PS 41-29 - CANCELLED - Invasive Anemones Buffer Host-Associated Microbiota Against Thermal Stres

Background/Question/Methods

Invasive species are increasingly prevalent, yet strategies for managing introductions are limited by our incomplete understanding of factors driving their successful establishment. Although physiological and reproductive invasive traits are well known, the role of host-associated microbial communities in invasion success are rarely addressed. Mutualist microbiota can provide beneficial services to their host like enhancing disease resistance, improving nutrient acquisition, and facilitating environmental acclimation. For invasive species, being able to acclimate to new environments encourages permanent establishment. This project aims to identify the temperature thresholds under which three species of sea anemone buffer their microbial communities. “Buffering” is the anemone’s ability to guard their microbiota against environmental stress, maintaining community compositions markedly different from the surrounding water. If the ability to maintain a distinct microbial community contributes to host resilience and increases invasion success, the most wide-spread invasive anemone (Diadumene lineata) will buffer its microbial community under the broadest range of temperatures. Anemones were subjected to a temperature gradient from 0°C to 40°C, covering nearly the full range of sea surface temperatures. After a three-day incubation, their bacterial communities were identified using 16S rRNA sequencing to define the temperature range under which each species maintains a stable community composition.

Results/Conclusions

At lower temperatures from 0°C to 20°C, all anemones had a relatively stable bacterial composition. In contrast, at 40°C, all anemone species exhibited 100% mortality and displayed high bacterial diversity and high variation in community composition between individual anemones. Importantly, at 30°C, the most widespread sea anemone D. lineata displayed 0% mortality, while Diadumene leucolena had 70% mortality and Metridium senile had 100% mortality. D.lineata also possessed the least variation in diversity and microbial community composition between individual anemones. This suggests D. lineata may have the highest temperature stress threshold for microbial community buffering, which is vital if beneficial microbiota are contributing to invasion success. Our results establish the role of host-mediated assembly in invasion ecology, supporting the potential for host-microbe relationships to enhance invasion success.