Page 68 - Zoo Animal Learning and Training

40 3 The Ultimate Benefits of Learning

As with antipredator training, operant
VetBooks.ir feed. Released grey partridges (P. perdix), for conditioning can be used to enhance
example, feed throughout the day rather than
concentrating feeding bouts around dawn
Conditioned taste aversion techniques have
and dusk, as their wild counterparts do appropriate feeding/foraging behaviour.
(Rantanen et al. 2010). This could be a result been used to encourage animals to avoid
of the consistency of food availability in cap- potentially toxic prey (e.g. Cremona et al.
tivity, which leads to captive birds feeding 2017), or undesirable food items (such as
throughout the day or it is possible that the commercial crops), and exposing predators
birds are less efficient at feeding in the wild to live prey pre‐release greatly increases their
and therefore require more time to gather an chances of successful hunting post‐release
adequate amount of energy from their food (e.g. Houser et al. 2011).
(Rantanen et al. 2010).
The ability to catch live prey is often
reported as a reason for failed mammalian 3.3.5 Other Learned Factors
Affecting Reintroduction
carnivore reintroductions (Jule et al. 2008),
but it is likely to be as important in bird and In many studies no one specific behaviour
reptile species destined for reintroduction was cited as the reason for success and/or
too. A study by DeGregorio et al. (2013) dem- failure of a reintroduction attempt, but gen-
onstrated the importance that captivity can eral differences in behaviour expressed by
have on ratsnake foraging behaviour. wild and captive conspecifics as a result of
Ratsnakes (Elaphe obsolete) that had been captivity were reported. For example north-
kept in captivity short term (under 2 weeks) ern water snakes (Nerodia sipedon sipedon)
reacted correctly to prey and at higher rates were the subject of an experimental test, of
than counterparts who had been in captivity the feasibility of common reintroduction
longer (between 1 and 60 months). Ratsnakes strategies, using assessments of post‐release
which had been in captivity short‐term chose behaviour and physiological variables as
the correct arm (baited vs empty) of a three indicators of success (Roe et al. 2010). Three
arm feed choice maze, and approached prey groups of water snakes were compared, wild
faster, than snakes kept in captivity longer snakes at the study site, wild snakes translo-
term. Other variables such as time since last cated from their original range to the study
meal and body condition of snakes did not site, and snakes reared in captivity at acceler-
have an effect on feeding behaviour. There ated growth rates; a technique known as
also appeared to be relationships between the head‐starting where the aim is to maximise
type of prey cue provided and the snake reac- growth rates and thus survivability upon
tions. Ratsnakes held in captivity short term release. All animals were captured and radio
reacted to prey at greater rates than expected transmitters surgically inserted, after a
by chance after chemical and visual cues, and 7–11 day recovery all snakes were released
when they were combined; they responded into a 500 ha nature reserve managed by the
most quickly with a chemical cue alone. In nature conservancy in northeast Indiana,
contrast, ratsnakes held in captivity long term USA. Snakes were located once a week dur-
showed no trends, in either reaction to prey or ing the active season (May–Sep), every
latency to approach correct prey dependant two weeks during hibernation ingress and
on prey cue. The authors suggest that because egress and once per month for the overwin-
ratsnakes in captivity are generally managed tering period. The captive reared snakes
on a diurnal feeding pattern, that the longer moved less, traversed smaller areas of land,
they stay in captivity the less able they are to and selected inadequate (not representative
adapt to different prey items; which is prob- for the species) habitat; compared to the
lematic for a species which shifts from diurnal other two wild snake groups. The captive
to nocturnal feeding strategies in the wild reared snakes were also rarely observed
(DeGregorio et al. 2013). basking, foraging, or travelling and left their