My name is Savi Raghuraman. I am an undergraduate honors student in Michelle Sing's lab. and I'm also a work-learn in the Spencer entomology collection at the Beaty Biodiversity Museum.

My research focused on what determines hoverflies that we see in Urban Gardens. I wanted to see if the plant composition of small Urban gardens around Vancouver influence what hoverflies could use as habitat. So I chose 12 very small gardens, some of them were traffic circles or on street corners and all of them were maintained by people living in the neighborhood. I collected hoverflies there over the course of a summer and identified the species that I found and I ended up finding about 30 species across the gardens. So I found that yes, these Gardens are supporting diversity of hoverfly species in urban environments.

Hoverflies are fly pollinators that visit flowers as adults. A lot of them mimic bees and wasps, which is an evolutionary advantage that helps them avoid Predators who think that they sting when they actually can't sting. The way we recognize them is usually in their adult form, but as larvae they have a lot more variety. So some hoverflies live in aquatic habitats and feed on decaying organic material, others live in the soil and feed on plant roots, others can provide pest control by feeding on aphids or other small insects. And from there they pupate and then turn into adults. So from their entire life history the stages are really very different.

Most flowering plant species require some sort of animal to transfer pollen between their flowers so that they can reproduce, and so without pollinators, we wouldn't have much of the food that we eat, and we wouldn't have much of the incredible diversity in flowers that we see today. Pollinator diversity is really important because different pollinating insects for instance have different life histories. So for example, hoverflies-- they don't need to nest. This is different from bees which typically require nests. So when we have multiple pollinator groups, it helps buffer pollination services in times or places where one pollinator group might be struggling to ensure that plants can still um have their reproductive needs met.

I mean one really good starting point is to have flowers. Lawns are not going to support as many species, but even if you have a lawn and you let the weeds grow, that's better than no flowers at all, and hoverflies I I have seen them often feeding on dandelions. Spaces that are free of insecticides are important because if the larvae are predaceous on other insects they need other insects around to eat and they also aren't very mobile so they can't move away from a habitat that's dangerous to them.

For hoverflies that grow up in the water, they need lower levels of contamination from pollutants or insecticides. Although the evidence isn't clear whether native plants are better than non-native plants for other pollinators, native plants are important. When I was in the field, I saw so many species of wasps and pollinating beetles and herbivorous insects as well, so it's clear that if there's this diversity of hoverflies there's a lot more diversity of other insects too. And so having this habitat with a variety of resources, can support a variety of insects.