Description

Mason Neck National Wildlife Refuge supports the largest great blue heron Ardea herodias rookery in the State of Virginia. The presence of bioaccumulative compounds such as polychlorinated biphenyls and DDT in fish collected from the Potomac River and tidal tributaries along the Refuge led to this study. The objective was to determine if there were any indications of pollutantinduced eggshell thinning or evidence of biochemical exposure to contaminants. We examined eggshell thickness and biomarkers of contaminant exposure in livers of embryos collected from the refuge and Coaches Island, a reference location in Chesapeake Bay. There was no evidence of eggshell thinning. Cytochrome P450 activity, measured as ethoxyresorufinOdealkylase EROD and benzyloxyresorufinOdealkylase BROD, was not significantly different in embryos from the two colonies. Biochemical indicators of oxidative stress can be reflected as changes in levels of reduced thiols, oxidized glutathione, and thiobarbituric reactive substances TBARS. Although there were significant differences in the levels of reduced glutathione GSH and total thiol TSH activities in the embryo livers, there were no statistically significant differences in TBARS, proteinbound sulthydryls PBSH, oxidized glutathione GSSG and the ratio of GSSG to GSH. In fact, the concentrations of GSH and TSH were higher in the Mason Neck birds relative to Coaches Island. Under conditions of increased oxidative stress at least one or more of the following would be expected: decreased concentrations of reduced thiols GSH and TSH, increased GSSG, and increased TBARS. In conclusion, we did not detect eggshell thinning or find evidence of a biochemical response to contaminant exposure in the Mason Neck great blue herons.

General Information

• This data is described at

  http://catalog.data.gov/dataset/investigation-of-eggshell-thickness-and-biochemical-indicators-of-contaminant-exposure-in- Do you think this data is incorrect? Let us know

• This data is published by

  US Fish and Wildlife Service, Department of the Interior Do you think this data is incorrect? Let us know

Legal Information

• The rights statement is at

  http://catalog.data.gov/dataset/investigation-of-eggshell-thickness-and-biochemical-indicators-of-contaminant-exposure-in- Do you think this data is incorrect? Let us know

• Outside the US, this data is available under

  Creative Commons CCZero Do you think this data is incorrect? Let us know

• There are

  yes, and the rights are all held by the same person or organisation Do you think this data is incorrect? Let us know

• The content is available under

  Creative Commons CCZero Do you think this data is incorrect? Let us know

• The rights statement includes data about

  its data licence Do you think this data is incorrect? Let us know

• This data contains

  no data about individuals Do you think this data is incorrect? Let us know

Practical Information

• The data appears in this collection

  http://catalog.data.gov/organization/fws-gov Do you think this data is incorrect? Let us know

• The accuracy or relevance of this data will

  go out of date but it is timestamped Do you think this data is incorrect? Let us know

• The data is

  backed up offsite Do you think this data is incorrect? Let us know

Technical Information

• This data is published at

  http://ecos.fws.gov/ServCatFiles/reference/holding/21740?accessType=DOWNLOAD Do you think this data is incorrect? Let us know

• The format of this data is

  a standard open format Do you think this data is incorrect? Let us know

Social Information

• The documentation includes machine-readable data for

  title Do you think this data is incorrect? Let us know

• The documentation includes machine-readable data for

  description Do you think this data is incorrect? Let us know

• The documentation includes machine-readable data for

  identifier Do you think this data is incorrect? Let us know

• The documentation includes machine-readable data for

  landing page Do you think this data is incorrect? Let us know

• The documentation includes machine-readable data for

  publisher Do you think this data is incorrect? Let us know

• The documentation includes machine-readable data for

  keyword(s) or tag(s) Do you think this data is incorrect? Let us know

• The documentation includes machine-readable data for

  distribution(s) Do you think this data is incorrect? Let us know

• The documentation includes machine-readable data for

  release date Do you think this data is incorrect? Let us know

• The documentation includes machine-readable data for

  modification date Do you think this data is incorrect? Let us know

• The documentation includes machine-readable data for

  temporal coverage Do you think this data is incorrect? Let us know

• The documentation about each distribution includes machine-readable data for

  release date Do you think this data is incorrect? Let us know

• The documentation about each distribution includes machine-readable data for

  a URL to access the data Do you think this data is incorrect? Let us know

• The documentation about each distribution includes machine-readable data for

  a URL to download the dataset Do you think this data is incorrect? Let us know

• The documentation about each distribution includes machine-readable data for

  type of download media Do you think this data is incorrect? Let us know

• Find out how to contact someone about this data at

  http://catalog.data.gov/dataset/investigation-of-eggshell-thickness-and-biochemical-indicators-of-contaminant-exposure-in- Do you think this data is incorrect? Let us know

• Find out how to suggest improvements to publication at

  http://www.data.gov/issue/?media_url=http://catalog.data.gov/dataset/investigation-of-eggshell-thickness-and-biochemical-indicators-of-contaminant-exposure-in- Do you think this data is incorrect? Let us know