Sugar responsiveness could determine foraging patterns in yellowjackets

Area of Science:

• Ecology
• Behavioral Ecology
• Sensory Biology

Background:

• Sympatric species often partition resources through various mechanisms.
• Sensory variations can drive niche partitioning, reducing overlap between closely related species.
• Understanding sensory differences is key to explaining coexistence in social wasps.

Purpose of the Study:

• To investigate if sensory responses to carbohydrates differ between two Vespula species in Patagonia.
• To determine if these sensory variations correlate with foraging patterns and resource exploitation.
• To assess the role of sensory niche partitioning in promoting coexistence of invasive wasps.

Main Methods:

• Laboratory experiments measured carbohydrate response thresholds for Vespula germanica and Vespula vulgaris.
• Field studies analyzed sugar concentrations of foraged carbohydrates by both species.
• Correlations were examined between sensory sensitivity, foraging patterns, and colony size.

Main Results:

• Vespula germanica exhibited a higher sucrose response threshold than Vespula vulgaris.
• Vespula germanica foraged significantly higher carbohydrate concentrations (57% >50% w/w) compared to Vespula vulgaris (23% >50% w/w).
• Differences in sucrose sensitivity and foraging patterns correlated positively with colony size.

Conclusions:

• Sensory differences in sugar perception likely reduce niche overlap and competition between Vespula germanica and Vespula vulgaris.
• This sensory niche partitioning allows for coexistence of these closely related invasive social wasp species.
• Sensory mechanisms play a crucial role in mediating species interactions and promoting coexistence.