Unlikely hero saves ecosystem from negative climate change effect

Herbivores could protect ecosystems from climate change according to researchers from the University of British Columbia. The scientists created temperature manipulated mini-marine ecosystems that either allowed limpets in or kept them out. These herbivores were found to be very important in maintaining biodiversity, especially in aquatic ecosystems with animals such as starfish, anemones and mussels.

Rebecca Kordas, lead author of the study at the University of British Columbia (UBC), said: “The herbivores created space for other plants and animals to move in and we saw much more diversity and variety in these ecosystems. We want variety because we found it helps protect the ecosystem when you add a stressor like heat."

The scientists were studying life in the intertidal zone, the area of the shore between the low and high tide. During the course of a day, plants and animals cope with huge variations in temperatures, sometimes as much as 25°C. The researchers discovered that limpets enabled these aquatic communities to cope with these temperature increases.

Kordas said: “These creatures are already living at their physiological limits, so a two-degree change - a conservative prediction of the warming expected over the next 80 years or so - can make a big difference. When heat waves come through British Columbia and the Pacific Northwest, we see mass mortality of numerous intertidal species. When limpets were part of the community, the effects of warming were less harsh.”

The research was published in Science Advances.