Detailed protocols: Pan-trapping add on (European sites)

MATERIAL PER SITE:

Material provided by us (with package sent in the mail – contact susan.everingham[at]ips.unibe.ch if you would like a pan-trap package sent to your team):

  • 2 white bowls, 2 yellow bowls, 2 blue bowls, 2 red bowls
  • Detergent (biodegradable, scentless soap)
  • 4 color-marked sampling tubes (to collect the insects and send back to us)

To be purchased by each collaborator:

  • sticks and material to fasten the bowl to the stick
  • Fine-meshed sieve (e.g. very fine lace curtain)
  • 70% ethanol

BUILDING PAN TRAPS:

The pan traps can be built depending on what material is available in each region. ***IMPORTANT: the height of the bowl has to be the same height as the surrounding vegetation (upper edge of the bowl end with vegetation) ***. Any method to achieve this objective if fine. We provide some examples how this can be done (fig. 1-4).

PLACING THE TRAPS IN THE FIELD:

Always group all four colours together and place them diagonally opposite in your site at least 6m apart

Figure 5 – diagram of each comparaitive study site with plots and pan traps located throughout.

PREPARE THE PAN TRAPS

Prepare the soapy water by adding 2.5 ml of the provided soap to 2L water. Stir gently (no foam!). Fill two thirds of each bowls (ca. 350ml) with the soapy water. If it is very sunny, fill in as much as possible as it otherwise will evaporate. Leave the pan traps for 48h.

LABELLING THE SAMPLING TUBES:

Label each tube (with colour corresponding sticker to the correct pan trap colour) as follows:

REMOVING THE TRAPS:

Return to the traps after 48h and remove the traps. Pour the soapy water with the insects through a fine-meshed sieve (this must be a very fine sieve as to ctch all of the insects, even the small ones). Transfer the remnant (insects) from the sieve into sampling tube with the respective color sticker of the pan-trap. The insects from the two traps of the same site with the same colors are pooled into the same sampling tube. Fill up the tube with 70% ethanol. Send the sampling tubes (4 per site) back to Bern.

Send your tubes back to Bern with all other invertebrate, soil and plant samples.