Indirect Effects of Climate Variation on Pollinator Foraging Behavior

Ainsley Jajack
Fri, 17 Apr 2026 10:45:00 PDT

Many species exhibit intraspecific trait variation in response to climactic factors. When those traits mediate species interactions, the outcome of the interaction may change as a result. For example, floral color and size have been demonstrated to change in response to temperature, precipitation, and soil moisture. Additionally, floral color and size are important influences on pollinator foraging behavior, which can in turn directly impact plant reproductive fitness. As western Montana’s climate patterns trend towards increased seasonal highs and fewer frost/freeze days, it is important to understand how floral traits may shift under changing conditions, and how those shifts may impact pollinator behavior. In the North Hills outside of Missoula, MT, there is an endemic plant, Phlox missoulensis, whose flowers exhibit variation in size and color. Observed variance in P. missoulensis floral size and color may be influenced by local temperature and precipitation patterns and may affect pollinator foraging patterns. In spring 2025, we collected data on floral size and color and pollinator visits to P. missoulensis populations on Waterworks Hill and Bluebird Preserve. We examine (1) whether floral color and size are influenced by local temperature, precipitation, and soil moisture and (2) whether floral traits affect pollinator visitation rates. We expect that floral size will increase with increased precipitation and soil moisture, while floral pigmentation will decrease under drier, hotter conditions. We also expect that pollinator visitation will increase with increasing size and pigmentation levels. Our findings will provide important insight into how the pollination of this endemic species may be impacted by a warmer and drier climate.