March 5, 2014

Pollinator Diversity Matters!

By Lucas A. Garibaldi, Universidad Nacional de Río Negro

Wild pollination is an ecosystem service that provides innumerable benefits to our world’s agricultural systems including soil erosion mitigation and pest control for ensuring strong yields and food security worldwide. With the rise in vast single-crop systems and increasing agrochemical use, wild pollinators like bees, beetles, flies, butterflies, birds and bats have become especially vulnerable. Their numbers are decreasing in many agricultural landscapes.

Attempts to compensate for this by increasing the number of domestic honey bees does not show an increase in agricultural production (tonnes per ha). In fact, the yields of many fruit and seed crops like tomatoes, coffee and watermelon are already limited because of insufficient pollination, which suggests the importance of keeping wild pollinators on our farms.

To explore this, our international research team of fifty authors collected data at 600 locations on all continents except Antarctica. The field data from 19 countries and 41 systems contained a variety of crops including almonds, strawberries, coffee and tomatoes, and spanned a range of agricultural practices from large-scale monocultures to small, diversified farms.

In all of our study areas, the proportion of a crop’s flowers that became fruits or edible seeds were higher where more wildlife was actively pollinating the plants. Conversely, only 14% of our study sites showed this increase with honey bees. Additionally, our research shows that wild insects are twice as effective pollinators.

This loss of wild pollinators and subsequent decrease in crop yield, supports the argument for ecological considerations in sustainable agriculture, rather than conventional intensification practices. Better pollination management will lead to increased agricultural yield. This means not only relying on a single domesticated pollinator, but also incorporating wild insects for resilient farming systems. Diverse farms and landscapes that provide habitat for wild and managed pollinators are especially significant aspects that should be considered in future policy decision making.

Photo: Maj Rundlöf, Swedish University of Agricultural Sciences

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