Some survey techniques for beginners

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I thought I'd put these notes up for people who are interested. It is adapted from a letter I sent to a scout troup who wrote to us asking for pointers on doing ecological surveys. Essentially it is a brief overview of some techniques that are easy & cheap to run with small groups (or by yourself).

First, some general points:
A good first step with any work of this nature is to contact the local environmental groups such as the Wildlife Trust. These people should be able to provide local expertise in many ways, from suggestions as to project area & targets to giving talks on various aspects of ecology. I have provided some useful addresses at the end of this letter. It must be remembered that most ecologists & field biologists in this country are very busy during the summer months, so get in early if possible.
Obtain good field guides. There is no point in survey work when you cannot identify the plants or animals involved. Collin's do a good range of guides, in particular I would recommend their guides to birds, insects & spiders. The Wild Flower Key by Francis Rose is very good for plants, although it uses a lot of scientific terms & should possibly be used in conjunction with a more user friendly guide. Skinner’s Colour Identification Guide to the Moths of the British Isles is invaluable though expensive. Lastly, Richmond Publishing’s Naturalists’ Handbooks are very good guides to different groups, such as weevils & hoverflies. These handbooks also come with some suggestions for projects, the ants book is especially good for these. An important point here is that just because a certain species is listed or pictured in a field guide it does not mean that is what you have, read the description carefully to see if there are any further points to look at.
In preference to collecting dead specimens for identification, take photographs. This is less destructive & also provides you with material for displays.

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The first stage is to determine the area to be surveyed, a farm, or garden for example. Map the area as accurately as possible, taking special care to include any potentially good spots for wildlife (ponds, hedgerows, accumulations of dead wood etc.) a GPS is very useful for this. Certain habitats will be more rewarding to the survey than others, a good thing to look for is marginal or “edge” habitat – the edge of a woodland or pond for example, or any area of scrub.
It should be recognised that, unless the area is very small, there is no chance of finding & recording every single plant, insect or other organism inhabiting your survey area, this would involve an inch by inch search of the entire farm. You can do a general survey & supplement this with detailed surveys of small plots of about 5m2. These plots can be determined randomly (e.g. pin in the map), or placed in potentially rewarding sites.
At the start of the survey it may be useful to get some targets to work towards. These may be things like identifying & measuring all the trees in the study area, seeing if there is a difference in the ground flora between different crop fields or trying to find a certain number of species of particular groups ( 6 bumblebee, 15 butterfly & 5 dragonfly species for example).

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Below I have listed a number of projects and survey techniques. They are in no particular order & I will leave it up to you to decide which, if any, should be used although I have indicated certain projects as good for youngsters & small groups.

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Hedgerow survey.
A simple project where a section of hedge is surveyed for plant species. There is a general correlation between the age of a hedge and the number of shrubs it contains. A rough but often inaccurate guide is one century of age per woody species found in a thirty-metre length of hedge.

Footpath survey.
Take a line at right angles to a footpath to about 5m either side of the path, or to the boundary. Take measurements at 50cm-1m intervals along this transect recording type of & height of vegetation. This survey is a good method to show the effects of foot trampling on vegetation. Is there a difference between a woodland path & one across fields or between a human footpath & one created by livestock? This is a quick survey that could be done in an evening.

Water Sampling.
Fish tank test kits are available from pet stores which would allow you to sample the pH, ammonia & nitrate levels of water around the study site. Are there any differences & if so, why? Is it geology, land use or some other reason?

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Bee/Butterfly Transects.
A transect is a line of survey, we have already encountered one type on the footpath survey, the bee/butterfly transect is slightly different and is essentially a walk between two points. The transect should be at least 100m long, you walk it and count what species of bee or butterfly enters your detection zone. The detection zone in an imaginary box with sides of 3-5m in front & to the sides of you as you walk the transect. A survey area the size of a farm should be able to accommodate more than one transect. Is there any difference in numbers between transects? If so, why? This technique, slightly adapted, can also be used for surveying birds.

Point Counts.
Almost always used for bird surveys, this technique involves staying in a fixed point for a fixed amount of time (20-30 minutes) & counting the birds you see & hear. You can set up a number of point counts in different habitat patches compare the results.

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Pitfall Trapping.
This is a staple method for any invertebrate survey, they are good for beetles, centipedes, millipedes, ants and gastropods (slugs & snails). There are many variations on the theme, of which I have outlined two here.
Method 1: A canister without a lid is sunk into the ground so that it is level with the soil. The open mouth should be protected by a roof of stone and wood arranged to exclude rain & larger animals such as mice & frogs. Always look at the traps each day as insects like ground beetles will devour the rest of the catch if allowed time. If they cannot be checked daily then antifreeze can be poured into the trap (with a few drops of detergent) so that anything falling in can be preserved. These traps can be placed at random spots or along a transect line like the footpath survey for example.
Method 2: Sink buckets or large pots at regular intervals (e.g. every 2m) in a line, remember to drill some drainage holes if it is likely to rain. Using a sheet of tarpaulin or other resistant fabric, create a trap line in the form of a fence running across the middle of the buckets. Ideally this should be around 10m long & 20-30cm high. Make sure the base of the sheet is buried under some soil. Any ground dwelling invertebrates, small mammals or amphibians that are intercepted by the trap line will walk along it until they fall into the pitfall. Make sure you check such traps at least twice a day or you run the risk of encountering dried out frogs & starved shrews.

Light Trapping.
For moths and other nocturnal insects e.g. caddis flies & beetles. This method works best using the right equipment which is expensive, the local Wildlife Trust should be able to find someone prepared to bring their trap out for an evening, otherwise a strong light & a white sheet can be used. This is a good evening activity as the trap does not have to be left out all night.

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Plant Colonisation.
A simple method to see what plants are able to colonise new areas. Scrape a section of ground to bare earth and survey once weekly or fortnightly to see what plants are growing. This survey plot could be returned to year after year to give a good idea of plant succession as the early colonisers are replaced by other plants.

Bat Walks.
Again this method needs some expensive equipment, in this case a bat detector. As with the light trap above, the local Wildlife Trust should know someone who could bring one along for an evening.

Sugaring.
An underused technique for attracting moths. The recipes for sugar mixture are closely guarded secrets but most involve a varying quantity of sugar, fruit scraps, molasses & stale beer or rum. Paint some of this mixture at chest height on a fence post or tree trunk. Leave it overnight & check it early in the morning to see what has arrived.

Pond Dipping.
A great activity for younger children & also a good evening activity. You’ll need some nets & some trays to hold anything you catch. If there isn’t a pond on your survey site why not create one? You can then look at colonisation in much the same way as the plant colonisation method above – it is surprising how quickly insects like pond skaters & water beetles can find & move into new habitats like this.

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Behavioural Study.
This can be difficult in a natural situation. Select an individual of the species involved, watch it for 1-2 hours & record what it is doing (sleeping, feeding (on what?), singing etc.) every 5 minutes or other suitable time period. The results can be used to determine an activity budget, in other words how much time is spent doing what?

Leaf Litter Sampling.
With a small amount of preparation this is an ideal evening activity. Collect some leaf litter from the survey site in a bin bag, set up a table (preferably smooth surfaced & white) with a strong light above one end, place a couple of handfuls of leaf litter at the end nearest the light and pick up creepy-crawlies as they move across the table searching for shade. This can be done with soil & dead wood samples as well as leaf litter.

Water Traps.
Place a bowl or tub of water with a few drops of detergent to break the surface tension in a likely spot. Flies will be attracted & caught when they land on the water surface. A nice project using this technique would be to use different coloured tubs, what colour tub attracts most flies? Are different types of fly attracted to different colours? This is a good activity for younger children & summer evenings.

Badger Watching
Your local Wildlife Trust may be able to take small groups of well-behaved children to view a badger sett in the evening.

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Equipment.
Many of the above examples require the minimum of equipment, however the following materials may be useful to obtain. I have included a couple of suppliers in the useful addresses below.
A net is an essential accessory for the entomologist; it is nearly always easier to identify an animal you have caught than chasing after it trying to see all the important features as it flies/runs away. Pond dipping nets are different from butterfly nets, being smaller & sturdier, do not give into the temptation to use one in place of the other – it won’t work.
Sample tubes are also good to have in order to hold anything caught – I usually carry at least 5 tubes for every hour fieldwork planned. Entomological suppliers have a wide range of products in this line though these can be expensive; I tend to use cheaper urine sample tubes (unused of course!). Contact your local hospital for a supplier. Plastic resealable bags are very useful for holding plant samples.
A hand lens or magnifying glass should be an essential purchase (better still a binocular microscope if you can afford it). Most of our wildlife needs a good close look if you are to stand a chance of identifying it correctly. I use a x10 hand lens for plant identification & larger invertebrates.
You may like to create a herbarium, or plant collection, for your survey area. For this you could purchase a plant press, or use some heavy books. A good way to keep & display pressed plants is to place them on a sheet of paper with all the details (species, habitat etc.) and then laminate it.
One final piece of equipment that isn’t essential but is very handy is a pooter. This is basically a collecting jar with two tubes attached to it. The end of one tube is placed near the (small) insect you want to collect and you suck through the other. Make sure you place a piece of gauze over the end of the mouth tube or you’ll end up eating your catch! There are now some electric pooters on the market but I can’t vouch for the efficacy of these.
Of course, a good deal of the equipment is quite easy to fabricate yourselves, and there are some good websites around that can give ideas as to how.

Finally, a note on data recording. Things that should be recorded include position (as a grid reference), altitude, situation (in shade, on a gravel bank, on a tree trunk etc.) and weather, if you have observed an insect on a plant record the type of plant as well. Bear in mind that you can’t have too much data – if you have it you can choose whether or not to use it later. Many companies offer recording software for this kind of project, I am sure they are very good but I use a combination of Excel spreadsheet & Access database.

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Useful Addresses

The Bug Club
Amateur Entomologists Society,
AES Registrar,
PO Box 8774,
London,
SW7 5ZG
www.ex.ec.uk/bugclub
www.theaes.org

British Entomological & Natural History Society,
c/o Royal Entomological Society,
41 Queens Gate,
London,
SW7 5HU
www.benhs.org.uk

British Trust for Ornithology,
The Nunnery,
Thetford,
Norfolk,
IP24 2PU
www.bto.org

English Nature,
Northminster House,
Northminster Road,
Peterborough,
PE1 1UA
www.english-nature.org.uk

The Mammal Society,
2B Inworth Street,
London,
SW11 3EP
www.abdn.ac.uk/mammal


The Royal Society for the Protection of Birds
The Lodge,
Sandy,
Bedfordshire,
SG19 2DL
www.rspb.org.uk

The Wildfowl & Wetlands Trust,
Headquarters,
Slimbridge,
Glos,
GL2 7BT
www.wwt.org.uk

The Field Studies Council,
Montford Bridge,
Preston Montford,
Shrewsbury,
Shropshire,
SY4 1HW
www.field-studies-council.org