Red Fox Vulpes vulpes (L., 1758) as a Bioindicator of Mercury Contamination in Terrestrial Ecosystems of North-Western Poland

Abstract

In this study, we determined the concentrations of total mercury (Hg) in samples of liver, kidney and skeletal muscle of 27 red foxes Vulpes vulpes (L., 1758) from north-western Poland, and examined the morphometric characteristics of the collected specimens. The analysis also included the relationship between Hg concentration and the fox size, and the suitability of individual organs as bioindicators in indirect evaluation of environmental mercury contamination. Determination of Hg concentration was performed by atomic absorption spectroscopy. In the analysed samples, the Hg concentration was low and the maximum value did not exceed 0.85 mgHg/kg dry weight (dw). There were no significant differences in Hg concentrations in the analysed material between males and females or between immature and adult groups. The median concentrations of Hg in the liver, kidney and skeletal muscle were 0.22, 0.11 and 0.05 mgHg/kg dw, respectively. The correlation coefficients were significant between the concentrations of mercury in the liver, kidney and skeletal muscle (positive) and between the kidney Hg concentration and kidney mass (negative). Taking into account our results and findings of other authors, it may be argued that the red fox exhibits a measurable response to mercury environmental pollution and meets the requirements of a bioindicator.

Mercury bioaccumulation in hair and skin of arctic foxes (Vulpes lagopus) and silver foxes (Vulpes vulpes) in rural and urbanized region

“…This was also demonstrated in the study of Filistowicz et al (2012) who observed significantly higher accumulation of Cr and Cu in hairs, and Cr, Ni, and Zn in skin of V. vulpes compared to V. lagopus. In turn, Kalisinska et al (2012) revealed very different values of Hg content in liver and kidneys of V. vulpes (0.04-0.52 (0.14 on average) in liver, and 0.09-0.84 (0.30 on average) mg/kg DM in kidneys).…”

“…In arctic fox (Vulpes lagopus formerly known as Alopex lagopus) in Canada, mean Hg content observed in liver was 0.14 μg/g wet weight (Hoekstra et al 2003), while in the USA (Alaska) in kidneys it was even 1.59 mg/kg DM (Dehn et al 2006). Other data concerning Hg content in organs and tissues of farm and wild foxes in various regions of the world were reported by Kalisinska et al (2012). There are however only sparse data of this toxic element content in hair coat or raw skin of both fox species.…”

Hair and bone as predictors of tissular mercury concentration in the Western Alaska Red Fox, Vulpes vulpes

“…Kiener and Zaitsev (2010) and Lanocha et al (2014). Mercury concentrations in terrestrial mammals occasionally show a wide intraspecific variability (Duffy et al 2005; Kalisinskia et al 2009, 2012) influenced by natural environmental differences. Mercury concentrations in livers from red foxes, Vulpes vulpes , from the Province of Siena in Italy were shown to differ in relation to sex and age (Corsolini et al 1999).…”

“…It exists in several forms: elemental (metallic mercury), inorganic (mercuric chloride) and organic (methylmercury) compounds (Clarkson and Magos 2006). It is released into the atmosphere and water by volcanic activity, weathering of rocks; and, anthropogenic mercury is through industry emissions from agriculture, manufacturing, and mining (Bilandzic et al 2010; Clarkson 1997; Clarkson and Magos 2006; Kalisinska et al 2012). In ecotoxicological studies, total mercury (THg) is mainly determined as the sum of organic (mostly as methylmercury) and inorganic mercury (Eisler 1987).…”

Variation in fur farm and wild populations of the red fox, Vulpes vulpes (Carnivora: Canidae) — Part I: Morphometry

“…Tryjanowski et al (2009) demonstrated that mean BW of farm foxes in Poland was 7.4 kg for males and 6.1 kg for females, while in wild foxes, these values were 5.4 and 6.6 kg, respectively. In the case of BL, the results of a study by Lorek et al (2001) indicate that the mean BL of farm males and farm females was 72 and 67 cm, respectively, while in wild foxes, the value of this parameter was 65 cm (Kalisińska et al 2012). A closer look at the body size of female and male foxes reveals the elimination of sexual dimorphism in farm foxes.…”