<P> The Smithsonian Institution Gulf of Mexico holdings are expected to provide an important baseline of understanding for future scientific studies on the impact of the Deepwater Horizon oil spill . In Congressional testimony, Dr. Jonathan Coddington, Associate Director of Research and Collections at the Smithsonian's National Museum of Natural History, provides a detailed overview of the Gulf collections and their sources which Museum staff have made available on an online map . The samples were collected for years by the former Minerals Management Service (renamed the Bureau of Ocean Energy Management, Regulation and Enforcement) to help predict the potential impacts of future oil / gas explorations . Since 1979, the specimens have been deposited in the national collections of the National Museum of Natural History . </P> <P> The major environmental threats to the Gulf are agricultural runoff and oil drilling . </P> <P> There are frequent "red tide" algae blooms that kill fish and marine mammals and cause respiratory problems in humans and some domestic animals when the blooms reach close to shore . This has especially been plaguing the southwest and southern Florida coast, from the Florida Keys to north of Pasco County, Florida . </P> <P> The Gulf contains a hypoxic dead zone that runs east - west along the Texas - Louisiana coastline . In July 2008, researchers reported that between 1985 and 2008, the area roughly doubled in size and now stretches from near Galveston, Texas, to near Venice, Louisiana . It is now about 8,000 square miles (21,000 km), nearly the record . Poor agricultural practices in the northern portion of the Gulf of Mexico have led to a tremendous increase of nitrogen and phosphorus in neighboring marine ecosystems, which has resulted in algae blooms and a lack of available oxygen . Occurrences of masculinization and estrogen suppression were observed as a result . An October 2007 study of the Atlantic croaker found a disproportioned sex ratio of 61% males to 39% females in hypoxic Gulf sites . This was compared with a 52% to 48% male - female ratio found in reference sites, showing an impairment of reproductive output for fish populations inhabiting hypoxic coastal zones . </P>

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