Habitat-Dependent Provisioning Patterns Are Modulated by Weather Conditions in a Rapidly Declining Farmland Raptor

Area of Science:

• Avian ecology
• Conservation biology
• Farmland biodiversity

Background:

• Agricultural intensification reduces high-quality habitats, threatening European farmland biodiversity.
• Little Owl (Athene noctua) populations have declined due to factors like food limitation during breeding.
• The impact of agricultural habitat quality on parental provisioning and weather effects on this is poorly understood.

Purpose of the Study:

• To investigate how agricultural habitat quality affects parental food provisioning in Little Owls across Europe.
• To determine how weather conditions modulate provisioning patterns in relation to habitat quality.
• To analyze the interacting effects of habitat quality and weather on nestling diet.

Main Methods:

• Nestbox cameras monitored parental food provisioning in Little Owls across four European countries (2002-2022).
• Data collected from 40 nests and 58 broods, analyzing provisioning rate, biomass, and nestling diet.
• Investigated effects of habitat quality, temperature, and wind speed on provisioning patterns.

Main Results:

• Provisioning rate and biomass increased with high-quality habitat area, showing quadratic relationships with temperature and decreasing with wind speed.
• High-quality habitats buffered against adverse weather, enabling greater biomass provisioning at low temperatures and higher rates during high winds.
• Prey composition varied significantly between habitat types under poor weather, with Little Owls accessing more insects and voles in high-quality areas.

Conclusions:

• Enhancing high-quality habitats and heterogeneity within territories is crucial for Little Owl conservation.
• Conservation efforts should focus on mitigating food limitation, especially under adverse weather conditions.
• Maintaining and improving farmland habitat quality supports avian predators and overall biodiversity.