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:

• Holly Speckle fungus, Trochila ilicina (a tiny fungus that only grows on dead Holly leaves)
• Lesser Thorn-tipped Longhorn Beetle, Pogonocherus hispidus
• a fly, Sylvicola cinctus
• Holly Leaf-miner fly, Phytomyza ilicis
• a flower bug, Anthocoris nemoralis
• a flower bug, Anthocoris nemorum
• Common Rough Woodlouse, Porcellio scaber
• Walnut Orb-weaver spider, Nuctenea umbratica

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 ...

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:

• Buglife
• Ragwort Facts website
• Butterfly Conservation (Scotland) factsheet (pdf download)
• Ragwort hysteria blog
• DEFRA Code of Conduct (pdf download)

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 JNCC “Conservation 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.

funding for work experience with invertebrates and mammals

The People's Trust for Endangered Species is awarding funding for students/recent graduates who wish to gain experience by taking up an internship with conservation or research organisations - details available here.

For work with invertebrates, two internships are available this year, deadline for applications is 15 June 2009. Mammal internships have been allocated for 2009 but will be available again in 2010 (I see that there are seven mammal internships available, which is a bit unbalanced given the relative number of species to choose from, but far be it from me to criticise funding for worthwhile causes!).

(I'm indebted to the Amateur Entomologists' Society for information on these awards, via the AES Twitter feed.)

Award for David Lonsdale

I'm delighted to hear that David Lonsdale has been awarded this year's Marsh Award for Insect Conservation. Many years ago I volunteered as Conservation Officer for the Amateur Entomologists' Society, under David's guidance, and have fond memories of his friendly supervision, his expert and detailed knowledge, and his untiring dedication to the cause of conserving invertebrates. Strong memories also of his beady eye for any deviations from good English and scientific accuracy!

David is still active within the AES, editing their Invertebrate Conservation News among other activities, and also supports the Ancient Tree Forum and Buglife, among others. He (along with Reg Fry) was instrumental in getting the first book published on insect conservation in the UK, the AES's "Habitat Conservation for Invertebrates - A Neglected Green Issue" (1991).

This award for David is thoroughly well-deserved, congratulations, and long may his inspiring work continue.

Ask your MP to support Butterfly Conservation

Butterfly Conservation are asking for help to ensure all MPs are aware of an Early Day Motion highlighting butterfly declines:

Members of Parliament have registered their alarm at the decline in butterfly numbers and said a big thank you to all the volunteers who participate in UK Butterfly Monitoring Scheme.

More than 50 MPs have signed an Early Day Motion tabled by the MP Bob Russell, who represents Colchester and is a long-time Butterfly Conservation member.

It states that:

"This House registers its deep concern at the decline in the butterfly population, with numbers reported by the charity Butterfly Conservation to be at their lowest for 25 years, with the small tortoiseshell showing the biggest decline of 81 per cent; congratulates the thousands of volunteers who each year provide information for the UK Butterfly Monitoring Scheme operated by Butterfly Conservation and the Centre for Ecology and Hydrology; welcomes the comments of Sir David Attenborough, President of Butterfly Conservation, who is promoting an appeal to raise funds for the charity's Stop Extinction Appeal; and calls on the Government to promote cross-departmental policies to assist in safeguarding Britain's butterflies"

If you think this EDM should be supported, please check Early Day Motion 8 to see if your MP has signed, and if they haven't ask them to do so.

A sample letter to MPs can be found via Upper Thames Branch of Butterfly Conservation

Find out who your MP is here

cricket scores

Some good news from the BBC: the survival of the Scaly Cricket at Branscombe Beach.

(sorry about the title for this post)

Peppered Moth extinction - let's celebrate!

I've been enjoying Martin Wainwright's blog (Martin's Moths) - lots of mothy goodness but also examples and anecdotes about how moths are perceived in a wider cultural context. Martin's day job is as northern editor for the Guardian, and his latest blog post links to one of his articles, where he correlates the news that more people are living to a hundred with the decline in the melanic form of the Peppered Moth. It's a fascinating read, and full marks to Martin for getting some proper moth science into a national newspaper article.

However, the language used implies that the decline of the melanic Peppered Moth might be something to worry about - Martin's article says that the decline "looks terminal" and talks of "extinction" of the melanic form, and I've noticed similar language in other articles. I'm not sure what it means to say that a genetic variety of a moth is extinct - presumably the form could reappear if conditions change again (e.g. if sooty pollution were to return)? And in any case, the loss of this form is all good news isn't it - the reduction in this form of pollution is surely a success story? And the Peppered Moth as a species is still doing okay, thankfully.

There's plenty of actual species that are declining fast, but the evolution of Peppered Moth forms is something to celebrate for once!