Sampling and studying ants in the high canopy of a tropical rainforest by Kalsum M. Yusah

Entomology has always been special to me. It is one of my favorite subjects during my undergraduate study. This subject is mesmerizing and appealing. Its open a door to a diverse and complex nature of insects world. The list of entomologists through recorded history is enormous, and includes such notable figures as Charles Darwin, Jean-Henri Fabre, Vladimir Nabokov, Karl von Frisch (winner of the 1973 Nobel Prize in Physiology or Medicine) and two time Pultizer Prize winner E.O. Wilson.

Here I would like to share a study done by a young researcher Kalsum M. Yusah, from Sabah and currently she is in her 3rd year of her PhD research at the University of Cambridge,UK. Her interesting research is about ants.

Although research in the past few decades has established that the rainforest canopy harbours an exceptionally rich diversity of arthropods, we still know very little about the ecology of these important animals. This is principally because it is difficult to sample and study animals that live so high above the ground. We report here on methods that we have developed for studying ants, the dominant arthropod taxon, in the canopy of the dipterocarp forest of the Danum Valley Conservation Area in Sabah, Malaysia. We show that methods that work well on the ground need to be significantly modified before they can be applied in the challenging condition of the high canopy.

The most flexible method of accessing the tree crowns is to use the double-rope technique, and it is also essential that the scientist becomes sufficiently confident in using branch-walking techniques such that she is able not only to move freely but also to make rigorous observations within the canopy. For efficient sampling of canopy ants, fogging is a useful general method, but needs to be modified by raising the trays high into the crowns to produce a focused sample with little loss of the crown ant species or contamination by ants from lower in the canopy. Traditional baits work well in the canopy, but in order actually to collect ants at the baits, it is necessary to use a modified trap that can be closed without the disturbance caused by walking on the branch near the ants. We show in detail how this purse-string trap works. Pitfall traps can also be used in the canopy but are quite poor at collecting ants. For observing ant behaviour, we used video cameras which both reduces disturbance of the ants and minimizes the amount of time that the researcher needs to spend in the tree crown.

We present quantitative data on the effectiveness of these different sampling methods, and show that a combination of baiting and fogging appears to capture approximately 90% of the ant species in a tree crown.

p/s: Thanks for letting me share your research Kalsum. Great job! Here is a link to entomologist blogger from UKM.