File(s) stored somewhere else
Please note: Linked content is NOT stored on Macquarie University and we can't guarantee its availability, quality, security or accept any liability.
Niche partitioning within a population of seasnakes is constrained by ambient thermal homogeneity and small prey size
datasetposted on 2022-06-10, 02:40 authored by Rick ShineRick Shine, Claire Goiran, Greg BrownGreg Brown
In many populations of terrestrial snakes, an individual’s phenotype (e.g. body size, sex, colour) affects its habitat use. One cause for that link is gape-limitation, which can result in larger snakes eating prey that are found in different habitats. A second factor involves thermoregulatory opportunities, whereby individuals select habitats based upon thermal conditions. These ideas predict minimal intraspecific variation in habitat use in a species that eats small prey and lives in a thermally uniform habitat – such as the seasnake Emydocephalus annulatus, that feeds on tiny fish eggs and lives in inshore coral-reefs. To test that prediction, we gathered data on water depths and substrate attributes for 1475 sightings of 128 free-ranging E. annulatus in a bay near Noumea, New Caledonia. Habitat selection varied among individuals, but with a preference for coral-dominated substrates. A snake’s body size and reproductive state affected its detectability in deep water, but overall habitat use was not linked to snake body size, colour morph, sex, or pregnancy. A lack of ontogenetic shifts in habitat use allows extreme philopatry in E. annulatus, thereby reducing gene flow among populations and potentially, delaying recolonization after local extirpation events.
FAIR Self Assessment Rating