The UK Butterfly Monitoring Scheme has recently released its report for the 2023 season and it was a mixed bag. The results provide a picture based on recording at more than 3000 sites nationwide. Some species had very good years while others had a particularly bad year. In some cases, it was easy to put the poor showing down to the impact of the summer drought of ’22. Those butterflies associated with damp conditions, such as the Green Veined White and the Ringlet, did particularly badly last summer. Their larvae probably found it difficult to find sufficient plant material on which to feed in the parched landscape. Particularly disappointing is the continued decline of the Small Tortoiseshell, a lovely looking insect, familiar to most but becoming increasingly uncommon. As it is faring better in the moister north and west of the country, this decline could be a result of climate change. That impact may be expressed on the insect itself or it may be that the parasites that attack it are favoured by the changing climate.
One species which did well in ’23 was the Holly Blue. On my transect outside Tisbury, I recorded more than twice as many in ’23 than in any of the previous 8 years. I only saw one there in ’22. It is another butterfly that is regularly affected by parasites, and this leads to a boom-and-bust cycle every 4-6 years. The caterpillars may be attacked by two species of parasitic wasp, which lay their eggs into the larva’s body where they hatch and feed. When the wasps are rare, the population of Holly Blues is able to increase but soon, with increased numbers of caterpillars to prey on, the population of the parasitic wasps grows. Eventually, the parasitic wasps become so abundant that they cause the population of the host butterfly to plummet. That then causes the wasp populations to crash for lack of larvae and the cycle begins again. Now is the time to look out for Holly Blues in sheltered sunny gardens, hedgerows and woodland glades. They will often be seen flying amongst the tops of bushes and hedgerows, often where there is holly or ivy present. Although by no means a certain guide, if you see a small blue butterfly skipping around at height, amongst bushes and trees, it will be a Holly Blue; other blues are more likely to be seen close to the ground. In spring, eggs are often laid on holly flower buds. These give rise to a second brood flying later in the summer and, by contrast, the females of this brood generally lay their eggs on the flower buds of ivy. A Holly Blue flitting around the garden is a sure sign of spring and it will be interesting to see if the numbers of last year are exceeded or whether this season brings a crash. Andrew Graham I love to hear skylarks singing on sunny days above the downs and the fields around Tisbury. It must be one of our most well-known birds, as there must be few who do not recognise its song, delivered from high in the sky. An inspiration to artists, poets and composers, the skylark is often easier to hear than see, and when on the ground, its drab inconspicuous plumage can make it difficult to spot. It may only be up close that you can spot its distinctive crest, which clearly separates it from the somewhat similar, but less stocky, meadow pipit, which has a far less exuberant song.
Although there is a good handful of lark species to be found on the continent, there is just one other that you might see in the UK, the rarer woodlark. This is a bird of the heaths, so the best place to look for them near here would be in the New Forest. Slightly smaller than the skylark, with a short tail that makes it look a bit like a bat when in flight, the woodlark shares the same brown streaky plumage as the skylark. The plumage of larks and pipits provides effective camouflage for the birds when feeding and nesting on the ground. This is a common adaptation for ground nesting birds and serves well to protect them from conventional predators. Unfortunately, it does little to protect them from challenges brought by the loss of stubbles, and other changes to agricultural practices. Numbers have dropped by 15% over the last 30 years and the bird is now Red Listed in the UK. Ground nesting birds are particularly vulnerable to straying dogs. This is one of the reasons why the Countryside Code makes it a legal requirement to have your dog on a lead on open access land between 1 March and 31 July, and under effective control for the rest of the year. Responsible pet owners will help our endangered birds to have a successful breeding season. Andrew Graham As the weather warms and the days lengthen so we begin to see more wildflowers in the country and along the roadside. After the spring equinox is referred to as the vernal period. Late winter before the equinox is referred to as prevernal. Classic prevernal flowers are those that bloom before trees and bushes come into leaf and throw shade over the plants. An example is the primrose which we will find blooming in woodlands and under hedges before the leaves break.
The primrose spreads its leaves in a rosette against the ground around the flowers. This allows it to maximise the light that they can absorb while the sun remains relatively low. This gives them a competitive head start, allows the flowers to be fertilised and set seed early in the year before other taller plants shade it out. At this time, its bright yellow flowers are hard to miss and are a welcome source of nectar for any early emerging insects. Later in the year the leaves become pallid and die back. Another flower providing nectar at this time of year is Coltsfoot. This plant looks like a small dandelion but in contrast to the primrose, it flowers before its leaves appear. Each composite flower is held on a short scaly stem; quite different to the dandelion’s smooth one and similar to sedum flower stems. As the flower’s centre is dense, it also looks like a large all-yellow daisy. It is a creeping perennial weed of rough ground and field edges and as it spreads by rhizomes underground if it gets into your garden, it can become a pest. The leaves emerge after the flowers have died back and are shaped like a heart or horse’s hoof, hence the name. Historically it was used as a remedy for coughs and colds. Andrew Graham Ravens are beginning to breed this month; usually laying eggs in late February.
By the beginning of the 20th Century, persecution had reduced the distribution of ravens to the coastal and upland districts of the west and north of the UK. Where I grew up in Weymouth, ravens were a rarity only occasionally seen on the Purbeck coast. Similarly, when I lived in Essex and Berkshire before moving to Tisbury, I just never saw them. So, their obvious presence was one of the things I first noticed on our arrival here. The raven's range has increased again, spreading south and east, with Tisbury well within the area recolonised during the last 50 years. Nationally, there has been an estimated population increase of 40% in the last 25 years. As that growth has taken place, so nesting has expanded beyond the cliffs and crags previously favoured, to tall trees. For nesting sites, they seem to prefer wooded areas with large expanses of open land nearby, which sounds like a fair description of our local landscape. They currently avoid urban areas, although in earlier centuries when they were more common, they frequented cities, alongside other birds such as kites. The raven is distinguished from its cousins, the crows, by its greater size – comparable to a buzzard – and by its larger, heavier, black beak and shaggy feathers around the throat. Its entirely black plumage has a purple iridescent sheen when seen close up. It also has a longer, wedge-shaped tail which shows up well in flight. This involves less wing flapping and more soaring and acrobatics than crows. Indeed, they seem to enjoy goofing around in the sky, often in pairs, flipping over to fly upside down, closing wings to drop steeply and engaging in mock battles with their mate. Their call may grab your attention before you see them: a deep croak of “cronk cronk” or “pruck pruck” may alert you to a pair circling high above the village or in woodland treetops. They are long-lived birds and live for 10 -15 years or more in the wild although some at the Tower of London have lived beyond 40. They mate for life, usually nesting in the same location once paired. Ravens feed mainly on carrion but are omnivorous and opportunistic. When available, they’ll eat grains, acorns, berries and fruit as well as invertebrates, amphibians, reptiles, small mammals and birds. The raven’s brain is among the largest of any bird species. They are intelligent and show problem solving skills. This may have contributed to its ability to find food which has helped the speed of its recolonisation. Supposedly, the kingdom will not fall to a foreign invader as long as there are ravens (presently captive) at the Tower of London. It is not clear where this idea comes from, although it may be another romantic invention of the Victorian era. It does, though, offer people a chance to get up close to these magnificent birds. Andrew Graham Towards the end of November, walking the footpath northwest towards Weaveland Farm, I noticed a bright red poppy in bloom in the stubbles of the adjacent field. Scanning the area, I realised that there were hundreds of them blooming throughout the field.
Climate change is affecting the number of plants that we can expect to see in the winter months. In some cases, a mild autumn will allow plants to flower later into the early winter than is normal; in others, a lack of frost or extended cold spells can encourage spring species to flower early. In 2012, the Botanical Society of Britain & Ireland (BSBI) started promoting an annual hunt for plants in flower during a four-day period over New Year – the New Year Plant Hunt. This has become increasingly popular and, in recent years, over 2500 participants recorded lists of flowering plants from over 1,700 locations across Britain and Ireland. Initially, it was set up as a bit of fun for botanists at a quiet time of the year. Now, a decade on, it is helping to build up a picture of how our flora is responding to changing weather patterns. Between 30th December and 2nd January, participants are asked to count all native and non-native plants in flower seen on a walk of no more than three hours, excluding species obviously planted in gardens. Many of the species most frequently seen are common, well-known ones, such as Daisy, Dandelion, Dead Nettle, Groundsel and Gorse. The BSBI provides Spotter Sheets with pictures of the Top 10 and Top 20 most frequently seen flowers to help identification. You could also take photos and then try to identify the flowers when you get home. Hunters are then asked to enter records of their sightings on the BSBI website where they can also see other records coming in (www.bsbi.org/new-year-plant-hunt). This month, we are collating the results of the plant hunt by our members into a group response and are offering a prize for the best pictures taken from those under 10 and between 10 and 21 years of age. Keep an eye on our online media for an update on this! Naturally, sheltered locations in the south tend to yield more species than exposed ones in the north, but amazingly some hunters have found more than 70 species. Urban areas can provide a “heat island” effect, so it might be easier to find flowers in the walls and alongside paths in the village. Taking part in the hunt is a good excuse to get out for a walk after the festivities, and the results will contribute to the wider nationwide study; it will also be interesting to see the effects of the recent weather. Andrew Graham Many of us will soon be putting up our Christmas trees for the festive season. Decorated trees are a tradition imported from Germany by the royal family in the 19th Century. For me, the traditional species is Norway Spruce, but that has gradually been replaced by the Nordman Fir, which loses its needles less quickly. They are generally around 10 years old when cut and, with 6-8 million trees sold in Britain each year, most of which are grown here, their plantations cover a considerable land area.
Conifer plantations have had a bad press. There was a drive to create a national reserve of timber, after woodland cover reached an all-time low after the First World War. This resulted in large-scale afforestation of areas where soils were poor, often in ugly rectilinear blocks of single species. While young plantations had a short-lived boost in biodiversity, as the canopy closed, these woodlands often became lifeless. As conifers produce an economic yield up to 6 times faster than deciduous trees, and as the softwood they produce is in high demand for a huge number of uses, we do need these trees. However, management is very different today, large monocultural blocks are a thing of the past. More diverse mixes of species, planting which takes more account of drainage and landform, and the retention or creation of open habitat areas within the forest have become the norm. A number of conifer stands in an existing deciduous wood may increase diversity, while improving commercial viability. Many ancient woods have survived on this basis which might otherwise have been lost as woodland habitat. More forests are now being managed on a continuous cover approach. This seeks to avoid extensive clear felling – taking out all the trees in an area at once – but to create more structurally diverse forests with a greater range of species under a continuous canopy. This avoids sudden changes in habitat conditions, to which wildlife finds it difficult to adapt, reduces erosion and could make the forest more resilient to risks from disease and changes in climate. Obviously, this approach cannot be applied to the Christmas Tree plantations. However, as the trees are spaced to let the light get in, to create the conical trees we love, they can still provide a home for wildlife, especially if pesticides are avoided. It is estimated that artificial trees generate 7 - 20x more carbon than a natural tree. So, if you do have one, it is essential to reuse it as many times as possible. But those of us sticking with natural trees can reduce the carbon footprint by sourcing it locally to keep down the tree miles and by disposing of it thoughtfully. A tree bought from a superstore may have been brought all the way from Scotland (and might have been felled weeks ago and so be ready to drop its needles as soon as you decorate it). The worst option for disposal is to send it to landfill; chipping, burning, or composting all result in lower carbon emissions. Wiltshire County Council will collect old trees from residents with green bins and compost them, or there are charities which collect them for recycling in return for a small donation. Andrew Graham The British Trust for Ornithology (BTO) is an environmental charity which aims to increase our knowledge of birds and other wildlife and, using data gathered by volunteers, seeks to inform decisions on government policy, land use and conservation priorities.
To do this, it organises a range of recording schemes through which volunteers gather data about birds’ numbers, distribution, habits, breeding success, and more. One of these schemes is the Wetland Birds Survey (WeBS) which counts the UK’s internationally important non-breeding waterbirds. This includes wildfowl (ducks, geese, and swans) waders, grebes, cormorants, and herons. Since it started in 1947 this scheme has grown and now over 3000 volunteers monitor 2,800 sites. Each volunteer adopts a location to count once a month, with the core counting season between September and March as this is when the numbers of many species peak. The largest aggregations of waterbirds are at our estuaries. But inland lakes and wetland areas are favoured by certain species so cumulatively they also contribute. Locally, Fonthill Lake and Wardour Castle Lake are monitored, but as waterbirds can be very mobile, and one can often see wildfowl flying between these two areas, there is a risk of double counting. So, one Sunday a month is designated as the core count day, so that all counters can visit their sites on the same days. Records over decades for these sites show significant changes in the balance of species seen and their annual peak counts. Unfortunately, most of these changes show a downward trend. Collecting all the information together from all sites across the country allows the BTO to generate indices and trends for each species. As many of the species that overwinter in the UK breed elsewhere, in Europe or the Arctic, changes in abundance relate to conditions across large parts of the world. Monitoring these bird numbers help us to assess how wildlife populations are responding to environmental change. The efforts of all those volunteers contribute to documents such as the recently published State of Nature report which provides a benchmark for the current status of our wildlife. It doesn’t make happy reading, but one can be assured that it is based on the best data available. Andrew Graham The end of summer always brings lots of wasps to interrupt our picnics or irritate us in pub gardens. Another member of the wasp family, the Asian Hornet has been in the news lately because of concern about its potential to colonise the UK. It was accidentally introduced into southern France, probably off a container ship, in 2004, since when it has spread rapidly across Europe and towards the Channel.
The Asian Hornet is a very effective predator of insects, including honeybees and other pollinators. It can cause significant losses to bee colonies, and potentially other native species. As one hornet can consume up to 300 bees a day the species could have a devastating impact on our bees if it becomes established. As a result, much effort has gone into publicising the threat and encouraging people to report any sightings. There is even an “Asian Hornet Watch” app to help you to do this. It provides useful photos of the Asian Hornet and other species with which it could be confused. This includes the continent’s only indigenous species, the European Hornet. You can use the app to report a sighting, ideally with a photo. The way to identify an Asian Hornet in three steps is to ask: 1) does is it look mostly black; 2) has it a wide orange stripe on 4th segment of the abdomen (body or “tail”); and 3) do its legs look as if they have been dipped in yellow paint? Taken together these factors clearly separate it from other candidates. Our European Hornet, which has is quite common in the south of England, is a handsome insect slightly larger than the Asian Hornet and about twice the size of a wasp. It has similar markings to the wasp but is chestnut brown and yellow rather than black and yellow. It is not nearly as aggressive as the wasp and will only sting humans if threatened. Indeed, males do not even have a sting. Like other wasps they make paper nests of chewed up wood or bark, often in hollow trees. We may see them foraging in good weather throughout the autumn before the newly mated queens go into hibernation ready to start a new nest in spring. The rest of the colony, including the old queen, dies by winter. You may see the queens stocking up on nectar from flowers prior to hibernation. Since 2016, nationally there have been 52 confirmed sightings of Asian Hornets and 45 nests destroyed. Most sightings have been in Kent and although there have been a few in Dorset and Hampshire, there have been no sightings in Wiltshire yet. It is certainly important to prevent the spread of the Asian Hornet, but we shouldn’t allow our concern to lead us to unnecessarily persecute our native, and largely harmless hornet species. Andrew Graham In the late 60s and early 70s, Dutch Elm Disease wiped out millions of trees throughout the country changing the landscape for ever. A promotional campaign at the time encouraged us to “plant a tree in ‘73” and then “plant one more in ‘74” to fill at least some of the gaps.
Today, there is much talk about tree planting to lock up carbon and combat climate change. But currently this seems to assume planting will be on a relatively large scale with the expectation on rural landowners to take the initiative. However, we can all play a part. Significant trees have a tremendous impact on how our villages look. Imagine the view up and down Tisbury High Street without the cedar at the bottom of the hill or the Christmas tree outside the Benett. Or what the Avenue would look like without the line of limes along it. But even the longest living trees will die eventually and if others have not been planted during their lifetime as replacements, their loss is a shock and leaves us all worse off. As well as old age, we lose trees, or parts of them for numerous reasons. Ash Die Back Disease means that we are likely to lose huge numbers of ash trees in the years ahead. Will they be replaced? Trees are lost to development, while others just get too big for their location. Felling is not always necessary though as a good tree surgeon can bring the tree back to an acceptable size and shape to flourish for many more years. Unfortunately, it is easy to have double standards on trees. We like to see them in the view but don’t want them to block our view. We like to see blossom, berries, and autumn leaf colour (ideally on someone else’s land or garden) but might not want seeds, dead flowers and leaves on our cars and gardens or noisy birds disturbing our sleep in spring. Planting a tree is a vote of confidence in the future. The people who planted the largest trees we see around us never lived to see them in their prime as we do. By the time trees planted today reach maturity our successors may find their shade particularly welcome in a warming world. So as autumn approaches, is there scope to plant more trees around the village? Plant a tree in ’23? Or can we find room in our gardens? Some species never grow to a great size and can be controlled but still have a contribution to make. If we already have trees around us, let’s look after them for everyone’s benefit now and in the future. Trimming, lopping, and felling without adequate replacement will inevitably leave future generations the poorer for their loss. Andrew Graham Midsummer is usually a time when I see fewer birds in my garden. Until recently, the sparrows had been evident as they busily created, and then fed, their brood and sparring blackbirds defended their territories. But things seem much quieter now. There may be plenty of food in the garden and countryside that they do not need to visit the bird feeder, or they may be keeping closer to cover because the adults are starting to moult.
There has been much debate about the benefits, or otherwise, of putting food out for birds in our gardens and whether we are interfering with their natural survival rates. In the UK, we collectively put out astonishing amounts of food for our birds. It allows us to see birds close-up, get a better look at their plumage and movement, which helps us to identify them more easily in the field. Of course, we all hope that in providing food we are helping them to thrive and at least maintain a stable population. Much research has been done and the consensus seems to be that garden feeding is supplementary, that is, the birds do not wholly depend upon it and can survive without it although extra food can improve over-winter survival in several species. There is no evidence that habitual use of feeders causes birds to lose the ability to forage in the wild. It is true that those species which use feeders have been more successful, while the populations of those that do not have been more stable, but our feeding is just one positive environmental change which is more an offset against the many other negative ones. So, while it appears we have no need to worry about whether to feed, what is important is the way we feed the birds. Gathering many species to feed together in a way that they would not do naturally, risks spreading disease and making them a target for predators. We need to offer the best quality food we can afford, ideally putting out no more than the birds can consume within the day. A mix of different foods will support a variety of species, while your garden’s plants can help by providing invertebrates, seeds, nuts, hips, and berries for them to feed on. Ideally, there should be some food available all the year round as shortages can occur at any time. We should move feeders around to avoid an accumulation of waste and droppings. We should also avoid shrubs from which cats can pounce and locating them near nest boxes as the birds in the box may think the feeder is “theirs” and waste time and energy trying to drive off other birds. The feeders themselves also need regular (e.g., weekly) cleaning with soapy water, to help stop the spread of disease. Lastly, water is as necessary to birds as, and sometimes less available than, food. A supply of water, refreshed daily, will be welcome for bathing as well as drinking. Andrew Graham |
Photo: Avocets (Izzy Fry)
The headers display photos taken by our members. Do get in touch via the Contact Form if you'd like to submit a photo for selection.
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