Insect Highway Project

A monkey beetle (Scelophysa trimeni) burrowing in the disc of a daisy flower (Arctotis decurrens) while feeding photo: Julie Anne Workman, Wikipedia

The Insect Highway Project is about connecting patches of insect-appropriate plants to one another, so that insects can have a whole network of plant populations to rely on and use. This helps the insect populations to become more resilient. If one patch is affected by disease, mowing, or other threats, then they have other patches to move to. If they were isolated and rely on a single patch, then they are much more vulnerable.

Secondly, the plants themselves benefit from this because they get pollinated by a wider range of plant populations, which prevents inbreeding with only a small number of neighbours, which would make them more vulnerable in the long term.

Protecting insect species through indigenous gardens is important for the following reasons:

• They are essential foods for animals higher up the food chain such as birds.
• Insects pollinate key species including plants from the cut flower industry, food industry, landscaping industry, etc.
• The ecosystem relies on a healthy insect population as a foundation (for food, for pollination, for seed dispersal, etc).
• Bee populations are under threat from pesticide use and in many places their populations are on the decline. They need all the support we can give them.
• There are a variety of invasive insects that damage our ecosystems in Cape Town and in the fynbos biome. By planting indigenous vegetation we give the indigenous insects an edge over the invasive species.

Project status

This project is currently under development. We have been setting up a first few gardens in which we have taken insect plant species into account when deciding on what to plant. Furthermore, we are collaborating with PhD candidate Peta Brom to use her insect monitoring protocol to get a better idea of the impact of our gardens on monkey beetles.

Next steps

After we have tested which plants work well for our greening efforts and also benefit insect, and once we have gotten a better understanding of insect monitoring, we will seek funding to take this project to the next level. Our 3 year goal is to densify our existing garden network so that insect-friendly stepping stone gardens are added between our existing patches. Insects generally have a smaller range than birds, so in order for our garden network to become a corridor for insects, we need to ensure that the network becomes more dense. Furthermore, we will need to add a larger variety of plants to our patches, to ensure that there are flowering plants throughout the year.