Rare plant’s need for native pollinators threatened by invasive plant-pollinator relationship

Chloropyron maritimum ssp. maritimum
visited by Bombus californicus.
Photo: Kylie Etter

By Etter et al.

Many flowering plants need pollinators like bees to reproduce. But when new, non-native plants move into their habitats, they can disturb these important relationships. One rare plant that is reliant on pollinators is Chloropyron maritimum maritimum, which is found in salt marshes in Southern California, USA and Baja California, Mexico. Unfortunately, these marshes are being invaded by a non-native plant called Limonium duriusculum.

To see how this invasion affects the rare plant, we watched which insects visited which flowers, studied the network of plant-pollinator relationships, and tested what happened when L. duriusculum was removed in small areas.

We found that only native bees visited C. maritimum maritimum, and not very often. In contrast, L. duriusculum was mostly visited by two non-native insects, which didn’t once visit the rare plant. Removing L. duriusculum didn’t increase visits to C. maritimum maritimum, but it did make the overall pollination network stronger and more connected.

In the future, we hope to both remove larger areas of the non-native plant and check to see if there are good places nearby for the native bees that visit C. maritimum maritimum to nest. This could help protect the few remaining pollination interactions the rare plant still has.

 

Read the scientific article in JPE!