No remarkable effect of blood mercury on corticosterone levels in Black-tailed Gulls

Abstract

Mercury (Hg) contamination impacts the corticosterone stress response via the hypothalamic-pituitary-adrenal axis in some bird species. Any alteration of the normal function of the stress response can have adverse effects on physiological functions, health and survival. However, the effects of Hg on the stress response vary between bird species. In this study we investigated the relationship between Hg concentrations and corticosterone levels in the blood of Black-tailed Gull Larus crassirostris to understand the effect of Hg contamination on the species' corticosterone stress response. We found no effect of Hg on corticosterone levels in adult Black-tailed Gull. One possible reason for this may be related to the lack of correlation between Hg accumulation in the blood and Hg accumulation in the adrenal glands, the main organ that regulates corticosterone levels.