The post-release fate of hand-reared orphaned bats: survival and habitat selection

Abstract

Although bats are frequently admitted to rescue centres-mainly as orphans-very little information is available on their survival after release. Our study answered the following questions: i) do hand-reared bats survive over a short time; ii) which activities and habitat selection do they exhibit; iii) are bats loyal to the release area; and iv) are they able to join local colonies? We radio-tracked 21 hand-reared Pipistrellus kuhlii over a two-year period released on a site that differed from that where they were rescued. At the study site they were provided with the same bat boxes used in the rehabilitation room. Nineteen bats were confirmed to survive, stay in the area and actively forage over 4-14 days. Fourteen day roosts in buildings (nine of which hosted a local colony) were used by 12 subjects. Bats travelled less than 5 km in total each night; their most frequent activity was night roosting, followed by foraging and commuting. We recorded typical foraging behaviour, including hunting around street lamps at sites exploited by many conspecifics. A comparison of habitats available within individual home ranges with those within the study area showed that urban areas, riparian vegetation and farmland were equally important and preferred to woodland. When the foraging time spent in each habitat was compared with habitat composition within individual home ranges or within the study area, urban sites were preferred for foraging over all other habitats, followed by farmland and woodland and finally riparian vegetation. Overall, we showed that hand-raised orphaned P. kuhlii may readily adapt to environments they are not familiar with, exhibit a high short-term survival and select key resources in the release area, provided appropriate rehabilitation and training techniques are adopted.

An appetite for pests: Synanthropic insectivorous bats exploit cotton pest irruptions and consume various deleterious arthropods

“…Thus, the prey taxa we identified in the diet of P. kuhlii probably reflect its synanthropic tendencies and foraging sites. The high mobility of P. kuhlii (Maxinová, Kipson, Naďo, Hradická, & Uhrin, 2016; Serangeli, Cistrone, Ancillotto, Tomassini, & Russo, 2012) should allow it to forage in a diverse range of foraging grounds within a mixed‐crop agroecosystem while searching for aggregations of arthropods that are most valuable to exploit at a given time. Arthropod pest irruptions probably generate an attraction for aerial hawking bats, particularly those of lucrative orders such as moths (Krauel et al, 2018; McCracken et al, 2012).…”

Veterinary treatment and rehabilitation of indigenous wildlife

“…Pre-release flight training is an essential part of the rehabilitation process in birds and bats (Fajado et al 2000, Holz et al 2006, Kelly et al 2008, Serangeli et al 2012. Flight training has been shown to be most successful where it attempts to mirror natural conditions.…”

Spatial Proximity between Newborns Influences the Development of Social Relationships in Bats

“…Altringham 1996): it proved sufficient to compensate for the slower growth rate observed in captive P. kuhlii and achieve complete young development (Serangeli et al 2012). The time taken in our rearing protocol for weaning in captivity was somewhat longer than that known for wild bats (e.g.…”

“…The time taken in our rearing protocol for weaning in captivity was somewhat longer than that known for wild bats (e.g. Altringham 1996): it proved sufficient to compensate for the slower growth rate observed in captive P. kuhlii and achieve complete young development (Serangeli et al 2012). In this phase, no contact was allowed between bats from different groups; to avoid indirect olfactory contact, different keepers took care of each group.…”