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Yucatán, Underground Rivers, Cénotes and Global Groundwater

Much of the world’s freshwater flows underground in limestone labyrinths called karst systems. The Yucatan in Mexico boasts one of the world’s largest, most impressive karst systems yet its health is in jeopardy as coastal development skyrockets along the Riviera Maya. Rising populations combined with climate change are leading to worldwide water shortages as global precipitation patterns shift and frozen water reservoirs melt away.

Beddows, P. A. (2003). An Introduction to the Yucatán Peninsula hydrogeology: A world-class example of a coastal carbonate density stratified aquifer. Cavern Guide Training Program, Asociación de Prestadores de Servícios Acuáticos (Riviera Maya Association of Dive & Watersports Operators – APSA), 45–54. www.karstscience.com/publications/beddows%202003%20intro%20yucatan%20hydrogeology.pdf Off-site Link

Bohannon, J. (2006, August). Not a drop to drink. ScienceNOW, 5.
http://sciencenow.sciencemag.org/cgi/content/citation/2006/821/5 Off-site Link

Roach, J. (2007). World’s Longest underground River Discovered in Mexico, Divers Say. National Geographic News. http://news.nationalgeographic.com/news/2007/03/070305-cave-river.html Off-site Link

Science and Technology for Sustainability Program. (2007). Sustainable management of Groundwater in Mexico: Proceedings of a Workshop (Series: Strengthening Science-Based Decision Making in Developing Countries. The National Academies Press.http://books.nap.edu/openbook.php?record_id=11875&page=52 Off-site Link

Striped Bass

A strange, flesh-eating bacteria had been consuming the flesh of one of America’s prized sport fish—the striped bass. For more information see:

Blankenship, K. (2004). Mycobacteriosis infection rate in Bay’s striped bass increasing. Bay Journal. http://www.bayjournal.com/article.cfm?article=1252 Off-site Link

Jiang, H., Pollock, K. H., Brownie, C., Hoenig, J. M., Latour, R. L., Wells, B.K. and Hightower, J. E. (2007). Tag return models allowing for harvest and catch and release: evidence of environmental and management impacts on striped bass fishing and natural mortality rates. National American Journal of Fisheries Management, 27: 387–396.

Rhodes, M. W., Kator, H., Kotob, S., van Berkum, P., Kaattari, I., Vogelbein, W. K., Quinn, F., Floyd, M. M., Butler, W. R. and Ottinger, C. A. (2003). Mycobacterium shottsii sp. nov., a slowly growing species isolated from Chesapeake Bay striped bass (Morone saxatilis). International Journal of the Society of Environmental Microbiology, 53: 421–424.

Russell, D. (2006). Striper Wars: An American Fish Story. Island Press.

Dead Zones and Nitrogen Overloading

As more and more fertilizers stream off our lawns and agricultural lands, the more nitrogen makes it into our coastal waters. Such an oversupply of nutrients leads to algal blooms that suck oxygen out of the water. As these algae decay they create areas called dead zones. For more information on how too much of a good thing is affecting life in the ocean see:

Bricker, S., Longstaff, B., Dennison, W., Jones, A., Boicourt, K., Wicks, C. and Woerner, J. (2007). Effects of Nutrient Enrichment In the Nation’s Estuaries: A Decade of Change. NOAA Coastal Ocean Program Decision Analysis Series No. 26. National Centers for Coastal Ocean Science, Silver Spring, MD. http://ccma.nos.noaa.gov/publications/eutroupdate/ Off-site Link

Diaz, R. J. and Solow, A. (1999). Ecological and economic consequences of hypoxia. Topic 2. Gulf of Mexico Hypoxia Assessment. NOAA Coastal Ocean Program Decision Analysis Series. NOAA, COP, Silver Springs, MD. Published on the www at: www.nos.noaa.gov/Products/pubs_hypox.html#Topic2 Off-site Link

Howarth, R., Anderson, D., Cloern, J., Elfring, C., Hopkinson, C., Lapointe, B., Malone, T., Marcus, N., McGlathery, K., Sharpley A. and Walker, D. (2000). Nutrient Pollution of Coastal Rivers, Bays and Seas. Issues in Ecology, 7:1–15. www.esa.org/science_resources/issues/FileEnglish/issue7.pdf Off-site Link

Albatross Tracking and Plastic Ingestion

Albatross forage far and wide to feed their chicks. In the Northern Hemisphere, one prime foraging location happens to coincide with the world’s largest dumping ground—the “Garbage Patch” in the north Pacific. For more information on how marine plastic debris affects albatross chicks and other seabirds, see:

Auman, H. J., Ludwig, J. P., Giesy J. P., and Colborn, T. (1995). Plastic Ingestion by Laysan Albatross Chicks on Sand Island, Midway Atoll, in 1994 and 1995. Albatross Biology and Conservation. Robinson, G. and Gales, R. (Ed.). Surrey Beatty & Sons, Chipping Norton.

Hyrenbach, K. D., Keiper, C., Allen, S. G., Ainley, D. G., and Anderson, D. J. (2006). Use of marine sanctuaries by far-ranging predators: commuting flights to the California Current System by breeding Hawaiian albatrosses. Fisheries Oceanography, 15(2): 95–103.

Nevins, H., Hyrenbach, D., Keiper, C., Stock, J., Hester, M. and Harvey, J. (2005). Seabirds as indicators of plastic pollution in the North Pacific. Paper presented at Plastic Debris Rivers to the Sea Conference, 2005. www.oikonos.org/papers/Nevins_etal_2005.pdf Off-site Link

Safina, C. (2007). Wings of the Albatross. National Geographic Magazine. Retrieved from
http://ngm.nationalgeographic.com/2007/12/albatross/safina-text/1 Off-site Link

Marine Debris, Plastic and the Garbage Patch

The vast majority of the plastics that we have produced since the 1950s are all still around, and many have ended up in a great swirling patch of the Pacific Ocean known as the “Garbage Patch.” In some places, plastic outweighs the plankton. For more on our  contributions to marine plastic debris see:

Derraik, J. G.B. (2002). The Pollution of the marine environment by plastic debris: a review. Marine Pollution Bulletin, 44: 842–852.

Moore, C. (2003). Trashed: Across the Pacific Ocean, plastics, plastics, everywhere. Natural History, 112(9): 46–51. http://www.mindfully.org/Plastic/Ocean/Moore-Trashed-PacificNov03.htm Off-site Link

Moore, C.J., Moore, S. L., Leecaster, M. K., and Weisberg, S. B. (2001). A comparison of plastic and plankton in the North Pacific central gyre. Marine Pollution Bulletin, 42(12): 1297–1300.

Chemical Pollution, Plastic Leachates and Bisphenol A

An increasing number of animals are being discovered with genetic and developmental maladies suggestive of impacts from synthetic chemicals known as endocrine disruptors. To find the latest scientific findings relating to the impact of endocrine disruptors like bisphenol A and other plastic derivatives on the developmental systems of animals, consult:

Environmental Health News http://EnvironmentalHealthNews.org Off-site Link

Environmental Working Group www.EWG.org. Off-site Link

Crain, D.A., Eriksen, M. Iguchi, T., Jobling, S., Laufer, H., LeBlanc, G.A., Guillette, L.J. (2007) An ecological assessment of biosphenol A: Evidence from comparative biology, Reproductive Toxicology 24: 225–239.

Gibson, R. L. (2007). Toxic Baby Bottles, Scientific study finds leaching chemicals in clear plastic baby bottles. Environment California Research and Policy Center www.environmentcalifornia.org/uploads/Ve/AQ/VeAQsr6MMu4xA3-2ibnr_g/Toxic-Baby-Bottles.pdf Off-site Link

Swan, S. H. Guillette, L. J. Jr., Myers, J. P. and vom Saal, F. S. (2007). Endocrine disruptors: epidemiological studies of reproductive effects in humans. In Encyclopedia of Ecology. Jorgensen, S.E. and Fath, B. (Eds.). Elsevier.

vom Saal, F. S., Guillette, L. J. Jr., Myers, J. P. and Swan, S. H., (2007). Endocrine disruptors: Effects in wildlife and laboratory animals. In Encyclopedia of Ecology. Jorgensen, S.E. and Fath, B. (Eds.). Elsevier. www.elsevier.com/wps/find/bookdescription.cws_home/706223/description#toc Off-site Link

Calafat, A. M., Kuklenyik, Z., Reidy, J. A., Caudill, S. P., Ekong, J. and Needham, L. L. (2005). Urinary Concentrations of Bisphenol A and 4-Nonylphenol in a Human Reference Population. Environmental Health Perspectives, 113: 391–395. Off-site Link

Coral reefs and climate change

Climate change is affecting coral reefs and the ocean in a multitude of ways. Sea surface temperatures have risen 1˚ Celsius in many tropical areas over the past 100 years, and are currently increasing at 1 to 2˚ Celsius per century. Increased carbon dioxide in the atmosphere is altering ocean chemistry, lowering the pH and potentially making it more difficult for some corals to secrete their calcium carbonate skeletons. Recent studies have shown that calcification rates can drop as much as 25 to 45 percent of normal rates by the end of this century if carbon emissions continue at present levels. For more information on how carbon dioxide is affecting the ocean, see:

Bruno, J. F. and Selig, E. (2007). Regional decline of coral cover in the Indo-Pacific: Timing, extent, and subregional comparisons. PLoS ONE, 2(8): e711. doi:10.1371/journal.pone.0000711. http://www.plosone.org/article/fetchArticle.action?articleURI=info:doi/10.1371/journal.pone.0000711; and http://www.sciencedaily.com/releases/2007/08/070808082051.htm Off-site Link

Enríquez, S., Méndez, E. R., Iglesias-Prieto, R. (2005). Multiple scattering on coral skeletons enhances light absorption by symbiotic algae. Limnology and Oceanography, 50: 1025–1032. http://www.aslo.org/lo/toc/vol_50/issue_4/1025.pdf Off-site Link

Hoegh-Guldberg, O., Mumby, P. J., Hooten, A. J., Steneck, R. S. Greenfield, P., Gomez, E. Harvell, C. D., Sale, P. F., Edwards, A. J., Caldeira, K., Knowlton, N., Eakin, C. M.,  Iglesias-Prieto, R., Muthiga, N., Bradbury, R. H., Dubi, A. and Hatziolos, M. E. (2007). Coral reefs under rapid climate change and ocean acidification, Science, 318 (5857): 1737–1742. www.sciencemag.org/cgi/content/abstract/318/5857/1737 Off-site Link

Sabine, C. L., Feely, R. A., Gruber, N., Key, R. M., Lee, K., Bullister, J. L., Wanninkhof, R., Wong, C. S., Wallace, D. W. R., Tilbrook, B., Millero, F. J., Peng, T., Kozyr, A. R., Ono, T. and Rios, A. F. (2004). The oceanic sink for anthropogenic CO2. Science, 305 (5682): 367–371. www.sciencemag.org/cgi/content/abstract/305/5682/367 and www.sciencedaily.com/releases/2004/07/040719092807.htm Off-site Link

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