Effects of predator hunting mode on grassland ecosystem function

Area of Science:

• Ecology
• Ecosystem Dynamics
• Predator-Prey Interactions

Background:

• Predator hunting mode and prey antipredator behavior interplay to control prey populations.
• The influence of this interplay on ecosystem function remains largely uncertain.
• Grasshopper species are dominant herbivores controlling plant composition and ecosystem functioning.

Purpose of the Study:

• To investigate how predator hunting mode influences ecosystem function.
• To determine the effects of different predator hunting strategies on grassland ecosystems.
• To understand the role of prey responses in mediating these effects.

Main Methods:

• A 3-year experiment was conducted using grassland mesocosms.
• The study compared the effects of actively hunting spiders versus sit-and-wait ambush spiders.
• Measurements included plant species diversity, aboveground net primary production, and nitrogen mineralization rate.

Main Results:

• Actively hunting spiders reduced plant species diversity.
• Actively hunting spiders enhanced aboveground net primary production and nitrogen mineralization rate.
• Sit-and-wait ambush spiders exhibited opposite effects on these ecosystem parameters.

Conclusions:

• Predator hunting mode is a key functional trait influencing top-down ecosystem control.
• Different predator hunting strategies lead to distinct ecosystem functions via prey responses.
• Understanding predator behavior is crucial for predicting ecosystem responses to predation.