Birds in UK Vineyards
Click here to read an introduction to the Birds in UK Vineyards project.
Update: October 2022 – Bird friendly wine-drinking: preliminary results poster
In the summer, I presented a poster summarising some of the results of 2021 bird monitoring at two conferences at the University of East Anglia and the Norwich Research Park and had the opportunity to talk to fellow researchers about British vineyards. In this blog post, I’d like to share these results with you.
I presented the results of 146 bird observations performed across the 2021 grape-growing season across 22 English vineyards. I was interested in understanding how the time in the season, going from budding in April to harvest in October, affected vineyard bird communities, and also in comparing organic and non-organic vineyards.
Across all vineyards, I recorded 59 bird species, 13 of which are Red-listed by the RSPB. Bird communities can be summarised in terms of the overall number of bird species present (Bird Richness), and the number of individuals across all bird species (Bird Abundance). Firstly, considering richness, we can see that there is a small increase in the later season compared to April, and this is more pronounced in organic vineyards, which also host marginally higher bird richness than non-organic vineyards. Turning to bird abundance, we can see big increases throughout the season, with twice as many birds being recorded at harvest in October than in April. Some of these differences can be explained by birds’ breeding behaviour as by early summer, birds would have fledged and I was noticing groups of adults with chicks feeding within vineyards by June, which can explain the increase in bird numbers.
What’s really interesting is to look more closely at the birds that make up the communities in British vineyards and to see how these vary across the season and between organic and non-organic vineyards. One way of doing this is to characterise birds by the food they eat, which allows us to broadly split birds into those that feed on insects (insectivores) and blue tits are a prime example; those that mostly feed on seeds and grains (granivores), including goldfinches; and those with varied diets, often composed of insects, seeds and fruits (omnivores), such as blackbirds. Lastly, we can consider bird species that are known to feed on fruits, including grapes, which includes starlings, blackbirds or pheasants.
There were some interesting patterns in the bird community composition across the vineyards. The richness of birds was highest among insectivorous and grape-eating species, followed by omnivorous and granivorous species. Whilst vineyards hosted a fair few insectivorous species, their numbers were low, and the most abundant groups were grape-eating species. The most significant changes in bird composition were observed between spring / summer and the harvest, when the abundance of omnivorous birds, including grape eaters, at least doubled, which won’t be much of a surprise to those of you who experience problems with birds eating the grapes at harvest.
There weren’t any profound differences in the bird community composition between organic and non-organic vineyards. The richness and abundance of omnivorous species, including grape-eaters did appear slightly higher in organic vineyards, though these differences weren’t strong or consistent across the surveyed sites. Though there were some small differences in the richness and abundance of insectivorous and granivorous species between vineyards managed organically and non-organically, these were small and inconsistent across the three survey periods.
Bird richness, abundance and community make up will be affected by local and landscape habitat features (hedgerows, woodland presence, ground cover management etc.), thus there’s a lot more to explain and explore. I’ve just finished doing the second year of bird surveys and the extra data will help in further understanding the factors that most affect bird communities across British vineyards, and in informing how vineyards can be managed to deliver bird conservation, whilst ensuring business prosperity.
All photos and graphics by Natalia Zielonka.
Update: February 2022 – Birds in English vineyards: early results
If you’ve been following my blogs, you’ll know that I’ve been visiting 20 English vineyards in search for birds, as part of a project trying to understand how vineyard management and the surrounding landscape impact and shape the local bird communities. After over 17 hours of surveys and some time staring at rows of data on my computer screen, I’m delighted to share some results about the bird communities that live across English vineyards.
Altogether, 57 bird species were sighted across the 20 study vineyards. Some of the most common species will be a familiar sight to many of you, such as Wood Pigeons, Crows, Blackbirds or Blue tits, which were recorded on every vineyard I visited. Whether these stick to the hedges and trees around the borders of your vineyard, or hop in between the vines in search for food, these birds have made the vineyards into their homes. Other commonly sighted species included Goldfinches and Linnets, two beautiful finch species, which often travel in flocks, a dozen to over a hundred in size. I always feel joy observing these, and I spent hours observing groups of Linnets and Goldfinches sitting on trellis wires before flying down to the ground to feed among Common Groundsel or landing on the mature Thistle and Teasel plants. It was a delight watching a pair of adult Goldfinches bring their freshly-fledged chicks to feed at the base of the vines in June; the noisy family really made the vineyard come alive.
Some of you may be less fond of two of the common species – the Pheasants and Starlings. Pheasants creeping and ducking under the vines, in search for seeds and invertebrates on the ground, may be a common but an unwelcome sight, as they’re often unable to resist eating a grape or two on their way. When it comes to Starlings, you may often hear them among the vines before seeing them, but if you’re lucky you may catch a glimpse of a breath-taking murmuration against the sunset. Starlings travel and feed in groups, sometimes a hundred strong, so it’s no surprise that these made it to the list of the top-nine most commonly sighted birds in vineyards. What is interesting though, is that despite being one of the most abundant species, they were only recorded in 11 of the vineyards. This is an apt illustration of their decline, as their populations have fallen by 66% since 1970s, and their distribution is now much more patchy.
Birds around the world are declining, often due to increasing pressures from habitat loss caused by urbanisation, agricultural expansion and unsustainable land management practices. We live in a changing world and this means that birds (as well as other species) need to be regularly monitored to understand if their populations are declining or expanding. This is used to inform their conservation importance, and all species are given a conservation status: Green, Amber and Red, where the Red list includes species that require urgent conservation action, as these species are:
- Globally threatened
- Have experienced historical population declines in the UK in the 19th and 20th Centuries
- Their UK breeding population has declined by at least 50% in the last 25 years
- The size of their UK breeding range has declined by at least 50% in the last 25 years
Birds of Conservation Concern 5 report was compiled in 2021 by a partnership of UK’s leading bird conservation and monitoring organisations, including the RSPB, BTO and Game & Wildlife Conservation Trust among others. The 2021 Red list is nearly double its length in 1996, when the first report was published. As Andrew Stanbury, RSPB’s Conservation Scientist, put it “the results […] are sobering.”
The purpose of the Red List is to inform conservation priorities – it helps decide which species should receive our limited conservation funding, time and effort. This is the first step on the road to recovery, as we know that conservation efforts can work. Among the many species that are on a downward spiral, there are some which have changed their statuses from Red to Amber, and Amber to Green, as their populations have been increasing and stabilising.
There are 70 species on the Red List, and 13 of these species were sighted in English vineyards. I think that’s a great indication that English vineyards can be great habitats for some of the most threatened UK species, and are also important for their conservation.
Among these Red listed species sighted in vineyards are a few members of the finch family: the House Sparrow, Redpoll, Greenfinch and the Linnet. Finches frequently feed on seeds and glean insects off foliage in the breeding season. A number of species are frequent garden visitors, some stick to farmland habitats, whilst others prefer woodlands. The reasons for finch decline vary between the species, but unsustainable farmland practices such as hedgerow removal, loss of winter stubble, and improved seed maintenance around grain stores (and thus, fewer leftover seeds) are thought to have driven House Sparrow population declines. The driver of Greenfinch decline is thought to be the increased feeding of birds by people, as poor maintenance of bird feeders leads to the spread trichomonosis, a disease caused by a parasite that affects the throat and gullet of birds. It often causes death as infected birds have difficulty swallowing, and eventually breathing. Trichomonosis affects several garden birds (e.g. House Sparrows, Great tits), as well as pigeons and birds of prey, and it can easily spread through shared water and food. To help limit its spread, feeding stations for birds should be regularly cleaned.
An increasing number of Red-listed species are insect-feeders, which are suffering declines as they struggle to find enough food to survive and to feed chicks. Swifts are one such example. These are migratory birds that visit the UK to breed in the summer months. They are impressive aerial feeders and long-distance migrants, which rely on flying insects to raise chicks and to fuel their journey to the south of the Sahara. Maintaining rich insect habitat and limiting pesticide use can really help to conserve Swifts, as well as Swallows and House Martins, at your vineyard.
If you’d like to find out more about what you can do to support the bird communities at your vineyard, please visit the RSPB and BTO pages which provide some great general advice.
All photos and graphics by Natalia Zielonka.
Update: January 2022 – Wine and birds: a double win for your wellbeing
Many wine drinkers would probably agree that a good glass (or bottle) of wine enhances their mood and helps them de-stress. However, that’s not the only way in which vineyards could be contributing to your mental wellbeing, as birdsong could be having a similar effect.
It’s long been known that spending time in nature benefits our wellbeing, physical and mental health, but still, the full significance of this wasn’t realised by many until the pandemic, when much of what we enjoyed – friends, holidays and events – were taken away from us. This has sparked scientists to consider the impact nature has on human wellbeing. In an experimental manipulation along nature trails in Colorado, researchers manipulated playing birdsong through speakers before asking walkers about their wellbeing. Walkers who heard the birdsong through the speakers reported increased feelings of wellbeing, despite not being consciously aware that more ‘birds’ were present. Incredibly, these researchers showed that just a few minutes of birdsong boosted human wellbeing.
Not all songs are created equal, as prior experiences of certain birds can alter how different bird songs affect us. In a series of scientific studies, Dr Eleanor Ratcliffe from the University of Surrey found that bird song offered relief from mental fatigue and stress to British study participants, but the effect on individual participants wasn’t the same. For example, one participant found enjoyment in the call of a Wood pigeon (a bird that’s not famous for its call) as the call reminded them of hot summers from the childhood. This suggests that bird calls can help us notice things around us and connect with the environment and ourselves, which will help us become more mindful (a practice that has been linked to reduced stress and better wellbeing).
However, our landscapes are being silenced. Europe has lost almost a fifth of its birds since 1980s as we have 600 million fewer birds in Europe now than we did 40 years ago. This, unsurprisingly will affect our soundscapes (acoustic landscapes), as shown by a study led by researchers at the University of East Anglia who found that bird declines led to the bird chorus becoming quieter and less varied. As biodiversity is predicted to further decline, this may have widespread consequences for human wellbeing.
Many vineyard managers are well aware that their vineyards provide more than wine, though as vineyards are relatively new developments in parts of England, they can be perceived as unwelcome developments by the local residents, often over the fear of damaging nature and the local landscapes. Perhaps a win-win solution would be for vineyards to protect birds on their land, helping to slow down the decline in bird populations and turn the volume up of their soundscapes. Nature may repay you and your visitors with boosted mental wellbeing and reduced stress.
Biodiversity protection is strongly encouraged by the Sustainable Wines of Great Britain scheme (SWGB), and there are many things that all vineyard managers could be doing to encourage biodiversity, including birds. The RSPB (Royal Society for the Protection of Birds) offers great general advice on how you can protect biodiversity on your land, and some more details on managing habitats is available here.
And if you feel inspired and would like to listen to some bird song, here is a really handy guide to identifying some of the most common bird songs from the Natural History Museum.
All photos by Natalia Zielonka.
Research papers used:
- More than wine: Cultural ecosystem services in vineyard landscapes in England and California: https://doi.org/10.1016/j.ecolecon.2016.01.013
- Bird population declines and species turnover are changing the acoustic properties of spring soundscapes: https://doi.org/10.1038/s41467-021-26488-1
- Abundance decline in the avifauna of the European Union reveals cross-continental similarities in biodiversity change: https://doi.org/10.1002/ece3.8282
- Predicting the Perceived Restorative Potential of Bird Sounds Through Acoustics and Aesthetics: https://doi.org/10.1177/0013916518806952
- The phantom chorus: birdsong boosts human well-being in protected areas: https://doi.org/10.1098/rspb.2020.1811
Update: January 2022 – When birds have a sweet tooth for grapes
The delightful and the hungry
A shorter version of this article is available in the December 2021 issue of The Grape Press. To read this, and other issues, please click here.
Whether it’s the melodic song of a Blackbird on a misty autumnal morning, the laugh of a Green Spotted Woodpecker that just burst into a fast flight, or a breath-taking Starling murmuration over a strikingly orange and pink sky, birds certainly bring us lots of joy and help us connect to nature. However, if you’re a winegrower, there may come a time, when birds cause you to lose sleep, as it seemed to be the case in 2021.
Going for the low hanging bunches
Perhaps going less for the alcohol-content and more for the sugar, birds like us seem quite fond of grapes. Across all the grape-growing regions of the world, birds can cause severe economic losses by inflicting severe grape damage. Following the recent UK harvest, I’ve heard from some winegrowers who saw their entire crop of Reichensteiner and 80% of Phoenix end up in the stomachs of these feathery pests rather than in a press. Meanwhile other winegrowers shared their joy of seeing birds in their vineyards and admitted to happily sharing a few percent of the crop with their visitors.
Bird damage to grapes is spatially variable. Numerous studies from the key wine growing regions found greatest bird damage around field edges and being higher near hedges or lone trees. These habitat features act as safety blankets for birds, allowing them to perch quietly and look out for predators before making the short journey to nick a grape or two. This is why it’s been suggested that small and isolated fields that are surrounded by non-crop habitat, such as a woodland, are most susceptible to grape damage from birds.
Birds can shift their dietary preferences throughout the harvest season, making grape damage temporally variable. In South Africa, omnivorous species typically fed on the early ripening grape varieties before switching to insects when these became available. Reports from UK vineyards indicated a similar switch in the diet, as birds were known to suddenly take an apparent dislike to grapes over other food sources. This shift may be linked to changes in the availability of alternative food sources such as wild berries, grass and cereal seeds and insects, or it may indeed be linked to the grape varieties available, as birds prefer red and sweeter castes.
The 2021 harvest season was unusual and challenging, as the limited rays of sunshine made ripening slow, and gave more opportunity for damage as some grapes weren’t harvested until November. This made for an anxious wait as winegrowers vigilantly monitored sugar levels and with each Brix degree up, came more birds which always seemed quicker to know when the sugar levels were right. One winegrower even jokingly said that he doesn’t need to bother using his refractometer when birds were around! This preference of birds for grapes with high sugar content was indeed experimentally demonstrated and taken together with the shift in birds’ dietary preferences in response to changing food availability sheds some light into why the timing of bird damage can be so variable and unpredictable year-on-year.
Vineyards can be bursting with bird life so pinning down the key grape thieves can be difficult, though a few species tend to regularly come up in conversations, namely Starlings, Blackbirds, corvids (e.g. Carrion Crows and Magpies), pigeons and Pheasants. These species are definitely common across UK vineyards, which makes them likely candidates, though caution should be taken blaming the most apparent species as bird losses are not always directly linked to birds’ abundance and relatively-rare species with a sweet tooth have been known to inflict a lot of damage.
A novel approach to identifying the culprits was developed and trialled by scientists in Portuguese vineyards, where motion-triggered cameras were used. The main damage-inflicting species were local species of pigeons, blackbird and House Sparrows, which were most active in the morning and evening. Pigeons and blackbirds, which are larger, were observed taking whole grapes, whilst sparrows pecked holes in grapes, leaving the skin behind.
The location of damage is likely to depend on the species of bird that’s inflicting it. Studies found high occurrence of damage at the highest grape bunches, which are exposed to birds that perch on the vine to take a bite. The species most likely taking this approach are medium to large-sized, such as blackbirds, thrushes and pigeons, meanwhile smaller birds such as finches, tend to take refuge among the leaves and perch on the trellis wire for their snack. During my visits to vineyards, I noticed that many low-hanging bunches take a hard beating, with many having been plucked clean. The most likely species responsible for this is the Pheasant, which a generalist species that readily feeds on grapes, often jumping up to reach the berries. Damage by Pheasants does seem to be closely linked to their abundance as vineyards with neighbouring pheasant release pens tended to be badly hit.
Starlings are interesting because unlike other species, they comfortably feed in the centre of fields, as opposed to the edges, and can quickly eat the whole crop of a small field within hours. This is likely down to their grouping behaviour as Starlings travel in groups that can vary between a dozen to several dozens in size. Safety in numbers means that starlings readily perch in the open on utility wires, directly above grape fields and go down as a group to feed on the grapes. Having said that, some vineyards in the UK have been enjoying murmurations and high yields, meaning that Starlings don’t always mean bad news for your wine.
Bird damage can lead to losses reaching hundreds of Pounds per hectare, thus many methods of controlling bird damage and trying to minimise it have been devised and trialled. There are many control methods, which range from visual (e.g. hawk-kites), auditory (alarm call playbacks) and direct exclusion with netting. All these methods are readily used in UK vineyards, though all come with drawbacks. The simple methods such as eye-spot balloons and hawk-kites have the advantage of being cheap and simple to deploy, but they often lose effectiveness as birds become habituated to them. Exclusion netting is more effective, as it directly prevents birds from accessing the fruits, but it can be costly and laboursome to deploy and collect prior to harvest, especially across large vineyards.
Recent advances in technology have led to the development of more complicated multi-modal devices, such as unmanned aerial vehicles (UAV, also known as drones). Bird psychology has been exploited to build sophisticated and targeted UAV-scarers that are equipped with a loudspeaker emitting distress calls of the main bird pests, and with a taxidermy crow attached beneath to mimic the sight of a bird of prey with a prey item. These UAVs can also be set to mimic flight patterns of birds in attempt to increase their resemblance of real predators. Some studies found these UAVs to be effective for extended periods of time at reducing bird damage caused by larger birds, such as corvids, though they were less effective at deterring smaller passerines.
There’s growing preference for natural farming practices among consumers and pressure to farm with nature in mind. Natural methods of attracting predatory species of birds may do the trick here, as provision of perches for birds of prey in Australian vineyards resulted in 50% reduction in grape damage thanks to lowered foraging activity of birds in the vineyard. Encouraging birds of prey back to UK vineyards may be a nature-friendly and a cost-effective solution that warrants further thought.
A positive outlook
Birds are natural parts of our landscapes and UK vineyards, and a part of me does admire their adaptability to readily adopt grapes into their diets. Of course, it is saddening to see the fruits of one’s labour disappear over a few hours, when there are arguably alternative food resources about. The decision to invest in bird control methods will undoubtedly depend on the degree of damage, which will vary between sites and years. My research across UK vineyards may help to identify some predictors of bird damage and name the key species responsible, which should help to inform targeted and optimised management. In the meantime, I hope that UK winegrowers and birds find a middle ground where everyone can enjoy the beauty of vineyards, and maybe just a few grapes.
Update May 2021 – Getting acquainted with birds in UK vineyards – fieldwork in April 2021
What a wonderful two weeks this has been! Two weeks of lone adventures across the unexplored (by me!) vineyard landscapes filled me with enthusiasm for my project and got me beaming with new-found spring energy. In short, the birds across UK vineyards did not disappoint.
If you’re anything like me then you don’t need much persuading to get out of the house, especially after endless months of home-working, but what I experienced across 18 British vineyards was more than just a walk to the local reserve. These largely unvisited, peaceful landscapes felt serene and dormant, though at the same time teeming with bird life.
In this blog post, I bring you some stories about my encounters with birds on my visits to UK vineyards in April 2021. Before we proceed, I’d like to include a short disclaimer – unlike my previous posts, this blog is a subjective account and whilst, all stories here are accurate, they are cherry-picked to form a memoir of my experience. This post should not be used as basis for statements about bird diversity across vineyards. Data collation and analysis are taking place and later posts over the next 2-3 years will discuss results and findings of this 2-year Birds in UK vineyards Project.
Norfolk & Cambridgeshire
My journey began in the tranquil countryside of East Anglia, where it seemed that the vineyards hadn’t come out of hibernation yet. The vineyards felt still and empty; there was almost an eery feeling lingering in the air. Undeterred and equipped with binoculars around my neck and a notebook held firmly in my hand, I started my bird surveys. Accompanied by the cracking of frosty grass, I began my exploration of the vineyards, slowly walking in-between two, out of hundreds of identically straight and symmetrical vine rows, in search for birds. It wasn’t long before I was alerted by the alarm call of a little robin, which I quickly spotted perching on the wire of the trellis and assessing me with a side glance. I retreated a few steps and patiently watched; the robin seemed more awake than I was, flying off to a nearby hedge, just to bounce back to the trellis wire, on the ground and back again. After a few minutes of this show, my robin friend returned to where I saw it first, paused for just long enough for me to see it had a worm in its mouth, before taking a dive into the upturned ground at the base of the vine. Knowing that spring is definitely here, I smiled and headed further into the vineyard.
As beams of sunshine filled the countryside, all of its residents sprang to life, unveiling the life within UK vineyards. The land filled with drumming and laughing woodpeckers, courting coos of collared doves and woodpigeons and the cheerful chatter of blue and long-tailed tits, all residing in the old oaks along the borders of vineyards. As I roamed across the vineyards, my eyes were drawn to the little buds, which were soon to grow into beautiful grapes. I didn’t have long to contemplate the life of the vine as I was startled by a male muntjac which emerged from a thick hedge on the vineyard edge. We stared at each other, both uncertain of our next move until the buck leaped away. It was clear to me that the vineyards were going to be full of surprises as I was going to delve into their lives. I turned around and left, ready to move on and drive to Kent.
As I drove away from East Anglia, I left flats behind and entered a landscape of gently rolling hills and dales. Already at my first destination, as I was wrestling with a gate, I became mesmerised by the twirping, tweeting and chirping of the morning chorus on a warm, sunny day. There must have been a dozen of species in my vicinity at any one time, though that wasn’t surprising seeing as I had arrived at what seemed like a haven – imagine mature, greening trees overlooking slopes of brightly yellow rapeseed, whose sweet scent filled the warm air, and meadows buzzing with bees and flies. You can hear the trinkling of a small stream by your side, lined with daffodils and snake’s-head fritillary, delicately pink cherry blossom trees and a pond. A sanctuary for wildlife.
In Kent, I arrived at some of the largest vineyards of my project, and was taken aback by the huge expanses of land covered by uniformly planted vines, stretching down the slopes and up again, as far as the eye could see. At one such vineyard where I spent many hours conducting surveys, mixed charms of 50+ finches kept me company. Finches frequently travel in mixed-species groups, and they can be easily identified in the air as they fly in quick bouts of flapping followed by gliding with their wings closed. They almost give the impression of being joyful, as they can often be heard chirping, as they pass just above your head. Over my time across UK vineyards, I’ve watched charms of goldfinches, linnets, and greenfinches with a few passing lesser redpolls, which are winter migrants to most of the Southern UK. These were delightful to watch, as they bounced between trellis wires and the ground, before suddenly taking to the air and crossing the vineyard, then falling back down to the ground. I’ve spent many hours squinting through my binoculars, trying to follow these fast-moving flocks and get a glimpse of what these little birds are doing. As finches are mostly seedeaters, I’ve noticed many feeding on the ground vegetation, including on common groundsel and dandelions, as well as using the wire trellis to clean their bills!
Sussex had some surprises and breath-taking views in store for me. I’d like to imagine that one of the vineyards could be seen from space, thanks to the hundreds and hundreds of brightly coloured, and roundly shaped dandelions carpeting the vineyard from edge to edge. The view was spectacular, and it made me sad to think that dandelions are often undesired weeds across many pristine lawns. This couldn’t be further from the truth here as the vineyard was full of finches and pheasants, feeding in between the vine rows on the dandelion seeds and flowers. A much more skittish animal was also enjoying a feast – the hare. These majestic mammals stood tall in the vines, or crouched low in soil grooves trying to hide from me – and successfully so until I unknowingly got too close, when the hare would burst into its 45mph sprint, leaving startled-me behind. As my journey through Sussex continued, and I left the beautiful dandelion vineyard behind, the hares didn’t leave me. Hares prefer mosaic habitats of grassland, arable fields, and woodland, so perhaps it’s no wonder that they were so numerous across vineyards, which provide plenty of hiding places in the ground depressions alongside vines. I do wonder how many leverets I walked by. I hope the answer is many as this beautiful species is on the decline.
There are too many memories from my journey to recall in one blog and as Sussex is a stronghold for vineyards, I could keep you sitting here for a while, so I’ll limit myself to a couple more stories; the first features members of my favourite group of birds – waders! When visiting vineyards, I didn’t expect to see waders, though in Brazil vineyards where I recently worked, Southern lapwing were plentiful! Anyhow, Eurasian lapwing in between vines didn’t fit into my schema, until I heard the unmistakable ‘peewit’ of a lapwing and saw the dramatic display of a male up in the air overseeing the vines. I can’t not smile when I see this species. Lapwing breed across arable fields and grasslands, and the vineyard where I saw this pair was relatively new, with a lot of the ground still exposed, and uneven with lots of flint scattered about, providing suitable breeding conditions. One of the common reasons for nest failure in lapwing, as well as in other waders, is (unintentional) destruction of nests by farm machinery; this vineyard pair didn’t seemed to have a nest yet, and we shall see if they are still occupying the vineyard when I next visit.
The lapwing vineyard was full of life, perhaps thanks to the rich surrounding landscape neighbouring it. During my visit, I didn’t feel alone for a second, as I was surrounded by the beautiful singing of skylarks, meadow pipits flushing from under my feet and the call of passing curlews, which pulled at my heartstrings. Whilst the skylarks and meadow pipits seemed to have made themselves at home within the vines, the curlews flew over the vineyard, before landing in a neighbouring arable field, where they likely went to feed.
I cannot move on before bringing you another story – an experience that will stay with me for years. It was the golden hour, the vineyard and surrounding woodland were lit in the warm and soft glow of sunshine, and I was just fitting the final few traps within the vines. I sensed movement behind me, so I turned around to see 3 bramblings, perching on a trellis wire and preening their feathers. They are beautiful finches, and I was lucky to see these three as they are sure to be soon heading to Russia and Scandinavia, where they breed. I paused to admire them in the low sunshine, which brought out the orange on their chests. This sighting was wonderful and as I marvelled at how lucky I was to be witnessing this, a red kite dived down at the 3 resting birds, hoping to catch an easy supper. Within a second, just as if someone burst a bubble in the air, all birds disappeared. The red kite left empty-clawed, and the three bramblings flew off into the woodland. It’s not often that you witness the attack of a bird of prey so close by; all of this happened within 2 meters of me, as I was likely hidden by the sloping ground.
The South West
I arrived in the South West after two weeks on the road, which seemed to have taken a toll on my car, but after a smooth visit to a nearby auto-store (with a coffee machine), both my car and I were energised and ready to explore. A couple of my best bird sightings come from the South West, so let’s dive in.
Many of the project vineyards are found deep within the UK countryside, away from big roads and cities, and some are naturally more remote than others. A long, narrow country track (almost an off-road experience for a hatchback) led to one such vineyard, and it was along this track that I saw a flock of about 20 wheatears. I think of wheatears as very elegant, thanks to their straight-cut facial markings, particularly seen in males. Though these birds have a green conservation status in the UK, they can only be seen on passage in Norfolk where I live, so it was real treat for me to be able to watch them on the country lane. This was a promising start to the day, I thought, as I arrived at the vineyard to start my morning surveys, where I was thrilled by the sight of corn buntings perching on trellis wire neighbouring arable fields, as well as a pair of common whitethroat, and a flock of fledgling house sparrows. Spring seemed more advanced in the South West, as the trees were fully green, the hawthorn seemed to have lost most of its blossom, and the vine buds were opening.
The end of my trip was fast approaching as I visited my final two vineyards, feeling unaware of where the time had gone and how it could have passed so quickly! It was a Sunday morning when I was chatting to a vineyard manager, and as much as I was engaged in the conversation, I couldn’t help myself looking past my companion and into the sky where 6 buzzards were majestically circling above the vineyard, as a lonely crow struck one of the buzzards, in an attempt to deter the group away from its nest. The signs of breeding birds in the trees, woodlands, and hedges neighbouring the vineyards were plentiful, from blue tits coming in and out of nest boxes and song thrushes gathering worms and little bugs from the ground to take back to their chicks, to dunnocks collecting moss for their nests.
After over two weeks of being immersed into the birdlife within UK vineyards, I felt that I’d seen a lot, but a pair of Canada geese waddling in between vines, and trying to navigate the trellis as they took off, took me by surprise on my final day of fieldwork. It seems that UK vineyards harbour a wide diversity of birds, some sticking to the bordering habitats, whilst others venture deeper in, smoothly flying (or hopping) in between the wires and vines, clearly thriving as they do so. I cannot wait to be back to collect more data and shed some light onto what affects the diversity of birds (and other species) across the expanding UK vineyards.
Update February 2021 – Vineyards for Bird Conservation
Globally, vineyards are expanding, and their management is intensifying, which poses concerns for their impact on biodiversity. What the past five decades have taught us is that agricultural expansion and intensification are bad news for biodiversity, by being the lead cause of habitat loss, contributing to species population declines and increasing extinctions worldwide (see Living Planet Report 2020). The question remains whether the impact of all crop production systems is equal and where vineyards stand in this.
Vineyards are widespread around the world, particularly across Mediterranean and tropical regions, which are climatically suitable for grape production. In these regions, vineyards have been a crucial part of the cultural and historical landscapes, being passed down through generations. Often in these cases, vineyards are managed with low chemical inputs, help to increase the heterogeneity (diversity and quality) of landscapes and contribute to supporting species-rich habitats. In other areas, vineyards are a recent addition, or undergoing rapid expansion, which threatens local habitats with loss and degradation. This poses questions over the ecological impact of vineyards, as many are increasingly more intensively managed. In many cases, these vineyards are important for the regional economy and livelihoods, making it even more important to understand how vineyards can be managed to support biodiversity conservation and to allow businesses to prosper.
In light of these changes, a team of scientists led by Anna Paiola, have been working to understand the impacts of viticulture on biodiversity and its interaction with management and the landscape. The researchers considered 218 research papers published since 1995 to understand how vineyards affect biodiversity conservation and summarised their findings in a paper published in 2020. Below I outline some key results from their work:
- How does increasing vineyard cover affect biodiversity?
The majority of studies found that increasing cover of vineyards in the landscape led to reduced biodiversity. This is likely due to decreased availability of suitable habitats for species, reduced quality of habitats or reduced connectivity between habitat patches. A reduction in habitat availability can occur when habitats such as woodlands are turned to vineyards, whilst habitat quality can be reduced when they shrink in size, or become polluted by vineyard management practices such as machine use (noise pollution) and chemical inputs. A reduction in connectivity can also occur when distances between remaining habitat patches increase, as parts of habitats are removed to allow space for vineyards. This was nicely illustrated by a study summarised by Paiola, which found that mammalian predators were more abundant in landscapes characterised by isolated and small vineyards with well-connected patches of natural habitats, which allowed continuity of movement.
In a small number of examples, increasing cover of vineyards helped to increase diversity, though this increase was limited to species thriving in open-habitats, such as grasslands, and farmland-specialists. For these species, vineyards can be a haven, especially if enriched with water bodies that attract invertebrates.
The structure of vineyards may be key to its effects on bird diversity. Vineyards were found to support less bird diversity than some other perennial crops, such as almond orchards and eucalyptus wood-plots, which was linked to the wire trellis system which makes vineyards very simple landscapes in comparison to woody crops. On the same lines, one study found that the trellis system affects vineyards’ suitability for birds. In this study, two trellis systems (see image below) were compared across Italian vineyards, and it was found that the traditional pergola trellis system supported more bird diversity, which the researchers put down to pergola vineyards being more complex and tree-like.
To help minimise the loss of diversity, vineyards can introduce certain landscape features that have a positive influence on bird species, and other species groups (see image above). For example, riparian corridors (“corridors” of natural habitat left untouched alongside rivers and streams) are fundamental for maintaining connectivity and aiding species’ movements. On similar lines, hedgerows and isolated trees can increase connectivity for birds, act as shelter and provide nest sites. All such features increase heterogeneity of vineyards and help to buffer against the negative effects of habitat loss that occurs during agricultural expansion.
- Is organic management better than conventional?
Perhaps surprisingly, the expected positive effect of organic farming on biodiversity was weak and inconsistent across different species groups. At the local scale (considering diversity at, or immediately around, vineyards), studies on birds and mammals are rare and yielded inconsistent results.
The positive effect of organic viticulture can be overshadowed by the impacts that conventional management has on biodiversity. Indeed, the authors found that organic and biodynamic viticulture weakly enhanced bird diversity at the landscape scale, though this effect disappeared in landscapes dominated by extensively managed vineyards. In landscapes that are a mixture of organic and non-organic vineyards, any positive effects of organic management can be cancelled out by the conventional activities, resulting in weak, mixed or zero net effects on biodiversity.
Similarities between organic and conventional vineyard management exist and impact biodiversity similarly. For example, both management styles use machinery, which has strong negative impact on bird diversity in vineyards. When it comes to other activities, such as chemical use, the difference in pesticide, fertiliser or fungicide use between organic and non-organic vineyards can be small, as some non-organic vineyards are low-input and manage their vineyards in-line with organic regimes.
Overall, the current research suggests not-so-optimistic effects of organic viticulture on biodiversity and disentangling the differing impacts of the two management styles on biodiversity requires further study. Nonetheless, it’s likely that the provision and maintenance of biodiversity-friendly natural habitat patches are crucial for enhancing the positive effects of organic viticulture on biodiversity.
- Cover crops support biodiversity and are an important management practice in vineyards
Over the recent years, the growing awareness of soil degradation and erosion has led many vineyards to try growing cover crops, with the benefits of this practice stretching to birds. Studies have found that ground-vegetated vineyards hosted more biodiversity than vineyards without ground cover. For birds, the effect of ground cover varied between different species, which can be largely explained by the differences in foraging habits. Granivorous birds (seed-eating) which forage on bare soil were unlikely to benefit from cover crops, but other species which eat insects from the ground, such as hoopoe, woodlark or common redstart, benefitted from the increased ground cover. These species prefer “kitchen-dining room” systems, where 40-60% of ground is left as bare soil and the rest is vegetated. This is because arthropods, which these birds feed on, are mostly abundant in taller grasses where visibility for birds is low so they rely on the bare soil patches to find and catch their prey. Additionally, some ground-breeding species, such as woodlark, require patches of dense vegetation cover for nesting, and likely benefit from cover crops. These results suggest that a mixed approach to ground-vegetation management that aims to increase the heterogeneity of sward heights is likely to have the highest positive impact on bird diversity.
The general patterns of the effects of vineyards on biodiversity mirror those observed in other crop systems, particularly when it comes to the importance of heterogeneity within vineyard-landscapes, and the mixed effects of organic management. This research review shed some light on the number of practices that vineyard managers can implement to support bird diversity on their land, and which practices to avoid, such as chemical weeding and tillage that have consistent negative effects for biodiversity across many crop systems.
Whilst providing answers to some questions, the review also found some missing pieces in the great agroecological puzzle of sustainable viticulture. A key missing piece is equal representation of world’s vineyard systems, as the majority of studies were carried out in North America and Europe, excluding the UK, which remains unstudied. Addressing this gap within the UK is a key aim of this research collaboration with the SWGB.
Linked paper: Paiola, A. et al. 2020. Exploring the potential of vineyards for biodiversity conservation and delivery of biodiversity-mediated ecosystem services: A global-scale systematic review. Science of the Total Environment, 706: https://doi.org/10.1016/j.scitotenv.2019.135839
Update January 2021 – Bird Boxes in Vineyards
Birds are a welcome sight by many farmers and land managers. Their morning choruses signal the arrival of spring, and a charm of finches, a murmuration of starlings or a volery of long tailed tits bouncing in the air is sure to brighten any countryside walk in winter. With the increasing awareness of the poor state of UK birds, the provision of breeding boxes is a common conservation practice used to support bird populations. This blog will review the effects that this practice can have for birds and soft-fruit production.
Bird boxes come in many shapes and sizes, and these differ depending on the bird species they are meant to attract. The species that occupies the box will affect how the local bird community is affected and how this translates to ecosystem functions within the farm that can affect crop yield and quality.
With increasing numbers of nest boxes emerging across our farmlands, this conservation practice has also been receiving growing scientific attention. Scientists have primarily explored these two questions:
1. Are bird boxes good for bird diversity?
2. How can provision of nest boxes affect crop production?
In this post, I’m going to summarise the answers to these questions so without any further ado, let’s dive into some science.
Are bird boxes good for bird diversity?
If I ask someone why they provide nest boxes for birds, the most common answer I’ll get is to encourage birds, of course! But does this practice actually work?
Nest boxes can be built to encourage passerines (or “garden” or “small” birds), or larger birds including owls and raptors. The effectiveness of providing boxes to increase on-farm bird populations has been tested with overall positive results.
Let’s start over in Californian vineyards where one research group led by Julie Jedlicka built 46-48 nest boxes for a small insectivorous (insect-eating) species, the Western bluebird. Here, the nest boxes led to changes in the vineyard bird community. The abundance of insectivorous birds in vineyards with nest boxes was 2.6 times higher, which was driven by the increased presence of fledgling bluebirds. However, the overall bird diversity remained unaffected.
Provision of nest boxes in vineyards may not alter the bird species composition at the landscape scale. A team of researchers also led by Jedlicka surveyed bird communities in vineyards with and without nest boxes, and within woodlands surrounding them. The species richness of birds within vineyards was primarily driven by woodland presence and not the boxes. This suggests that retaining natural vegetation cover around vineyards is key for supporting diverse communities of birds, but provision of nest boxes can effectively support bird species already using vineyards.
Though other studies have not monitored the changes in bird diversity that might have been brought about by nest box installation, it’s interesting to note that bird species common to UK vineyards such as great and blue tits, house sparrows, kestrels and barn owls became common residents.
How can provision of nest boxes affect crop production?
The simple answer is – (mostly) positively! Whatever bird species you’re attracting with nest boxes, they are likely to affect ecosystem functions within your vineyard. Aside from breeding in the nest boxes, the birds are likely to feed within the crop and consume whatever’s around. Insectivorous birds may turn to insect pests, whilst birds of prey to the fruit-eating bird species.
With the growing interest in measuring ecosystem services, these dynamics have been reasonably-well studied. Vineyards and fruit orchards with nest boxes were found to experience less herbivory and higher consumption rates of insect pests by birds. In some systems, this effect was impressively strong – for example, caterpillar damage in apple orchards with nest boxes was reduced by 50%!
Many insectivorous species are generalist predators and may be consuming natural enemies of pests. This was found to be the case in the Californian vineyards where breeding birds consumed pests and their natural enemies. This risked an increase in pest abundance resulting from reduced pest control by the natural enemies, but luckily, the overall abundance of pests in vineyards with nest boxes was lower. This does, however, highlight a risk that is worth bearing in mind!
When your problem is with fruit-eating birds, nest boxes might also be the answer. In cherry orchards and vineyards in America, the provision of nest boxes for kestrels led to a reduction in the abundance of fruit-eating species. In fact, this effect was so strong in one orchard that the scientists estimated that for every nest box built, $84-$357 of cherries were saved!
I’m making nest boxes seem rather amazing, right? Before we all get too excited, it’s important to highlight some caveats. The provision of ecosystem services is variable between farms. For example, the provision of nest boxes in organic apple orchards did not result in a reduction in caterpillar damage. Even in cases when birds successfully control pests, this service may be localised to areas immediately by nest boxes as breeding birds don’t like to stray too far. Another issue is with attracting birds to breed in the boxes in the first place, which seems to improve with time from box installation, but nest occupancy can remain low and variable. For example, the average nest occupancy by raptors was found to be 30% across years, but this was highly variable between years and sites, as some sites in some years failed to attract breeding raptors.
Take home message
Nest boxes are a great conservation practice that can support local bird communities, but much remains much to be discovered. There’s no doubt that with careful management, nest boxes could be used to benefit bird diversity and crop production but it’s important to remember that vineyards are complex systems and the effectiveness of nest boxes at attracting desired bird species is likely to be impacted by vineyard management and the surrounding landscape.
What are your experiences with nest boxes? I’d love to hear your stories, and as always, if you have any questions or would like to discuss the nest boxes at your vineyard, don’t hesitate to get in touch!
Birds in UK vineyards – an introduction
PhD candidate, Natalia, from the University of East Anglia is teaming up with Sustainable Wines of Great Britain (SWGB) to study birds in UK vineyards. Global biodiversity needs protecting more than ever before, and there’s a lot of pressure for agriculture to become sustainable. The key to achieving sustainability is to farm with nature in mind, and understanding the interactions between winegrowing and diversity is necessary for informing sustainable practice. This article is the introduction to the new blog series, which will follow Natalia’s research adventures in UK vineyards and bring the latest research about birds in fruit farms to you.
The unprecedented times
If you’ve watched the Prime Minister speak at all in 2020, you’ll be well aware that we are living in unprecedented times. But I urge you to look beyond the pandemic. You now know how to do your bit at keeping yourself and others safe, patting your coat pocket in panic whenever you leave your house to check your facemask is still there. I wonder however whether you know how to protect the biodiversity on your vineyard? You’ve probably heard a news piece about the vaccine trials or the new tier system within the past hour, but when was the last time you heard anything about addressing the biodiversity crisis or sustainable agriculture?
“Biodiversity as we know it today is fundamental to human life on Earth, and the evidence is unequivocal – it is being destroyed by us at a rate unprecedented in history.”
That quote, from the Living Planet Report 2020, will stick with me for life. Globally, species populations have declined by 68% since 1970. In Europe, this decline over the past five decades has been lower, but this is largely because biodiversity here has already suffered substantial declines pre-1970 due to land use change, habitat degradation and unsustainable use of pesticides and fertilisers that polluted our soils and waterways.
The loss of biodiversity means more than the loss of the morning chorus. It means the loss of nature’s functions. The loss of ecosystem services. The loss of money. Our livelihoods, both as producers and consumers, are embedded within nature and we need to recognise this in order to protect biodiversity and economic prosperity. Nature is crucial for the functioning of agriculture through biological pest control, pollination or water retention, just to name a few.
Though this is not making the daily headlines, the UK government recognises the necessity to change how we produce food. The 25 Year Environment Plan calls agriculture to put the environment first. The government has promised us a Green Brexit, making use of the “once-in-a-lifetime” opportunity to reform how we farm and care for our land. This is going to be reflected in the new Agricultural Bill, which promises to reward land managers for the delivery of “public goods”, which will encompass ecosystem services.
How do I manage my vineyard in a way that nurtures biodiversity and delivers those promised nature’s functions, I hear you ask? Many of you as winegrowers, and us as scientists, don’t know all the answers to this question – yet. A new research collaboration between researchers from the Universities of East Anglia (UEA) and Cambridge and the SWGB scheme is going to address these questions when it comes to birds and wine.
A silly question, I know. We all love wine. And actually, that is partly the reason why this research is important. The UK winegrowing industry has been growing and the quality of British wines has been increasingly recognised. The number of British wines being awarded increased from fewer than 5 in early 2000 to 50-75 (!) in recent years. As the UK wine industry grows, so does its impact on biodiversity, making it even more important that the effect is positive. Despite this, no research has studied birds in UK vineyards.
The second reason is climate change, which counterintuitively might benefit the British wine industry. Grapes are a climate-sensitive crop, and an international team of researchers has recently shown that many current wine growing regions will no longer be climatically suitable under 2-degree C warming. However, UK, and much of Northern Europe, will become more favourable regions for growing a wide variety of wine grapes. This is likely to mean a further growth of the British wine industry.
Perhaps yet another silly question, but why should one be interested in studying birds and not bees or mammals? There are two answers to this question. The first one is that it’s simpler and logistically easier to study a single group of animals than multiple groups at the same time, and birds is where my expertise lies. Secondly, birds are an interesting group to study as they can take on a wide range of behaviours within an agricultural system.
Within crop-systems, birds can be both friends and enemies. The below graphic, produced by an American team of researchers lead by Karina Garcia, neatly summarises the main ways in which birds can affect crop yield and quality. The graphic includes behaviours of birds that help production and those that reduce yield. In ecological terms, the positive behaviours are termed “ecosystem services” and the negative behaviours “ecosystem disservices”.
I encourage you to have a look at the graphic and though I know it looks complicated, it’s really worth understanding how dynamic bird communities within fruit farms can be. How many of these behaviours have you seen in your vineyard?
But we’re looking at strawberries, I hear you say! Yes, and that’s part of the issue that this new research collaboration is trying to tackle. The roles of birds within UK or European vineyards have rarely been studied*. Studies from key winegrowing regions (Australia, US) have shown similar behaviours of birds to those observed in strawberries, so we can assume that many of these behaviours also apply to UK vineyards and are worth investigating.
* the few studies that have studied birds in European vineyards will be discussed in future blogs.
Birds’ behaviours within farms are complex and it is crucial that we understand them so that we can “farm with nature in mind”. We ultimately want to protect biodiversity, whilst producing high yields of high-quality crops. Managing birds may be necessary in order to balance their net effect on production by enhancing the positive behaviours and decreasing their negative impacts. And that’s exactly what this study is aiming to inform by:
- understanding how bird diversity varies across UK vineyards,
- quantifying birds’ net impact on wine grape production,
- testing approaches to managing birds within vineyards.
The results of this study will contribute to SWGB’s guidelines for managing bird diversity in vineyards.
Spreading knowledge is another aim of this research collaboration and through these blog posts, Natalia will be bringing exciting research about birds in fruit farms to you. If there are any questions or topics you’d like to see being explored, please let Natalia know!
About the author
My name’s Natalia Zielonka, and I’m a PhD candidate at the University of East Anglia. I’m supported by the UKRI BBSRC Norwich Research Park Biosciences Doctoral Training Partnership, and my great supervisors are Dr Lynn Dicks (based at the University of Cambridge) and Dr Simon Butler (UEA). If you have any questions then please don’t hesitate to contact me on email@example.com and via Twitter: @Nat_B_Zielonka.