sharp decline
be sufficiently robust to pass Defra scrutiny.
examining changes in abundance and
from the 1999 survey, for which population
Achieving this has been a time-consuming
distribution. Updates and outputs, including
estimates need to be revised upwards.
BTO/GWCT Woodcock survey and annual monitoring The results from 2013 have been analysed and will be published in a paper examining changes in both abundance and distribution since the 2003 survey, including a longerterm assessment of distribution change using Bird Atlas 2007–11 data. A second paper is planned, which will examine changes in habitat use and the potential influence of a
4
broader range of factors such as deer, disturbance and soil moisture levels. See www.bto.org/woodcock-survey for results and updates. Annual counts have been undertaken at around 25 sites throughout the period between the 2003 and 2013 surveys and these have highlighted the steady reduction
in breeding numbers, which is a cause for concern. In 2014, the counts continued and the number of sites was increased to 150, which will provide greater capacity for monitoring future changes. More monitoring sites are still needed, so please continue to cover your 2013 survey square, or contact Greg Conway (woodcock@bto.org) for details on how to take part.
BTO Volunteer Magazine | 2 015
R e c e n t s u rv ey ro u n d - u p Non-Estuarine Waterbird Survey
News about NEWS From Lundy to Loch Linnhe and Seahouses to Scrabster, plans for next winter’s Non-Estuarine Waterbird Survey (NEWS) are taking shape!
Changes to our Regional Network Our volunteer Regional Representatives (RRs) do a fantastic job representing BTO at the local level, organising surveys, being the point of contact for local members and volunteers, organising events and so much more. Here we thank the RRs that retired during 2014, and welcome aboard the new ones that have joined us.
Laurie Campbell: NPL
Retiring Regional Representatives Arthur Brown . . . . . . . . . . . . Argyll (N) 2009–2014 Roger Warren . . Buckinghamshire 2010–2014 Mark Eddowes . . . . Cheshire (NE) 2008–2014 Mark Eddowes . . . . . . . Cheshire (S) 2013–2014 Clive Hartley . . . . . . . . . . . . . . Cumbria 2002–2014 Alastair Flannagan . . Glamorgan (W) 2011–2014 James Gloyn . . . . . . . . . . Isle of Wight 1992–2014 Jean Roberts . . . . Lancashire (NW) 2005–2014 Steve Suttill . . . . . . . . . . . . . Manchester 2003–2014 Bob Proctor . . . . . . . . . Moray & Nairn 1994–2014 Richard Paul . . . . . . . . . . . . . . Perthshire 2005–2014 Harry Green . . . . . . . . . Worcestershire 1972–2014
Some waders, such as Turnstone, are not as frequently encountered on sandy/muddy habitat, preferring rocky shores, but results from WeBS and NEWS show that these species are in decline.
NEWS will repeat similar surveys
and passerines such as Rock Pipit,
undertaken in the winters of 2006/07,
and collect information on the tidal
1997/98 and 1984/85. Past results
wrack resource on beaches. Stretches
showed that numbers of Ringed Plover,
of non-estuarine coast will be
Sanderling, Purple Sandpiper, Bar-tailed
allocated to volunteers, and there will
Godwit and Turnstone have fallen on
be opportunities for groups of keen
the Scottish coast, contributing to UK
birders to undertake expeditions to
population declines. Many of these
important areas. We anticipate that
birds occur in internationally important
some professional fieldwork will be
numbers, yet the remote nature of
needed to fill gaps.
rocky shores and other non-estuarine
Previous NEWS surveys were
coast means it is a habitat which is
primarily funded by the UK’s Country
poorly monitored by the Wetland Bird
Agencies (nowadays: SNH, NE, NRW
Survey (WeBS). Periodic coverage by
and DOENI). Funding for this winter’s
NEWS is therefore a key part of the
survey has not yet been secured – so
UK’s waterbird monitoring programme.
we don’t yet have final confirmation
As well as the key waders, NEWS will include counts of inshore seaducks
2 015 | BTO Volunteer Magazine
that the survey can take place but we
New Regional Representatives Phil Tizzard . . . . . . . . . . . . . . . . . . . . . . Buckinghamshire Hugh Pulsford . . . . . . . . . . . . . . . . . . . . Cheshire (NE, S) Colin Gay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Cumbria Claire Young . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dorset Lyndon Jeffery . . . . . . . . . . . . . . . . . . . Glamorgan (W) Jim Baldwin . . . . . . . . . . . . . . . . . . . . . . . . . . . Isle of Wight John Clarke . . . . . . . . . . . . . . . . . . . . . . . . . . . Londonderry Nick Hilton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Manchester Melvin Morrison . . . . . . . . . . . . . . . . . . . Moray & Nairn Ken Graham . . . . . . . . . . . . . . . . . . . . . . Yorkshire (L&W) Steve Davies . . . . . . . . . . . . . . . . . . . . . . . . Worcestershire You can find out more about the Regional Network online (www.bto.org/volunteersurveys/regional-network) and make contact with your local RR. Vacant BTO Regions We have a number of BTO regions with no RR. If you are interested in taking on the role of RR, or part of the job, please contact Dawn Balmer at BTO HQ (dawn.balmer@bto.org or call her on 01842 750050). Scotland: Angus, Argyll (N), Dumfries (from July), Perthshire, Sutherland England: Essex (NE), Essex (S), Lancashire (NW), Yorkshire (SE), Yorkshire (SW) Wales: Anglesey
will update you as soon as we can.
5
H o u s e M a rt i n S u rv ey
Homing in on
House Martins Planning for BTO surveys starts well before fieldwork can take place, to ensure the survey methods are clear and interesting for our volunteers, yet also scientifically rigorous. More pragmatically, we need to ensure that we can fund any survey. Thanks to the generous donations you made in response to last autumn’s House Martin Appeal, we can go ahead with the UK House Martin Survey this year. Survey organiser Ian Woodward brings us up to speed.
on the counts at these sites. In order to use the counts to produce a population estimate, it is essential that squares are picked randomly so that they are representative of the UK as a whole. This approach is followed for many BTO surveys, including the BBS. so many of you will already be familiar with this concept.
We have been keen to run this
will be to obtain a robust population
survey for several years, particularly
estimate. There are two broad approaches
Habitat basis
after seeing the rapid and dramatic
to choose from: a census or a sample.
For single-species surveys, we
changes in House Martin populations
A census aims to carry out a full count
sometimes use a ‘stratified sample’,
and distributions documented by Bird
by visiting all sites where a species is
grouping squares into different
Atlas 2007–11. Our planning kicked off
known to occur or potentially occurs.
categories (often based on habitat), and
in earnest last summer, when we ran
This is possible for scarcer species which
select a proportion of squares from each
a small-scale pilot survey. Pilot work
are restricted by habitat requirements
category to ensure we cover all suitable
allows us to test our methods and make
to a small number of sites. However,
habitats. House Martins are most likely
decisions about what data to collect
for species with a large and scattered
to breed in small villages or close to the
and how to collect them. Our pilot
population like the House Martin, this
edge of towns, but they can also be
survey enabled us to confirm that the
approach is not possible.
found at sites ranging from dense urban
Instead, a sampling approach is
centres to isolated farmhouses, as well
adjustments to the survey methods. We
needed. A small proportion of sites
as coastal and inland cliffs. Our survey
have also been thinking carefully about
(usually squares) are surveyed and a
will therefore need to cover a wide range
exactly how we will use the data, and
population estimate is calculated, based
of habitats including some of these
survey was feasible and to make some
extremes.
how we can make use of information collected from other sources such as land-use data and satellite images. Choosing the squares Another important component of survey planning is deciding which sites to cover. The main aim of the 2015 survey
6
“Our pilot survey enabled us to confirm that the survey was feasible and to make some adjustments to the survey methods.”
This variability presents us (and our volunteers!) with a challenge – some 1-km survey squares will contain only a couple of houses and will take just a few minutes to survey, others will be entirely urban and may take several hours to cover thoroughly.
BTO Volunteer Magazine | 2 015
H o u s e M a rt i n S u rv ey
The House Martin Survey has been timed to coincide with the incubation and provisioning of the first brood. Once these have fledged, recordind can get very complicated, with juveniles returning to the nest to help with later broods.
we need your help!
achieve good coverage. You can choose
see if you can cover a square near to your
A robust population estimate from
a square by visiting our website (www.
holiday site. A single visit in June will be
random sample surveys can only be
bto.org/house-martins). If it will take only
better than no visits at all.
made if good coverage is achieved and
a few minutes to cover all of the suitable
no bias is introduced because volunteers
habitat available in your square, please
contain House Martins, occupancy is
select what they perceive to be the better-
have a look to see if you can take on a
unpredictable even in the higher-quality
quality squares. As always, we are relying
second square.
habitat, so we know there will be some
Paul Sterry: NPL
on our excellent network of volunteers to
“Whilst we expect many squares will contain House Martins, occupancy is unpredictable even in the higher quality habitat.�
2 015 | BTO Volunteer Magazine
Bias can also be introduced because
Whilst we expect many squares will
squares without any House Martins. We
there are fewer people in some parts
know how frustrating it can be to travel to
of the UK, making it harder to achieve
carry out a survey and not find the target
full coverage in these areas. We can
species. However, even if your square has
sometimes control for this sort of bias
no House Martins, these zero counts are
during our analysis, but it is better to
extremely important to produce an accurate
resolve it up-front by surveying more
population estimate, so by submitting your
squares in all regions. If you are going on
zero count you will be making a valuable
holiday in the UK in June, please check to
contribution to the survey.
7
G a r d e n B i r dWatc h
Celebrating twenty years of
science in your
gardens There have been big changes at our winter feeding stations over the last 20 years, with new species, such as Blackcap, becoming familiar sights.
8
BTO Volunteer Magazine | 2 015
G a r d e n B i r dWatc h
Gardens are often the place where people first encounter birds and other wildlife and learn to love them, says Clare Simm. In addition, gardens are an important habitat supporting a wide range of species. Back in 1995, when Garden BirdWatch (GBW) started, gardens were less appreciated, meaning that funding for garden surveys was hard to come by; so, it is thanks to our supporters that we have made it to our 20th anniversary. There were predecessors to GBW. The
Thanks to the enthusiasm of Garden
Garden Bird Feeding Survey started in 1970,
BirdWatchers, we have also been able
but due to the lack of external funding, the
to run one-off surveys to answer other
numbers of participants had to be limited.
scientific questions. The Shortest Day Survey
The BTO then managed to secure short-
was run in December 2004 to investigate
term funding for other garden surveys (BTO/
whether there is a pattern to the time at
BASF Garden Bird Survey and BTO/IWC
which different bird species arrive at garden
Garden Bird Enquiry). Eventually, with core
feeders on a winter’s morning. 5,460
funding from CJ WildBird Foods Ltd and
people participated, including a sizeable
the generosity of BTO supporters, Garden
number of Garden BirdWatchers, and it was
BirdWatch was launched and, by the end
discovered that the time at which garden
of 1995, an astonishing 5,028 people had signed up; 708 of those are still contributing
One change over the 20 years is the nowfrequent visits of Long-tailed Tits to feeders.
records to this day.
David Kjaer.com/Northeastwildlife.co.uk/davidtipling.com
For many who joined in 1995, recording
birds begin to forage on winter mornings may be limited by their visual capacity at low light intensities. It was also found that
Sadly, Garden BirdWatchers have also
birds appeared at garden feeding stations
birds for GBW seemed like a natural
charted the decline of some of our well-
later in the morning in urban areas than
progression as they were already noting
known garden bird species. While some,
in rural areas during the winter. This latter
down their garden birds. One Garden
like House Sparrow and Starling, have been
finding prompted us to run the Early Bird
BirdWatcher from Gwent told us that “as soon
declining since before the survey started,
Survey in January 2014, to investigate
as I read about GBW, I realised that it was
others, including Greenfinch, have had
whether light pollution has any effect on
exactly what I’d been waiting for – a chance
their population crashes tracked by GBW.
the foraging behaviour of garden birds. The
for my birdwatching to be of use.” Since
For Greenfinch, BTO scientists were able
results from the latter survey have just been
then he has submitted the most records
to pinpoint when the population started
submitted to a peer-reviewed scientific
from a single site, with his highlight being a
to decrease by combining GBW data with
journal for publication.
Hawfinch – the first he’d ever seen, despite
information from the Garden Bird Health
looking for it in a number of woods!
initiative. This study revealed that the disease
simple things
trichomonosis, originally known from pigeon
In the 20 years of GBW we have had
fascinating findings
species, started to affect Greenfinches
a phenomenal 481 different species
Thanks to 94.7 million species observations
in 2005 and they have been declining
recorded. One garden in Cumbria has
(from 7.3 million weekly submissions), GBW
in gardens ever since, reflecting what is
recorded 167 species, including Water
data have been used to show a variety of
happening in the wider countryside.
Shrew and Grasshopper Warbler. While
fascinating things. These include determining
seeing unexpected species is a buzz for any
seasonal patterns, such as the autumnal dip in
Garden BirdWatcher, many of them told us
Blackbird reports, how the weather can affect
that it is the simple things that keep them
garden use, such as the phenomenal rise in
hooked. One, from Gloucestershire, said “It
reports of Blackcap during the cold weather
[GBW] provides an opportunity to watch bird
in March 2013, and how garden use has
behaviour – the reaction when a Sparrowhawk
changed over the last 20 years. Goldfinches
is about, the ‘pecking’ order between species,
were reported from an average of only 12% of
the arrival of Blackcaps in winter compared
GBW gardens in 1995 but, by 2012, an average
with timings in previous years…”
of 63% of gardens had reported them. This
It is the long-term records of common
increase in garden use has been attributed
species that have allowed us to find out as
to changes in the food that we provide for
much as we have, so a huge thank you to
birds, with nyger seed and sunflower hearts becoming more common food items and much to the Goldfinches’ liking.
2 015 | BTO Volunteer Magazine
Want to know more about GBW and the birds that use your garden? Visit www.bto.org/gbw.
those who currently take part in GBW and those who have taken part in the past – your time and devotion are much appreciated.
9
B i r d I d e n t i f i c at i o n
A walk in the woods: a springtime soundscape One of the greatest birding joys is a walk through spring woodland, soaking up the sights and sounds as our birds enter the breeding season. Birdwatching in woodland can be frustrating, however, as the birds often remain resolutely hidden behind the new spring leaves. Being familiar with their songs and calls will equip you with a whole new way of both finding and recognising birds, and might help you home in on a target species. Come with Ben Darvill and Su Gough on a walk through the woods to see this in action…
As we set off through the fresh green
or ‘primary projection’, however, the simple
tits suggests otherwise and our curiosity is
morning, we are surrounded by mature
repetitive ‘chiff-chaff’ song immediately gives
rewarded with splendid views of a Lesser
broad-leaved woodland, with the sun filtering
its identity away!
Spotted Woodpecker; their raptor-like call is a
down through the new leaves. Away from
Another frequent song is the bell-like
good one to learn! We make a mental note
the path the ground is almost devoid of
ringing ‘teacher-teacher’ of Great Tit, but a
to look more closely at the foraging mixed tit
plants, but there is vegetation from shoulder
sudden sneezed ‘pit-chou’ alerts us to the
flocks which roam through these woodlands
height and upwards to the tops of the
presence of a Marsh Tit. This is the call, and
in winter – these diminutive woodpeckers
trees. Common birds are all around and will
we probably won’t hear Marsh Tits singing
have a habit of joining them.
accompany us on the whole of our walk:
today as, for them, the breeding season is
the short, sweet, melancholy phrases of
already well advanced. As we move past one
area with large conifers. The feel of the wood
Robin; the melodic, thin, metallic song of
large tree a loud ‘kek, kek’ echoes around
changes completely, as do the sounds we
the Dunnock and the fluty, rich and luscious
and we stop and wait until the Great Spotted
are hearing. The most frequent are short,
Blackbird song. Almost at once we spot a
Woodpecker moves around the trunk and
soft contact calls, but we are not confident
small warbler high in the tree tops. From this
reveals itself – a stunning male with his red
to identify these until one of the birds starts
distance and angle there is no way
nape patch. Then we realise that he has his
singing, a jaunty hop-skip ‘dee-d-lee-dee-d-
nest hole high on the same tree – the young
lee’ with a finishing flourish – confirming the
we could look at the leg colour the Visit rsion of e ve hear onlin rticle to ds n a this bird sou ! the scribed de
We carry on walking, entering into an
are calling from within. We move on, to allow the adult to feed his chicks in peace. dramatic action A thin, high ‘shree-shree-shree’ call emanates Northeastwildlife.co.uk/david tipling davidtipling.com/Andy Mason
from another trunk and we turn to scan the tree with binoculars, finally spotting the small mouse-like Treecreeper heading up the trunk. We would have missed it completely if we hadn’t heard it first! Suddenly there is a burst of very high-pitched simple ‘seeet’ whistles from the birds around us and, recognising this as the ‘avian predator alarm call’ of many small birds, we look around for the cause. We’re rewarded with the sight of a silent female Sparrowhawk flashing fast and low through the trees. Panic over, the birds return to more relaxed behaviour. Suddenly, a loud ‘kee-kee-keekee-kee-kee-kee-kee-kee-kee-kee’ call echoes Stock Dove is often over looked as a Woodpigeon, unless its distinctive song is known.
10
out, and we wonder if the Sparrowhawk has returned but the relaxed behaviour of the
Birdwatching in woodland can be frustrating, but easier if you let the songs and calls help you.
BTO Volunteer Magazine | 2 015
B i r d I d e n t i f i c at i o n
How to tune in… If you’ve been inspired to improve your knowledge of bird songs and calls, here are some top tips. Access the online version of this article and listen to the songs and calls that we’ve featured. Visit www.bto.org/woodland-song. Invest in an audio-guide which is optimised for learning. Geoff Sample’s Bird Songs and Calls is recommended. The 3-CD set takes you through different habitats, allowing you time to try identifying each species before the narration gives you the right answer. Test yourself. Why not stop for a minute when you’re out on a walk and actively listen. You could even shut your eyes. Try and identify everything that you can hear, then use your binoculars to search out those species that you were uncertain about.
Learning songs and calls can help your birding in numerous ways, including enabling you to go into an area armed with another way of locating and identifying a target species, such as the scarce and elusive as Lesser Spotted Woodpecker.
birds as Goldcrests. We hear ‘teacher-teacher’ again, but this time the song lacks the strength and bell-like ringing quality heard earlier, instead sounding weaker, reedy and slurred, identifying the bird as a Coal Tit this time, the difference in quality of song being the clincher. helping to target We move out into a more open shrubby area,
Make up your own mnemonics - you’re more likely to remember yours than other people’s. For example, Ben remembers Chaffinch song as ‘ha ha ha ha, ha ha ha ha, ha ha ha! I shot you!’ It works for him!
“There is a different warbler singing from the shrubs in our wood – a beautiful, complex, rich and fluty song. The big question – is it a Blackcap or Garden Warbler?”
The bird does not reveal itself, however, so there’s still a little doubt in our minds. A maniacal laughing call is much easier to identify: a Green Woodpecker ‘yaffling’ and, as we walk around the corner into a grassy clearing, we interrupt its Wood Ant meal and it bounds away up into the trees. We are back in broad-leaved woodland now, and a large bird passes overhead, silhouetted against the sky.
As we walk into the more open area
It calls, a cat-like mewing: a Buzzard. Just as
edge of the conifer patch and it’s in this area
there are piles of brash lying around and a
we leave the wood, a low distinctive ‘whoo-
that we hope to catch up with one of our
machine-gun-like song resounds from low
whoo-whoo’ draws our attention to a pair of
target species. A few moments scanning the
down in these piles. It’s a Wren – one of
Stock Dove perched in one of the larger trees
trees for movement produces nothing. Then
the loudest birds for the size of its body.
– we could easily have missed them amongst
we hear another Goldcrest singing. But wait!
There is a different warbler singing from the
all of the Woodpigeons, if their song wasn’t so
Is it a Goldcrest? The song is similar (it’s clear
shrubs in our wood – a beautiful, complex,
distinctive.
and high-pitched), but it lacks the jaunty hop-
rich and fluty song. The big question – is
skip notes, sounding more like an accelerating
it a Blackcap or Garden Warbler? A difficult
our ability to identify at least some of the
‘dee-dee-dee-dee-dee-dee’ with a less
one this, but the bird in front of us is singing
species we heard by sound. You never stop
flamboyant finish. Finally we see movement
with a steady pace and the ‘verses’ seem
learning, however, and this is one of the joys
low down and watch through binoculars as a
well-practised and not over-long. Each phrase
of discovering bird songs and calls, there are
beautiful male Firecrest emerges briefly but,
seems to start tentatively but finish in a rich
always new species, new sounds and even
thankfully, for long enough to see the face
and confident manner. We are pretty certain,
familiar species making a sound you have
stripes and chestnut shoulder patch. Excellent!
therefore, that we are listening to a Blackcap.
not encountered before.
but there is a stand of Douglas Firs on the
2 015 | BTO Volunteer Magazine
A great walk, which was enhanced by
11
F o c u s o n Vo lu n t e e r s
focusing in on the details
Corn Buntings: a local perspective
Recent years of atlas fieldwork uncovered many birdwatchers who had not previously participated in surveys and were keen to contribute to our understanding of changing bird populations. Chris Dee, BTO Regional Representative for Hertfordshire, describes how three neighbouring bird clubs collaborated to harness this untapped potential for a Corn Bunting Survey in 2014. 12
The Herts Bird Club has a long history of
in the distribution of Corn Buntings of
monitoring breeding Corn Buntings and so
between 27% and 62% over the past
welcomed the opportunity to work together
20 years – but these projects were not
with the Bedfordshire and Cambridgeshire
designed to measure population size in the
Bird Clubs to design and run a survey of
way that a targeted survey could. The atlas
the species. With plenty of enthusiastic local
fieldwork however did provide useful clues
volunteers, this was a good opportunity
about where to focus our volunteer effort.
to provide interest for local birdwatchers
By randomly selecting a fifth of the tetrads
and contribute some useful information
(2-km x 2-km squares) where birds had
about this enigmatic species in one of its
been located in recent breeding seasons,
strongholds in eastern England.
surveyors could have a reasonable degree
Results from recent tetrad-scale atlases
of confidence that they would find the target
in the three counties identified reductions
species. Data from the previous atlas period
BTO Volunteer Magazine | 2 015
Luke delve
Corn Buntings are declining in range but in favoured locations can still be found at high densities. Joining in a local bird club survey can help us to understand more at a fine scale.
F o c u s o n Vo lu n t e e r s
“There was a very positive response from local birdwatchers; 91% of the priority tetrads were surveyed and a further 66 extra squares were also visited.”
Working together locally
(1988–92) were also used to provide a smaller sample of tetrads (10%) from which birds had recently disappeared. The aim was to cover 146 tetrads across the three counties whilst giving the more enthusiastic volunteers the flexibility to take on extra squares. We built a website to show the survey squares and provide printable survey forms and the survey was publicised through the bird clubs’ websites and at meetings. Advice on survey timing was sought from Rosemary Setchfield who has been working on Corn Buntings in north Hertfordshire with the RSPB. We asked volunteers to visit their chosen locations on two occasions; once in the first three weeks of June and once in the first three weeks of July, plotting the position of all Corn Buntings on the maps provided. There was a very positive response from local birdwatchers; 91% of the priority tetrads were surveyed and a further 66 extra squares were also visited. Analysis is currently under way, with the hope that the results can help to identify population hotspots that could be targeted for agri-
The Three Counties Breeding Corn Bunting Survey is an excellent example of local bird clubs working together to discover more about a species with the aim of establishing the population size, which may well lead to local conservation action. Although the BTO is able to organise periodic UK single-species surveys in addition to our core monitoring schemes, there is still much that can be learnt through local co-ordinated fieldwork. The most recent published assessment of population estimates of birds in the UK highlighted many opportunities for volunteers to make a significant contribution to our knowledge. The report identified a suite of species for which better local population density estimates would greatly aid the difficult task of estimating population size. Examples of species suitable for small-scale local studies
include: Breeding ducks such as Mandarin, Gadwall, Teal, Eider, Red-breasted Merganser, Goosander. Breeding waders, especially in the uplands. Breeding owls and birds of prey such as Little Owl, Tawny Owl, Hobby, Kestrel. Breeding Water Rail, Rock Pipit, Kingfisher, Sand Martin, Black Redstart, Willow Tit, Lesser Spotted Woodpecker. Widespread wintering species such as Yellowhammer, Water Pipit. Wintering waterbirds in the wider countryside such as Mallard, Moorhen. If you’re interested in co-ordinating a local small-scale study and would like some advice on methodology, BTO would be keen to support you. Please contact Dawn Balmer (dawn.balmer@bto.org).
environment advice.
Tips for running a local survey… Identify a species that local atlas work has shown to be in decline or a county BAP species, but not one that is so scarce that volunteers are unlikely to find it. Investigate collaborations with other local bird groups. Decide on survey methods and sampling strategy, consulting with experts or published literature. Decide what will be counted, when and in what size survey areas.
2 015 | BTO Volunteer Magazine
Select areas to be surveyed; random sample, stratified random sample based on prior distribution knowledge or habitat features, or a complete survey of the entire area. Tailor this based on an estimate of how many birdwatchers may participate. Determine a way to allocate survey plots to observers to avoid duplication of effort, through local organisers or a
website or web page. Publicise the survey through local bird club websites, meetings, newsletters and social media. Distribute instructions and survey forms in good time. Provide feedback at the end of the fieldwork season. Write up the results for local bird report or even a national journal.
13
W i n t e r T h ru s h e s S u rv ey
Winter Visitors
Fieldfare
Thousands of thrushes migrate to the UK from mainland Europe to take advantage of our relatively mild winter conditions. But precisely how many come, how they are distributed around the UK, and what they feed on whilst they are here is not well known. The Winter Thrushes Survey was designed with these questions in mind and ecologist Kathryn Ross has been delving into the data.
The survey ran over two winters
The survey data are being used to
number of thrushes present in the UK at
(2012/13 and 2013/14), and data were
investigate two key questions, both still in
collected by 1,957 BTO volunteers from
progress:
this time of year. Investigating between-species and
Determining a population estimate
more than 4,000 unique 1-km squares
geographical differences in the use of
within the UK. Many surveyors visited their
for winter thrushes in the UK, using count
foraging habitat and food preferences
squares multiple times throughout winter,
data from ‘core squares’ that were surveyed
throughout the two winters, to help identify
providing vital information on how the
between December 27 and January 10. The
key resources and potential factors in the
habitat usage and food preference varied
abundance data collected during this core
patterns of change observed in numbers of
through the winter months.
period will give us an estimate of the total
breeding and wintering thrushes.
Fig 1 Foraging habitat preferences for the five winter thrush species Blackbird Blackbird
Foraging habitat preference in each month Fieldfare Fieldfare
Mistle MistleThrush Thrush
Redwing Redwing
Habitat Key
Song Thrush Song Thrush
Habitat
OCT Oct NOV Nov DEC Dec JAN Jan FEB Feb MAR Mar APR Apr
Woodland Woodland 0.75
1.00 1.00
0.50
0.75
0.25
0.50
0.00
0.25
0.75
0.00 1.00 1.00
0.50
0.75
0.50
0.00
0.25 0.25
0.75
0.00 1.00 1.00
0.50
0.75
0.50
0.00
0.25 0.25
0.75
0.00 1.00 1.00
0.50
0.75
0.50
0.00
0.25 0.25
0.75
0.00 1.00 1.00
0.50
0.75
0.50
0.00
0.25 0.25
0.00 14
Proportion of observations Proportion of observations
Data from the 2012/13 and 2013/14 winters were combined to show the proportion of foraging observations occurring in each habitat each month.
BTO Volunteer Magazine | 2 015
Northeastwildlife.co.uk
Amenity land Amenity land Brownfield/ Brownfield/industr industrial Coastal habitats habitats Coastal Cropped Cropped farmland farmland Moorland/heath Moorland/heath Open parkland Open parkland Orchard Orchard Pastoral land Pastoral land PrivatePrivate gardens gardens
SEP Sep
W i n t e r T h ru s h e s S u rv ey
Mistle Thrush
Where do thrushes feed? So far, we have found that the habitats
Conservation of thrushes
used for foraging vary between species and throughout the winter (Fig 1). For Redwing and Fieldfare, pastoral land increases in importance as the winter progresses. Fieldfare were more reliant on pastoral land and cropped farmland than other species, and this habitat specificity was even more pronounced in the spring months. In contrast, for Song Thrush, Mistle Thrush and Blackbird (which are back on territories and starting to breed by March in the UK), use of pastoral land appears to lessen in April. Blackbird showed less variation in habitat preference throughout the survey period compared with the other species, with private gardens, woodland and amenity land remaining important throughout the winter period. The geographical variation in these habitat preferences is still being investigated. Acknowledgements The Winter Thrushes Survey was funded by members and volunteers through the BTO Raffles in 2011/12 and 2012/13Â and generous donations from charitable trusts: The Benham Charitable Settlement/The Mitchell Trust/Keith Ewart Charitable Trust/The Saxham Trust/The Harris Charitable Trust/Marjorie Coote Animal Charity Trust
2 015 | BTO Volunteer Magazine
Breeding populations of thrushes in the UK are significantly lower than they were in the 1970s, although the trajectory of change has varied between species. Blackbird and Song Thrush numbers declined steeply throughout the 1970s and 1980s, levelled off in the mid-1990s with a period of increase between 1995 and 2005; but a downward trend has again been observed in more recent years. Mistle Thrush, on the other hand, has declined steadily since the 1970s, with no indication of levelling off. The reasons for these declines are not well understood but reduced survival of first-year birds and shifting of populations due to climate change may play a role. While Fieldfare and Redwing are ‘red listed’ in the UK according to the Birds of Conservation Concern criteria, this is on the basis of changes in our very small breeding populations of these species, so it tells us nothing about the much larger
European populations that breed on the Continent and visit the UK in the winter. According to the Pan-European Common Bird Monitoring Scheme (PECBMS) data, Redwing populations throughout Europe are relatively stable, but Fieldfare has suffered a moderate decline in the last two decades. Song Thrush is on the UK red list due to its declining breeding populations, while Mistle Thrush is currently amber listed and continuing to decline. For these species, where there is considerable overlap between the UK breeding and wintering populations, changes in winter survival are likely to impact the breeding population numbers. The more informed we are about foraging habitat, food preferences, and the availability of these resources throughout the winter, the more we can do to ensure that the right sort of habitat and resources are available at the right time of year to sustain our winter thrushes.
15
B i r d r e c o r d i n g i n E u ro pe
The new European Breeding Bird Atlas The European Bird Census Council (EBCC) has embarked on an ambitious new project to produce the second European Breeding Bird Atlas (EBBA2), reports David Noble. The original ground-breaking book, organised by the EBCC and edited by Ward Hagemeijer and Mike Blair was published in 1997 and collated information from birdwatchers in order to map the distributions of all of Europe’s breeding birds.
Submit any non-standardised bird records (akin to roving records) which must include the date, geographical location, name and contact details of the observer and any evidence of breeding. Lists of all species seen in a 50 x50-km grid, or smaller area, are also extremely valuable. Do a standardised or timed survey.
This first atlas has proved a powerful
available online in a valuable resource for
Methods for these vary between countries
tool for conservation, for identifying
future research and conservation action.
and observers are recommended to contact
hotspots, addressing the impact of
As you can imagine, there are huge
national co-ordinators in priority countries
changes in climate and land-use and for
logistical challenges, particularly in
(available on the EBCC website www.ebcc.
assessing the effectiveness of conservation
achieving coverage where there are very
info/index.php?ID=545). Where this is not
action. New data are now needed to
few birdwatchers. One of the most valuable
possible, the best option is a complete species
address emerging conservation issues, and
legacies of the first atlas was increased
list from a timed (1–2 hour) visit to a specified
birds have proved themselves very useful
co-operation across the European
geographical unit, such as 1 x 1-km, 2 x 2-km,
proxies for biodiversity more broadly.
ornithological community. This has
or a route.
EBBA2 will:
strengthened since, with new conservation and birdwatching organisations in countries
One of the easiest ways to contribute
distribution maps for all breeding species
in the east and south of the continent
records is to use BirdTrack. This free system
in Europe.
and the development of common bird
now allows users to submit data from
monitoring programmes in countries from
anywhere in the world. All breeding bird
Poland to Bulgaria.
data submitted via BirdTrack will be made
Provide better, more accurate up-to-date
Show patterns of relative abundance at a European level for the first time.
available to EBBA2 and national atlases, as
Show changes in species distributions since the last atlas.
What can you do to help?
will data from most of Europe’s other online
Build capacity for conservation and
All UK bird records (particularly those with
bird-recording systems. Otherwise, roving
monitoring in areas of Europe where this
breeding evidence) collected by schemes
records or species lists from timed visits can
is most needed.
such as BirdTrack, NRS, the Ringing Scheme,
simply be sent in a spreadsheet to national
BBS, periodic surveys and the Rare Breeding
co-ordinators or directly to the EBCC.
The project is led by the EBCC and its
Birds Panel will be used and extremely
partner organisations and the geographical
valuable.
Here’s your chance to get an atlasing fix, explore exciting parts of the continent, see
scope encompasses all of Europe including
However, you can also help if you
great birds and help a vital project at the same
Turkey and European Russia. The extended
are outside of Britain and Ireland. Every
time. Advice for travelling birders is available at
geographical scope brings exciting new
spring and summer thousands of UK
the EBCC website and 19 countries in eastern
species such as Brown Fish Owl and
birdwatchers spread out across Europe
and south-eastern Europe have appealed
Grey-necked Bunting to a list that currently
in search of sun, new experiences and
for particular help. National co-ordinators for
extends to 582 native and 63 non-native
exciting birds. Whether grabbing an hour
these countries would be delighted to hear
species. The focal period for data collection
or two around a Mediterranean salt-pan or
from observers, from groups and from tour
is 2013–17 and, at a minimum, data will be
exploring high Caucasian peaks in search
operators who are interested in contributing.
needed for each 50-km x50-km square for
of Great Rosefinches, all birders abroad
We have already seen special expeditions
comparison with the last atlas. The new atlas
can help.
by German birders to Albania, Czechs to
will ultimately be presented in a book and will embrace the new digital world, making interactive maps and additional material
16
As with Bird Atlas 2007–11, there are two main ways to contribute:
Macedonia and Moldova, and Catalonians to Montenegro and Turkey: what can the Brits contribute?
BTO Volunteer Magazine | 2 015
B i r d r e c o r d i n g i n E u ro pe White-throated Robin
Slender-billed Gull
Kentish Plover
Purple Gallinule
Black Wheatear
Cretzschmar’s Bunting
fan-tailed warbler
Ortolan
luke delve/davidkjaer.com
Sardinian Warbler
Birding in Europe is hugely popular, with a wide range of species present. If you visit anywhere in Europe over the next few years your records will be valuable for the second European Breeding Bird Atlas. Put your records into BirdTrack and remember breeding evidence.
2 015 | BTO Volunteer Magazine
17
L i f e c yc l e
Demography
on the doorstep
There may be snow on the ground as Ruth Walker and Dave Leech write, but many species are already gearing up for the breeding season. Dunnocks and Song Thrushes have been in good voice for some weeks, with Great Tits a recent recruit to the chorus. And as the birds start to stir, so too do BTO volunteers…
…including many staff members, for the allure of the field is greatly exacerbated by the day job; there’s no better incentive to get out and collect data than amazing volunteers telling you about their fantastic projects all day. Of the 113 current BTO employees, 44% are either qualified or trainee ringers, so the capacity for demographic monitoring of populations is considerable and the birds of Breckland provide an excellent weekend focus. The original aim of the Ringing Scheme was to explore movements of birds and, while advances in tagging have greatly increased our knowledge of migration routes and destinations, the fitting of metal rings still constitutes a valuable tool for studying dispersal. However, the principal use of ringing data in the 21st century is to estimate survival rates which, in conjunction with productivity (NRS www.bto.org/nrs), help to identify the causes of population increases and declines. The less things change Interpreting ringing data is much more straightforward if the effort invested doesn’t vary over time, as surviving birds have the same chance of being detected from one year to the next. Changes in the numbers handled also become meaningful indicators of abundance and breeding success rather than simply reflecting hours in the field. This is the ethos behind the Constant Effort Site (CES www.bto.org/ces) scheme, where the same mist nets are erected in the same places at the same times each year.
18
Justin Walker/steven round stevenround-birdphotography.com/Niall Burton
data provided by the Nest Record Scheme
1 BTO Volunteer Magazine | 2 015
L i f e c yc l e
The Breckland region is littered with
in Thetford, focusing on Blackbirds
staff-operated CES, the longest-running being
and Woodpigeons/Collared Doves
Peter Lack’s site at Lackford Lakes, initiated in
respectively. Incredibly, Allison’s project
1995. Stephen Baillie’s site at Redgrave and
has demonstrated that over 100 breeding
Lopham Fen followed in 1997, with the BTO
adults visit their small suburban garden in
Nunnery reserve two years later. Hinderclay
a single breeding season. Lee also leads
Fen and Cranwich gravel pits were both added
on a study of Greylag and Canada Geese
to the list in the last decade. Given these are
in the town, the birds having been fitted
predominantly wet scrub and reedbed sites, it’s
with neck collars, clearly visible even
no surprise that a lot of Reed Warbler data are
when they are on the water; while many
collected, but good numbers of other migrant
hang around on site throughout the year,
(Chiffchaff, Blackcap, Garden Warbler) and
others prefer to wander, a few moving as
resident songbirds (Blue Tit, Wren, Dunnock)
far as the North Norfolk coast.
are also encountered.
2 1. Reed Warbler is the most commonly encountered species across Breckland CES sites. At Cranwich, birds are also fitted with colour-rings to allow identification at the nest. 2. Ringing of Siskins in Thetford Forest throughout the year is providing valuable data on moult strategies. 3. Staff member Niall Burton monitors over 20 Tree Pipit nests each year for his long-term study of this declining species.
Nests as well as nets Have we met before?
16% of BTO staff also contribute to NRS.
Using mist nets to sample bird populations
Reedbed species are the staple of Dave’s
purely by chance interception, as on CES,
Cranwich project, with Reed Warblers the
works only for some species (generally
stars and Reed Bunting, Moorhen and
smaller ones) in some habitats (generally
Coot the supporting cast. More challenging
those with taller vegetation). Retrapping
is Niall Burton’s long-term volunteer study
Adults for Survival (RAS www.bto.org/
on Tree Pipit, one of the nation’s wariest
ras) projects often employ colour-rings,
species at the nest, a particular issue given
enabling birds to be identified individually
the absence of cover for the observer
from a distance and their progress
on the birds’ favoured clear-fell habitat.
followed. Colour-rings must be easily
Not to be outdone, Ian Henderson and
viewed if sufficient data are to be collected
Greg Conway scour the same patches for
and this technique can be particularly
Nightjar nests, a barely perceptible scrape
effective in towns, where birds are close
at which activity is limited to the hours
and habituated to people, as Allison Kew
of darkness! All nestlings found as part
and Lee Barber have both demonstrated
of these projects are ringed, making any re-encounter particularly valuable as their
3
exact age and origin are known. A year-round pursuit Fieldwork doesn’t end with the summer, either. Greg, Allison, Lee and Graham Austin are all involved with projects exploring annual variation in moult behaviour, primarily of finches, which necessitate catching birds in autumn and winter between Thetford and Brandon; exchange of birds between their sites also provides information on foraging ranges and strategies. Things are about to get busy and our demographic volunteers are on tenterhooks. Will bird numbers be up after a productive breeding season? Will this cold snap delay breeding? We look forward to comparing notes over the coming months!
2 015 | BTO Volunteer Magazine
19
Wo r k i n g i n pa rt n e r s h i p s
The butterflies and Since 2009, BTO, Centre for Ecology and Hydrology (CEH) and Butterfly Conservation (BC) have been working in partnership to monitor butterfly species across the UK. In 2014, 700 volunteers contributed to the survey, covering 831 randomly allocated 1-km squares. Of these squares, 44% were surveyed by BBS volunteers on BBS squares. BBS Organiser Sarah Harris says “Thank you!” and updates us on recent results.
2
Some of our BBS volunteers carry out their
of the scale, Adonis Blue, Brown Hairstreak
Research using these data at a 1-km
BBS surveys for birds as normal and then
and Purple Emperor were recorded just once,
square scale focused on the abundance
revisit the square a minimum of twice more
a rare treat for some BBS volunteers. There
and community structure in birds and
in July and August to record the butterflies
is also the option of recording moths and
butterflies on BBS squares, as well as
for the Wider Countryside Butterfly Survey
dragonflies during the WCBS visit: the most
looking at this in relation to habitat and
(WCBS).
widespread moth was the Six-spot Burnet
latitudinal data. From this information, the following
Looking at the 2014 WCBS data from
and, living up to its name, the Common
BBS squares alone, Meadow Browns were
Darter dragonfly was seen on the highest
community measures can be assessed:
recorded in the highest number of squares –
number of BBS squares.
Species richness – total number of
253 of the 362 BBS squares surveyed – and
But what has the WCBS carried out on
species recorded in each visit;
were also at the top of the table for having
BBS squares told us about the birds and
Evenness – how different the abundances
the highest abundance. On the other end
the…butterflies? We often hear how ‘birds
of species within a community are from
are good indicators of
one another. Evenness is highest when
environmental change’;
a community is not dominated by a few,
the assumption is
highly abundant species or when all
that if well-monitored
species have an equal abundance;
species are increasing,
Diversity – the function of both species
declining or stable, in
richness and evenness;
a given community
Specialisation – separating the
structure, other
generalist species from the specialists.
unmonitored taxa will
Generalists can thrive in a wider range of
be doing the same.
conditions or have a more varied diet than
Past research suggests
specialists who require a more specific
this assumption is
habitat or food source.
1
strongest at the larger
20
At a fine scale, bird and butterfly
scales. What about
richness, diversity and specialisation
when we look at
displayed the same trends. In these cases
the finer scale? Cue
the assumption that if well-monitored
BBS and WCBS data!
species are increasing, declining or stable,
BTO Volunteer Magazine | 2 015
work together:
the Birds
In celebration of our work together:
JOIN 2-for-1 JOIN
2-for-1
3 in a given community structure, other unmonitored taxa will be doing the same does apply. At a large scale, latitude and habitat type did affect the community measures but, for richness and diversity, the relationship between
1. Meadow Brown This widespread and common butterfly topped the list of most frequently enountered species during WCBS surveys.
Butterfly Conservation AND BTO membership Butterfly Conservation for just £30
AND BTO membership With a single payment to for just £30 www.bto.org/birdsandbutterflies
or by calling 01842 750050 you will receiveWith TWOa single memberships payment for to www.bto.org/birdsandbutterflies the remainder of the year with all the or by calling 01842 750050 benefits each offers you will receive TWO memberships for the remainder of the year with all the benefits each offers
birds and butterflies remained strong. The assumption that population trends of well-monitored species will be reflected in other taxa is supported for common and widespread species but not for rare and specialised ones. Conservation responses for priority species are, therefore, unlikely to benefit other species of conservation
Northeastwildlife.co.uk/Luke delve/david tipling davidtipling.com
concern, unless their declines have common causes. This study suggests applying this principle at a finer scale to assist with understanding the drivers of biodiversity change, informing landowners and conservation at individual sites. Finally, thank you to all the fantastic BBS Regional Organisers who manage the survey locally and to the BBS volunteers themselves. To find out more about the BBS or adding the Wider
2. Swallowtail is a scarce and localised species in England, but occurred on one WCBS square. Unfortunately, the number of squares countrywide was still not high enough to pick up the influx of European Swallowtails on the south coast.
Offer available for available for new newOffer members of each membersonly of each organisation andorganicloses on sation only and closes on 31 31May May2015. 2015. After 31 December After 31 December 2015 2015you youwill willbe beasked asked independently independently bybyboth although bothcharities charitiesto to renew renew although thereisisno noobligation obligation to do so. there so.
3. BBS Volunteer Taking on a WCBS square on your BBS square is a possibility, and 360 BBS surveyors chose to make return summer visits to their squares for this reason.
Countryside Butterfly Survey to your BBS square, please visit www.bto.org/bbs, or contact us at bbs@bto.org.
BTO Registered Charity no. 216652 (England & Wales) no. SC039193 (Scotland). Butterfly Conservation Registered Charity 254937 Charity (Englandno. & 216652 Wales) no. SC039268 (Scotland) BTO no. Registered (England & Wales) no.
SC039193 (Scotland). Butterfly Conservation Registered Charity no. 254937 (England & Wales) no. SC039268 (Scotland)
2 015 | BTO Volunteer Magazine
Butterfly Conservation_Vol_ad.indd 1
21
03/03/2015 14:30:03
C o lo n i a l Wat e r b i r d s
Heronries Census goes online When observers for the first national survey of heronries posted their nest counts to Max Nicholson back in 1928 they could hardly have imagined that the survey would become an annual one and, nearly ninety years later, be entering another exciting new phase. John Marchant reports.
In the 1930s only a few dozen people made
Little Egrets were UK rarities until the 1980s
Census counters. Spoonbill, Cattle Egret and
annual counts but the Heronries Census has
and unrecorded as breeders until 1996!
feral Night-herons have also nested among
grown in popularity and now covers at least
Since then they have become widespread
Grey Herons and been counted for the
60% of all UK heronries each year. Except
residents with a rapidly growing population.
survey and around 10% of inland Cormorant
for the periodic ‘Heronries Surveys’, in which
Most joined in with existing colonies of Grey
colonies are at sites also occupied by Grey
special efforts were made to count heronries
Herons and have been reported by Heronries
Herons. Coverage of all these colonial
nationwide, the survey kept a relatively low profile throughout its early history – operating
700 700
early 1990s and the Heronries Census emerged
600 600
as a full member of the BTO’s family of annual
500 500
300 300
enables monitoring of Grey Heron populations
200 200
not just for the UK but also for the three British
100 100
concept of the Heronries Census as a singlespecies survey: it’s hard to contemplate that
22
2012 2012
2008 2008
2004 2004
2000 2000
1996 1996
1992 1992
1988 1988
1984 1984
1980 1980
1976 1976
1972 1972
1968 1968
1964 1964
developments put paid to the original
00
1960 1960
In parallel, extraordinary avian
1956 1956
countries separately, with ever-greater precision.
1952 1952
especially in Northern Ireland and Scotland, now
400 400
1948 1948
regional network. Growing volunteer support,
1944 1944
monitoring surveys, organised through our
1940 1940
BTO resumed allocating staff time to it in the
800 800
1936 1936
for many years by expert volunteers.
900 900
1932 1932
data from relatively few counters, marshalled
1928 1928
mainly in England and Wales and receiving
FIG 1. Number of heronries counted. Coverage of UK heronries has increased greatly, boosted by periodic ‘Heronries Surveys’, in which special efforts were made to count heronries nationwide.
BTO Volunteer Magazine | 2 015
C o lo n i a l Wat e r b i r d s
FIG 2. Data are entered for each visit separately, along with the ‘year’s best estimate’ (YBE) of apparently occupied nests of each of the species.
FIG 3. Observers are encouraged to record the location and extent of colonies at fine scale. They can provide one or more editable polygons that relate to a particular year.
but are the product of data collection
explicit data entries of zero, which are not
across a whole breeding season. Sites are
recorded for other BTO online surveys.
david tipling davidtipling.com
chosen not randomly (as in BBS) nor by observers (WeBS, BirdTrack) but by the birds
Heronries online
themselves. Especially in forestry, nesting
The pages for the online survey are not fully
areas can shift over time, while remaining
realised as I write but are due for launch in April.
recognisably the same colony. Outrageously, it
Some previews are presented above.
is still the case that some of the nesting sites
The 2015 Heronries Census season has
herons choose are vulnerable to persecution:
started as normal, with Regional Organisers
access to lists of heronry locations therefore
distributing cards to observers. Counts can
needs to be restricted. On the other hand,
be returned in any format but we are hoping
we wish to open the survey more widely
for a strong take-up of the online system.
waterbirds has become integral to the
to members of the public, who might have
Data that reach us in the post or by email
survey’s role. Should ibises start to nest, they
access to land holding heronries as yet
will be input online. There is no intention to
would be covered by the Heronries Census,
unknown to the survey or could provide
phase out the cards – of which a new batch
but bitterns, Purple Heron and Great White
valuable help with the early reporting of newly
has just been printed!
Egret, that mostly nest singly, are not.
established heronries.
This year’s heron nesting season is already well under way. Soon, the Heronries Census will be receiving its first online submissions.
Online data input and data access, long
These difficulties have been overcome
Broadening the scope
familiar to supporters of our better-funded
by introducing features new to BTO online
There is much overlap between survey
surveys, has however not been available
survey design, such as a more versatile
requirements for herons and for other
for the Heronries Census. We are happy to
mapping tool and a new way for Regional
birds that nest in colonies. For this reason,
announce that, thanks to a generous legacy,
Organisers to allocate sites. While visit
the Heronries Census, with its range of
in 2015 the Heronries Census joins the BTO’s
observations are entered against a date and
‘heronry’ species, is presented online as
array of online options.
time, as in other surveys, the key value for
the first and currently only module under
population monitoring – the ‘year’s best
a new, exploratory concept – the Colonial
Modelling HC data
estimate’ (YBE) – is recorded independently
Birds Recording Scheme. Thus, where
Despite the expertise of our Information
against the season as a whole. The YBE
BTO can find the necessary resources, the
Systems department in this area, designing a
defaults to the year’s highest (or only) count
field is open to add new modules under
database for an online Heronries Census has
or estimate of apparently occupied nests but
this umbrella over the years ahead where
presented a number of new challenges. There
the observer can override this, for example
observers can enter counts and YBE-style
are several reasons why approaches needed
if different nests in the colony had been
data for apparently occupied nests of other
to differ from our other online surveys.
counted on different days. The survey’s
colonial birds such as Rooks, martins, and
Regional Organisers will verify or query dated
seabirds, at home or even abroad.
Unlike all our previous online surveys,
After exceptional periods of incubation
the Heronries Census’s primary data –
counts and can adjust each species’ YBE, for
counts of nests by colony and season – do
example where additional observers have
and growth, the fledgling Heronries Census
not relate to any particular date and time,
supplied data for the same site. YBE requires
is starting to take flight!
2 015 | BTO Volunteer Magazine
23
Binoculars & Telescopes Verano BGA HD
Discovery WP PC
100% made in Japan and featuring an HD optical system for sensational images and superb colour contrast, the Verano BGA HD guarantees you the highest levels of comfort and performance whenever and wherever you use them.
Using an ultra-compact optical design the Discovery WP PC series are among the smallest waterproof roof prism binoculars available on the market. 5 year guarantee.
Recommended by
Features include class leading fields of view with or without glasses, close focus to 2m and a comprehensive 30 year guarantee for peace of mind. 8x32 £429, 8x42 £439, 10x42 £449
Specially designed for adults and children 7 years+, 2014 Discovery’s fold to 52mm (8x32), 53mm (8/10x42) 8x32 £169, 8x42 £179, 10x42 £189
Digiscoping Kits
MM3 GA ED
Affordable and easy-to-use these digiscoping kits include an Olympus VG-180 camera plus all the mounts needed to fix it to compatible HR2, HDF T or SDL eyepieces. £189
A new level of performance for less than you might think, the MM3 GA ED are the latest evolution of the travelscope concept pioneered by us nearly 20 years ago.
Phonescoping Adapters Opticron smartphone photoadapters are a convenient and inexpensive way of attaching your smartphone to your Opticron spottingscope eyepiece and shooting high magnification photos and video. Available for iPhone 4/4S, 5/5S, Samsung Galaxy S3/S4. Prices from £39.95
At 600g (50mm) / 730g (60mm) without eyepiece an MM3 GA ED weighs around the same as pair of 42mm binoculars and can be used without a support for crystal clear flat field observation at magnifications below 20x. Unlike binoculars, an MM3 GA ED continues to deliver stunning clarity and definition up to 36x (50mm) and 45x (60mm). Available in straight or 45˚ angled bodies with a choice of interchangeable eyepieces including HDF and SDL. Bodies: MM3 50 GA ED £299, MM3 60 GA ED £399 Recommended eyepieces: HDF T 12-36x/15-45x £199, SDLv2 12-36x/15-45x £289
Opticron equipment can be tried, tested and purchased at good optical retailers nationwide. For product information, your nearest stockist and to order a Product Guide please phone us on 01582 726522 or visit us online at www.opticron.co.uk Opticron. Unit 21, Titan Court, Laporte Way, Luton, Beds, LU4 8EF UK Fax: 01582 723559 Email: sales@opticron.co.uk
BTO Volunteer 2015.indd 1
12/03/2015 16:48