Wildlife hair as bioindicators of metal exposure

A recent study explains the implications it may have in future research that will try to fight against metal pollution

by Lorenzo Ciotti
Wildlife hair as bioindicators of metal exposure

Wildlife hair as bioindicators of metal exposure is a study published on the Biological trace element research, which explains the implications it may have in future research that will try to fight against metal pollution.

The researchers explained: "Animal hair is a useful biomonitoring tool for assessing the occurrence of trace elements in ecosystems. Essential (chromium, copper, iron, manganese, nickel, and zinc) and nonessential (aluminum, arsenic, cadmium, mercury, lead, palladium, platinum, rubidium, tin, and vanadium) elements were investigated in hair of badger (Meles meles), wild boar (Sus scrofa), marmot (Marmota marmota), wolf (Canis lupus), fox (Vulpes vulpes) and deer ( Cervus elaphus) from Northwestern Italy.

Badger was found to be the highest bioaccumulator of metals, while wolf, fox and deer recorded the lowest values. Essential elements contribute in higher degree to the sum of metals for all species except for wild boar. Results have shown that animals with omnivorous diet such as badger, marmot and wild boar have metal content higher than carnivores (wolf and fox) and herbivores (deer) and could represent an effective sentinel of environmental exposure to metals." In mammals, hair replaces the scales of fish, reptiles and amphibians.

However, if these have a role in thermoregulation, the hair of mammals instead have a fundamental role in insulation, i.e. maintaining the temperature, the regulation of which is the task of the circulatory system. That is, the hairs serve to defend themselves from temperatures that are too high and above all from those below the norm; the case of the bear or the marmot is evident, for example, which have a thick fur to defend themselves from the excessive winter cold.

The pelage of most mammals with thick fur generally consists of hair of two different types. The former, generally longer, robust, relatively stiff and tapering at the tip, form the so-called jar, which is often the only part of the fur that is externally visible and is generally the same in summer and winter.

This layer instead varies according to the seasons, as it is almost absent in summer and highly developed in winter, to the point of sometimes going beyond the jar, causing a chromatic change of the animal according to the seasons, as in the case of the chamois and of the roe deer.

In some artiodactyls, such as sheep, goats, alpacas and camels, the fluff is so thick and developed that it forms a compact layer in which it is impossible to separate one hair from the other and can be used by man for the production of fabrics; in this case it takes the name of wool.