2019-20 Global Change Fellow
Statement of Purpose:
One of the predicted consequences of climate change that may be currently underestimated is the change in distribution and prevalence of parasites that affect humans, livestock, crops and wildlife. These alterations in distribution are mainly triggered by changes in temperature, precipitation and humidity patterns, that allow parasites, pathogens and/or their vectors to spread to new areas outside of their native range, or to areas from where they had been previously eradicated. Hosts in these populations are likely to be susceptible to the parasites, as they lack a history of exposure and coevolution with them. In the same way, changes in environmental conditions, could affect parasite life cycles, causing alterations in their temporal distribution, and forcing us to reevaluate control strategies. Climate-driven changes in the ecology of infectious diseases could have serious impacts on human and ecosystem health, the economy, and conservation. This last threat is especially notorious in honey bees, with parasitic mite, several fungal, bacterial and viral diseases affecting them. However, native, wild pollinators also suffer from a wide range of parasites, and there is an increasing number of reports of parasites from commercial bees spreading in wild bee populations. This makes the current spread of bee parasites a threat not only for biodiversity but also for food security around the world.
Description of Research:
For my doctoral research, I study the intestinal bee parasite Crithidia bombi, which has been linked to the population decline of some bumble bee species. This parasite is transmitted horizontally to a new colony when an infected bee defecates on a flower, and a new bee ingests the Crithidia cells present in the feces. During the time period that the parasite spends outside its host, it is exposed to UV light, desiccation and high temperatures, that can affect its survival and ability to infect a new host. For part of my project, I am interested in exploring the influence that those factors have on the survival and infectivity of C. bombi, and how they interact with floral morphology to determine the final transmission probability. My preliminary data from the summer of 2018 suggest that temperature is an important factor, given that higher temperature results in fecal drops drying up faster, decreasing parasite survival given that C. bombi cells cannot survive once fecal drops dry up. Understanding the effect of environmental factors on the transmission dynamics of this parasite would allow us to better predict how this parasite may respond to different climate change scenarios, and predict areas where an increase (or decrease) in prevalence is expected. Moreover, there is great interest in planting pollinator friendly gardens and using flowering pollinator strips to enhance pollination services; my research may help identify the flowering traits or species that offer the lowest parasite transmission probabilities under various climate change scenarios.
This research aligns with CASC mission by acquiring scientific information relevant for the conservation and management of species that provide the ecosystem services of pollination. It relates to SE CASC Science Priority 2: Improve partner understanding of how species of conservation concern will be affected by changing climate and land use, and with the Secretary of the Interior Priority 1: Creating a conservation stewardship legacy second only to Teddy Roosevelt, more specifically with section a) Utilize science to identify best practices to manage land and water resources and adapt to changes in the environment.
View a video developed by Simon describing his research as a Global Change Fellow: