Doi: https://doi.org/10.13157/arla.72.2.2025.ra1
Authors: Chabier GONZÁLEZ, Ignacio De BLAS and Lluís LUJÁN
E-mail: chabiergo@gmail.com
Published: Volume 72.2, July 2025. Pages 161-175.
Language: English
Keywords: impaction, landbirds, landfills, plastic, plasticosis, rubber and silicone
Summary:
The aim was to study the presence and importance of solid pollutants found in the digestive system of White Storks Ciconia ciconia in Aragón, north-eastern Spain. Necropsies of a total of 1,550 storks were carried out. A total of 1,045 presented digestive contents. Solid contents found in the oesophagus, proventriculus and ventriculus were identified by their nature and shape and classified into twelve categories, according to material origins. The volume of these materials was measured and classified as Low, medium and high, relative to the maximum volume of a normal white stork pellet. Solid pollutants were found in 342 birds out of 1,045 examined digestive contents (32.7%). In 142 of these cases (41.5%), two or more categories of solid pollutants were observed in the same animal. Rubber bands were the most frequently found contaminant, detected in 200 (19.1%) ventriculi. Silicone was found in 66 (6.3%) ventriculi. All other materials were much less frequent. Impaction linked to very large quantities of rubber bands (> 200ml) was detected in five cases. Digestive obstruction only represented 0.9% of cases but 6.3% of the examined digestive contents showed a high volume of solid pollutants. The occurrence of such solid pollutants in the digestive did not differ with sex or age. The presence of these materials in the digestive system of white storks was associated with foraging at rubbish dumps and possibly was also related to massive intake of the rubber bands that are sometimes abandoned in cropfields. This is a significant environmental problem affecting White Storks that requires better rubbish dump management, improved agricultural practices and greater environmental awareness by the general population.
Supplementary Material:
Downloadable 1
