Microplastic contamination in terrestrial ecosystems: A study using barn owl (Tyto alba) pellets.

Area of Science:

• Environmental Science
• Ecotoxicology
• Wildlife Biology

Background:

• Microplastics (MPs) are a growing environmental concern, with extensive research in aquatic systems but limited understanding of terrestrial contamination.
• Soils are potential major reservoirs for MPs, necessitating effective monitoring strategies for these ecosystems.

Purpose of the Study:

• To evaluate the efficacy of analyzing barn owl (Tyto alba) pellets as a non-invasive method for assessing microplastic contamination in terrestrial environments.
• To identify the types and prevalence of MPs in agricultural soils via barn owl predation patterns.

Main Methods:

• Collected 60 barn owl pellets from three distinct agricultural areas (20 per site).
• Analyzed pellets for microplastic content using micro-Fourier Transform Infrared Spectroscopy (μ-FTIR).
• Assessed barn owl diet composition to correlate prey with potential MP exposure.

Main Results:

• Confirmed 34 microplastics in 33% of analyzed pellets, with 1-5 MPs per pellet.
• Microfibers constituted the majority (88.2%) of detected MPs, with polyethylene terephthalate, polyacrylonitrile, and polyamide being the most common polymers.
• One site showed significantly lower MP contamination compared to the other two.

Conclusions:

• Barn owl pellet analysis is a viable and cost-effective tool for monitoring terrestrial microplastic pollution.
• Higher MP levels in certain sites correlated with barn owl diets rich in synanthropic rodents, suggesting habitat degradation and MP exposure.
• The strictly herbivorous Savi's pine vole appears to be a prey item with lower MP contamination risk.