Naslov
Mercury in tissues of brown bears in Croatia: age, sex and seasonal differences

Autori
Lazarus, Maja ; Jurasović, Jasna ; Huber, Djuro ; Reljić, Slaven ; Zec, Davor

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
20th International Conference on Bear Research and Management : Program and Abstract / - Ottawa : International Association for Bear Research & Management, 2011, 176-176

Skup
International Conference on Bear Research and Management (20 ; 2011)

Mjesto i datum
Ottawa, Kanada, 17.07.2011. - 23.07.2011

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
brown bears; tissue mercury

Sažetak
Continuous monitoring of mercury (Hg) levels as toxic metal in wild animals is important because of its ability to accumulate in biological tissues thereby impairing animal’s health. Also, such monitoring gives us valuable information about Hg levels in the surrounding environment. Without notable anthropogenic Hg source in studied regions of Croatia, measured levels in largely herbivorous bears would reflect plant Hg levels transferred from soil (natural sources) or Hg transported via the atmosphere (remote anthropogenic sources). In contrast to large number of reports about contaminants in largely carnivorous polar bears, Hg levels in European brown bear were studied only sporadically, lacking any information about Croatian population. In this study, Hg levels were measured in muscle, liver and kidney cortex of 90 brown bears (Ursus arctos) hunted during spring and fall 2009 and spring 2010 according to The Brown Bear Management Plan for Croatia. Age-, sex- and season-related differences were examined. Distribution of Hg across tissues was as follows (median ; range): muscle (0.002 ; 0.00008-0.018 μg/g), < liver (0.034 ; 0.0001-0.198 μg/g), < kidney (0.238 ; 0.016-1.20 μg/g wet weight). Tissue levels correlated between themselves (Spearman R= 0.5-0.7, p<0.001). Whereas age had no influence on Hg in any bear tissue, sex and season (in males) showed such trend. Females had higher Hg in all three tissues compared to males (p<0.05) but showed no differences between spring and fall Hg content. Males shot in fall had higher Hg in liver (p<0.001) and kidney (p<0.001) then the ones shot in spring. As prevalent route of Hg intake in bear is ingestion, seasonal cycles in food availability is reflected on differences in food consumption. Factors causing sex-differences in Hg levels could be hormones, reproductive state, and size variations. Found Hg levels are in the same range as previously reported for brown bear population from western Carpathians.

Izvorni jezik
Engleski

Znanstvena područja
Biologija, Veterinarska medicina

POVEZANOST RADA