Total mercury (Hg) and stable isotopes of nitrogen and carbon were determined in the muscle tissue of 50 species of fishes and invertebrates collected at two sites along the Florida reef tract from April 2012 -December 2013. The objective was to test the hypothesis that high biodiversity in coral reefs leading to complex food webs with increased lateral links reduces biomagnification. However, Hg levels ranged as high 6.84 mg/kg. Interestingly, it was not highest in great barracuda (Sphyraena barracuda), considered the top predatory fish, but instead in small porkfish (±95% confidence interval) to 0.201 ±0.07. These TMS were also within the ranges of slopes reported for food webs in other ecosystems; thus, biomagnification of Hg in muscle tissue was not reduced in the system.

No abstract