A novel record of a stranding of a Cuvier's beaked whale, Ziphius cavirostris in the Río de la Plata, Argentina; with preliminary results on heavy metals

CÁCERES-SAEZ, I.; GARIBOLDI, C.; TOSSENBERGER, V.; HEVIA, M.; PANEBIANCO, V.; FORLENZA, C.; GONZALEZ, L.; PERALTA, D.; VILCHES, F.; LUCERO, S.; REYES, M. V.; GASPARROU, C.; CAPPOZZO, H. L.

Lima

Congreso; XII Congreso de la Sociedad Latinoamericana de Especialistas en Mamíferos Acuáticos RT 18; 2018

Sociedad Latinomericana de Especialistas en Mamíferos Acuáticos (SOLAMAC)

Ziphiidae or beaked whales, are all classified as ?Data Deficient? by the IUCN. Out of the 21st members constituting the family, Cuvier?s beaked whale (Ziphius cavirostris) has the most cosmopolitan distribution. It has been widely recorded from tropical to warm temperate, and occasionally even in sub-polar and polar waters. A major problem when studying this species in the wild is its wide-ranging oceanic habitats. In the South Atlantic Ocean its presence has been reported mainly from strandings and less frequently identified at sea. As a result, stranded specimens offer good opportunities to gather biological and ecological information on this species. On 22nd October, 2016, the presence of a stranded specimen was reported by officials on the coast of the Río de la Plata estuary, Vicente López, Buenos Aires province, Argentina (BA, Arg., 34°31'05''S; 58°28'11''W). The stranding was attended by biologists and veterinarian students coordinated by OPDS, BA, Arg. The animal body length was 5.12 m. The carcass was in advanced decomposition (type 4) and the necropsy was performed according to standard protocols. Tissue samples of liver, kidney, muscle, lung, spleen and skin were excised in order to develop toxicological analysis. The skeleton named as MACN-Ma.27287 is stored at the Museo Argentino de Ciencias Naturales Bernardino Rivadavia, BA, Arg. Here we presented the concentrations of Pb, Cd, Ni, Cr, Zn and Cu determined by inductive coupling plasma mass spectrometry (ICP-MS). The range of metal levels among tissues were for: Cr, 46 - 109 μg/L; Cu, 34 - 280 μg/L; Zn, 104 ? 13,250 μg/L and Cd, 3.5 ? 2,073 μg/L. Lead and Ni in all tissues were below the detection limit of the method. To our knowledge, very few studies have been published worldwide providing metal concentrations in this species however; the mean concentrations of these elements varied within values reported for other marine mammals in the South Atlantic Ocean. Long-term databases of pollutants in stranded mammals along with pathological examination are essential to assess their health condition, and delineate strategies for conservation of their populations.