Exactly a year ago yesterday Jeremy wrote a post about the dollar value of pollination as an ecosystem service. Now comes an article in Gaia which argues that previous criticism of such valuations in the same journal are unfounded. ((Alexandra-Maria Klein, Roland Olschewski and Claire Kremen. 2008. The Ecosystem Service Controversy: Is There Sufficient Evidence for a “Pollination Paradox� GAIA 17/1:12–16.)) A year is a long time in science.
The criticism in question was based on the observation that “crops depend on pollinators but crop yield does not necessarily depend on pollinators as other factors are likely to limit crop production.” Jaboury Ghazoul called this the “pollination paradox” ((Ghazoul, J. 2007. Recognising the complexities of ecosystem management and the ecosystem service concept. GAIA 16/3: 215–221.)) in an article which argued that it is impossible to value ecosystem services individually.
The authors of the latest paper dissect the situation with coffee and almond and conclude that “there is currently no evidence for a pollination paradox.” However, they do say that recent figures for the monetary value of pollination may well be media-driven overestimates. Even the often-seen figure that “one third of the caloric value of our food is derived from animal pollination … is still not well supported.” That pollinators are important to food production is not contested. But how important is perhaps not as easy to calculate as has been made out.