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The Real Human Impacts on the Corals of Almirante Bay, Panama
Volume 17, Number 16: 16 April 2014

In a study recently published in Environmental Monitoring and Assessment, Seemann et al. (2014) describe how specific anthropogenic impacts - including turbidity, eutrophication and physical impacts - have threatened reef health and biodiversity throughout Panama's Almirante Bay, by linking these impacts to the current condition of the Bay's coral reefs. So what do they have to tell us about what's going on there?

The seven scientists report that "over the last two decades anthropogenic activities within and surrounding Almirante Bay have resulted in increased turbidity within the bay," such that secchi depth values decreased from 9-13 m in 2006-2008 (Collin et al., 2009) to 5-8 m in 2010 and 2011, while "seasonal average chlorophyll a values all over the bay have increased compared to values from 2006 to 2008," with values at Pastores and Casa Blanca nearly doubling (from 0.46-0.49 to 0.78-0.97 g/l), whereas they say that "coral reefs typically do not exceed values of 0.4 g/l," citing Edinger et al. (2000), Cooper et al. (2007) and Sawall et al. (2011).

The seven scientists also report that chlorophyll a has doubled at sites close to the city and port of Almirante due to a greatly increased suspension load, such that "visibility decreased from 9-13 meters down to 4 meters at the bay inlet Boca del Drago, which is strongly exposed to river runoff and dredging for the shipping traffic," while eutrophication and turbidity levels seemed to be the determining factor for the loss of hard coral diversity," which within the bay had declined, "at some sites down to <10% with extremely low diversities." In addition, they say that "serious overfishing was detected in the region by a lack of adult and carnivorous fish species."

Seemann et al. thus conclude their discourse by stating that "a decrease in sediment loads and eutrophication is essential for the protection of coral reefs of the Almirante Bay," and predicting that "if protection efforts are not increased, coral mortality will continue resulting in a loss of biodiverse reef structures, fish sources and the economic value from tourism."

This is the real tragedy of ignoring the real world of coral reefs, while focusing almost solely on the claimed - but unproven - negative impacts of global warming and ocean acidification; for by the time that any significant change in earth's global temperature and its oceans' pH could be brought about by man (which transformation is highly debatable in the first place), there would likely be little, if anything, left of earth's coral reef ecosystems for us to save.

Sherwood, Keith and Craig Idso

Collin, R., D'Croz, L., Gondola, P. and Rosario, J.B.D. 2009. Climate and hydrological factors affecting variation in chlorophyll concentration and water clarity in the Bahia Almirante, Panama. Smithsonian Contributions to the Marine Sciences 38: 324-334.

Cooper, T.F., Uthicke, S., Humphrey, C. and Fabricius, K.E. 2007. Gradients in water column nutrients, sediment parameters, irradiance and coral reef development in the Whitsunday Region, central Great Barrier Reef. Estuarine, Coastal and Shelf Science 74: 458-470.

Edinger, E.N., Limmon, G.V., Jompa, J., Widjatmoko, W., Heikoop, J.M. and Risk, M.J. 2000. Normal coral growth rates on dying reefs: Are coral growth rates good indicators of reef health? Marine Pollution Bulletin 40: 404-425.

Sawall, Y., Teichberg, M., Seemann, J., Litaay, M., Jompa, J. and Richter, C. 2011. Nutritional status and metabolism of the coral Stylophora subseriata along a eutrophication gradient in Spermonde Archipelago (Indonesia). Coral Reefs 30: 841-853.

Seemann, J., Gonzalez, C.T., Carballo-Bolanos, R., Berry, K., Heiss, G.A., Struck, U. and Leinfelder, R.R. 2014. Assessing the ecological effects of human impacts on coral reefs in Bocas del Toro, Panama. Environmental Monitoring and Assessment 186: 1747-1763.