Butterfly survey – 2011 numbers 22% down

Small tortoiseshell slide continues

May 2012. Butterfly numbers in the UK countryside fell by almost a quarter last summer, according to a new scientific study.

22% fewer butterflies in 2011
The Wider Countryside Butterfly Survey (WCBS) revealed that butterflies suffered a disappointing 2011 compared to 2010 with recorders seeing 22% fewer butterflies on average. Last year's record-breaking cold summer and the ongoing deterioration of suitable butterfly habitat across the countryside are seen as causes for the fall in numbers.

Small tortoiseshell - Big decline
Garden favourite the Small tortoiseshell was one of the species badly affected, with less than one seen per kilometre walked on average in the countryside. Such low numbers are a cause for concern given that less than a decade ago the butterfly was likely to be seen in almost every garden and flowery place through the summer months.

The drop in Small tortoiseshell sightings from the WCBS mirrors an alarming and ongoing decline for this once ubiquitous species. This is the first time that a comprehensive survey has shown how few are now found across the countryside as a whole.

Wider Countryside Butterfly Survey
The WCBS involves counting butterflies in more than 700 randomly generated 1km-squares across the UK countryside. The scheme helps assess the health of butterfly populations across the wider countryside, rather than specially managed hotspots such as nature reserves.

In 2011, recorders saw on average 47 butterflies from seven species per-survey made over July and August. This represents a 22% reduction in numbers from 2010 and an alarming 41% reduction from 2009 when recorders saw an average of 80 butterflies and eight species. There were 43 visits where were recorders saw no butterflies at all - double the 2010 figure.

Common Blue & Wall declining
The Common Blue also struggled in 2011; the butterfly was present in only one-third of squares compared to over half in 2010. The Wall declined in distribution for the third consecutive year with this once common species now largely absent from central England.

Wall butterfly 

Meadow brown most numerous

The Meadow Brown was the most widespread and abundant species, being found in more than 80% of squares.

WCBS co-ordinator Dr Zoë Randle said: "The new survey is proving vital in getting better information on how our common butterflies are faring across the countryside as a whole. The gloomy results show we need to step up efforts to rebuild a better countryside for butterflies."

Kate Risely, Breeding Bird Survey Organiser at the BTO added: "It is important to carefully monitor the numbers of our wider countryside butterfly species in order to detect potential threats to their populations.

"Results from the upcoming 2012 survey and in years to come will show whether these declines are sustained. We're very pleased that bird surveyors can contribute to butterfly recording, highlighting the value of dedicated naturalists in our society."

The WCBS is run by Butterfly Conservation, the British Trust for Ornithology (BTO) and the NERC Centre for Ecology & Hydrology (CEH) as part of the United Kingdom Butterfly Monitoring scheme (UKBMS).

http://www.wildlifeextra.com/go/news/butterfly-survey-2011.html

Almost three quarters of UK butterfly species have decreased in population during the last decade

Common species declining & many species spreading northwards
December 2011. Butterfly Conservation and the Centre for Ecology and Hydrology (CEH) findings show 72% of species declined in abundance over ten years and distributions of 54% of butterflies fell, many sharply.

The results, from The State of the UK's Butterflies 2011 Report, provide further evidence that the European Union target to halt the loss of biodiversity by 2010 was not met. But the report also reveals that intensive conservation efforts have started to turn around the fortunes of some of our most endangered butterflies.

Large blue and Heath Fritillary
The previously extinct Large Blue showed increases in population and range and the Heath Fritillary has been brought back from the brink of extinction.


High Brown Fritillary and Duke of Burgundy
But ongoing declines have left the High Brown Fritillary and the Duke of Burgundy facing the very real threat of becoming extinct in the UK unless they benefit from further conservation work.

The report shows for the first time that the total number of common and widespread species fell by almost a quarter in 10 years, indicating underlying problems with the UK's environment.

Read more here ...

2011 is the year to bring insects in from the cold

The honeybee is in peril, but every gardener can help by planting pollinator friendly plants in their gardens and allotments during 2011.


Gardening, for me, has turned a completely new corner. I used to love it - like cooking - for the disengagement it allows, the absorbing, practical, satisfying, creative parts of gardening that make it the perfect thing to do when you want to cut off from the rest of life. I also love it for rooting me firmly in the time of year and weather. By Sarah Raven


But I'm seeing it differently now and I think that's probably to do with getting older - with having hung around in gardens for 20 years.

I don't want this to sound too inflated, because after all, it is only a garden, but I am beginning to think of my garden as a contribution to the world. It has - or can have - effects and influences beyond itself.

It is a small patch that I can turn into a dynamo for a richer and healthier landscape, and now is the ideal time to make definite shifts - a New Year's resolution, in fact.

Why insects matter

What's driving me is the decline in wild pollinators and managed honeybees.

For example, Britain's butterflies have never been so threatened, with 24 per cent lost since 1800 and 75 per cent of species in decline.

These figures come from a report by Natural England ("Lost life: England's Lost and Threatened Species" [NE233]), which estimates that we have now lost 18 species of butterflies, 89 species of moths and 23 species of bees in the UK, with an estimated 75 per cent decline in honeybee numbers in the past 100 years.

Why does it matter? Insects are pollinators of about 80 per cent of all plant species in Europe, including most fruit, many vegetables and some biofuel crops. Imagine our diet without pollinators.

Prices of what we now consider ordinary food - a punnet of strawberries, beans, a pot of plum jam - will rocket.

Take bumblebees alone and look at what they pollinate - oilseed rape, field beans, sunflowers, runner beans, raspberries, strawberries, apples and currants.

Gone will be the era when most of us could think of having one, let alone five pieces of fruit a day.

This posse provides a pollination service worth up to £440 million each year in Britain alone, with honeybees, as the single most important animal pollinator, calculated to contribute £27 billion to the world economy. So we've all got to act now.

How we can help
Gardeners can help reverse this trend. Reasons for the decline in pollinators are partly new diseases (in the case of the honeybee), but more importantly, increasingly sparse foraging for these insects.

With the widespread destruction of flowery habitats and changes in land management - for example - from clovers to chemical fertilisers, there's less insect food around.

As is often quoted, it is estimated that in Britain between 1932 and 1984, we lost 90 per cent of our unimproved, flower-rich, lowland grassland, key areas for any foraging insect. The countryside in 2011 may look lush, but there's precious little for pollinator insects to feed on.

As David Goulson writes in "The Demise of the Bumblebee in Britain" (Biologist, 2006), gardens now contain more flowers than most agricultural land and, in Britain, we have a lot of gardens. They cover more than one million hectares, which far exceeds the combined area of our nature reserves.

Gardens can't provide all the answers - many species have specialised habitat requirements - but for honeybees and many other bees and pollinators, they can be a huge help.

Growing pollinator-friendly plants in our patches can make a difference. Some cultivated garden plants have limited wildlife value.

Years of selection for showy blooms can result in flowers losing their attraction to pollinators, but there are plenty of traditional cottage garden plants that are tiptop as far as these insects are concerned. Having insect-friendly plants in gardens is a win-win.

Many of the best plants for insects are also great to look at, easy to grow and flower for a long time.

Top performers
In spring, flowers are so abundant that there is not really a need for more of them to help bees. But in summer flowers may be in much shorter supply, and this is when gardens can make their greatest contribution.

I've compiled a table of these pollinator super plants, but if you only have the time or room to go for two or three, borage, lavenders and Erysimum 'Bowles's Mauve' - all pretty and easy to grow - are what you should choose.

Francis Ratnieks, Professor of Apiculture at LASI (Laboratory of Apiculture and Social Insects, at the University of Sussex) tells me, "If you grow a few plants of these three, they'll bring a lot of insect activity into your garden. I would recommend planting them in a sunny spot where you can enjoy relaxing and watching the bees and insects do their thing.

"Borage is extremely attractive to honeybees, but also attracts many other insects, including bumblebees and butterflies. As an annual plant, it very quickly grows and blooms and is probably the quickest and cheapest way to get a large patch of bee-friendly flowers into your garden.

"It self-seeds and the seedlings are easily recognised the next year, so a patch can be kept going with little effort," he says.

Lavenders are Ratnieks's second must - particularly Lavandula x intermedia. "They attract a wide range of insects and, compared with borage, relatively more bumblebees to honeybees, as well as lots of butterflies and hoverflies.

"I would say that lavender is the best perennial shrub for insects in a garden, as it is so easy to grow and maintain."

His third and final special recommendation as a butterfly plant is the everlasting wallflower, Erysimum 'Bowles's Mauve'.

"This blooms for most of the year - as it is unable to set seed - and so keeps on flowering, and is very attractive to butterflies.''

Joining the dots
It's a new year, and a time for pledges and resolutions - so let's pledge to plant a few new pollinator-friendly plants in our gardens.

If enough of us think of our gardens as food and habitat havens for our declining insect populations, then they can act like a nectar and pollen constellation, thousands of spots of life scattered across the country, every one an insect magnet.

Ratnieks's team at LASI has found that honeybees will fly up to 12 kilometres to forage; bumblebees will also fly several kilometres.

That's exciting - the idea that when you garden, you're gardening more than just your plot, you are linking with and shaping the life of everything around you.

The spokes of this huge wheel are the flight paths of the insects, like a giant umbrella radiating for miles in every direction.

Before the telegraph was invented, the beacons on every hilltop between Land's End and London would communicate one with the next, spreading a message across the country.

And we can communicate to those insects that are left, to say to them again and again: Pollen here! Pollen here!


http://www.telegraph.co.uk/gardening/gardeningadvice/8229738/2011-is-the-year-to-bring-insects-in-from-the-cold.html