New story: Farmer wants a hive

I haven’t written for The Conversation (TC) for a while, and this article was a new experience for me: a commission via Twitter! A TC editor saw a live tweet from a talk I gave at a conference in April (where I mentioned that Australian almond growers rent honey bee hives to pollinate blossoms), and contacted me to write a story elaborating on the theme.

Read the story here, covering the basic ins and outs of hive rental, as well as the important role of wild pollinators in crop pollination, which we still know very little about. Continue reading

Crop pollination depends on wild AND managed pollinators

I just published this letter with Toby Smith and Romina Rader, in response to an opinion piece in Science back in January. The original paper argues that high densities of honey bees can harm wild pollinators (this can happen in some contexts).

It also suggests that a first step toward a conservation strategy for wild pollinators is that crop pollination by managed honey bees “should not be considered an ecosystem service” because those services “are delivered by an agricultural animal and not the local ecosystems”.

This highlights a common misinterpretation of what ecosystem services is all about. Services are delivered by interactions between species (including Homo sapiens) and their environments at multiple scales, not individual organisms or natural ecosystems. Continue reading

Flower Visitors vs. Pollinators: no evidence that honey bees are the most important pollinator worldwide

Pollination is a complex process. It’s not as easy as an insect simply visiting a flower.

This is important to remember when talking about which species are the ‘best’ or ‘most important’ pollinators. Simply observing an animal visiting a flower is not, on its own, evidence that the animal is pollinating the flower.

Many insects (and other animals) visit flowers, to feed on pollen, nectar or other flower parts. Many of these interactions result in pollination…although some visitors are better pollinators than others. Some of these visitors commit floral larceny – they are robbers or thieves (there’s a difference!) of either pollen or nectar, and they leave without pollinating. Some might even damage flower parts so much that they indirectly affect the flower’s capacity to be pollinated by other visitors.

To know for sure that an insect is pollinating a particular flower, we first need to know what kind of reproductive system that flower has. Is it male, female or bisexual (containing both male and female parts)? Can it self-pollinate, or does it need to be outcrossed to another flower or plant of the same species? Once we know this, we then need to watch the behaviour of the insect that visits that flower. Does the insect visit one flower and fly away, or many flowers in a row? Does it move between plants? Does it actually touch the reproductive parts of the flower when it visits each flower? Continue reading