NATURE NOTES NO. 7
Tracking the Cuckoo's Decline
Over my years in the Sterridge Valley, I have often been asked why cuckoos are now rarely heard and, much less likely, seen. Time was when the first cuckoo of spring would be reported in TheTimes newspaper. Once a common sight in the UK, their numbers have dwindled to the extent that the cuckoo is now a Red-listed Bird of Conservation Concern. Surveys over the past 25 years have revealed that we have lost over half of our breeding cuckoos.
In efforts to find out why they are declining, the British Trust for Ornithology (BTO) began satellite-tagging cuckoos in 2011.This enabled them to be tracked from their breeding areas in the UK to wintering grounds in the Congolese rainforests of Africa. A lot of vital knowledge has since been gained, such as how the different routes taken to and from the UK year on year by individual cuckoos are linked to declines, and some of the pressures they face on migration. It has also revealed that they are in the UK for a surprisingly short time (most only arrive in late April but start leaving again as early as June).
Breeding season surveys have shown, too, that Cuckoos are doing better in some areas of the country than in others, the decline in England being greater than in Scotland and Wales. Why this should be is not clear, so a greater understanding of all aspects of the cuckoo's annual cycle is needed in order to get a better idea of the factors driving the decline.
Male Cuckoo, Lundy, May 2021 [photo by Dean Jones]
Whilst much has been learned, much remains to be discovered.Researchers are now looking closely at how dependent cuckoos are on - and how much their migration is linked to - the rains of the weather system known as the Inter Tropical Convergence Zone (ITCZ) as the birds move out of their wintering areas and begin their long journey back to the UK via West Africa.
At present the study has focused on male cuckoos as they are larger than females and better able to carry the 5-gram tags more easily. The tags are solar-powered, transmitting for 10 hours and then going into 'sleep' mode for 48 hours to allow the solar panel to recharge the battery. Once smaller tags are available, females and juvenile birds will also be ringed, yielding new insights into how their migrations differ from the males tracked so far.
In addition, identifying areas of importance for wintering cuckoos will allow study of pressures there which may throw more light on the losses of British cuckoos.
You can read more on the BTO's website (www.bto.org) by entering 'Cuckoo Tracking Project' in the search box on the home page.
NATURE NOTES NO. 6
Meadow Magic - with Tim Davis
What I have learnt over the 20 years that we have lived at Harpers Mill is that a wildflower meadow is a wondrous thing. It takes time and patience to create a meadow from scratch but the results are hugely satisfying and the enjoyment derived from it increases year on year. For example, a few years ago the first southern marsh-orchid appeared, most likely from long-dormant seed waiting for the right conditions. Their number has steadily increased until this year there were 75, mostly in the meadow but others appearing in other parts of the garden nearby. Twayblade was another orchid that popped up one year, but in its second year it got nibbled early on, probably by slugs, and hasn't been seen since. Common spotted orchid is another that suddenly appeared in a smaller meadow area and has flowered twice in recent years. Then, in late June this year, we made an astonishing discovery.
There, standing tall (over a foot high) and 'hidden in plain sight' amongst the ox-eye daisies and meadow grasses was a greater butterfly orchid (Platanthera chlorantha) coming into flower. Mesmerised, we stood transfixed, hardly able to believe what we were looking at. Records of the species in the two most recent 'Floras' describing the plant life of Devon (published in 1984 and 2016) show how rare it is: just two North Devon records in the earlier Flora and only three more since then. The entry in the 2016 Flora describes it as 'occasional' and Near Threatened on the British Red List, occurring in 'well drained, usually, base-rich or calcareous soils in woodland, commons and meadows, pastures and roadsides, but very rare in North Devon'.
If you haven't yet discovered the joy of a meadow, big or small, and would like to devote a patch of your garden towards creating one, visit Plantlife's website (www.plantlife.org.uk) and go to the blog page entitled 'What is a meadow, why do meadows matter and how can you make one?'. Not only will you be adding variety to your garden, but also helping to stem the loss of insects, which pollinate many of our fruits, flowers and vegetables, and also help break down and dispose of wastes, dead animals and plant material.
Such excitements for us over the years have extended from birds to plants and more recently, especially during the periods of pandemic-induced lockdown, insect life. Of three new discoveries during the last month (including on the morning I wrote this article!) one, of a tiny fly, occurred in our kitchen. It was a mere 5mm long but with longer wings which it was constantly waving around - hence known colloquially as a trembling-wing or flutter fly; its scientific name is Palloptera muliebris.
The second was a western bee-fly (Bombylius canescens) which we photographed nectaring on rockrose. This turned out to be another fairly scarce species for North Devon, with currently fewer than 40 records for our region on the National Biodiversity Network (NBN) Atlas. And the third new fly - a 3mm-long small semaphore fly (Rivellia syngenesiae) - we found, would you believe, feeding on the stem of the butterfly orchid! There are four Devon records on the NBN Atlas, just one previous record shown for North Devon.
Whatever will we discover next?!
Greater butterfly-orchid and (top to bottom) trembling-wing fly, western bee-fly and small semaphore fly
Photos: Tim Davis and Tim Jones
Life at the Bird Feeders and in the Nestboxes - with Tim Davis
Several years ago we bought the section of Smythen Wood that cloaks the steep slope above our house. We quickly set about making and putting up more nestboxes to add to the five already in the garden. This year the number has grown to 32, four of them now in the small nature reserve we co-own [with John and Fenella Boxall] that runs alongside the lower part of the hill up to Smythen. We feed birds [sunflower hearts and suet] year-round, such that during the autumn, winter and the approach of spring the garden supports a large number and variety of birds. Blue and Great Tits abound, with smaller numbers of Long-tailed Tits, Chaffinches and Goldfinches, along with year-round territorial Marsh Tits, Nuthatches and Great Spotted Woodpeckers and, usually arriving in late February or March, several pairs of Siskins which in recent years have stayed to nest in the surrounding woods. Siskins will also sit tight on the feeders, spilling seed out as they feast, often regardless of our close presence. A great joy is to watch and hear male Siskins song-flighting bat-like around the garden.
Somewhat mystifyingly, two absentees from our regular garden guests are Greenfinches and House Sparrows. Both are present up at Smythen [Greenfinches though now in greatly reduced numbers due to the outbreak of disease that has decimated their population UK-wide] but sightings in our garden have been few and very far apart over our 20 years at Harpers Mill.
Hangers-on [though not literally!] picking up what falls onto the ground from the feeders, are Blackbirds, Dunnocks, Woodpigeons [one pair had a well-grown chick in a yew hedge in early February this year], Carrion Crows, Magpies and Jays. Pheasants too suddenly started appearing some ten years ago and now nest, with varying degrees of success, in the nearby field margins. Witnessing what just a few can do to a garden and wildlife, especially larger insects and newly emerging froglets and toadlets as they spread out around the garden, makes the mind boggle at the impact of 45 million or more released annually in the UK for recreational shooting.
A regular visitor to the feeders this year has been a male Sparrowhawk. If its first pass at break-neck speed in search of a meal has failed, it will sit on the crossbar of the feeding station, sometimes for minutes on end, its wild glinting eyes constantly scanning the nearby bushes for a potential victim. Meanwhile an immature Buzzard is more interested in what it can pick up from the ponds, usually a frog or a toad, or at this time of year as they leave the ponds after breeding, Palmate Newts. Of late, two Grey Herons have started to drop in at the ponds. They won't find any fish but there's plenty of other wetland life in there to whet [wet?!] their appetites.
In 2020, 21 of our nestboxes were occupied, 16 by Blue Tits and 5 by Great Tits. This year the uptake has been 22 boxes, with 17 used by Blue Tits and 4 by Great Tits, and for just the second time, one pair of Nuthatches. We monitor the boxes for the British Trust for Ornithology's Nest Record Scheme, and a fully qualified bird-ringing friend comes over to ring the nestlings when they are big enough. At the time of writing, we don't yet know the outcomes for each of the boxes, but there is no doubt that the success rate, given the cold, very dry April and prolonged cool, rainy spell of mid-May will have taken a toll as adults struggled to keep chicks warm and fed. Sadly, at the time of writing, the Nuthatches have lost their four young likely due to the poor weather.
A regular task is cleaning the seed and suet feeders to prevent disease, while the clearing out and disinfecting of the nestboxes is a once-a-year job after the breeding season is over. Boxes that aren't occupied by breeding birds will more often than not be used for overnight roosting, with a consequent accumulation of droppings which need removing. Replacing old or rotting boxes is another annual task, but the actual making of the boxes provides hours of patient pleasure, especially on a gloomy, wet or windy winter's day.
One of the garden boxes this year occupied by Great Tits
A clutch of Blue Tit eggs . . .
and five Blue Tit nestlings waiting for the next meal
Photos: Tim Davis
NATURE NOTES NO. 4 - OIL BEETLES OUT AND ABOUT
With Tim Davis
This little creature - a male Violet Oil Beetle (Meloe violaceus, pictured left) - the first of the year, was crawling through grass in the garden on 9th March. The species is commonest in meadows and woodland in south-west England, with patches of distribution elsewhere mostly in western and northern Britain. It is flightless and can be found between March and June, in gardens usually on grassy tracks - which over the years have helped the beetle to spread to all corners of our wild garden.
The female Violet Oil Beetle (pictured right) is considerably larger (up to 32mm in length) than the male and has a distinctly plump appearance, laying several thousand eggs in a burrow. The resulting maggot-like larvae climb up to flowerheads and attach themselves, using hook-like forelegs, to ground-nesting female solitary bees. Once in the bee's nest burrow the larva feed on the bee's egg and pollen store. The larva pupates and spends the winter in the burrow, hatching and emerging as an adult beetle in the following spring. The beetle gets its name from the pungent oily liquid which it uses to defend itself.
With the loss of wildflower-rich grassland and heathland from large parts of our countryside, and with those habitats three now extinct species of oil beetle, seven different species of oil beetle remain in Britain and Ireland, the most common being the visually identical Black Oil Beetle, which also occurs in North Devon, including Lundy where it has been found in recent years as insect recording has become more popular. How can you tell the two species apart? Violet Oil Beetle has an indented thorax, while its cousin has a straight base to the thorax - the part between the head and the body in the photographs. The beetle will quite happily climb onto a hand if you're careful, allowing close-up views - but even then, a magnifying glass would help!
Photos: Tim Davis and Tim Jones
Watch out for . . .
. . . the return of our spring migrants. Two of the first birds [both warblers] to return from winters spent in West Africa or the Mediterranean are Chiffchaff and Blackcap, both usually arriving from the second half of March into early April. The males of both species will very quickly set about establishing breeding territories in scrubby areas of blackthorn and bramble or thickets, often singing tucked away in branches of hazel, willow or hawthorn. If you are not already familiar with their songs, you can tune into them by visiting www.xeno-canto.org and typing their international English names (Eurasian Blackcap and Common Chiffchaff) into the search facility. Another useful tool which I always carry with me is the Collins Bird Guide app, available for both iPhone and android mobiles.
Chiffchaff [by Dean Jones]
Male Blackcap [by Richard Campey]
Recycled Wellies! Thanks to all who dropped off old wellington boots at Harpers Mill. Their upperparts will be put to good use as (waterproof)] hinges for nestbox lids. More welcome at any time!
NATURE NOTES NO. 3 - WINTER DAYS & EARLY BIRD SONG
With Tim Davis
With woodland on the slopes either side of our house at the upper end of the Sterridge Valley, and numerous berry-bearing trees and shrubs as well as regularly filled seed and suet feeders around the garden, we are blessed with a wide variety of birds. One of the great joys of midwinter is the 'start-up' of bird song, nearly always kicked off in the second half of December by Great Tits and Song Thrushes, all keen to establish territories well before the onset of nesting as winter gives way to spring - which now happens two to three weeks earlier than when I was growing up in the 1960s.
By February - assuming we aren't hit by another 'Beast from the East' - Blue, Coal and Marsh Tits, Woodpigeons, Blackbirds, Chaffinches, Siskins, Wrens, Dunnocks, Goldcrests, Treecreepers and Nuthatches will also be singing in the surrounding woodland, along with one of the shyest and most elusive of British birds, Mistle Thrush, their strident, ringing song delivered in long bursts from the very tops of the tallest trees. Last year three pairs were 'broadcasting' their territories in Woolscott Cleave (two) and Smythen Wood. While Blackbirds are renowned early breeders, some even before the old year turns in milder winters, Ravens are amongst the first to be feeding young in the nest. Already in very early January, as I write this, our local pair are back on territory, while on sunny days we have watched Buzzards and Sparrowhawks begin their aerial displays.
If we find ourselves in lockdown again this spring, there's plenty of nature close to home in which to breathe and lose yourself for regular mind-restoring periods.
False Blister Beetle (photo: Tim Davis)
Tim J and I found this little fellow (about 1cm long but sadly dead) caught in a strand of a spider's web above the door to our cottage on 30th December. One of a family of pollen-feeding beetles commonly called False Blister Beetles, this nationally scarce species, Oedemera femoralis, is nocturnal and feeds mainly on ivy and sallow from April to September. The Devon beetle recorder, Martin Luff, tells me that there are currently 40 records for the county, but this is the first for North Devon. The find was a reminder that during the past year, due in large part to lockdown (no work and no travel!) and the warm and sunny spring and early summer, we added all sorts of insect species to our garden list. To find this one on the penultimate day of the year was something of the icing on top of the Christmas cake!
If you want to get into insects, one of the best photographic guides is Paul D. Brock's A comprehensive guide to Insects of Britain & Ireland, a new and expanded edition of which was published in 2019 by Pisces Publications. We purchased our copy online at www.nhbs.com, price £28.95.
Wanted: old wellies!
If you have old, worn-out or unwanted wellington boots, I should be delighted to have them - the upperparts make perfect hinges for nest boxes! All you need do is drop them off either at the village shop for me to collect, or put them under the post box at Harpers Mill. Many thanks.
NATURE NOTES NO. 2 - JAYS
with Tim Davis
Writing this in the dying days of October, with autumn well and truly under way and the annual rain of leaves gathering pace, jays have suddenly become more evident in our Sterridge Valley garden. Normally a noisy but shy, almost reclusive bird of mainly broadleaf, but also coniferous, woodland, these large colourful members of the crow family take advantage of the abundance of food that nearby gardens have to offer. They are opportunists, their omnivorous diet consisting mainly of seeds, nuts and berries, but insects, small mammals such as voles and bats, and eggs and nestling birds also feature on the menu.
The jay's scientific name, Garrulus glandarius, is as beautifully descriptive as the bird itself, the former meaning noisy or chattering, and the latter referring to acorns, the food with which it is most associated - in particular for its habit of burying acorns, as well as hazelnuts and beech mast.
For a large bird, similar in size to a rook or carrion crow, jays can be surprisingly difficult to see well, rarely moving far from cover. As Richard Campey's striking photo shows, the jay's plumage is pinkish, the wings black and white with a panel of distinctive kingfisher-blue feathers. The head has a pale crown with black streaks and a well-defined black !moustachial' stripe. Usually it is the raucous call or the flash of a broad white rump that draws the eye.
This autumn we have enjoyed watching the antics of up to four birds moving around the garden, collecting nuts and burying them in the meadow for retrieval later in the winter. That not every acorn or hazelnut cached is later collected and eaten is evident from the numerous oak and hazel seedlings that appear across the meadow every spring. The realisation dawns that the meadow, if not managed as such for its wildflowers, butterflies and other insects, would quite quickly become a woodland. The important role that jays play in woodland ecology thus also becomes apparent.
Jays occur across most of the UK, with the exception of northern Scotland. The current breeding population is estimated at 170,000 pairs [www.bto.org/birdtrends]. In some years, typically when a good breeding season is followed by a poor autumn for nuts and berries, large flocks may roam nomadically, covering great distances in search of food.
Photo by Richard Campey
NATURE NOTES NO. 1 - SABRE WASP
with Tim Davis
While walking the woodland trails of Woolscott Cleave during 'lockdown spring', it wasn't only birds that I was enjoying watching and listening to. Insect life too holds much fascination, though this often involves training one's eyes to look downwards rather than upwards!
One particularly startling - and beautiful - creature I came across in late June was a female Sabre Wasp (or Giant Ichneumon) Rhyssa persuasoria (pictured). The largest ichneumon in Britain - females can grow to 4 centimetres in length, plus another 4 cm for the needle-like ovipositor - it is also readily identified by the white spots along its black abdomen and its orange-red legs. Despite its fearsome appearance, it is completely harmless to humans and pets.
Adults can be encountered mainly in July and August, along woodland paths and clearings. They feed on sugars and starch obtained from honeydew or pine needles. Far from being a 'stinger', the ovipositor is used to drill deep into wood and lay eggs on the larvae of other insects, such as Wood Wasps, living within the timber, which become a food supply. The Sabre Wasp's larvae overwinter in the wood, pupating in spring and emerging as adults.
Sabre Wasps occur widely across Britain in mixed and coniferous woodland, such as Woolscott Cleave. Sadly, the specimen I encountered had evidently been in a tussle with a would-be predator, having lost several of its legs.
WHERE HAVE OUR GREENFINCHES GONE?
I sometimes get asked why Greenfinches have disappeared from many of our gardens. Certainly in the 12 years that Tim Jones and I have lived at Harpers Mill we have noticed fewer Greenfinches in and around the village, as well as at Smythen Farm. For some reason Greenfinches are only infrequent visitors to our garden, despite lots of apparently suitable habitat. Among several diseases which affect birds, one in particular, trichomonosis, has been the principal cause of the decline in Greenfinches, and to a lesser extent Chaffinches.
Trichomonosis typically causes disease at the back of the throat and in the gullet. Affected birds show signs of general illness, such as lethargy and fluffed-up plumage, and may show difficulty in swallowing or laboured breathing. Some individuals may have wet plumage around the bill and drool saliva or regurgitate food that they cannot swallow. In some cases, swelling of the neck may be evident. The disease may progress over several days or even weeks. It does not affect humans or other mammals.
An item on the British Trust for Ornithology's website in mid-September reported new research that brings our understanding of the disease outbreak up to date.
The widespread emergence of trichomonosis in 2006 has resulted in a substantial decline in the Greenfinch breeding population. The new research demonstrates that mass mortality in Greenfinches continued in 2007-2009 at a rate of more than 7 per cent of the population each year, but with a shifting geographical distribution across the UK. In this time the population of Greenfinches in Great Britain fell from some 4.3 million to about 2.8 million birds. It appears that the disease jumped from pigeons or doves to finches, but quite why Greenfinches suffered more than other small birds remains unknown.
For more information on trichomonosis and other bird diseases, visit the BTO website at www.bto.org and follow these links: home > volunteer-surveys > garden birdwatch > gardens & wildlife > birds > disease. This will take you to a page on 'Disease and garden birds'. Here you will find advice on what you can do to look after your garden birds, especially the need to keep feeders clean. If you would like to report finding dead garden birds or signs of disease in garden birds, there is also an online reporting form.
Greenfinch © Mike Langman
Most Berrynarbor residents will be familiar with Swifts,
which arrive in the
In addition, their habit of [literally] screaming at high speed low over rooftops, often in small parties, especially towards dusk, makes them unmissable to anyone out and about the village.
Swifts are the most aerial of birds. They feed on flying insects and never perch on wires like Swallows. In fact, once a young Swift has fledged, it is unlikely to land anywhere until it reaches maturity and looks for a nest site of its own three or four years later. But finding that desirable location in which to nest is becoming increasingly hard for Swifts. Their nesting places, in the eaves of rooftops and older buildings with cavities, such as the Manor Hall, are disappearing as buildings are modernised and access to roof spaces blocked up.
Ten years ago, when Tim Jones and I came to live in the
Now, we have a chance to help them. As some of you may have seen in a recent issue of the North Devon Journal, a conservation project has been launched within the North Devon Area of Outstanding Natural Beauty
[AONB] to help Swifts. With funding from the North Devon AONB, researcher Greg Ebdon has been visiting villages within the AONB to record the numbers of Swifts and the location of nest sites, as well as looking for appropriate sites where specially constructed Swift nestboxes can be put up. Four nestboxes have already been installed at St Helen's Church in Abbotsham, for example.
If you would like to encourage Swifts to nest within the eaves of your house or on the wall under the eaves, you can obtain a nestbox from Greg by contacting him on firstname.lastname@example.org. Note that because Swifts need height to take off, single-storey buildings are not suitable; nest sites are usually located at least six metres from the ground. Once a nestbox has been installed, to stop other birds using it, the opening can be blocked until the Swifts return. If you are unsure whether your house is suitable, I should be happy to give advice. You can contact me on 882965 [daytime] or 883807 [evenings/weekends] or at email@example.com.
For more information on Swifts, including a short video and a sound recording of their calls, visit www.rspb.org.uk/wildlife/birdguide/name/s/swift.
Artwork by Mike Langman [www.mikelangman.co.uk]
THE BIRDS OF LUNDY
some ten miles off the nearest point on the
- that is the Tims of Harpers Mill - have been visiting Lundy for more than 50
years between us. The idea to write a
new book on the island's birds first struck in 1999. Initially we contacted former Lundy Warden
Nick Dymond to ask if he had any plans to update his own book on Lundy's birds,
published by Devon Bird Watching & Preservation Society in 1980. At that stage Nick was part way through
revising the text but, as he put it, 'running out of steam' and with many other
things on his plate. Nick kindly forwarded his notes, giving us a
great starting point. In the intervening
years, as well as scouring every Lundy Field Society (LFS) Annual Report, Devon Bird Report and the surviving LFS logbooks
from the island, we have researched every scrap of information we could find.
This included a fascinating visit to the Alexander Ornithological Library in
of the work has been done in our spare time, but, conscious of the years
passing by, we began to step on the accelerator in 2005 until finally, in
February this year, we completed the manuscript. Since
then we've been polishing it and adding bird records for 2007. We took the book to the printer, Short Run
Press Limited of
Birds of Lundy itself fledged on 29th September at a launch at RM
Young (Bookseller) in
The goals we set ourselves in preparing the book were:
- To produce an up-to-date account of the ornithology of Lundy, with a review of historical records and an account of all bird species that have occurred on the island since the founding of the LFS in 1946 and the commencement of daily records in 1947.
- To raise awareness of the Devon Bird Watching & Preservation Society and the Lundy Field Society and promote their roles in the research and conservation of birds and the natural environment, both in Devon and on Lundy.
- To invest any proceeds made from sales of the book in bird-related conservation work on Lundy.
- To promote awareness and appreciation of Lundy's conservation value and its importance as a prime 'ecotourism' destination and birdwatching venue.
- To stimulate enhanced recording of birds and other wildlife on Lundy.
Whether we succeed in all of these objectives only time will tell. The immediate result is a detailed account of the 317 species that currently make up the Lundy bird list, plus a further 36 species which for various reasons do not qualify for the full list. Internationally renowned biologist Hugh Boyd, who began his ornithological career as LFS Warden in 1948/49, has penned the book's foreword. [Health permitting, Hugh will be staying with us on the island this October.]
well as writing the book, we also published it on behalf of Devon Birds and the
LFS. Both organisations contributed
grants to cover the printing costs, and we are grateful also to several other
individuals and organisations that have supported the book financially. All are acknowledged within the books 319
pages, which are enlivened by 20 colour photographs and more than 100 line
For more information visit www.birdsoflundy.org.uk or contact us on 882965 [daytime] or 883807 [evenings and weekends].
you have thought about going to Lundy but have yet to do so, we hope that The Birds of Lundy might inspire you to
step onto the island boat, MS Oldenburg, and off at the other end onto the
Tim Davis & Tim Jones