Before you go into the field

Before visiting your study sites, you need to prepare two traps for each site at which you'll be doing the acid rain protocol. To make each trap, cut a 1 ft. x 1 ft. square of plain (uncoated), corrugated cardboard from a brown cardboard box (such as those used to ship groceries or small appliances.) You can use the corner of another box as a template to make a 90° angle in the corners. (If you are making several traps, you might like to use the first trap as a template for making the others, as we did when making our traps.) At least one side, which will be placed downward, should be free of printing or glue. It is important to use fresh traps each time. Do not reuse the cardboards.

In addition to the traps, you will need to get 1 liter of non-chlorinated water per trap that will be used to moisten the traps as they are placed. You can use almost any bottled water, but check the label carefully to ensure that the water contains no additives such as chlorine. Much of the tap water in the United States is chlorinated and shouldn't be used for our study, as it could potentially repel rather than attract the animals we want to sample.