The Joy of Nesting Birds

Hazel Evans writes:

This week (14th – 21st February) is the BTO’s 21st National Nest Box Week.  Each year we encourage anyone who is interested, to put up nest boxes locally. I’d like to delve in to some of the different aspects for why this is such a wonderful thing to do, and how we can make the most of them.

The first and most obvious reason is to give birds a place to raise their young. In areas of human habitation it can be harder for birds to find places to nest, so putting up a nest box is a good way to ensure there is somewhere for the birds to use. There are many external factors which may affect the outcome of a nesting attempt, but we can offer them a good place to start. You may also choose to put out some appropriate nesting material in the nearby trees and bushes, or grow some plants to encourage insects. Non-native plants in gardens have been found to be a potential detriment to our local birds, they do not provide as much food, because non-native plants may not be able to host as many caterpillars as native plants, so this may be something to consider.
 

Robin feeding it's young. Photo by John Harding

The second reason why putting up a nest box can be important is monitoring. One of the BTO’s strongest assets is the data it has collected through organising monitoring schemes, and the Nest Record Scheme (NRS) is no exception. Now running for over 75 years, close to two million records of nesting birds throughout the UK have been sent in for over 200 species. This includes data from open nesting birds and nest boxes, both of which are highly valuable. As long as the NRS Code of Conduct is adhered to, we can safely record the progress of nesting attempts by counting the number of eggs and chicks and recording the outcome of the attempt and submitting data to the NRS.

Blue Tit fledgling. Photo by Christine M Matthews

The third reason I value nest boxes very highly, is the intrigue and excitement they can provide. Anyone can put up a nest box and monitor what’s inside it and in turn benefit from watching the behaviour of the birds. Interactions with the natural world have been shown to help relieve depression, anxiety and stress. We are living in a time where it is easy to lose touch with the natural world and many children aren’t getting experiences with nature; having a nest box in your garden is an inspiring way to learn about the natural world. Monitoring nests is not something that should be taken lightly but with the knowledge that the data is going to a good cause, it's something we can experience great joy from.

Now is the time when garden birds are just starting to prospect nesting sites in preparation for the approaching spring, so the sooner you can get a box up the better, whether you build it yourself or buy it from the garden centre. There are many bird species which use nest boxes, so if you have a bit more space then you may want to put up a larger nest box, for a Kestrel or owls.

Once used, it is a great idea to clean out old nests the following winter to allow for a fresh start in the spring. To comply with legislation, nests should only be cleaned out between 1 August and 31 January.

Little Owls in Lincolnshire

Anecdotal reports suggest that some species have started breeding early this year. In this post, Bob Sheppard provides an update on the Little Owls he monitors in Lincolnshire:

Little Owls readily take to nest boxes, particularly in old farm buildings. The box design I use is important as it mimics a hole in a tree. My father designed the box back in 1998.

A very big clutch of Little Owl eggs. Taken by Bob Sheppard/Alan Ball.

In the past nineteen years our Little Owls have increased as more boxes have been installed and we now have 80 pairs breeding. We monitor the adults for the Retrapping Adults for Survival scheme as well as submitting records to the Nest Record Scheme. In late April/early May, my colleague Alan Ball (who works with me to monitor all the boxes every year) and I catch all the adult females at the boxes (males are rarely caught in the boxes). The females are very site faithful and so we often retrap the same birds for several consecutive years. We then make a follow up visit to ring the chicks.

Little Owl struggling to sit on all those eggs. Taken by Bob Sheppard/Alan Ball.

This year we have found eggs during the first week of April which is very early indeed for Lincolnshire. Clutches of four are the average but we do find quite a few fives, including three already this season. Six egg clutches are not unknown and we once had a seven! The egg-laying season is unusually staggered this year; in several boxes we have heavy females yet to lay. Recoveries are rare (see online reports) but we meet lots of old friends as we open the boxes.

Ed - For more information on the details of Little Owl biology, see our BirdFacts page. Lincolnshire holds the record for the highest number of nest records of Little Owl (77) in 2016, with Norfolk following quite a way behind (14). For the 2015 results of any species click here.

Feeling a bit broody

With winter loosening its grip on the British countryside our bird life is starting to look forward to spring! Here at BTO HQ, we are winding up to a busy nesting season and are searching the hedgerows and bushes for nests.


Egyptian Geese - photo by Rachael Barber

So far this year we have found nests of Coot, Egyptian Geese, Mallard, Robin, Blackbird, Song Thrush, Long-tailed Tit, Wren, Collared Dove and Dunnock, with more species being added every day. Each nest will be fully recorded for the BTO Nest Record Scheme (NRS) with nest finders following the NRS code of conduct.


Mallard nest with nine eggs - photo by Lee Barber

Robin nest - photo by Rachael Barber

Several BTO staff and volunteers record nests around Thetford, Norfolk, but how do we avoid recording the same nest? The answer is that we share a Google Map between us, with colours and shapes used to denote the progress of each nest and a note included of who found the nest. After a day of 'nesting' we update the map with our exciting discoveries and this informs everyone of where the nest is, the species, when it was found and at what stage the nest is at (nest only, nest with eggs, chicks, not active). Each recorder will then follow 'their' nests and submit them to the BTO (usually via the ringing group) at the end of the season/nest completion.



Last years nest locations on a shared Google map

Across the country there are some species that have been nesting for some time already including Grey Heron, Raven, Dipper, Stock Dove, Cormorant and Crossbill. The BTO NRS Forum has come alive with reports of nests, includes a Peregrine laying in Woking, Surrey (webcam link), a Woodpigeon squab about two weeks old in North Cornwall and Moorhen, Mistle Thrush and Ring-necked Parakeet with eggs in London. Dippers have full clutches in the Scottish Borders and some chicks have already been ringed in Wales. A Stock Dove in North Norfolk must have fledged by now as well.


 

Blackbird nest - photo by Lee Barber

Nest recording is vital to our understanding of productivity and every nest counts! It is amazing how much difference one nest record can make. By looking at the NRS submission totals, you can see what nests have been recorded previously (2016 records are still being analysed). In 2015, just 24 Goldcrest, 15 Snipe and nine Grasshopper Warbler were recorded in the whole country. Take that down to the county level and you could make a big difference to the totals, especially if you focus on one particular species. Open nesting birds are particularly under recorded because they are generally harder to find, but with a little practice and patience it can be done. Click here to find out how to take part and develop your nesting skills.

Two broods are better than one

Hazel Evans, NRS secretary writes:

Studies in Europe demonstrate that Great Tits have the potential to produce two broods per season; a recent study of populations in The Netherlands showed that over 50% of birds were double-brooded in the 1960s, though this number has been declining as the climate warms. Despite this observation, records of double-brooded Great Tits are still relatively scarce in the UK – is this because it is truly a rare behaviour or because we’re so used to thinking of them as single-brooded that we don’t often check our boxes after the first chicks have left?

Robin and Moya Myerscough from Norfolk have been keeping a very detailed log of the comings and goings at their garden in nest box during 2016. A female Great Tit began laying on 6th April and completed a clutch of nine, which hatched on the 27th. Unfortunately two chicks died but the remaining seven fledged successfully at 08.15 on 17th May.

Female Great Tit collecting nesting material. Photo taken by Jill Packenham

These observations constitute a great record for the BTO’s Nest Record Scheme but nothing seemed particularly out of the ordinary. However, by 2 pm an adult was bringing in fresh nesting material and it laid the first egg of a second clutch the very next day.  This in itself is unusual, but a gap of less than 24 hours between attempts seems amazing. Great Tit fledglings are heavily dependent on their parents for about a week after leaving the nest but it is possible the female was able to juggle these responsibilities with laying of the second clutch, given incubation does not commence until the penultimate egg is laid.

Great Tit removing a fecal sac. Photo taken by David Waistell

In truth, while it seems rapid, we don’t really know just how this observation compares to the typical interval between broods, but the widespread use of nest box cameras has the potential to significantly increase the amount of information we are able to collect. Whether you own a camera or not, it’s worth keeping a close eye on your nest boxes over the next couple of weeks to check for second broods – remember to submit records of any attempts you find  to  the Nest Record Scheme or Nest Box Challenge.

Making a home for my ‘tweet’ Valentine

Hazel Evans, Nest Box Challenge Organiser writes:

There is still a chill in the air, but at last the days are getting longer and it’s time to think about where our local birds will be nesting this year. Valentine’s Day sees the start of BTO and Jacobi Jayne’s annual ‘National Nest Box Week’. The aim of the week is to encourage and promote the putting up of nest boxes in your local area.

There are numerous reasons why I advocate nest boxes and it can be as easy as you like to take part. The simplest thing you can do is to go to your local garden centre and purchase a suitable Nest Box and put it up in your local area. This may be your garden, but if you are looking further afield, a local park or woodland is also great (as long as you have the land owner's permission). As old trees fall or are cut down, houses are better insulated and gaps under the eaves are sealed, there are fewer natural cavities available for nesting birds so providing artificial nesting locations is extremely valuable.

Robin in an open fronted nest box. Photo by John Cranfield

Once you’ve put up your nest box - or filled your local park with them - monitoring is where the real conservation value lies. Nest boxes give us the opportunity to easily collect data on the breeding success of cavity nesting birds; the same data can require a little more time and skill to collect from natural nest sites. As long as the NRS Code of Conduct is adhered to, we can safely record the progress of nesting attempts by looking inside next boxes to count the number of eggs and chicks and submitting data to the Nest Record Scheme (NRS). There is a very large body of research showing that the contents can be examined without any negative impacts on the outcome of the breeding attempt.

NRS participants monitor nests by inspecting them at intervals and recording the number of eggs laid, the number of chicks hatched and whether chicks fledge successfully. This information is used by the BTO to study the breeding performance of wild birds to help identify when reduced productivity might be causing population declines. People can be concerned about opening up a nest box and checking the contents, but done in the correct way the value of the data collected is huge.

Blue Tit chicks. Photo by Simon Thurgood

By far the most common inhabitants of garden nest boxes are Blue Tits and Great Tits. They have adapted so well to living in our man-made constructions that we receive thousands of nest records for these species every year. These records provide such good national coverage that it is possible to explore the degree to which birds' responses to changes in the environment vary between regions and habitats.

At the other end of the spectrum are Treecreepers, which have so far not adapted to using nest boxes. A nest recorder recently developed a design which mimics the thin, natural cavities preferred by Treecreepers. If you would like to have a go at making one of these boxes then please do let the Nest Record Scheme know whether the box is used or not. If it is used then you can also submit a nest record.

Treecreeper. Photo by John Bowers

A huge variety of nest boxes are available to either buy or to make and you can find information to help you choose an appropriate box on the National Nest Box Week website. When choosing a box it is important to make sure the lid can be lifted or removed to allow you to monitor the contents (or that you can appropriately modify it) and that it is well constructed from a thick enough (and appropriate) material to protect a clutch of very small, very vulnerable chicks! Building a box can also be very rewarding and save a lot of money.

Nest boxes can of course be put up at any time of year but winter is ideal as it provides time for prospecting birds to find the site before the breeding season. Once used, it is a great idea to clean out old nests the following winter to allow for a fresh start in the spring. To comply with legislation, nests can only be cleaned out between 1 August and 31 January.

Owl and raptor mid-season update

That annual Barn Owl breeding success is influenced by peaks and troughs in abundance of field voles, the species' main prey item in many areas, is hardly news to Barn Owl recorders. But after seeing some of the lowest levels of nesting activity in memory in 2013, followed by record productivity in 2014, many might be wondering just when they'll next get an 'average' season. Not in 2015 it seems: anecdotal reports so far suggest Barn Owl productivity has been much lower than expected, though other species seem to have followed on better from last year's bumper season.

Poorer than predicted Barn Owl breeding

Back in February, Barn Owl expert Colin Shawyer predicted that, provided spring conditions remained mild, the exceptional number of 2014 fledglings would mean good recruitment of young breeding birds, but also that though egg-laying could be expected at the usual time in late-April/early-May, a decline in vole numbers from their 2014 peak would result in smaller brood sizes and fewer fledglings this year.

Subsequent early visits to Barn Owl nest boxes revealed much less activity than expected. In late May, Colin visited 25 boxes that had contained 16 active nests in March 2014, only to find just eight with signs of adults present and three clutches of eggs. Non-breeding females were found to be underweight, suggesting that, whether caused by recent wet weather affecting foraging or simply the scarcity of voles, birds were late getting into breeding condition.

By mid-June, reports on the NRS Forum were sounding similar. Alan Ball, Bob Sheppard and Keith Bowden, in Lincolnshire, had checked most of their boxes and found four Barn Owl pairs on eggs or chicks. On the same date in 2014, they had been monitoring 200 nests. Frank Mawby, in Cumbria, Peter Wilkinson, in Cambs, and David Garner, in Cambs, were also reporting low breeding occupancy, and an apparent shortage of prey. Bob Danson, a recorder in Lancashire, commented that food larders had disappeared after the very beginning of the season, in contrast to 2014 when piles of six and seven voles were common.

A single Barn Owl chick at 20-25 days. In 2015 there have been many reports of broods sizes dropping to just one or two chicks. Photo by BTO.

In mid to late July, when Barn Owl chicks are often ready for ringing, there were reports of brood sizes of three and four having reduced to just one—Mike McDowall in East Lothian, David Garner in Cambs and Frank Mawby in Cumbria all ringed single chicks. By the time Bob Danson had ringed his latest brood on 3 August, just eight of the 23 nests he had found so far in his 80 boxes had produced chicks, and his ringing total had reached only 18.

Better Barn Owl news has come in from elsewhere: Nigel Lewis at Salisbury Plain observed a good proportion of boxes with clutches of eggs in May and Judith Smith, in Manchester, has ringed several healthy broods of four and five chicks, including some in new boxes. Geoff Myers, in Lancashire, reported that good numbers of both early and later laying Barn Owl pairs had successfully reared broods and that by 24 June he had ringed a brood of six and several broods of five—very advanced compared to elsewhere.

Tawny Owl, Little Owl and Kestrel fortunes

There have been mixed reports for other box-nesting owl and raptor species that tend to be well-monitored by ringers and nest recorders. Alan Ball, Keith Bowden and Bob Sheppard reported that they had ringed just six Tawny Owl chicks in their boxes in Lincolnshire, compared to 130 in the same boxes in 2014. On the other hand, Bob Danson, in Lancashire, encountered 17 nests in 30 boxes—his second best annual total after last year—from which 26 chicks fledged, including four broods of three. Bob noticed that rats made up a higher proportion of prey in his Tawny Owl boxes, along with baby rabbits.

Several recorders have spoken of Little Owls doing well this year, a species that is obviously less dependent on rodent prey. Alan Ball, Keith Bowden and Bob Sheppard monitored 65 nests and ringed 100 chicks, compared to 80 nests and 188 chicks in 2014. Bob Danson's 70 Little Owl boxes saw occupancy increase to 16 pairs in 2014, from 12 in 2014 and 7 in 2013. He recorded 36 fledged young altogether, including a brood of five and two broods of four.

Two recently fledged Kestrels photographed by Wilf Hockney, who accompanied Steve Baines on several of his Kestrel box rounds this year. 

Kestrel reports have also been positive. Steve Baines monitors 20 boxes in Chelmsford, Essex, and 13 had pairs this year, one of his highest occupancy rates, though he noted that clutch sizes were down relative to 2014: clutches of five and four but no sixes, and that the number of chicks fledged overall (36) was slightly lower than 2014. Bob Danson reported a similarly successful season for Kestrels in Lancashire and noted more bird prey in boxes than usual, including a Swallow. In contrast, Alan Ball, Keith Bowden and Bob Sheppard had monitored only 6 nests by mid-June, compared to 150 at the same time in 2014.

Late season comeback?

Although the breeding season has now finished for Tawny Owl and Little Owl—bar perhaps a few exceptionally late nests—there will still be a proportion of Kestrels tending to chicks, and of course there is the question of whether we will see any Barn Owl second broods or late-season nesting attempts in previously empty boxes. As Dave Leech has pointed out in a recent interview for Radio 4, this might happen if non-breeding females have managed to get into breeding condition, although Colin Shawyer has observed that vole numbers appear to remain very low. Either way, good data on the extent of late and repeat broods is essential for assessing Barn Owl productivity, which is why those late-season box checks are so important...

The BTO Nest Record Scheme is one of the ways in which raptor populations are monitored in Britain & Ireland. These results are complemented by periodic single-species surveys and, in Scotland, by the Scottish Raptor Monitoring Scheme.

Many thanks indeed to: Steve Baines, Alan Ball, Keith Bowden, Bob Danson, Wilf Hockney, Nigel Lewis, Frank Mawby, Mike McDowell, Geoff Myers, Colin Shawyer, Bob Sheppard, Judith Smith, Peter Wilkinson

Found a ringed bird? You are not alone.

With around one million birds ringed every year it is not surprising that we get quite a few phone calls and lots of emails to the ringing team from non-ringers reporting a ringed bird. We get back to each one a few days later with a report on where and when the bird was ringed, and at the same time let the ringer know that one of 'their' birds has been found.

When you add this to all of the recaptures of ringed birds by our ringers through general ringing, especially structured ringing like Constant Effort Sites and Retrapping Adults for Survival, the value of these reports to conservation is huge. There are many aspects of a bird's life that can be investigated by BTO scientists and academics, particularly when results from other BTO surveys, such as the Nest Record Scheme and BBS, are included in the dataset.

Great example of part of a Dunnock nest record by Christopher Rowe

Most of the non-ringers that report ringed birds just get information on the bird they found and are unaware of the magnitude of records that we process. I have looked into the 40,394 reports that have been sent to us so far this summer (since 29 March 2015) from ringers and non-ringers.

Below is a chart showing the percentage of each species that were found by non-ringers and caught by ringers. Blue and Great Tit are of course the top two, followed by other garden birds. Starling is unusually high due to some great Starling colour ringing projects operating from Essex to Montrose. We have had singles of some unusual species so far this summer including Icterine Warbler, Capercaillie, Ruddy Duck and Great Bustard but these are few and far between.

Finding reports sent in to the BTO so far this summer from ringers and non-ringers. Click chart to enlarge.

The chart below is purely those reported by non-ringers. Considering the recent declines in House Sparrow and Starlings, the reports of them are quite high but this is due to the increased conservation effort and colour ringing projects occurring on these species. Fifteen percent for Black-headed Gull isn't surprising for us as a large percentage of the Recoveries Officers' work is processing colour ring sightings of these birds moving between countries and within our country. There is also a large number of people devoted to gulls and ring reading.

Finding reports from this summer from non-ringers only

Our valued BTO ringers not only ring large numbers of birds, to increase our understanding of our bird populations, but they also recapture large numbers of birds that are already ringed. This accounted for 81% of all the birds 'encountered' and reported since 29 March. These are reported to us using a dedicated computer program and thankfully need less processing than non-ringer reports. Out of the non-ringers reports 78% are colour ring sightings - see below for the top 10 circumstances of the report. Discerning the cause of death can be difficult and these records are represented by the red slice on the chart below.

The top 10 circumstances that led to us getting a report this summer.

Nest with the best

Over 250 keen NRS participants have attended BTO nest recording courses since veteran recorder and volunteer tutor Tony Davis ran the pilot in 2008. This year, thanks to BTO Scotland and recorders Colin Davison and Gilian Dinsmore, the regular weekend courses in Norfolk and Surrey were joined by a brand new afternoon workshop at Scotland's Big Nature Festival.

Punchbowl pipits

Five weeks ago nine more keen recorders met Tony at the Devil's Punchbowl in Hindhead, Surrey, to spend a weekend increasing their nest finding knowledge. Saturday was spent learning to find warbler and finch nests in gorse at a nearby heath, and looking for Skylark nests at Butser Hill. Then on Sunday the group descended into the Punchbowl itself and soon found what appeared to be two Tree Pipit territories either side of the main path. The next hour was spent practicing watching nesting activity unobtrusively, which for wary Tree Pipits often means at least 50 metres back! One pair turned out to be feeding fledged chicks and an hour spent on the other territory proved inconclusive—at least for the target species. After standing in the same spot for 20 minutes, attendee Colin became aware of a Robin stealthily taking food into a patch of gorse immediately behind him. The bird was watched carefully for two more visits, the 'hotspot' was searched, and a nest found containing four young. Nest number 15 out of 25 found over the whole weekend—plenty for Tony to follow up!

Top: Colin Wilson searches for a Robin nest after watching an adult carrying food. Bottom: Trainee Teifion Thomas rings a brood of Robins from another nest, while ringer Colin Wilson supervises

Scotland's Big Nature Festival

The weekend before the Surrey course, Scotland's Big Nature Festival played host to its first ever nest recording workshop, thanks in part to a local volunteer who couldn't actually be there on the day. Keen for the workshop to include an outdoor demo where people could be shown nests and how recorders safely monitor them, BTO Scotland realised that one of the country's top nest recorders, Colin Davison, lived near the venue. When they contacting him about helping, Colin said that he was working that day but would try to find a few nests in advance—and then promptly located 12!

Top: veteran nest recorder Colin Davison pointing out the location of a Chiffchaff nest. Bottom: Ben Darvill takes people on a bird song tour as part of BTO Scotland's roster of events at the 2015 Big Nature Festival

The workshop was very well attended and began with talks from Mark Wilson (BTO Scotland) on why Scotland needs more nest recorders and another local recorder (and Reed Warbler expert) Gillian Dinsmore on her experiences getting started. Mark and Gillian then announced the outdoor demo and were delighted when 30 keen members of the public stepped forward. Folk were divided into groups and taken on carefully planned tours of Colin's nests, which included some in cover (Blackcap with eggs, Robin with chicks), some on the ground (Skylark and Meadow Pipit, both with eggs), and a Blue Tit nest in an unbelievably narrow crack on the wall of one of the observation hides. It was great to see so many people interested, especially given the pressing need for more recorders in Scotland, and needless to say plenty of NRS starter packs were given out. Both Colin and Gillian have pledged their support for future workshops—hopefully Colin will be able to attend the next one!

Interested in going on a nest recording course? Please see here.

A huge thanks to volunteers Tony Davis, Colin Davison and Gillian Dinsmore for making this years' courses/workshops possible, and a huge thanks to BTO Scotland staff Ben Darvill and Mark Wilson, and BTO Thetford staff Mike Toms, Hazel Evans and Debbie Todd. And of course thank you to all the course and workshop attendees!

Chiff-ful start to the nesting season

Over in Cambridgeshire there’s been wonderful sunshine, but accompanied by overnight frosts. Thankfully this hasn’t put off the resident birds at the National Trust’s Wicken Fen National Nature Reserve, where members of the ringing and nest recording group are getting ready to ring the first broods of Blackbirds. Also, our first Coot brood has just hatched, Long-tailed Tit clutches are about to hatch, Blue Tits and Great Tits are laying, and we’ve started monitoring our first finch nests: an almost fully-built Chaffinch nest was found a week ago and a pair of Goldfinches were spotted building last Thursday.

Water birds such as Coot (pictured) and Moorhen commonly hatch their first broods in mid-April

As for summer migrants, arrivals have been stalled by strong north-westerly winds, according to the BTO migration blog, and indeed Blackcaps at Wicken have been singing on territory for only a week and Willow Warblers still seem thin on the ground. One short-distance migrant, though, has been getting off to a flying start this season and keeping our nest finders very busy: Chiffchaff!

During Easter weekend we saw plenty of male Chiffchaffs singing from tree tops but no birds skulking lower down (a tell-tale sign of a female getting ready to build). Last Monday, things had got busier: males were singing back-to-back and chasing each other off territories and ‘hueet’ contact calls could be heard everywhere. Then, on Tuesday 14, we caught our first glimpse of a bird with a beakful of long grass—a building female! Early next morning we spotted another bird building and then on Thursday 16, Anne, our main nest finder, found five more nests, some almost fully formed (a characteristic domed construction). By Monday 20, we had found 11 nests, two lined with feathers, and that morning we found nest number 12 at an early stage, the female pinging back-and-forth with large bits of material.

Chiffchaff nest at Wicken Fen in 2014. Built just above the ground, the nest is dome shaped, made from reeds and some finer grasses, and lined with feathers. c.200 Chiffchaff nests are monitored across the country for NRS each year.

So what to expect this weekend? Those lined nests will probably have eggs, though females may still be building on other territories. Nest recorders elsewhere have begun reporting Blackcaps on eggs, Whitethroats and Willow Warblers building, and Chaffinches on full clutches.

How far along are nesting birds on your patch? Help the BTO collect vital data on nest productivity and timing of breeding by taking part in the Nest Record Scheme.

Happening in a box near you

National Nest Box Week kicks off every year on Valentine’s Day. It’s a week where the BTO encourage members of the public to put up nest boxes in their gardens. Our garden birds are just starting to prospect nesting sites in preparation for the approaching spring, so the sooner you can get a box up the better, whether you build it yourself or buy it from the garden centre.

Great Tit - David Waistell

There are increasing concerns that the availability of suitable nesting cavities is falling as old trees are felled and houses are repaired, so erecting a box could make a real difference to a pair of birds in your garden. However, the real conservation value of erecting a box is the opportunity it provides to safely record the progress of the nesting attempt, looking inside at intervals to count the number of eggs and chicks and submitting data to one of the BTO’s nest monitoring schemes. The benefits of your monitoring efforts will be felt well beyond the confines of your garden, benefiting national bird populations by helping conservationists to understand the impacts of climate change and urbanisation on the number of young reared and therefore, ultimately, on population trends.

Blue Tit nest - Hazel Evans

Nest Box Challenge  (NBC) is an on-line monitoring survey focussed on gardens, with the ability to record data on both box-nesting birds, such as Blue Tits, and open-nesting species, such as Blackbirds and Woodpigeons.  The Nest Record Scheme (NRS) collects more detailed data on all nesting species across a wide variety of habitats. People are understandably wary of approaching nests, but there is a very large body of research showing that the contents can be examined without a negative impact on the outcome of the attempt, as long as the guidelines set out in our NRS Code of Conduct are followed.

The number of people nest recording in the UK has never been higher, with almost 1,000 volunteers monitoring over 45,000 nesting attempts in 2014 alone through NBC and NRS. 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, creating an invaluable and unique record of the UK’s breeding birds. These data are used to generate annual trends in laying dates, the number of eggs produced and the number of chicks reared, which are published each year in the BTO’s BirdTrends report. By analysing nesting data in conjunction with survival data generated by bird ringing, we can assess the contribution that changes in the number of fledglings produced makes to national population trends.

Blue Tit fledgling - Tommy Holden

By far the most common inhabitants of our garden nest boxes are Blue Tits and Great Tits. They have adapted so well to living in our man-made constructions that we receive thousands of records every year; so do we really need any more? The answer is a resounding ‘Yes’, as the better the coverage, the more we can explore the degree to which birds responses to changes in the environment vary between regions and habitats. Your help is vital in continuing to build on this amazing dataset, so why not make 2015 the year you start monitoring nests?


By Hazel Evans, Nest Record Scheme secretary

2015 nesting season underway by New Year!

Dave Leech writes:

For many BTO nest recorders, particularly those monitoring Barn Owl repeat breeding attempts well into the late autumn, it feels like the 2014 breeding season has only just drawn to a close. However, the respite is brief – while we seek shelter from the biting winter gales, the avian community is gearing up for the coming spring.

The Met Office have recently announced that 2014 was the warmest year on record in the UK and this winter has certainly been mild if, as most bird ringers will point out, a tad windy. Mild weather at the start of the year can certainly stimulate opportunistic singing, and I’ve already heard Great Tit, Wren and Dunnock in song within walking distance of my house in southwest Norfolk; nest recorder Mark Lawrence has been listening to the reedy warbling of the latter since early December on his patch in Devon.

Dunnock singing - Liz Cutting

While the nestling diet of these birds is not necessarily conducive to early breeding, species able to take advantage of soil invertebrates are less limited by food availability and may breed opportunistically at the end of winter, particularly around human habitation where temperatures are artificially raised and bird feeders provide additional sustenance. Nest recorder Mark Lucas has already reported his first clutch of Robin eggs in North Yorkshire via Twitter, found on the 9th January, beating the earliest record submitted to the BTO Nest Record Scheme by a fortnight. A pair of Mistle Thrush breeding in a Glasgow park were also flagged up on Twitter, the young having fledged in the last week.

Mistle Thrush nest - Herbert and Howells

Some birds couldn’t even wait for the New Year to start the 2015 season. RSPB warden Doug Radford was told of a Moorhen on eggs in Cambridgeshire in mid-December which had hatched by Christmas, and we’ve also received reports of Grey Heron laying at the start of the month. Not to be outdone, the BTO’s own Nick Moran stumbled across a brood of small Mallard ducklings on the 12th December at our reserve in Norfolk.

Mallard with ducklings - John Harding

While these examples demonstrate birds ability to respond to windows of opportunity, they are all anomalies. The data collected by BTO volunteers for the Nest Record Scheme over the past 75 years tells us that the main Robin breeding season kicks off towards the end of March, while most Moorhens start to lay from the beginning of April onwards.  Grey Herons are early breeders (Table 1), but laying doesn’t typically start until mid-February, with Raven generally the next species to follow in any number, then Tawny Owl, Collared Dove and Magpie at the very beginning of March.

BTO data have played a key role in demonstrating the advance in avian laying dates in response to the warming climate, as summarised in the recent BirdTrends report, and it is vital to ensure that this monitoring is ongoing. So, if you’re looking for a New Year’s resolution that furthers your knowledge while also giving something back to the conservation effort, why not make 2015 your first year as a nest recorder?

Table 1. Top 10 earliest UK breeders as calculated using Nest Record Scheme data for the period 2000-2009. Dates shown are the fifth percentile of the laying date distribution. Note that some early breeding species (e.g. Long-eared Owl, Crossbill) are excluded due to very small sample sizes.

Merry Christmas from the Demography Team

As we move closer to Christmas, many bird ringers will still be out collecting valuable data on our bird populations across a range of habitats, from gardens, woods and farms to salt marshes and estuaries. Winter ringing tells us a lot about the survival and movements of birds in response to weather and can also be used to assess the breeding success of birds that nest outside the UK, such as wildfowl and waders. We've received information about just over 763,000 ringed in Britain & Ireland during 2014, which is 55,000 more than this time last year, and expect many more records to arrive over the next few weeks.

Coal Tit - Lee Barber

This period of the year is a little quieter for nest recorders, although those out monitoring Barn Owl second broods will have only just laid their ladders down after an incredibly prolific season. With temperatures above average for the time of year, however, it's always a good idea to keep an eye out for signs of opportunistic nesting behaviour, particularly in gardens and around towns where the climate tends to be warmer and many homeowners are providing extra food. Data from this summer are still flooding into the Nest Record Scheme thanks to the amazing efforts of our volunteers, and we've received over 36,000 nest histories so far, over 2,000 more than at this stage last year. As with the results generated by ringers, this information will be used to improve our understanding of the role that survival and breeding success play in driving population trends.

BTO Blue Tits - Sue Lawrence

On behalf of the birds and the BTO, we would like to thank all our ringers and nest recorders for their support and hard work during the year, and all readers of this blog for your interest in, and support of, these vital surveys. If you're not yet involved and fancy making bird surveying one of your resolutions for 2015, why not have a look on our survey pages to find an option that suits you?

Merry Christmas and a Happy New Year from all of us at BTO HQ!

2014 proves a good vintage for breeding birds

Throughout the year, ringers and nest recorders have been sending us their impressions of the breeding season. A post in June discussed how the weather in spring made for good nesting whilst one in July considered whether it was nearly time for nesters to hang up their mirrors for the year. On to September and we were reporting on the huge numbers of Blackcaps moving through the country and suggesting that this might be indicative of a good breeding season. Finally, in October, we pulled together stories suggesting that it might be one of the best years yet for Barn Owls. So, do these stories match what the results from the Nest Record Scheme (NRS) and the Constant Effort Sites (CES) scheme tell us? The 2014 preliminary results have just been published and can be found on both the NRS and CES pages of the website.

Barn Owl (photo by Jill Pakenham)

We are very happy to report that the NRS and CES results show that 2014 was indeed a bumper breeding season for both Barn Owl (best ever) and Blackcap, as well as many other species, with the large number of young fledged and high levels of repeat nesting keeping volunteers busy throughout the summer. Reed Warbler, Blackbird and Bullfinch all exhibited the highest levels of productivity since CES began in 1983; interestingly, the two previous best years for Bullfinch were 2011 and 2013.

Less positive were the abundance results which showed that many of our migrants, particularly long-distance visitors, were notable by their absence this year. Only Chiffchaff broke the mould and exhibited a significant increase in abundance. News wasn't great for our resident birds either with only Robin and Wren managing to take advantage of the mild winter and exhibit a significant increase in numbers.

Chiffchaff abundance trend

Those who went to the annual BTO Conference at Swanwick this weekend would have seen the poster showing the regional CES results. While breeding success was generally high across Britain & Ireland, some species displayed regional variation - Sedge Warblers produced more young in the north than in the east or west for example. We would love to hear how your own experiences compared to the results presented so please feel free to leave a comment below. 

CES results poster showing national and regional results (click to enlarge)

We would like to thank all the ringers and nesters who contributed to the CES and NRS schemes this year and to those who provided blog stories in 2014. We hope you enjoyed the season and we look forward to reporting on your 2015 exploits.

Keeping Starlings under surveillance

Graham Martin, Worcestershire writes:

While local bird watchers have been marvelling at some spectacular murmurations of Starlings, my attention has been focused very closely on my local colony of about two dozen resident Starlings.

I have eleven boxes up around the garden and for the last five years, one has been rigged with a standard IR nest box camera. Ten of the boxes are now occupied and breeding has got underway very early this year, with the first egg laid on March 18th, in the camera nest box. According to BTO records, this is the 9th earliest date ever recorded for Starlings. It was 25 days earlier than the first egg that I observed in 2013.

Starling under surveillance - Graham Martin

One very interesting behaviour has been the male singing at full volume repeatedly from within the box. Given his mimicry this has meant that from my box I have had a succession of Buzzards, Chickens and Little Owls.

The first egg appeared and was duly noted on March 18th, but on the second day I switched the camera on at 06:00 and soon after watched as a bird entered the box, poked around a bit and then removed the egg. Fifteen minutes later a bird entered the box and showed more nesting behaviour until at about 10:00 another egg was laid. So the nest record now shows two successive days with one egg but because of what the video revealed, I know that this is in fact the second egg for the nest.

Starling - Terry Levitt

Just what is going is very difficult to say. Last year I also recorded two successive days with just one egg. At that time I assumed that the female had just interrupted laying for one day, but it could well have been that the first egg was also removed last year. Who took the egg? There are many options but it could be another female from one of the nearby nests helping herself to some ready nutrients or it could be a rival male trying to decrease someone else’s paternity.

I hope that this year, because of the early breeding and the mild and damp conditions, these starlings will be able to produce two broods, like last years camera box nest, but whether it was the same adults will remain a mystery.

Let the nesters... nest!

During the winter months, nest recorders (known as nesters) all around the country are eagerly waiting the first signs of spring. Some start in February when pigeons, Ravens and Cormorants are starting to breed. We have posted previously on nesting Tawny Owls, some of which would have left their nest by now, but spring is really here when we receive our first reports of our garden birds nesting.

While walking through Thetford, Norfolk last Friday on a cold and dreary morning, I came across two Blackbirds fledglings being fed by their parents (below). They had been seen earlier in the week and by now had become very obvious. The eggs of this brood must have been laid in January as they were reasonably well developed but still very reliant on their parents. Unfortunately during my lunch break today, I found one of these fledglings on the road, after being struck by a car but the other one is still alive and well.

First Thetford Blackbirds of the season - Lee Barber

Another classic garden bird is the Robin. In the BTO grounds they are usually very elusive but after seeing a Robin in the same place on Thursday, Friday and today, I can finally confirm that another BTO nest is underway with a part built nest.

We will of course be following the progress of these two 'nests', and we will add many many more during the season. We will shortly be out looking for Long-tailed Tit nests while they are building their domed lichen nest, but if you have never recorded a nest before, get in touch with us at the NRS website and join us with our notebooks and nesting sticks.

Nunnery nesting in 2014: off the mark!

We’re fast approaching the time of year where I grab my trusty nesting stick, Carl Barimore reaches for his mirror on a pole and Mike Toms straps on his endoscope as we head down to The Nunnery reserve to start looking for nests to monitor. We generally begin searching in late February, when the Long-tailed Tits begin to pair up and hang suspiciously around likely nesting sites (here typically gorse or bramble) and the first grebes, Mute Swan and Coot start gathering material. However, we’re always on the lookout for opportunities before that, and one was provided on the 15^th January by our colleague, Neil Calbrade, who spotted a sitting Collared Dove in the Nunnery garden, the nest wedged between the branches of a  yew about 3m off the ground. This morning was the first chance I had to check it and the bird flew on my approach to reveal a single white egg; the ‘standard’ clutch size is two, but clutch sizes of early attempts made by multi-brooded species are often smaller (single-brooded species show the opposite pattern).

The typical view of a Collared Dove nest is the underside of a twiggy platform, several metres off the ground in a tree or shrub. It is almost always possible to see the adult sitting from the ground. Photo by  B Besley

It may be tempting to blame the unseasonably warm weather for this apparently early attempt, but Collared Dove is actually the only species in the BTO Nest Record Scheme (NRS) dataset that has been recorded as breeding in every month of the year (Fig 1), although if as many recorders focused on Mallard, it may well reveal the same pattern.

Number of NRS Collared Dove records for which an accurate laying date can be calculated by month in which first egg was laid

That said, fewer than 30 January attempts are logged in the NRS database, dating back to the mid-1960s, and this is the fifth nesting Collared Dove nest we’ve been informed of in the past fortnight (the third in Thetford alone), which suggests they may have made an early start.  It is impossible to compare years without first collecting the data, however; analyses are orders of magnitude more powerful than anecdote when it comes to influencing Government policy on climate change, so it is vital your records are submitted to a national nest-recording scheme.

So, why not make 2014 the year that you register with the Nest Record Scheme and get involved in nest recording – it’s great fun, you’ll learn a huge amount about the birds around you and, vitally, it provides information to support conservation efforts that can’t be gathered any other way.

Information about any species, no matter how common, in any habitat, be it your garden or a remote island, are of value as long as you can see inside to count the eggs and chicks. Looking in nests is perfectly legal as long as you don’t handle the contents, although a licence is need to monitor nests of Schedule 1 species and be sure to follow the NRS Code of Conduct

We’ll be monitoring the progress of our Collared Dove and about 400 other nests across The Nunnery over the course of this season, from Wrens to Mute Swans; we’ll keep you posted on our progress and we look forward to hearing about yours.

Dave Leech, Head of the Nest Record Scheme

http://www.bto.org/sites/default/files/u15/downloads/publications/legislation_and_good_practice.pdf

How do you like your eggs? Frozen

The start of each year sees some pretty intense competition between BTO staff – who will be first to see a rarity on the Nunnery Lakes (generally Nick Moran), who will have the highest list at the end of January (Nick, again), who will catch the most Siskins (Allison Kew, with Greg Conway or Graham Austin a close second), etc, etc. From my point of view, the greatest accolade is the first active nest found of the year and it’s fair to say that I’m usually in the running, poking about in gorse from the end of February for nascent Long-tailed Tit nests or scouring the rivers and reedbeds for early Mallard and Moorhen clutches. The ideal target species would be Crossbill, our earliest breeding songbird, were it not for the fact that to nests right at the top of tall pine trees and I don’t exactly have the best head for heights (or the physique for climbing, these days).

Spot the nest

This year, however, I have been kicked into touch by BTO Press Officer Paul Stancliffe, who located the first Thetford nest of 2013 before I’ve even started looking. On 19th January, amidst the snow covered wastelands of the town centre, Paul spotted a Collared Dove sitting on a nest lodged at the top of a telegraph pole. The bird was still sitting the next day, and on the 22nd he was able to see into the uncovered nest from his upstairs bedroom window, glimpsing the top of at least one egg. It is now the 24th and the bird is still incubating in the sub-zero temperatures.

First nest record of the year for Thetford

Collared Doves are extremely opportunistic breeders. Data from the Nest Record Scheme show that nesting has been recorded in all months of the year (sample size c. 4,200 records). The peak month in terms of clutch initiation (the laying of the first egg) is April (Figure 1), and the main season is typically from March to July. This is earlier than Woodpigeon which again can be found nesting in most months, but exhibits a peak in laying between July and September.

Figure 1

The current cold snap doesn’t really seem to present much of an opportunity, however, and I fear that the outcome of this attempt is unlikely to be positive. We shall continue monitoring their progress to find out.

Dave Leech

Eggstremely long season

The breeding season starts in earnest in March, you might expect that by the beginning of August, most species would have finished nesting, giving both parents and their offspring time to grow or replace feathers and accumulate fat reserves in preparation for long migratory journeys or harsh winter conditions in the UK. However, volunteers taking part in the Nest Record Scheme are still reporting active nests of many species. It has been a terrible breeding season, with ringers catching very few young birds at Constant Effort Sites and migration hotspots, so these late broods could provide a vital boost to juvenile numbers at the eleventh hour.

After recent flooding destroyed the majority of breeding attempts, we thought that the Reed Warblers at our CES site in Norfolk would give up and move south, but 50 pairs were able lay one more clutch of eggs in a last ditch attempt to make their 9,000km round trip to Africa more worthwhile. The latest chicks will not be leaving the nest until the 26th August.

Yellowhammer

Many nest recorders still have Swallow and House Martin chicks to ring, with young broods reported this week by observers in North Yorkshire, Cumbria and Suffolk and birds sitting on eggs in East Lothian, Dorset and Devon, the latter close to a pair of Spotted Flycatchers with young still in the nest. Some resident species are still nesting too, including an incubating Yellowhammer found in Cambridgeshire on Tuesday, Reed Bunting and Tree Sparrow broods soon to be ringed in Suffolk and Meadow Pipit, Stonechat, Dartford Warbler and Linnet with large chicks this week in Devon.

 

Reed Warbler

Add to this the traditional late nesters such as Woodpigeon, for which the peak of the nesting season occurs in August and September, Collared Dove, Stock Dove, Barn Owl, Moorhen and Coot, and there are still many more nest recording opportunities to be had in 2012! Contact the Nest Records Organiser for more information.

Thanks to Dave Leech for the photos