title: Relationships between blood mercury levels, reproduction, and return rate in a small seabird.
abstract: Mercury (Hg) is a ubiquitous heavy metal that occurs naturally in the environment, but its levels have been supplemented for decades by a variety of human activities. Mercury can have serious deleterious effects on a variety of organisms, with top predators being particularly susceptible because methylmercury bioaccumulates and biomagnifies in food webs. Among birds, seabirds can have especially high levels of Hg contamination and Leach's storm-petrels (Oceanodroma leucorhoa), in particular, have amongst the highest known levels. Several populations of Leach's storm-petrels have declined recently in the Northwest Atlantic. The causes of these declines remain uncertain, but the toxic effects of Hg could be a potential factor in this decline. Here, we tested for relationships between adult blood total Hg (THg) concentration and several offspring development parameters, and adult return rate of Leach's storm-petrels breeding on Bon Portage Island (43° 28' N, 65° 44' W), Nova Scotia, Canada, between 2011 and 2015 (blood samples n = 20, 36, 6, 15, and 13 for each year, respectively). Overall, THg levels were elevated (0.78 ± 0.43 μg/g wet wt.) compared to other species of seabirds in this region, and varied significantly among years. However, we found no associations between THg levels and reproductive parameters or adult return rate. Our results indicate that levels of mercury observed in Leach's storm-petrel blood, although elevated, appear not to adversely affect their offspring development or adult return rate on Bon Portage Island.
authors.affiliation: Acadia University, Wolfville, NS, B4P 2R6, Canada. ipollet@yahoo.com.|Department of Biology, Dalhousie University, Halifax, NS, B3H 4R2, Canada. ipollet@yahoo.com.
authors.forename: Ingrid L
authors.initials: IL
authors.lastname: Pollet
authors.affiliation: Department of Biology, Dalhousie University, Halifax, NS, B3H 4R2, Canada.
authors.forename: Marty L
authors.initials: ML
authors.lastname: Leonard
authors.affiliation: Acadia University, Wolfville, NS, B4P 2R6, Canada.
authors.forename: Nelson J
authors.initials: NJ
authors.lastname: O'Driscoll
authors.affiliation: Environment and Climate Change Canada, Mount Pearl, NL, A1N 4T3, Canada.
authors.forename: Neil M
authors.initials: NM
authors.lastname: Burgess
authors.affiliation: Acadia University, Wolfville, NS, B4P 2R6, Canada.
authors.forename: Dave
authors.initials: D
authors.lastname: Shutler
mesh_terms: D000818:Animals; D001717:Birds / Q000097:blood / Q000502:physiology*; D002170:Canada; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000097:blood*; D008628:Mercury / Q000097:blood*; D012098:Reproduction / Q000187:drug effects*
chemical_list: D004785:Environmental Pollutants; D008628:Mercury
keywords: Leach’s storm-petrel; Mercury; Oceanodroma leucorhoa; Reproduction