Caterpillar Hunting...

Nicole! Glad you asked that because I didn't make that part clear. You can use them in the tropics (and we have before), but there are a few issues in the tropics to consider, that can make beat sheets less useful for what we need to do, but could still work in other cases: 1) First and foremost for our project (which catalogues interaction data), we need to ensure accurate caterpillar-host plant associations. Thus, we need to use methods that give us confidence a caterpillar came from a particular host-plant. In the tropics, vegetation is dense and plants are intertwined with each other. In that case, if we use a beat sheet, it would be hard to make a host plant association with certainty because we would not be able to determine from which plant it came. 2) Understory plants in the tropics include a lot of shrubs and young trees with few very large leaves, or are vines that are intertwined with other plants. In these cases, it is just more efficient to look under the leaves. A beat sheet could be destructive and cumbersome for plants like these. In temperate regions, in the sites I have collected, you come across relatively large and dense shrubs (e.g. Ceanothus or rabbitbrush) or trees (e.g. oaks and juniper) and beat sheets work great for these because you can hit a large area of a single plant and the robust branches will hold up to the beat sheet method. 3) It is very wet in the tropics, and beat sheets are most efficient when you can gently shake of the debris to reveal caterpillars stuck to the sheet using their prolegs. If the canvas beat sheet is wet, debris sticks and it just makes it tough to reveal caterpillars. 4) Many caterpillars we find in Costa Rica are shelter builders. These roll up leaves. a beat sheet is unlikely to work on many of these and you do not need a beat sheet to spot them. 5) Bullet ants! In Costa Rica this is an issue to consider when using beat sheet methods. 6) The first time I used a beat sheet I was in the tropics (Ecuador). We used it to hit Chusquea (bamboo. For tropical plants, like Chusquea that dominate an area, the beat sheet method can work. This is also true for many plants in dry tropical forests. . Hope this helped clarify the many uses of beat sheets!