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.