Highlights:
- Synchronization
to coordinated vigilance was first reported from behavioural spectrum
analysis in birds.
- Synchronization of vigilance decreased and shifted as coordination
increased with disturbance and predation risk.
- Families with more juveniles were more vigilant.
- Vigilance could constitute a prime indicator in behaviour-based
tourist management.
- We recommend to keep tourists at least a distance of 400m away from
cranes.
Abstract: Prey monitor surrounding dangers independently or
cooperatively (synchronized and coordinated vigilance), with independent
and synchronized scanning being prevalent. Coordinated vigilance,
including unique sentinel behaviour, is rare in nature, since it is
time-consuming and benefit-limited. Evidence does not indicate animals
adopting alternative vigilance strategies during antipredation scanning.
Considering the cooperative nature of both synchronization and
coordination, we assessed whether group members could keep alert
synchronously or coordinatedly under different circumstances,
determining whether cooperative vigilance is context dependent. Under
the framework of conservation behavior, we studied how human behaviour
and species-specific variables impacted individual and collective
vigilance of globally threatened Black-necked Cranes (Grus
nigricollis ) and explored behaviour-based wildlife management. We
tested both predation risk (juveniles in group) and human disturbance
(level and distance) effects on individual and collective antipredation
vigilance of
black-necked
crane families. Adults spent significantly more time (proportion and
duration) on scanning than juveniles, and parents with juveniles behaved
more vigilant. Observer distance affected individual vigilance of adults
while juveniles were influenced by none of these variables. With the
number of juveniles and disturbance increased, crane couples decreased
synchronization of vigilance and they shifted to coordination, which has
so far never been reported yet. Similarly, with observer approaching,
adults shift vigilance from synchronization to coordination. The
collective vigilance shift from synchronization to coordination as a
function of observer distance could help us determining a safe distance
of c. 400m for the most vulnerable family groups with two
juveniles, so as no obvious interference with the threatened birds by
human proximity. We argue that vigilance behaviour could be a reliable
indicator in future nature-based tourist management and decision-making,
which can be derived from conservation solutions in nature.
Keywords: Anthropogenic disturbance; Collective vigilance;
Ecotourism; Nature visitation; Predation risk.