title: Interactive effects of climate change with nutrients, mercury, and freshwater acidification on key taxa in the North Atlantic Landscape Conservation Cooperative region.
abstract: The North Atlantic Landscape Conservation Cooperative LCC (NA LCC) is a public-private partnership that provides information to support conservation decisions that may be affected by global climate change (GCC) and other threats. The NA LCC region extends from southeast Virginia to the Canadian Maritime Provinces. Within this region, the US National Climate Assessment documented increases in air temperature, total precipitation, frequency of heavy precipitation events, and rising sea level, and predicted more drastic changes. Here, we synthesize literature on the effects of GCC interacting with selected contaminant, nutrient, and environmental processes to adversely affect natural resources within this region. Using a case study approach, we focused on 3 stressors with sufficient NA LCC region-specific information for an informed discussion. We describe GCC interactions with a contaminant (Hg) and 2 complex environmental phenomena-freshwater acidification and eutrophication. We also prepared taxa case studies on GCC- and GCC-contaminant/nutrient/process effects on amphibians and freshwater mussels. Several avian species of high conservation concern have blood Hg concentrations that have been associated with reduced nesting success. Freshwater acidification has adversely affected terrestrial and aquatic ecosystems in the Adirondacks and other areas of the region that are slowly recovering due to decreased emissions of N and sulfur oxides. Eutrophication in many estuaries within the region is projected to increase from greater storm runoff and less denitrification in riparian wetlands. Estuarine hypoxia may be exacerbated by increased stratification. Elevated water temperature favors algal species that produce harmful algal blooms (HABs). In several of the region's estuaries, HABs have been associated with bird die-offs. In the NA LCC region, amphibian populations appear to be declining. Some species may be adversely affected by GCC through higher temperatures and more frequent droughts. GCC may affect freshwater mussel populations via altered stream temperatures and increased sediment loading during heavy storms. Freshwater mussels are sensitive to un-ionized ammonia that more toxic at higher temperatures. We recommend studying the interactive effects of GCC on generation and bioavailability of methylmercury and how GCC-driven shifts in bird species distributions will affect avian exposure to methylmercury. Research is needed on how decreases in acid deposition concurrent with GCC will alter the structure and function of sensitive watersheds and surface waters. Studies are needed to determine how GCC will affect HABs and avian disease, and how more severe and extensive hypoxia will affect fish and shellfish populations. Regarding amphibians, we suggest research on 1) thermal tolerance and moisture requirements of species of concern, 2) effects of multiple stressors (temperature, desiccation, contaminants, nutrients), and 3) approaches to mitigate impacts of increased temperature and seasonal drought. We recommend studies to assess which mussel species and populations are vulnerable and which are resilient to rising stream temperatures, hydrological shifts, and ionic pollutants, all of which are influenced by GCC.
authors.affiliation: US Fish and Wildlife Service, Chesapeake Bay Field Office, Annapolis, Maryland.
authors.forename: Alfred E
authors.initials: AE
authors.lastname: Pinkney
authors.affiliation: Department of Civil and Environmental Engineering, Syracuse University, Syracuse, New York, USA.
authors.forename: Charles T
authors.initials: CT
authors.lastname: Driscoll
authors.affiliation: Biodiversity Research Institute, Gorham, Maine, USA.
authors.forename: David C
authors.initials: DC
authors.lastname: Evers
authors.affiliation: Columbia Environmental Research Center, US Geological Survey, Columbia, Missouri.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Hooper
authors.affiliation: US Fish and Wildlife Service, Northeast Regional Office, Hadley, Massachusetts.
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Horan
authors.affiliation: US Fish and Wildlife Service, Virginia Tech University, Blacksburg, Virginia.
authors.forename: Jess W
authors.initials: JW
authors.lastname: Jones
authors.affiliation: Patuxent Wildlife Research Center, US Geological Survey, Beltsville, Maryland.
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Lazarus
authors.affiliation: Department of Biological Sciences, Old Dominion University, Norfolk, Virginia, USA.
authors.forename: Harold G
authors.initials: HG
authors.lastname: Marshall
authors.affiliation: US Fish and Wildlife Service, Northeast Regional Office, Hadley, Massachusetts.
authors.forename: Andrew
authors.initials: A
authors.lastname: Milliken
authors.affiliation: Patuxent Wildlife Research Center, US Geological Survey, Beltsville, Maryland.
authors.forename: Barnett A
authors.initials: BA
authors.lastname: Rattner
authors.affiliation: US Fish and Wildlife Service, Division of Refuges, Arlington, Virginia.
authors.forename: John
authors.initials: J
authors.lastname: Schmerfeld
authors.affiliation: Department of Zoology, Southern Illinois University, Carbondale, Illinois, USA.
authors.forename: Donald W
authors.initials: DW
authors.lastname: Sparling
mesh_terms: D000818:Animals; D059001:Aquatic Organisms / Q000145:classification / Q000254:growth & development; D001267:Atlantic Ocean; D044822:Biodiversity; D057231:Climate Change; D003247:Conservation of Natural Resources; D017753:Ecosystem; D004784:Environmental Monitoring; D005068:Eutrophication; D005618:Fresh Water / Q000737:chemistry; D008628:Mercury / Q000032:analysis; D014876:Water Pollution / Q000706:statistics & numerical data*
chemical_list: D008628:Mercury
keywords: Algal blooms; Contaminants; Global climate change; Hypoxia; Nutrients