The stress of being contaminated? Adrenocortical function and reproduction in relation to persistent organic pollutants in female black legged kittiwakes

Abstract

High levels of environmental pollutants such as persistent organic pollutants (POPs) including PCB and DDT have been found in the Arctic and many of those pollutants may impair reproduction through endocrine disruption. Nevertheless, their effects on stress hormones remain poorly understood, especially in free-ranging birds. Corticosterone, the principal glucocorticoid in birds, can indirectly impair reproduction. The aim of the present study was to examine the relationships between POPs and reproduction through their potential consequences on different reproductive traits (breeding decision, egg-laying date, breeding success) and corticosterone secretion (baseline and stress-induced levels). We addressed those questions in an Arctic population of female black-legged kittiwakes during the pre-breeding stage and measured several legacy POPs (PCBs and pesticides: HCB, p,p'-DDE, CHL) in whole blood. POP levels were not related to breeding decision neither to breeding success, whereas females with high levels of pesticides laid their eggs earlier in the season. We found a negative relationship between POP levels and body condition index in non-breeding females. Black-legged kittiwakes with higher levels of PCB showed stronger adrenocortical response when subjected to a capture-handling stress protocol.We suggest that PCBs may disrupt corticosterone secretion whereas the positive relationship between pesticides and egglaying date could either originate from a direct effect of pesticides or may be related to other confounding factors such as age or individual's quality. Although no direct negative reproduction output of POPs were found in this study, it is possible that the most contaminated individuals would be more sensitive to environmental stress and would be less able to maintain parental investment than less polluted individuals.

A comparison of two methods for the assessment of stress axis activity in wild fish in relation to wastewater effluent exposure

“…Gagnon et al, 2006) and whole effluents (Ings et al, 2011b) but some do report amplification of the cortisol response to stressors in fish (e.g. Gesto et al, 2008;Lerner et al, 2007;Melnyk-Lamont et al, 2014) and in other taxa (Franceschini et al, 2008;Tartu et al, 2014). Investigation of the activity of key genes responsible for coordinating HPI axis activity and for metabolising cortisol will be informative in this context.…”

Survival rate and breeding outputs in a high Arctic seabird exposed to legacy persistent organic pollutants and mercury

“…This positive relationship between HCB and breeding performance appears surprising, as contaminants are believed to induce deleterious effects on reproductive traits. Previous studies have pointed out that female kittiwakes and gulls with higher levels of organochlorine pesticides laid their eggs earlier in the season (Bustnes et al, 2008;Tartu et al, 2014). As laying early is related to high breeding success (Lack, 1968), this could explain the positive relationship between HCB and the probability of successfully raising two chicks.…”

“…The Norwegian Arctic is recognized as a final sink for organic and metallic pollutants, which are transported by atmospheric and oceanic currents and by large rivers (Gabrielsen and Henriksen, 2001). Previous studies in this population of Svalbard kittiwakes have reported deleterious effects of Hg and POPs on endocrine mechanisms (Nordstad et al, 2012;Tartu et al, 2013Tartu et al, , 2014. The estimated number of breeding pairs in the Svalbard archipelago is 270 000 in 215 colonies (Strøm, 2006).…”

Water deprivation increases maternal corticosterone levels and enhances offspring growth in the snake Vipera aspis

“…Concomitantly with predictable demands of reproductive effort, breeding individuals can also face unpredictable events that further amplify GC secretion (e.g. density, Dantzer et al, 2013; food shortage, Kitaysky et al, 2010; heat stress, Eriksen et al, 2007;predation, Coslovsky and Richner, 2011;Saino et al, 2005; anthropogenic disturbances, Ellenberg et al, 2007;Tartu et al, 2014). In addition, several studies have experimentally demonstrated that an increase in maternal levels of corticosterone (CORT; the main GC in birds, reptiles, and rodents) significantly influenced offspring phenotypes (Belliure et al, 2004;Hayward and Wingfield, 2004;Clobert, 2004, 2005;Meylan et al, 2002;Warner et al, 2009;Zagron and Weinstock, 2006).…”