Moths beat bees on pollination, sometimes

The collective imagination, at least for many, associates the word pollinators with the image of a bee. And yet, plant you go pollinator you find. So for example, if we are talking about blackberry brambles in southern England, the title of doc pollinator would go to the moths: they are extremely productive. These diurnal insectsin fact, they would be better at pollinating the flowers of blackberry brambles than diurnal insects. The discovery comes from the University of Sussex, England, thanks to the work of three researchers who have observed the behavior of diurnal and nocturnal insects on some brambles of blackberries.

“Moths are important pollinators, but they are very underappreciated and understudied – explained Max Anderson, first author of the paper – Most research on pollination tends to focus on insects that fly during the day, with little attention to what it happens at night”. And instead, when you go to study what happens at night, you discover that, in some cases, there are particularly active pollinators, even if they visit the flowers less than diurnal pollinators such as bees. It is precisely the case of mothswhose behavior the researchers followed within three days, monitoring it thanks to the use of some cameras, which filmed the insects’ flights on the flowers of some brambles in south-eastern England.

To distinguish the pollinations carried out by bees or moths, the researchers used sacks to shelter the flowers at different times: in some cases they were left free only during the day, in others only at night. Other flowers, on the other hand, were kept sheltered during the three sampling days, so as to be used as a control. After these three days the flowers were sampled, the stigmas were extracted – the part of the flower responsible for receiving the pollen – and in the laboratory the researchers measured how much pollen they contained. In this way, by combining this data with the images captured by the video cameras, and calculating the exposure time of the flowers to the insects, they were able to estimate the efficiency of the various pollinators.

The results showed first of all a rich variety of insects during daylight hours, while at night moths dominate. But although most visits were during the day, by various insects, moths were more efficient as nocturnal pollinators. The amount of pollen deposited per hour was greatest in flowers exposed at night, the authors write Plos one.

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The results of the work essentially say two things: on the one hand they serve precisely to redeem the image of moths, important pollinators, also aided by nectar production by blackberry brambles, richer in the evening. On the other hand, the authors comment, he also underlines the importance of brambles for nocturnal insects: “Now that we know that moths are also important pollinators, we need to encourage the growth of some brambles and other flowering scrub plants in our parks, gardens, roadsides and hedgerows,” continued Anderson. And, in a period like the one we are experiencing, in which insects have been in decline for some time now, the authors conclude, it is more important than ever to prevent the situation from getting even worse.