Recent research, headed by David Kleijn of Alterra and Wageningen University, shows that the links between species diversity and pollination are much more complex than previously supposed.
Their work suggests that rare species barely contribute to pollination and that the international debate on biodiversity conservation the current focus on ecosystem services may have a negative effect on the argument for the protection of rare species.
In a large international project, David Kleijn together with 57 fellow researchers studied to what extent ecosystem services are a valid argument for the protection and promotion of biodiversity. The research examined crop pollination by wild bees in farming systems on five continents.
It found that wild pollinators contributed substantially to the production of approximately 20 insect-pollinated crops, including rapeseed, sunflowers, strawberries, broad beans, apples and pears. The contribution of insects to crop yield – the economic pay-off of pollination – was on average more than $3000 dollars per ha.
This knowledge may encourage producers to take measures to promote bees. “But,” says Kleijn, “most of these ecosystem services were provided by a small group of common species. Rare species barely contribute to crop pollination.”
He adds that it is fairly easy to protect common species by sowing flower strips, for example, but this is not true for the protection of rare species. “Rare species may play a less relevant role economically than common species, but this doesn’t mean that their protection is any less relevant,” he adds.