Wednesday, 28 June 2017

An exemplar of watch and record


This last weekend I visited John Bridges whose spectacular stacked shots adorn the UK Hoverflies Facebook page. John has been a passionate photographer for decades but as his mobility diminishes he has had to adapt to an increasingly difficult situation. It is hard for those of us who have no mobility problems to understand what it is like to have to stop every 20 or 30 yards to alleviate pain in one's legs; yet this is what John battles with each day. Nevertheless, he is dedicated to his cause and has developed an amazing ability to record hoverflies by photography and then retaining specimens for microscopic examination. In doing so, he has generated some impressive species lists for four or five locations within a five mile radius of his home in County Durham. The combined species list for these sites is now over 100 species, which that far north is impressive by any measure.

What really struck me about John's sites is how 'ordinary' they are! I don't mean that in a disparaging way – quite simply, they are sites that might be encountered in many urban and sub-urban settings. They are not top-quality nature reserves but include an urban playing field, a well-used plantation woodland that is afflicted by teenage firebugs and a steam down what appears to be a spoil tip. That said, two of them are a shade unusual because they lie in close proximity to the wonderful Durham coast where major efforts are ongoing to re-wild the land immediately to the rear of the Permian limestone cliffs. They include sections of old/ancient woodland that forms part of the classic 'Dene' landscape of the Durham coast: deeply incised wooded stream valleys.

John Bridges at work on the margins of the famous 'Dandelion Field' in South Hetton

John making best use of 'old faithful' at Grants Houses - a busy footpath that is a pretty familiar urban setting.
John's lack of mobility means that he cannot stray from the path and has to keep to a radius of perhaps 100 metres of his car. His limited mobility means that he pursues hoverflies in the full gaze of the public and is obviously a well-known local feature. Everybody knows him and stops to say hello. Whilst this approach to wildlife recording might not be everybody's cup of tea, it is one that might be followed by other people with disabilities.

I would really like to see a project developed to encourage the disabled to develop similar skills and interests: maybe a joint venture between wildlife organisations and a disabled charity? I think there is potential to develop a project that would attract HLF funding and might make a real difference to the lives of people with physical disabilities. In doing so, perhaps it would also alleviate some of the mental disability that can accompany physical problems. If somebody picked up the baton, I think it is essential that the project had at its heart a focus on helping the disabled as much as to improve biological recording. John has shown what is possible; perhaps others will follow his lead.

Damp situation at Horden with Equisetum telmateia - usually a sign of base-richness that can be great for soldierflies.

Sunday, 18 June 2017

What is involved in running a recording scheme?

Yesterday, a post on the UK Hoverflies Facebook page drew my attention to the possible need to set out what is involved in running a recording scheme. As a result, I wrote a quick list and then organised it according to a set of sub-headings. The list was quite a surprise to me because it really highlighted the depth and breadth of what was involved. My list covered all the jobs on the FB page and the others that go on in the background and comprised the following:


Identification service
  • Provide IDs for UK Hoverflies  and UK Hoverfies Larval groups .
  • Respond to ID queries by e-mail and by flickr pages.
  • Provide specimen identification service for non-academic recorders.
  • Provide specimen identification service for Universities.
Data management
  • Extract data from FB page- maintain yearly spreadsheets.
  • Chase posts that lack data.
  • Scan FB page each day to ensure all posts have been noted and responded to.
  • Trawl Flickr sites for records.
  • Trawl iSpot for data.
  • Check grid references and dates to make sure these are correct (get quite a lot in the sea!)
  • Digitise card data and e-mail lists to spreadsheet for upload to database.
  • Validate iRecord data.
  • Check over (validate) incoming spreadsheets and format them for upload (all sorts of permutations, including converting word files to spreadsheet).
  • Import data into HRS database.
  • Supply data to research groups and NBN.
General management
  • Provide sense of direction for the HRS.
  • Manage applications to join FB group.
  • Respond to e-mail enquiries from students and research groups – technical advice.
  • Develop & manage HRS website.
  • Manage applications to join HRS website and eliminate spammers.
  • Publicity for the Scheme .
Feedback
  • Prepare intermittent feedback for Facebook group, including annual report.
  • Provide detailed responses to significant questions on FB concerning datasets/ecology etc.
  • Write HRS outputs (e.g. atlas) and evaluate maps to identify questionable records .
  • Write newsletter items (2x per year).
  • Conference presentations and talks to local societies.
Training
  • Collect and prepare specimens for running training courses.
  • Act as interface with centres that want to run training courses.
  • Organise travel and accommodation for training courses.
  • Run training courses.
At the moment we have a team of eight: Ian Andrews, Stuart Ball, Joan Childs, David Iliff, Judy McKay, Ellie Rotheray, Geoff Wilkinson and, of course, me. Looking at what we do at the moment, it strikes me that the HRS has grown in a way that it is now analogous to a small society such as BWARS. The main difference is that, because we are not a subscription society, we don't have formal 'positions' that have to be filled. That is both an advantage and, possibly, also a drawback. On the plus side, we don't need formal officers such as 'secretary' or 'treasurer'; nor do we need committee meetings that are often highly time-consuming. On the downside, how do we ensure that there are democratic provisions so that the scheme does not become a personal fiefdom?

I am acutely conscious that I currently do a lot of the 'leadership' but that is by default and because I am naturally 'bossy'. It seems to work at the moment, but it also leaves a big question mark over the long-term organisation of the scheme. Stuart and I have now been at the helm for 26 years and we must start to think about a succession plan.

When we took on the scheme, it was moribund: the previous scheme organiser had retired and nobody had stepped forward to take over. Graham Rotheray took on the newsletter editorship (now David Iliff) but the scheme effectively died. At the time, recording schemes were a bit of a peripheral adjunct to wildlife conservation, but they now play a central role in the development of reliable wildlife data. The bigger schemes are mainly linked to formal societies (e.g. dragonflies and aculeate Hymenoptera). The HRS has links to Dipterists Forum, but the Forum has no say over the future of the scheme. This lack of oversight can be a problem because there is no way of replacing a scheme organiser who has ceased to drive the scheme. In the case of the HRS, we cannot afford to let things drift: hoverfly recording is so central to various initiatives, not least current interest in pollinators.

That makes me start to ask whether we should formalise the Scheme into a Society? My question at the moment is rhetorical, but it has a rationale. What happens when somebody wants to step down from a role? In a society, there is a mechanism for advertising for a replacement and a democratic process for making new appointments. In an informal recording scheme there is no such process. Who actually has a say in the replacements? Also, if there are formal roles, these can be quoted in people's CVs. This may be important for potential recruits amongst the younger generation who obviously need to show that they are doing something if they take on a role that may help to propel their career.

I leave this analysis as food for thought, but may return to it in due course.

Saturday, 17 June 2017

An insight into a day's square-bashing


For those who are unfamiliar with the concept of square-bashing, I thought it might be instructive to show how I approach the subject. The map below depicts the route I took on 9 June between Mallaig and Fort William. It involved a total of ten stops, mainly on roadside verges as real 'sites' are often hard to come by. Where I can, I try to stop by a stream or woodland so that there is potential to collect Nematocera for the Cranefly and Fungus Gnat schemes. In other places I stop for a matter of minutes when I spot somewhere that might yield a few hovers: after all, every record counts!

Map 1. Locations of sampling points when square-bashing on 9 June 2017. The first five sites took approximately 3 hours and the remaining sites were visited quickly on the return trip. I arrived at site 1 at around 10.15 and headed for home from site 10 around 3.45, reaching Kingussie at 5.45. The total round trip was about 180 miles. In the process, 6 ten kilometer squares were visited and a small number of hoverfly records was generated.
On this day, my aim was to cover part of the west coast that is very poorly recorded. The day was not ideal – a mixture of sunshine and showers – and there were very few nectar sources. So, apart from checking out the occasional roadside Rowan, it was a matter of sweeping to generate the majority of records.

Even so, I did find two very nice localities. The first was a lovely iris flush running to the shoreline, which is very characteristic of the west coast of Scotland Location 6 (photo 1); the second (Location 9, photo 2) was a delightful section of stream with adjacent meadows covered in pignut and with localised patches of brambles and dog rose. Both were pleasant and the second site yielded a reasonable list of hoverflies. Nevertheless, hoverflies were thin on the ground and I did far better for Nematocera.

Photograph 1. Flushed shoreline with iris beds abutting saltmarsh in a continuous transition.


Photo 2. Damp meadow with bramble and dog rose.


When recording Nematocera I simply hoover up everything that flies like a cranefly or gnat and then sort them when I get home. I often end up with a pooter full of small flies and refer to it as 'black grot' – which is frowned upon by Peter Chandler as he loves fungus gnats. Photographs 3 and 4 show the results – the pile of specimens for sorting, and the subsequent piles of gnats and craneflies. I'm afraid neither shot is terribly good as it was taken in the rather restricted light of my hotel room and there was probably an element of camera shake given long exposure time (I'm no photographer!). Out of this morass I also identify what I can from other families, and pin a small amount of specimens for identification in the winter (or a winter!). The end result often yields records of Lauxaniidae, Empididae, Dolichiopodidae, Tephritidae and Larger Brachycera, so lots of schemes benefit in the long-run.

Photo 3. Sample of flies collected before sorting. Whilst predominantly Nematocera (standard bird-food) there are also a range of other families and Orders, with a large green sawfly prominent on the right hand side, and several yellow Lauxaniids in the pile.

Photo 4. sample of Nematocera separated into craneflies and fungus gnats.
This is the sort of recording that others might wish to try. It is arguably the most effective way of making sure that one uses one's time efficiently and makes sure that as many schemes as possible benefit from what is a very expensive trip. I will post more on the results when I get data back from Alan and Peter.

Low-hanging fruits


It has always struck me that people such as me were probably born in the wrong century. So much is now known about the natural world that the cutting edge of ecology lies in DNA bar-coding and ecological modelling. The straightforward natural historian has a rather constrained palate and, although we might be just as competent as our forebears, our mark on history will be far less pronounced.

I am one of the lucky ones. I got into hoverflies at a time when they were still relatively unknown. By dint of good fortune and hard work, I have managed to make my mark in traditional aspects of natural history: expanding our understanding of the distribution and ecology of a charismatic group of animals. I cannot claim to have done this alone! Without Stuart Ball's phenomenal brain, I would never have made as much of the subject. But, this has left me wondering what there is to draw in the next generation? Where are the big gaps that they can address?

Natural history has evolved and will continue to evolve. New 'names' will become the leaders in the field, but they need a niche to get established. If the easy niches are filled, then how do they make their mark if they are not blessed with mathematical or computing prowess? Some may find potential in organisms that hitherto have received much less attention, but many of these animals are unlikely to gain wider attention, so there will doubtless be space to grow skills and to occupy the inquiring mind.

BUT, we do still need these brains to continue to look at popular taxa. Monitoring changes in animal and plant abundance and distribution is a fundamental part of monitoring the health of our planet. We need this as never before. Populations of invertebrates are declining at a frightening rate and we need to be able to articulate this and trigger changes in societal behaviour before the World becomes a dull and monotonous place that is devoid of those bright flashes of excitement.

We must therefore make space for the young and we need to give them the tools to get excited and committed. I see this as absolutely essential if we are to give recording schemes long-term sustainability. In this respect it seems to me to be essential that those of us who are well-established should be mentoring our possible replacements. We need to be thinking about the unanswered questions that could be tackled by our potential replacements. So, here are a few ideas:

  1. Developing detailed habitat-specific assemblage data. We have a broad picture of what occurs where, but can we start to determine whether there are particular levels of assumed phyto-sociology that are relevant to hoverfly populations?
  2. Understanding localised abundance of hoverflies and how this fits into modern thinking about 'landscape-scale' habitat restoration?
  3. Investigating mate-searching strategies – can we develop a clearer picture of the strategies species use, so as to understand the 'guilds' of behaviour. I think there are essentially three strategies: Territorial, Lekking, Active Searching. Some of these can be broken down into sub-classes. For example territorial species may occupy air-space or a vantage point. Do such species do both?
  4. Investigating new ways of identifying live animals. I think there is an awful lot still to do. We have grown used to the characters developed by past taxonomists that are based on preserved specimens and designed for identifying preserved specimens. BUT, live animal taxonomy IS different and to some extent unquantified and in need of description.
  5. Linking DNA analysis to high resolution morphological analysis to determine whether there are good characters at high magnification that will help to resolve conundrums in species determination.
  6. Understanding the way hoverflies (and other invertebrates) use the landscape matrix to disperse. What are the impediments to dispersal and at what scale do they become significant?
  7. Understanding host-parasite interactions. Each year there are differences in the abundance of individual species. Some of these differences may be climatic, but are there examples of parasites acting as a brake on populations? Intuitively, it seems likely that there are, but do we really know what they are? (this one could be nice for people who are interested in rearing larvae).
  8. Some basic ecology – finding larvae of species whose larval stages are as yet unknown. There are, I guess, 80-100 species in this category in the UK.
  9. Investigating the impact of altitude and micro-climate at a local scale to help to determine more about landscape changes that might be made to improve hoverfly abundance in the uplands.
  10. The value of different woodland types and layouts in uplands. This could be very valuable in helping to shape land management policies as marginal land becomes economically inactive.

This list was constructed after relatively little thought. Doubtless it could be expanded many times over, and critics will immediately say that I have not mentioned pollinators. I have not, for very good reasons: there are plenty of pollinator initiatives, but hoverfly ecology and taxonomy is about so much more than plant pollination! Equally, somebody will doubtless say that other elements of the list are already known; perhaps they are, as I cannot claim to be the font of all knowledge. But, if they are, then we need to make sure that the information is readily available to help policy-makers and practical ecologists use this information to conserve the natural world.

Tuesday, 13 June 2017

Square-bashing in Scotland - some basic statistics

Between 31 May and 10 June I made my way through Scotland, staying at four localities: St John's Town of Dalry, Moffat, Tarbet (Loch Lomond) and Kingussie. Conditions were far from ideal, with several spells of wet weather and most of the time there was a risk of rain. This severely attenuated what I had intended, especially my wish to do some serious recording at Rowan in the Spey Valley. It meant that I spent far more time sweeping and relatively little time watching Rowan flowers. The records reflected this, with Bacchines and Chrysogastrines dominating the catch Table 1).
Table 1. Composition of the records at Tribe level.

The dominant species in most samples were the genera Melanostoma, Platycheirus and Sphegina, which is not entirely surprising bearing in mind that sweeping tends to yield far more of these genera than basic visual searches. Generating a decent list does, however, involve retaining quite large numbers of specimens because there is always a dominant species and a tail of species that are far scarcer. The lists tell their own story, with good representation of species in Platycheirus, including many of those that one sees relatively infrequently further south (Table 2). One that I would single out is P. podagratus, which I think is a relatively early species and was probably on the wane when I arrived. My records mainly comprise females, so I suspect males were substantially over.

What is especially noticeable from the records is the relative lack of Syrphini, which are far more likely to be recorded as flower visitors and by active searching. Similarly, the Cheilosini were relatively poorly represented; I think for similar reasons.

Table 2. Species list for the trip, with numbers of records (record = occurrence of individual genders, so the actual numbers will be lower)
The final tally of coverage was relatively good, with 49 10km squares visited (Figure 1). Had conditions been better I would have expected the coverage to have been closer to 60 10km squares and a lot more records, but I made up for the lack of hoverflies by recording other taxa. There are a lot of fungus gnats and craneflies for identification by Peter Chandler and Alan Stubbs, and I have lots of sawflies, a few beetles and a scattering of other Diptera families to deal with. So, overall, the trip should have been reasonably productive. I will write more on other aspects of the trip in due course.

Figure 1. Coverage at 10km resolution