Wing membrane and fur samples as reliable biological matrices to measure bioaccumulation of metals and metalloids in bats

Non-invasive sampling of bats reflects their potential as ecological indicators of heavy metal and trace metal contamination due to open cast diamond mining, northern Limpopo Province, South Africa

“…However, toxic thresholds of heavy metals and trace elements is also lacking for shrews. In the available literature, reported element concentrations range from means, to geometric means and medians and thus without the raw data it is not always easily comparable across studies (for example; Hickey et al 2001, Mina et al 2019 and the current study). Comparative data for the 23 elements investigated in our study is scant and limited to a handful of studies that will be discussed below to place our ndings into a global context.…”

“…Heavy metal pollution has been shown to affect bat ecology, genetics, physiology and behaviour. Effects of element pollution include but are not limited to changes relating to bat diversity, alteration of relative abundances, population structure changes, negative impacts on ight activity, disruption of plasma glucocorticoids, central nervous system alterations (causing a general lack of coordination, loss of movement, tremors, paralysis), damage to internal organs (renal inclusion bodies), hemochromatosis ("iron overload"), immunosuppression and mortality (Zocche et al 2010, Zukal et al 2015, Mina et al 2019).…”

“…Bats may be directly exposed to elements through drinking from contaminated water sources or through the accumulation of elements in prey items that breed in polluted waterbodies (Pikula et al 2010, Mansour et al 2016, Mina et al 2019. Bats are also indirectly exposed to pollutants through human activities that may change the physical habitat and alter availability and quality of resources (food and water) (Zocche et al 2010, Gall et al 2015.…”

“…Persistent environmental pollutants are an underrated threat to bats and the manner in which contaminants transfer, bio-magnify through trophic levels and accumulate within an organism (in tissues and organs) is fairly complex (Clarke et al 1986, Flache et al 2018, Mina et al 2019). Different bat species may show speci c trace element concentrations in their tissues and organs associated with variations in exposure within different foraging habitats, dietary guilds and physiological regulation of elements (Karouna-Renier et al 2014, Zukal et al 2015, Flache et al 2015, Hernout et al 2016b, Flache et al 2018, Moreno-Brush et al 2018, Carrasco-Rueda et al 2020, de Souza et al 2020).…”

“…Bats are good potential bioindicators for ecosystem health due to their small size, high mobility, high metabolic rates and associated high prey intake of between 40-100% of their body weight each night, global distribution and coexistence with humans thus increasing their exposure to a range of contaminants (Hickey et al 2001, Jones et al 2009, Russo and Jones 2015, Zukal et al 2015. Bat species of particular interest are those that feed on emerging insects such as Trichoptera which have an aquatic larval stage, typically live in sediment, accumulate metals, and thus provide a pathway for contaminants to pass from aquatic to terrestrial ecosystems (Zukal et al 2015, Mina et al 2019. Being the second highest species-rich mammalian order in the world representing approximately 20% of global mammal diversity, bats form a large component of global biodiversity and deliver key services to both ecosystems and humans (pest control, pollination, seed dispersal and forest regeneration) (Jones et al 2009, Kasso and Balakrishnan 2013, Bayat et al 2014, Riccucci and Lanza 2014, Taylor et al 2018.…”