Observing the Color Preferences of Native Pollinators

Introduction 

Pollinators play a crucial role in maintaining biodiversity and supporting the survival of numerous plant species. This diverse group includes bees, butterflies, moths, birds, bats, flies and beetles, each contributing to ecosystem health. Bees, for example, are responsible for pollinating approximately 75% of global crops, underscoring their importance in agricultural productivity.¹ Declines in pollinator populations can have far-reaching consequences for ecosystems and plant diversity.² Despite their significance, pollinators face threats such as habitat loss, pesticide use, climate change, invasive species and disease.³ The decline of pollinators presents a serious challenge, underscoring the need to understand their survival requirements.⁴ One key factor is their color preferences, which can offer valuable insights into enhancing plant-pollinator interactions.  

Research has shown that bees are attracted to saturated colors like blues and purples but struggle to perceive reds due to their lack of red receptors.² Instead, their color receptors are primarily ultraviolet (UV).² While studies on bee color preferences have provided valuable insights, there is a need to expand research to investigate the color and UV preferences of other native pollinators, addressing a critical gap in our understanding. 

Methods 

Data was collected at Sleeping Giant State Park located in Hamden, CT. White Shasta daisies were colored with both UV and regular pollinator safe paint: Blue, pink, purple, yellow and white (control). 

The Shasta daisies were placed at Sleeping Giant and were left for 30 minutes to allow them to acclimate to the environment, before observations began. Pollinators were observed and recorded based on the number and type of pollinators, the time spent on a flower and its color. 

To incorporate ultraviolet (UV) elements into the original methods, UV paints were tested to determine their UV reflectance values. Various UV paints were evaluated to identify those that would produce the most distinct results and work within this research. 

The data was quantified and presented in a graph, which illustrates the comparison between non-UV and UV paints, highlighting the differences in color reflectance. 

References

¹ Ollerton, J., Winfree, R., & Tarrant, S. (2011). How many flowering plants are pollinated by animals? Oikos, 120(3), 321-326.
² Papiorek, S., Rohde, K., and Lunau, K. (2013). Bees’ subtle colour preferences: how bees respond to small changes in pigment concentration. Naturwissen schaften 100, 633–643. doi: 10.1007/s00114-013-1060-3
³ Potts, S. G., Biesmeijer, J. C., Kremen, C., Neumann, P., Schweiger, O., & Kunin, W. E. (2010). Global pollinator declines: trends, impacts and drivers. Trends in Ecology & Evolution, 25(6),
345-353.
⁴ Shrestha, M., Dyer, A. G., and Burd, M. (2013). Evaluating the spectral discrimination the evolution of flower colours. Commun. Integr. Biol. 6:e24000. doi: 10.4161/cib.24000
⁵ Winfree, R., Aguilar, R., Vázquez, D. P., LeBuhn, G., & Aizen, M. A. (2018). A meta-analysis of bees' responses to anthropogenic disturbance. Ecology Letters, 21(7), 962-970.
⁶Barghini, Alessandro & de Medeiros, Bruno. (2012). UV Radiation as an Attractor for Insects. LEUKOS The Journal of the Illuminating Engineering Society of North America. 9. 47-56. 10.1582/LEUKOS.2012.09.01.003.