Population declines and heavy metal exposure of Swinhoe's Storm Petrels (Oceanodroma monorhis) breeding on the southwest coast of Korea

Marine debris ingestion by adults and fledglings of Swinhoe's storm petrels in the Republic of Korea

Procellariiformes are highly vulnerable to marine plastic pollution due to their species-specific life histories. In particular, storm petrels are known to be one of the most vulnerable species with respect to plastic ingestion. In this study, we examined the plastic ingestion by adults and fledglings of Swinhoe's storm petrels on Chilbal Island, one of the largest breeding colonies for this species. During 2013 and 2014, we collected adult and fledgling carcasses and analyzed their stomach contents. The results showed that both adults and juveniles were consuming mostly plastics. Most of the collected Swhinhoe's storm petrels were consuming microplastic, with juveniles consuming a higher average amount of plastic than adults. The type of plastic ingested was more threadlike in adults and fragments in juveniles. In conclusion, the characteristics of ingested plastics differed between adults and juveniles, suggesting that analyzing individual age may be important for monitoring plastic ingestion in the future.

Tissue distribution and correlations of heavy metals in wild birds from Southern Turkey: an ecologically important region on the west Palearctic migration route

Even if some are essential for biological functions, the accumulation of heavy metals above tolerable physiological limits is potentially toxic to also wild animals. The present study aimed to investigate concentrations of environmentally relevant heavy metals (As, Cd, Cu, Fe, Hg, Mn, Pb, and Zn) in feathers, muscle, heart, kidney, and liver tissues of wild birds (golden eagle [Aquila chrysaetos], sparrowhawk [Accipiter nisus], and white stork [Ciconia ciconia]) from Hatay province, southern Turkey. The metal concentrations of tissues were determined by a validated ICP-OES analysis method after microwave digestion. The concentration differences of metals in species/tissues and the correlations between essential/non-essential metals were determined by statistical analysis. According to the results, Fe (326.87±3.60 mg kg^-1) had the highest, and Hg (0.09±0.00 mg kg^-1) had the lowest mean concentration in all tissues. Compared to the literature; Cu, Hg, Pb, and Zn concentrations were lower; Cd, Fe, and Mn concentrations were higher. The correlations between As and all essentials; Cd and Cu, Fe; Hg and Cu, Fe, Zn; Pb and all essentials were significantly positive. In the conclusion, while essential Cu, Fe, and Zn are below the threshold value and do not pose a risk, Mn is close to the threshold value. Therefore, periodically monitoring the pollutant concentrations in bioindicators is a key necessity for the early determination of biomagnification trends and prevention of potential toxic stress on wildlife ecology.