Pollinator effectiveness is affected by intraindividual behavioral variation

Area of Science:

• Ecology
• Evolutionary Biology
• Behavioral Ecology

Background:

• Plant-pollinator mutualisms are crucial for ecosystem function.
• Pollinator foraging behavior varies greatly, but its impact on pollen transfer is understudied.

Purpose of the Study:

• To investigate how foraging behavior of bumble bees (Bombus impatiens) affects pollen removal and deposition.
• To examine the influence of bee body size and pollen placement on pollen movement.
• To understand how these factors interact with plant species characteristics.

Main Methods:

• Artificial flowers were used to control pollen donation and bee foraging behavior.
• Captive bumble bees were used to transfer pollen to three recipient plant species.
• Pollen removal, deposition, and bee body size were quantified.

Main Results:

• Bee body size primarily influenced pollen removal, while foraging behavior primarily affected pollen deposition.
• Pollen deposition varied significantly with plant species, particularly those with smaller stigmas.
• Heterospecific pollen interfered with conspecific pollen deposition on certain plant species.

Conclusions:

• Intraindividual variation in pollinator foraging behavior is a key driver of pollinator quality.
• Interactions between bee behavior, pollen load, and floral traits shape plant fitness.
• Understanding these dynamics is vital for plant reproductive success and evolution.