Ecosystems represent units within which complex ecological interactions amongst living organisms and the non-living environmental component that support life occur. Amongst many others, these natural ecosystems include forests, grasslands and deserts (Kunz et al.
, 2011). The ecological interactions of living organisms in ecosystems inadvertently produce benefits that are important to the sustenance of life (Kunz et al., 2011; Millennium Ecosystem Assessment, 2003).
Ideally, well-functioning ecosystems give rise to natural processes that facilitate primary productivity, disperse seed, drive decompose matter, provide food, fuels, medicinal products, water, fibers, prevent floods, cultural, spiritual and recreational benefits that are essential for sustaining life (Ghanem & Voigt, 2012; Millennium Ecosystem Assessment, 2003). However, the increasing alterations to ecosystems caused by human activities relating but not limited to urbanization, mining, agriculture and the effects of pollution threaten not only to damage but also carries the possibility to make these ecosystems become dysfunctional and unproductive.
Since their evolution 50 million years ago, bats have become highly adaptable animals with well-developed life history traits and have continued to inhabit the earth, exploiting a wide variety of these ecosystems (Ducummon, 2000; Kunz et al., 2011). They are highly diverse and exhibit complex social, physiological and feeding habits that contribute positively to the well-being of ecosystems rendering services that are considered both ecologically and economically beneficial to man and the environment (Kasso & Balakrishnan, 2013).
For instance, bats produce large amounts of guano in caves, which has a long history of being used as a natural fertilizer for agricultural crops as a rich source of nitrogen and phosphorus, potassium as well as trace elements that are crucial for stimulating growth, enhancing root development and strengthening stems of plants (Bharambe, 2016; Kasso & Balakrishnan, 2013; Shetty & Sreepada, 2013). Bat guano has been used to fertilize soils in the production of vegetables, fruit trees, herbs, flowers and crops (Bharambe, 2016). Bracken cave dwelling bats of Texas have over many years produced large quantities of guano which has been harvested and used as commercial fertilizer, even to the extent of being sold at prices of up to 12 dollars per kilogram (Ghanem & Voigt, 2012; Kasso & Balakrishnan, 2013). As a result, this does not only provide monetary benefits but also stimulates and supports the growth of important commercial cash crops such as cotton and maize (Ducummon, 2000; Ghanem & Voigt, 2012; Kasso & Balakrishnan, 2013). Further, some bacteria extracted from bat guano have been used in detoxification of industrial waste, improvement of some detergents, production of pesticides, herbicides and even some antibiotics (Bharambe, 2016; Ducummon, 2000; Ghanem & Voigt, 2012). Even more, saltpeter as an important ingredient in the production of gun powder has historically been extracted from bat guano (Ducummon, 2000). While the potential economic value of bat guano still remains to be fully quantified, it is clear that its use as natural fertilizer and extracts thereof being used in a variety of commercial products represent positive economic benefits. Equally, bat guano supports a good number of cave ecosystems as a primary source of energy for cave dwelling micro-organisms including bacteria, fungi, nematodes and arthropods (Emerson & Roark, 2007; Shetty & Sreepada, 2013).
Bats ability for powered flight allows them to explore and adapt to new environments and facilitate the exploitation of variable habitats. Their mobility enables them to pass nutrients and fertilize soils in different environments by dropping nutrient rich feces during foraging and migratory activities, thereby contributing to the recycling and redistribution of nutrients (Emerson & Roark, 2007).
Although not much emphasis is placed on the role of bats as prey items for other animals, reports indicate that they constitute some proportion of the diets of birds, reptiles and some carnivorous mammals (Mikula et al., 2016; Vargas, Landaeta, & Simonetti, 2002; Esb?rard & Vrcibradic, 2007; Kasso & Balakrishnan, 2013). While owls account for the largest threat of predation on bats, snakes and birds of prey like hawks and falcons as well as small carnivores such as raccoons and feral cats have also been reported to feed on bats (Esb?rard & Vrcibradic, 2007; Kasso & Balakrishnan, 2013; Mikula et al., 2016; Motta JR & Taddei, 1992). In addition, even some larger species of bats such as the spectral bat (Vampyrum spectrum) is known to feed on other bats of smaller sizes (Khan, 2015). As a result of their fairly predictable patterns of day roosting and emergence from roost sites, some of these predators take advantage and opportunistically invade roosts or ambush bats during emergence from roosts in order to feed themselves (Kasso & Balakrishnan, 2013). Although, predation on bats is still considered incidental and does not constitute a major threat to bat populations, it nevertheless still represent an important ecological feature of the food chain dynamics that help maintain functionality of ecosystems (Mikula et al., 2016).