4. DISCUSSION
Despite extensive research on habitat selection, limited knowledge
exists regarding habitat selection status for individual species under
multivariate conditions. In this study, we investigated the habitat
selection patterns of D. splendidum across different sex and age
groups. Results indicated that adult males preferred higher tree
positions and areas with lower light intensity and moderate vegetation
density. Adults favored higher tree positions and more distant from
water sources. Juvenile males showed a preference for higher tree
positions, lower rock formations, and shrub and forest habitats while
avoiding herbaceous areas. Juvenile females preferred higher rock
habitats and or scrubby herbaceous areas.
The observed differences in habitat selection among individuals of
different sexes can may be attributed to variations in physiological
structure, living habits, and behavior (Conde et al., 2010; Eifler et
al., 2007). Adult males generally exhibited a preference for elevated
habitats within moderately vegetated environments, similar to the
preference for higher tree perches observed in territorial lizards such
as Anolis sagrei (Delaney et al., 2016). Male lizards tend to
occupy higher tree positions to enhance visibility for guarding
territory, engaging in interspecific communication, displaying behavior,
and foraging (Song et al., 2017). However, given the greater threats
inherent in occupying higher positions, males also prefer habitats with
denser vegetation to reduce their risk exposure (Browne et al., 2014;
Robert et al., 2006). Females, especially pregnant females, tend to
prefer areas with higher safety indices due to their significant
investment in reproduction (Eifler et al., 2012; Jerosch et al., 2018).
Our results indicated that females preferred lower tree positions or
higher rocks, which provide better opportunities to escape from
predators. and reduce risks associated with slower mobility, similar to
the preference for lower perches and higher foraging observed in female
arboreal lizards such as Anolis polylepis (Andrews, 1971).
Lizards are ectotherms and their physiology is influenced by external
conditions, especially light and temperature (Tan et al., 2019).
Notably, we found that adult females preferred higher light intensity,
likely to elevate their body temperature, enhance physiological and
biochemical responses, and promote gonadal development, thereby
influencing habitat selection decisions (Harvey et al., 2010; Melville
et al., 2001). Adult females also preferred higher vegetation densities,
further facilitating body temperature regulation (Melville et al.,
2001).
The differences in habitat selection among individuals of varying ages
may also be related to their developmental and physiological diversity
(Ficetola et al., 2013). Our findings indicated that adult lizards
typically preferred habitats with taller vegetation, which offer more
abundant food sources, better concealment, and an extensive canopy that
assists in thermoregulation. Vegetation characteristics in microhabitats
have been shown to facilitate thermoregulation in animals (Bradley et
al., 2022). Similarly, previous studies have revealed that preference
differences between adults and juveniles may help reduce ecological
niche competition and cannibalism, especially under high population
densities (Keren-Rotem et al., 2006). Our results indicated that
juvenile males, facing higher predation risks, tended to select larger
rocky shelters, shrubs, and ground-level sites in forested areas. This
behavior helps reduce daytime visual predator tracking, increase the
availability of retreat sites, and lower predation risk (Niewiarowski et
al., 1997). Similarly, Keren-Rotem et al. (2006) found that the juvenile
common chameleons (Chamaeleo chamaeleon ) prefer low grasslands
for concealment, while adults favor shrubs and trees. Our results also
demonstrated that adults preferred general or compacted substrate
conditions, similar to the habitat selection observed in rock lizards
(Iberolacerta bonnali ) (Arribas et al., 2009). This preference
aligns with the idea that both species select habitats that minimize
negative impacts, thereby facilitating escape or enhancing predation
rates (Song et al., 2017; Nemes et al., 2006; Mackey et al., 2010).
Our results revealed significant differences in habitat selection among
lizards based on sex and age classes, contributing to existing knowledge
on reptile habitat selection and enhancing our understanding of the
distribution and specific characteristics of these lizards.
Additionally, our findings offer theoretical support and scientific
guidance for the conservation of lizards and other species in the dry
and hot river valleys of the Hengduan Mountain region. However, the low
occurrence rate of lizards during winter and early spring in the study
area limited data collection. Consequently, only habitat selection data
from the breeding period were analyzed, as year-round data collection
was not feasible. It is important to note that habitat selection may
vary across seasons, and factors such as temporal migration and
interspecific interactions could influence specific habitat preferences
of individuals. Therefore, future research will continue to monitor
habitat changes influenced by various factors at different scales to
address and resolve these uncertainties.