Release depends upon the bat’s ability to fly, take food and water on the wing and find cover in daylight.
The bat should be in good body condition before release.
Several days of good weather are preferred ahead of the release date to ensure that the bat is being released in optimal conditions.
Individual bats from known roosts (that are ready for release) can be released from a gloved hand as the colony emerges, if the roost can still be located. Currently there is no research to indicate how reliable this method is and it is important that bats released like this have developed the necessary skills to survive.
Young bats of larger species will learn to fly in a large flight cage, but will not have the space to hunt on the wing. They can be soft released from a suitable familiar bat box with support feeding. Advice should be sought from experienced carers.
Research by Ancilotti et al 2012 (see Further information, support and references) on juvenile bats indicates that social links are established during the nursery stages.
Rearing young bats from the same colony together or putting together groups of juveniles where their original roosts are not known may have a beneficial effect (but consider health and safety, see Health and safety>Isolation).
Such groups can be released from a familiar bat box (one they can easily fly back into) either close to the original roost (where known), or in an area of suitable habitat, in the general area of finding (also see Kelly et al 2008, 2012).
Soft release with supported feeding may be possible depending on circumstances, and advice should be sought.
In situations where an individual is deemed unsuitable for release a decision should be made on whether to euthanise the individual or keep in permanent captivity (and use for educational purposes). See Ethics. Euthanasia should be considered at every stage in the decision making process.