Assessment of Heavy Metal Accumulation in the Golden Jackal (Canis aureus) as a Possible Bioindicator in an Agricultural Environment in Bulgaria

Abstract

The aim of this study was to evaluate the residues of heavy metals as an indicator of environmental pollution in internal organs of golden jackal (Canis aureus) from an agricultural region in Bulgaria. It was demonstrated that the golden jackal has high potential for specific accumulation of heavy metals, thus implying that this species may serve as a biological indicator of their presence in the agricultural regions, which it inhabits. The concentrations of the targeted elements (mean [mg/kg of dried tissue] ± SD) were respectively: Cu-57.62 ± 10.76; Zn-141.45 ± 11.33; Ni-0.28 ± 0.19; Co-0.46 ± 0.30; Pb-6.88 ± 1.67 and Cd-0.58 ± 0.16 in liver and Cu-17.67 ± 5.01; Zn-58.28 ± 10.81; Ni-0.51 ± 0.4; Co-0.52 ± 0.29; Pb-4.03 ± 1.32 and Cd-1.41 ± 0.22 in kidney samples. The concentrations we found revealed the specific accumulation of these metals in golden jackal and provide values, within which negative effects on the advancement of its populations should not be expected.

Concentrations of cadmium and lead, but not zinc, are higher in red fox tissues than in rodents—pollution gradient study in the Małopolska province (Poland)

“…However, because there were no significant differences in concentrations of these metals between the two rodent species, we can average the EFs for the two species, obtaining + 0.511 for mg/kg log 10 Cd in the kidney and + 0.454 mg/kg for log 10 Pb in the liver. These results are consistent with those reported by Markov et al (2016), who compared the accumulation of trace metals in medium size carnivores, such as the golden jackal ( Canis aureus ) and the red fox, and in the rodent, fat dormouse ( Glis glis ), inhabiting agricultural environment in Bulgaria. They noted significantly higher Zn, Pb, and Cd concentrations in the liver and kidney of the carnivores than in the dormouse.…”

“…They noted significantly higher Zn, Pb, and Cd concentrations in the liver and kidney of the carnivores than in the dormouse. However, the carnivores and the dormouse studied by Markov et al (2016) came from different areas in Bulgaria, without a direct link between the trophic levels. Our Małopolska study is the first to our knowledge to investigate the accumulation of trace metals in the three mammalian species (a medium size carnivore and two rodents species) related directly by trophic relations and coming from the same areas with known concentrations of trace metals in soil.…”

Accumulation of selected metals and concentration of macroelements in liver and kidney tissues of sympatric golden jackal (Canis aureus) and red fox (Vulpes vulpes) in Somogy County, Hungary

“…Our finding concerning the higher level of Pb in fox livers than in fox kidneys appears to be consistent with other results ranging from Spain to Poland and Bulgaria (Pérez-López et al 2015;Binkowski et al 2016;Georgiev et al 2018;Zietara et al 2019) as well as with those noted in tissue samples of jackals from some Bulgarian agricultural areas (Markov et al 2016). This latter result is also consistent with our findings based on the full set of data.…”

“…The higher Pb concentration in liver samples found based on the full set of data is in accordance with the results of Bulgarian agricultural areas (Markov et al 2016), while the lack of organ dependent significant differences in concentrations observed based on paired tests confirm the results of Georgiev et al (2018).…”

“…Depending on the testing method used, differences in accumulations of Al, Ca, Cr, Mg, and Pb in jackal kidneys and livers were inconsistent. Similar studies targeting heavy metal accumulation in both golden jackal liver and kidney samples were performed only in two Bulgarian study sites: (1) in a relatively intensive agricultural region (Markov et al 2016) and (2) at the "Sarnena Sredna gora" mountain (Georgiev et al 2018). Descriptive comparisons instead of statistical analyses were performed at the second location.…”