Predation pressure on sentinel prey does not necessarily diminish with advancing urbanization

Area of Science:

• Ecology
• Urban Ecology
• Wildlife Biology

Background:

• Urbanization significantly alters natural habitats, impacting ecological interactions like predation.
• Understanding changes in predation pressure is crucial for assessing urbanization's ecological consequences.

Purpose of the Study:

• To investigate seasonal predation pressure in urban versus rural forests.
• To determine the impact of urbanization on predator-prey dynamics.

Main Methods:

• Utilized the sentinel approach with model caterpillars (plasticine) over a full season (April-October).
• Collected data in rural and urban forest fragments near Debrecen, Hungary.
• Analyzed attack marks to quantify predation pressure from arthropods, birds, and mammals.

Main Results:

• High overall predation pressure was observed, with up to 36% of models showing attacks.
• Predation pressure was significantly higher in summer than in spring or autumn.
• Surprisingly, urban habitats exhibited higher attack rates than rural habitats, contradicting the hypothesis of reduced predation in urban areas.

Conclusions:

• Urbanization may not decrease but can increase predation pressure in forest fragments.
• Higher urban predation could be due to factors like predator hunger or reduced vigilance in urban environments.
• Findings challenge general assumptions about predator-prey interactions in urbanized landscapes.