Giant otter (Pteronura brasiliensis) at risk? Total mercury and methylmercury levels in fish and otter scats, Peru
Ambio
1997
Journal Article
26
8
511-514
single-species study ecology animal behavior Pteronura brasiliensis giant otters threatened species aquatic habitats rivers Parque Nacional del Manu Brazil gold mining pollution mercury lutra fish rivers water quality animals mammals carnivores Carnivora Madre de Dios Bibliography
Mercury and methylmercury levels in fish muscle and seats of the giant otter (Pteronura brasiliensis) of Manu National Park, Peru, and in one gold-mining area in the vicinity of its borders were analyzed. In 68% of fish muscles, total mercury levels exceeded the proposed maximum tolerable level of 0.1 mg kg(-1) fresh weight in fish for the European otter (Lutra lutra), and 17.6% exceeded 0.5 mg kg(-1) fresh weight, the most common standard for human consumption. The ratio of methylmercury to total mercury in fish muscle was from 61.3% up to 96.9%, No methylmercury and only traces of inorganic mercury could be detected in the otter seats. No data for tissue concentrations of the giant otter are available at the moment, but as a high percentage of fish levels exceeded the tolerable level, as given for the European otter, a possible risk of mercury intoxication in the giant otter can be postulated, on the basis of mercury intoxication in free-living otters in Europe and North America described in the past.