Ethan VanValkenburg

All Publications

• Sodium-enriched nectar shapes plant-pollinator interactions in a subalpine meadow ECOLOGY AND EVOLUTION Vanvalkenburg, E., Goncalves Souza, T., Sanders, N. J., Caradonna, P. 2024; 14 (7): e70026

  Abstract

  Many plants have evolved nutrient rewards to attract pollinators to flowers, but most research has focused on the sugar content of floral nectar resources. Concentrations of sodium in floral nectar (a micronutrient in low concentrations in nectar) can vary substantially both among and within co-occurring species. It is hypothesized that sodium concentrations in floral nectar might play an important and underappreciated role in plant-pollinator interactions, especially because many animals, including pollinators, are sodium limited in nature. Yet, the consequences of variation in sodium concentrations in floral nectar remain largely unexplored. Here, we investigate whether enriching floral nectar with sodium influences the composition, diversity, and frequency of plant-pollinator interactions. We experimentally enriched sodium concentrations in four plant species in a subalpine meadow in Colorado, USA. We found that flowers with sodium-enriched nectar received more visits from a greater diversity of pollinators throughout the season. Different pollinator species foraged more frequently on flowers enriched with sodium and showed evidence of other changes to foraging behavior, including greater dietary evenness. These findings are consistent with the "salty nectar hypothesis," providing evidence for the importance of sodium limitation in pollinators and suggesting that even small nectar constituents can shape plant-pollinator interactions.

  View details for DOI 10.1002/ece3.70026

  View details for Web of Science ID 001268304300001

  View details for PubMedID 39015879

  View details for PubMedCentralID PMC11251754