Noninvasively Collected Fecal Samples as Indicators of Multiple Pesticide Exposure in Wild Birds

Abstract

Pesticide use poses a potential hazard to wild birds that use agricultural farmland as their foraging habitat. Whereas most current pesticide studies have found residues in liver samples and single active substances, noninvasive sampling methods and data on a wide variety of agrochemicals are needed to determine pesticide exposure of living wild birds for postregistration monitoring. We collected feces during autumn migration of Eurasian skylarks (Alauda arvensis), a species that commonly forages in winter cereal crops. Birds were kept in paper bags until we measured their body condition, individually marked and released them. We analyzed the feces dropped in paper bags for the presence of 80 pesticides including rodenticides and degradation products. Nine active substances from fungicides and herbicides commonly used in grain and maize fields were detected individually, or in combination, in 25% of the samples. We found no significant differences in body condition between exposed and unexposed birds, but Eurasian skylarks without pesticide residues had a better body condtion score on average than birds with pesticide residues. Pesticide determination in noninvasively collected fecal samples allows a refined risk analysis, which takes pesticides used in the habitats of birds into account. It allows the search for the sources of pesticide contamination, but also enables research into potential deleterious effects on the fitness of farmland birds.

Spatial variation of rodenticides and emerging contaminants in blood of raptor nestlings from Germany

“…Spiroxamine residues were furthermore detected in wild boar ( Sus scrofa ) and roe deer ( Capreolus capreolus ) muscles from Poland (Kaczyński et al 2021 ), which are both common prey species of HAALs in Germany but not for the species analyzed in Rial-Berriel et al ( 2020 ), where spiroxamine was not detected (LOQ: 0.1 ng mL −1 ). Terbuthylazine was one of the most frequently detected PPPs in insect traps from nature conservation areas in Germany (Brühl et al 2021 ) and was previously detected in dermal swap samples from amphibians (Schenke et al 2020 ) as well as in fecal samples (terbuthylazine‐2‐hydroxy) of Eurasian skylarks ( Alauda arvensis ) from Germany (Esther et al 2022 ). Furthermore, terbuthylazine is formulated together with bromoxynil in one of the previously approved PPP products in Germany (Zeagran® ultimate), which indicates similarities in exposure pathways for both substances.…”

Preliminary Evidence of Anticoagulant Rodenticide Exposure in American Kestrels (Falco sparverius) in the Western United States

“…In future studies, doing a clotting time assay of birds from which blood is drawn could provide additional evidence and context of exposure. We also recommend exploring the development of sampling and analytical techniques to test for ARs in kestrel excreta (Esther et al 2022), which can easily be collected from nest boxes post-fledging and from captured wild birds. The potential to passively and noninvasively sample wild populations via excreta sampling after juveniles fledge from a nest box represents a potentially valuable technique that could provide insights into exposure throughout the full nesting season.…”

The neonicotinoid, imidacloprid, disrupt the chicken sperm quality through calcium efflux

“…These notable instances exemplify the grave danger posed by wildlife poisoning to biodiversity ( Mateo-Tomas et al, 2020 ). The application of pesticides presents a possible threat to wild avian species that utilize agricultural fields as their primary feeding grounds ( Esther et. al., 2022 ).…”