Unlike animals, plants can’t move around in search of a mate, to reproduce. Therefore, plants need pollinators to transfer the male sex cells (pollen) to the female reproductive parts of flowers. This process is called pollination, and it leads to fertilization. Good fertilisation helps plants develop seeds and fruit that feed countless animals in the world, including us.
Importance of biodiversity
Pollinators drive biodiversity, and globally, nearly 90 percent of wild flowering plant species depend, at least in part, on the transfer of pollen by animals. (IPBES, 2016)
Over 75% of the world’s food crops (by type) rely on animal pollinators for yield and/or quality and these crops contribute 35% of global crop volume and represent an estimated market value of AUS$350-$860 billion.(IPBES, 2016)
Pollinators provide essential ecosystem services in the natural landscapes as well as within agricultural/horticultural and urban environments.
The ecosystem services provided by pollinators extend well beyond food provisioning. Because pollination drives biodiversity, pollinators also contribute to:
Who are the Pollinators?
The vast majority of pollinator species are wild, including more than 20,000 species of bees, some flies, butterflies, moths, wasps, beetles, thrips, birds, bats and other vertebrates.
Honey bees (Apis mellifera) are particularly important as pollinators of food crops. They are the most widespread managed pollinator in the world. It is estimated that globally, there are about 81 million hives producing an estimated 1.6million tonnes of honey annually (IPBES, 2016). In Australia, by contrast, in 2014-15 there were an estimated 13,000 registered beekeepers operating 448,000 hives (ABARES, 2016) representing around 0.5% of global managed hives.
Although the relative contribution of each pollinator varies significantly according to crop and location, crop yields and/or quality depend on both the diversity and abundance of pollinators and pollinator diversity contributes to crop pollination even when managed species (eg honey bees) are in high abundance.
Pollinators in decline
Multiple reports globally have documented widespread pollinator declines;
Global data from United Nations however suggests that overall between 1961 and 2017, there has been an 85% increase in the global population of managed honey bees. Regions where the largest population declines have been recorded are North America (-43%), Europe (-11%) , and Central America (-2%) (Karasinski, 2019)
In Australia, honey bees are so far not experiencing the kinds of losses experienced in other countries. In terms of native bees and other insect pollinators however, there is insufficient data to know conclusively what is happening, mainly because there is a scarcity of research on Australian pollinators.Anecdotal evidence suggests there may be pollinator decline here too. (How often do you clean your windscreen these days compared with 30 years ago? How often do you see butterflies relative to when you were a child?)
The lack of information in Australia highlights the urgent need for further research that monitors pollinator diversity and numbers over time. Getting involved in citizen science projects that help monitor pollinator numbers over time help to build the body of evidence needed to understand what is going on.