Avian ecosystem functions are influenced by small mammal ecosystem engineering

Area of Science:

• Ecology
• Behavioral Ecology
• Ecosystem Engineering

Background:

• Birds act as crucial mobile link species influencing pollination, seed dispersal, and predation.
• Avian communities often associate with habitats modified by small mammal ecosystem engineers.
• This study examines bird foraging preferences in relation to degu (Octodon degus) runways.

Purpose of the Study:

• To investigate if birds prefer foraging on degu runways.
• To compare bird foraging effort across varying densities of degu runways.
• To quantify avian foraging's impact on plot-scale functional diversity.

Main Methods:

• Field study in Rinconada de Maipú, central Chile.
• Measured granivory by birds at sites with different runway densities.
• Sampled invertebrate prey richness and abundance to assess potential insectivory.
• Quantified an index of avian foraging functional diversity.

Main Results:

• Birds located food sources faster and consumed more at sites with higher degu runway density.
• These preferred sites exhibited higher invertebrate prey richness but lower abundance.
• Omnivorous and insectivorous birds forage for invertebrates in degu runway-rich areas where granivory occurs.

Conclusions:

• Degu ecosystem engineering significantly influences avian mobile link species behavior.
• Avian foraging behavior, driven by degu activities, correlates with ecosystem functioning at small spatial scales.