Everyone is aware of the importance of pollinators for our future food security. Whilst a lot of work has been focused on bees, there is a lack of studies on the importance of other pollinators, hoverflies (Syrphidae) being one of them. One factor that little is known about is where hoverflies sit within the agricultural food web. It is unclear how predominantly hoverflies feature in the diets of their predators and which predators are providing the strongest selection pressures on hoverflies. This is necessary information to know should conservation measures be needed for hoverflies in the future. Hoverflies are also a Batesian mimic. Their black and yellow colouration allows them to resemble bees and wasps in order to gain protection from predators that think they are harmful. However, this resemblance is often imperfect. A better understanding of the main predators of hoverflies will provide more information about the main selection pressures that could be driving this imperfect mimicry.

A common hoverfly Episyrphus balteatus seen in a field margin at Boothby, my main field site (left); wheat will continue to be farmed at Boothby for three years (centre), but an increasing number of habitat patches will be left fallow as the rewilding process begins (right) (photos: Lucy Baker).

My project aims to use some novel methods to determine the ecological interactions between hoverflies and other species. I hope to use immunological methods to identify wasp and bee sting antibodies in bird blood samples. I will use this information to identify which bird species provide the main selection pressure on hoverflies and therefore which species may be able to learn to avoid the black and yellow warning colouration of hoverflies, wasps and bees. I will also be using eDNA methods to analyse the gut contents of some known hoverfly predators, such as birds, wasps and small mammals, to determine how much of the diet of these species hoverflies contribute to, and whether this changes throughout the seasons. This work will be carried out at a new rewilding site in Lincolnshire. This will give me the exciting opportunity to see how hoverflies, their predators, and the insect community as a whole, changes as rewilding progresses.