A new paper in the Journal of Threatened Taxa, Vol 7, No 6 (2015) asks, and answers the question: ‘Harvesting the guano of insectivorous bats: is it sustainable?’ Investigators Thet Thet and Khin Mya Mya focused their studies on one cave, in a complex of four caves on Sudaung mountain, Sintkaing Township, Mandalay Region (21044.941’N & 96015.570’E, 314m), Myanmar.
“The licence to remove guano from the Sudaung cave complex is issued annually by the Forestry Department and has been held by one family for over 40 years. This, in itself, suggests that the rate of guano removal has not exceeded the rate of deposition, and that harvesting has been carried out sustainably. It also suggests that the disturbance associated with guano removal has no adverse effects on the numbers of bats occupying the caves. The Forestry Department does not impose a quota and the collectors remove all available guano.”
Bonus task (optional) : List possible consequences if the guano collection exceeded the rate of deposition.
Also see, cited in the paper and of poss. interest to nominative determinists : ‘Conservation ecology of cave bats. In: Kingston, T. & C.C. Voigt (eds.). [in press, sorry no link yet] Bats in the Anthropocene – conservation of bats in a changing world.’ Springer, New York. By Dr. Furey and Professor Racey.