Lightness falls

New research suggests that light pollution can reduce mating success in Winter Moths

Light pollution map from CPRE's Dark Skies project
Light pollution map from CPRE’s Dark Skies project

Moths are in trouble – evidence is accumulating (see Butterfly Conservation and Conrad et al. 2006) to show that many moth species are in decline, especially in the southern half of Britain. But what are the causes? Research is showing that a combination of factors is likely to be involved (Fox et al. 2014), with habitat change or loss and climate change likely to be a large part of the story. But another factor that could be impacting on moths is ‘light pollution’, the tendency for humans to want their own habitat to be lit up at night, so we can work, play and feel safe walking the streets. The night-time glow of towns and cities is visible from miles away, and even in rural areas roads, shops and houses may be illuminated.

Could all this light be affecting the lives of nocturnal creatures such as moths? It seems plausible, but it’s hard to prove, not least because the way most of us go out and look for moths is by putting bright lights out to attract them. How to find out what light pollution does to moths when they’re hard to observe in the dark?

Mating Winter Moths by F. Lamiot via Wikimedia Commons

A newly published paper (“Artificial light at night inhibits mating in a Geometrid moth” Van Geffen et al. 2015) has used an ingeniously simple method to investigate this, and the results suggest that we should indeed be worried about what light is doing to moths. Koert van Geffen and colleagues carried out their study in the Netherlands, and chose Winter Moth as their subject. Why Winter Moth? One reason why they make good study subjects is that their habits are a bit more predictable than for many moths: female Winter Moths are flightless, and one they emerge from their cocoons under ground they ascend the nearest oak tree and wait for the males to find them. And there is an established method for trapping them, by setting up ‘funnel traps’ that steer the females into a container once they climb far enough up the oak tree.

So Winter Moths are going to be climbing their oak trees, and if you shine a light on the tree the females can’t fly away. The Dutch team set up a series of different lighting regimes directed at oak trees, using green, white and red light, plus unlit trees for comparison. They counted the females on each tree, and checked them to see if they had mated. The results seem to me to be quite dramatic.

Mean number of female Winter Moths caught per night on trees with different light treatments, from Van Geffen et al. 2015
Mean number of female Winter Moths caught per night on trees with different light treatments, from Van Geffen et al. 2015

By far the greatest number of female moths were caught from the unlit trees. Of the illuminated trees, white had fewer than red, and green fewest of all. All lit trees had more moths on the shaded side than the lit side, but only under red light did even the shaded side produce anywhere near as many moths as the unlit trees. And there was a big difference in mating success: 53% of females caught from the unlit trees had mated, but only 28% of the females under red illumination, 16% under white, and 13% under green.

Van Geffen et al. also studied male moths using pheromone traps positioned under different lights. The differences here were less dramatic but still apparent, with fewest males caught under red light, more under white, more again under green, and the greatest number from unlit traps.

This is of course just one study of one moth species, but it showed that in this instance artificial light reduces the activity of female moths, and also reduces the male response to female pheromones, resulting in decreased mating success. The lights used in the experiment were LEDs with a light intensity of 10 lux – street lighting can be much brighter than this, up to 60 lux (Gaston et al. 2012).

Relatively simple and effective research, providing more evidence of the pressures on moth populations. Can we do anything to reduce the effects of light pollution? Gaston et al. 2012 review possible ways of preventing too much light escaping into the wider environment. Further useful information and advice is available from Buglife’s research and Campaign to Protect Rural England’s “Dark Skies” pages. For instance, we can reduce the intensity of artificial lighting, direct it more precisely so there is less overspill, and leave lights on for shorter periods so that they are only illuminated when they are actually needed. This not only has the potential to help wildlife, but to reduce energy use and costs as well – moving lighting in this direction has got to be a no-brainer.

By taking action at home and encouraging local authorities and businesses to do likewise we can all help shed some darkness and take moths out of the spotlight.

iSpot going mobile

With mobile devices (smart phones, tablets, pads and pods) becoming increasingly widespread, more and more people are accessing digital resources via apps and mobile-optimised websites. To explore this trend in the natural history context, the Communicate conference ran a session entitled “Apps for Engagement” (Wednesday 24 October 2012), at which I gave a brief presentation on iSpot’s approach to engaging with its mobile audience. Here are some links relating to that presentation.

To find out more and get updates on iSpot developments follow iSpot on Twitter or contact iSpot direct.

Credits: the development of the iSpot app has been led by Will Woods and Richard Greenwood, of the Institute of Educational Technology at The Open University, with input from other members of the iSpot team, and valuable feedback from people who have tested the app in its early stages. The iSpot keys project has been led by Jon Rosewell, of The Faculty of Mathematics, Computing and Technology at The Open University.

Extreme entomology at The Hollies

Having travelled to Shrewsbury last weekend to speak at the excellent Darwin Festival, organised by Shropshire Wildlife Trust and partners, I took the opportunity to do some extreme entomology. Okay, so The Hollies (next door to The Stiperstones, near Shrewsbury) is a bit higher than where I live, 350 metres as opposed to 100 m, but the altitude can’t be said to be extreme. And although a cold, gloves-on February day might not be the usual choice for bug-hunting – the temperature records claim it was 7-8 °C, but with a biting wind it felt a good deal colder – that wasn’t really extreme either, although it did make it hard to keep the beating tray steady. No, the extreme thing here was the trees I was searching for signs of insect life: a range of ancient Holly trees, some believed to be about 400 years old.

The Holly trees at The Hollies are an extraordinary range of shapes. Many are individual isolated trees that have been sculpted by wind and time into gnarled shapes that stretch and lean. There is precious little shelter to be had, either for the trees themselves, or any insects that might live in or on them, or indeed for the visiting entomologist. This must be one of the few Holly populations anywhere in Britain where the Holly Leaf-miner fly (Phytomyza ilicis) struggles to gain a foothold – I found just a few mines on one of the slightly less exposed trees.

Pogonocherus hispidus on Holly bark at The Hollies

But a lot of insects clearly do make their home here, as testified by the peppering of beetle exit holes in the trunks and limbs of the trees. And in fact the first insect to fall out of a Holly and onto my beating tray was the Lesser Thorn-tipped Longhorn Beetle (Pogonocherus hispidus). Larvae of this small (5mm) but attractive beetle develop in the small branches of a range of trees including Holly. Do have a look at these two great close-ups by John Hallmén on Flickr.

An hour or so of beating and grubbing around the trunks of the the trees produced a small list of other species:

A modest list, but not bad for a very cold February afternoon, especially as all but two (Porcellio scaber and Anthocoris nemorum) of these invertebrates are new records for the Stiperstones area, according to the useful list compiled by Pete Boardman in 2010. I find it comforting that these many of these species have probably been happily living at The Hollies for many generations, over the centuries since the current hollies started growing.
The Hollies is a Shropshire Wildlife Trust reserve and SSSI, so thankfully its special character has been recognised and is being looked after. It’s a shame that so many of the hollies have had to be fenced off, making it look rather like a tree zoo – presumably this is to prevent the trees being damaged by grazing stock. But the ancient hollies still work their magic, redolent of centuries of human interaction with the landscape. There’s more about the history of The Hollies on Sara Bellis’s blog, where she comments that in the past small boys would have been sent up the trees to collect the higher, less prickly leaves, as livestock feed. Since I was accompanied on my visit by a small boy in the shape of Kitenet jnr it’s a shame I didn’t think to put him to gainful employment for once …

Links for Oxfordshire recorders’ day

[These links were originally compiled for a workshop in Oxfordshire in Feb 2012, 
but may be of interest more widely.]

These are links to the various sites looked at during the online resources workshop at the Oxfordshire recorders’ day, organised by TVERC on 25 February 2012. Quite a few of these have appeared in the blog before (e.g. citizen science, online identification), but they’re all useful sites so no harm in repeating them.

Photos for identifying wildlife
Following discussion of the pros and cons of using digital photos for wildlife identification we spent some time exploring iSpot (you will be unsurprised to hear!), and what the site does to encourage proper documentation of photo-records and their identification. We also looked in on the iSpot identification keys.

Online recording
Next up was online recording, focusing on Indicia and Birdtrack. Like iSpot, Indicia is one of the projects from OPAL, and it provides a toolkit for adding online recording to an existing website. There are an increasing number of effective recording systems being set up with Indicia, including for the British Dragonfly Society and the BBC’s version of the UK Ladybird Survey.

Birdtrack has been around for a while now, developed by the British Trust for Ornithology and partners, and it really is a superb way of making bird records useful both to you as recorder, and to the conservation organisations that can make use of your data. I’ve only recently started adding my bird records to the site (I’m not much of a birder, so it’s not been a great loss to them!), and am really impressed with the way that Birdtrack handles a range of different types of recording, and provides excellent feedback.

Twitter, Facebook, Google+, blogs: time well-spent, or time, well, just spent?
We looked at just a few examples here including:

The Square Metre at TQ 78286 18846

As for Twitter, just leap in and have a go. I’m @kitenet if you want to follow me. I haven’t found how to make the most of Google+ yet, but I’m on there too.
Other resources
Finally, a mixed bag of other stuff:
  • lots of mapping links on my Kitenet website – grid refs, gazetteers, GIS and other gadgets
  • Nature Societies Online at the Natural History Museum – you’ll be amazed how many wildlife-related groups there are in your county
  • Biodiversity Heritage Library – great library of mostly older natural history and biodiversity science publications, mostly quite old, not only available as good quality scans but also searchable
  • Instant Wild, a well-designed and fun citizen science project that asks you to identify mammals caught on camera from around the world – addictive and useful

Spot spotted, or not spotted?

The spot in question is Lempke’s Gold Spot, a rather lovely moth named after the Dutch lepidopterist, B.J. Lempke, who I believe was the first to discover this species in Europe (it had long been known in the USA). In Britain it’s mostly found in the northern half of the country, but there are a few records for the south.

© Jim Vargo at Moth Photographers Group via EoL

Earlier today, Roy Leverton (author of the excellent Enjoying Moths) contacted me, in my capacity as Berkshire county moth recorder, regarding a potential Berkshire record of Lempke’s Gold Spot. This was published in a note by R.F. Bretherton, in the Entomologist’s Record for 1966 (available via the Biodiversity Heritage Library). In the note Bretherton refers to discovering that a specimen from his garden in Cumnor Hill, near Oxford, in 1940 had turned out to be Lempke’s Gold Spot, a species that had only recently been recognised as European at the time of the note.

I had no record for Lempke’s Gold Spot on the Berkshire database, and the species is not included in Brian Baker’s book on the county’s moths either, so this could have constituted a new species, the 638th, for the county list – always an enticing prospect! However, the question arises why Baker did not include the record in his book; many of Bretherton’s records were included, and Bretherton’s moth collection went to Reading Museum on his death, the museum for which Baker was natural history curator for many years, and retained an active interest in after his retirement. 
So I am left wondering whether Baker saw the Lempke’s Gold Spot record or specimen and rejected it, or whether it didn’t get into his book because he was simply unaware of it. The ‘normal’ Gold Spot is very similar to Lempke’s Gold Spot (sometimes needing dissection to distinguish the two), and in Bretherton’s article he states that the specimen was of a worn individual, so there is an element of doubt.
What all this adds up to is that, unfortunately, the verdict has to be “not proven”, and the idea of Lempke’s Gold Spot being a Berkshire moth must remain an intriguing possibility. If only we could travel back to 1940 and have a look round at the habitats then available.

Wildlife, citizens, science – Darwin Festival Feb 2012

Here are some links to do with citizen science and (mostly) wildlife recording, compiled to support a ‘Café Science’ event I’m presenting at the Darwin Festival in Shrewsbury, 17 February 2012.

Citizen Science (CS) projects, entirely online:

  • Herbaria at Home – museums and BSBI in an effective partnership to recruit help with digitising data from plant specimens (UK)
  • Cornell bird identification – innovative project to get people to ‘train’ an online identification system (USA)
  • WhaleFM – help categorise whale songs (international)
  • Instant Wild – help identify mammals recorded on-camera (international)
  • Zooniverse – collection of astronomical CS projects (universal)
  • Mappiness – uses apps to get people to record how happy they are at particular times, intends to look at whether being out in green space improves happiness [of course it does!], among other aims (UK)
Real-world projects with clever online elements:
Thanks to XKCD
  • Evolution Megalab from The Open University – main project has finished but you can still use and contribute to the website
  • Nature’s Calendar – you can contribute records of wildlife seasonal change, and also explore the records already online via some ingenious interactive maps (UK)
  • OPAL surveys – well-designed environmental surveys with online data entry and analysis (UK)
  • Your Wild Life – fun projects looking at wildlife (some of it at micro-organism level) in our homes and on our bodies – armpit biodiversity anyone? (USA)
CS record-breakers:
Wildlife survey CS projects mentioned in the talk:
Other:

Ragwort: what a fantastic plant for bees

Ragwort was in the news again earlier this year. I got interviewed on local radio about its value for moths (not a very rewarding experience, since the presenter seemed unable to get past his amusement at the idea of anyone actually being interested in moths). And environment minister Richard Benyon attracted a bit of attention with some ill-conceived Facebook comments about his hatred of Ragwort. Shortly after that episode, I happened upon this clump of Ragwort in full flower in the middle of one of my local SSSIs:

How many bees can you see on the flowers?

There were at least 50, which I’ve carefully highlighted in the second version of this photo, and they were having a fine old time necking nectar and perusing pollen:

On this occasion I didn’t capture any to check the species; there were several involved, but I’m pretty sure that many of them were the solitary ground-nesting bee Lasioglossum calceatum (this one, with its long antennae, looks like a male): 

Now, Ragwort can cause problems, being toxic to grazing mammals when consumed in large quantities, and where it poses a genuine risk to these animals it needs to be controlled. But in areas where grazing animals aren’t an issue, Ragwort provides a valuable resource for many, many insects, including at least 30 insects and 14 fungi that are entirely dependent on the plant, plus the huge numbers of insects that visit the flowers for pollen and nectar, as shown above.
The controversy over the rights and wrongs of ragwort has raged for years now, and the claims for its harmful effects have often been widely exaggerated. There’s plenty of good information about Ragwort available nowadays, not least in DEFRA’s own Code of Conduct, so there’s not really any excuse for continuing to demonise the plant. Like most entomologists, I remain pleased to see Ragwort in all non-grazing-mammal contexts, and hope to see many more plants covered in the buzzing of contented bees, flies, beetles and butterflies – the sheer exuberance of the bees in the photos above were one of my year’s wildlife highlights.

Good sense on Ragwort is available from:

Putting wildlife on the map

Last week I had the pleasure of teaching my first course for the fantastic Field Studies Council, at their Epping Forest centre. The day seemed to go well, and for me it was great to be out talking about wildlife-watching among the venerable old trees of the Forest.

I’ve added some of the materials from the course to a new biological recording section of my website, including information on recording, tips for photography and using keys, suggested surveys to try out, links to further resources and some field exercise sheets (downloadable). As ever, feedback welcome to improve what’s there and fill in any gaps I’ve missed.
While reading up for the course I went back to the late Oliver Gilbert‘s very enjoyable book The Lichen Hunters. Despite not being any sort of lichenologist myself I loved reading about the exploits of Dr Gilbert and his colleagues in tracking down unusual lichens in a range of habitats, from pristine rocks high in the Cairngorms to the ‘ancient tarmac’ of abandoned WWII airfields. Finding lichens in mountainous habitats requires impressive feats of physical endurance – anyone want to start a campaign for lichen-hunting as an olympic sport?
The book contains one of my favourite biological recording quotes, capturing some of the emotions that come from close contact with wildlife and wild places:
“You go to look for lichens and find in addition familiarity, beauty, companionship, laughter and the warmth of friends.”

New MapMate guidance

Running the MapMate biological recording database on Windows Vista and Windows 7 caused quite a few problems at first. Things seem to have been sorted out now, and if you run the latest version of MapMate (currently 2.4.0) on Windows 7 you should not encounter any difficulty.

However, problems can still arise with older versions, and depending on the route you’ve taken to upgrade. I’ve just posted a new downloadable document on my website that summarises these issues and offers some guidance on resolving the problems and keeping MapMate running happily.


Please let me have any feedback you may have from using the new document – does it make sense to you? Do the recommendations match what has worked for you?

Information sources for invertebrate conservation

The following resources were compiled for the training course on insect conservation that I led for BBOWT in March 2010. Course participants may also like to join the free mailing list for the Buckinghamshire Invertebrate Group.

Books

  • Dennis, R.L.H. 2010. A resource-based habitat view for conservation – butterflies in the British landscape. Wiley-Blackwell, Chichester. [A densely technical read, but full of insight into the ways in which butterflies interact with their environment.]
  • Fry, R., and Lonsdale, D. 1991. Habitat conservation for insects – a neglected green issue. Amateur Entomologists’ Society. [Contains lots of good information, but not as easy to use as Kirby’s book, and currently out of print.]
  • Kirby, P. 2001. Habitat management for Invertebrates – a practical handbook. RSPB, Sandy. [If you only want one book on invertebrate conservation, make sure it is this one!]
  • Thomas, J., and Lewington, R. 2010. The butterflies of Britain and Ireland (second edition). British Wildlife Publishing, Gillingham. [A fully revised edition of this classic book, with excellent summaries of the latest research into butterflies and their habitats.]

Selected British Wildlife articles

  • Alexander, K., Butler, J., and Green, T. 2006. The value of different tree and shrub species to wildlife. British Wildlife 18: 18–28.
  • Brooks, S.J. 1993. Joint Committee for the Conservation of British Invertebrates: Guidelines for invertebrate site surveys. British Wildlife 4: 283–286. [Also reprinted as AES Leaflet 38, Site survey guidelines, see http://is.gd/9HcbG].
  • Key, R.S. 2000. Bare ground and the conservation of invertebrates. British Wildlife 11: 183–191.

Online resources and downloadable reports
The Amateur Entomologists’ Society has an overview of insect conservation and guidance for insect-friendly gardening.

Buglife, the Invertebrate Conservation Trust, has some excellent resources on its website, including online summaries of its report on Managing priority habitats for invertebrates.
See also Buglife’s perspective on Ragwort and its control, and the series of farm habitat leaflets.

Butterfly Conservation has a habitat advice page with lots of downloadable leaflets on particular topics. Many of their other reports can also be downloaded.

The British Dragonfly Society has an online version of its Managing habitats for dragonflies leaflet; also on its website are “Management Fact Files” for the rarer species (look for the “MFF” links).

The Code for insect collecting is available from Invertebrate Link, and some of their other publications are hosted by the AES.

Natural England makes a range of reports and leaflets available, including:
Organising surveys to determine site quality for invertebrates [short report]
Grazing Heathland: A guide to impact assessment for insects and reptiles [excellent, although lengthy, review of the factors that should be taken into account before implementing a grazing regime]
The butterfly handbook: general advice note on mitigating the impacts of roads on butterflies [report]
Help save the Bumblebee … get more buzz from your garden [leaflet]
A review of the invertebrates associated with lowland calcareous grassland
A review of seepage invertebrates in England
Brownfield: red data. The values artificial habitats have for uncommon invertebrates
Surveying terrestrial and freshwater invertebrates for conservation evaluation [technical report, includes description of ISIS system for assessing invertebrate assemblages]

Some of the papers in the Journal of Insect Conservation are freely available online, as are some in Insect Conservation and Diversity.

Conservation statuses for invertebrate species
Information on conservation statuses is dispersed and confusing, but here are the main sources. The nearest thing there is to a complete listing of all species statuses, including invertebrates, is to be found in the JNCCConservation Designations Spreadsheet”, a large file (last updated on 23 November 2009).

This includes species listings for BAP priorities, Red Data Books, Nationally Scarce, legally protected and some others. It needs using with care, as the various statuses have been applied at different times (some are now out-of-date) and using varying criteria. The major omission is national statuses for moths, which have never been formally published by JNCC, despite being widely used for many years. The best source for these is: Waring, P., Townsend, M., and Lewington, R. 2009. Field guide to the moths of Great Britain and Ireland. British Wildlife Publishing, Gillingham.

JNCC have very recently published a revised Butterfly Red List for Great Britain, which is not yet incorporated into the above spreadsheet.

Many of the statuses in the above spreadsheet were originally published in the series of Reviews that JNCC have published. These generally include a good summary of what was known about the distribution and ecology of the rarer species at the time (but some are now rather out-of-date). The older, hard-copy reviews are listed; the latest ones can be downloaded.

The British Dragonfly Society has further information on dragonfly and damselfly statuses, including regional priorities.