Selected mineral and heavy metal concentrations in blood and tissues of vultures in different regions of South Africa

Abstract

Concentrations of eight essential elements (Ca, Co, Cr, Cu, Fe, Mn, Ni and Zn) and three toxic metals (Al, Pb and Sr) were measured in various tissue samples from African whitebacked (Pseudogyps africanus), Cape griffon (Gyps coprotheres) and Lappetfaced (Torgos tracheliotos) vultures in different regions of South Africa. Blood samples from live African whitebacked vultures were taken from nestlings from two breeding populations, adults from a wildlife reserve and immature birds held in captivity. With the exception of Sr and Mn, concentrations of the majority of metals differed between two or more of the sampling localities and between captive and wild individuals. Birds from Moholoholo had the highest overall blood metal concentrations, while concentrations in birds from Dronfield were the lowest, as can be expected for nestlings and adults respectively. Fatty tissues and bones had the highest values of metal accumulation, especially Sr, and this is congruent with results from previous studies. It was concluded that most concentrations compared well with those reported for other avian species, but concentrations of Cr, Ni and Pb in the dead vultures were generally above values characteristic of heavy metal poisoning. The values reported for each of two wild populations of P. africanus nestlings and adults, and for two other vulture species could serve as base-line data for future comparative studies.

Tissue distribution and correlations of heavy metals in wild birds from Southern Turkey: an ecologically important region on the west Palearctic migration route

“…Lee et al (2012) reported similar liver Fe concentrations (313-339 mg kg -1 w.w.) in waterfowl. Lower (Kaliniska et al 2006;Komosa et al 2012;Lee et al 2012) and higher (Van Wyk et al 2001;Naccari et al 2009) Mn concentrations have been reported for various bird species. Zn is a essential trace element for the activity of many enzymes in the body, but too much of it might cause an additional source of stress in birds who are already under stress (Perez-Lopez et al 2008).…”

“…Due to high a nity (Cd, Cr, Cu, and Pb in feathers, nails, horns, and hooves), biotransformation (Cd in the liver), and excretion (Cd in the kidney), the accumulation of metals is higher in some tissues and organs referred to as (Mukhtar et al, 2020;Tekeli et al, 2021). Hence feathers (Zolfaghari et al, 2007;Nighat et al, 2013;Grúz et., al, 2018;Squadrone et al, 2018;Mukhtar et al, 2020), liver (Kenntner et., al, 2007;Pérez-López et., al, 2008;Komosa et al, 2012;Salamat et al, 2014;Mukhtar et al, 2020), kidney (Kenntner et., al, 2007;Naccari et al 2009;Mukhtar et al, 2020), muscle (van Wyk et al, 2001;Kalisińska et al, 2006;Naccari et al, 2009;Salamat et. al., 2014) and heart (van Wyk et al, 2001;Mukhtar et al, 2020) are the most commonly examined tissues and organs in studies of environmental pollution-related metal accumulation in wild birds.…”

Trace Element Bioaccumulation in Stone Curlew (Burhinus oedicnemus, Linnaeus, 1758): A Case Study from Sicily (Italy)

“…Many studies about metal bioaccumulation have focused on birds [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32], showing their relevance as biological indicators of pollution. Birds are suitable bioindicators of metal pollution due to (1) their diverse ecology, which allows to show the effects of trace elements on multiple levels of the ecosystem;…”

“…In previous studies illustrating the effects of metals in birds, the effects of certain pollutants on birds across different habitat and ecological systems were analyzed [18][19][20][21][23][24][25][26][27][28][29][30][31][32]34]. For non-essential toxic trace elements, toxic thresholds have been investigated.…”

“…Many studies about metal bioaccumulation have focused on birds [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 ], showing their relevance as biological indicators of pollution. Birds are suitable bioindicators of metal pollution due to (1) their diverse ecology, which allows to show the effects of trace elements on multiple levels of the ecosystem; (2) their ability to bioaccumulate metals in their feathers, blood and other tissues; (3) their ubiquity and worldwide repartition; and (4) their sensibility to a wide range of pollutants, by showing adverse effects after various level of exposure: for instance, impairment of reproduction and growth, endocrine and nervous disorders, genotoxicity, and physiological and behavioral abnormalities affecting survival [ 33 ].…”