6 – The extent and adequacy of monitoring for Australian threatened reptile species^73both species mysteriously disappeared from the area between 1998 and 2002,
notwithstanding more intensive monitoring effort, repeated visits to sites where
these species were formerly abundant, and no obvious threats (Guinea and
Whiting 2005; Lukoschek et al. 2013). This monitoring program demonstrated the
extirpation of at least these two species from that site. Fortunately, some
subsequent records from monitoring of trawl samples and other sources have
demonstrated persistence for both species, albeit beyond their previously known
distributions (Sanders et al. 2015; D’Anastasi et al. 2016).
Monitoring for some threatened reptile species, particularly marine and some
freshwater turtles, is notable in including consideration not only of trends in
incidence and abundance but also of critical life history parameters. A notable
example is for the white-throated snapping turtle Elseya albagula, for which
monitoring has demonstrated negligible reproductive success, due to predation of
eggs and hatchlings by introduced predators and trampling of clutches by stock.
Hence, although the population is currently declining at only a slow rate (because
adults are long-lived and have low annual mortality), its age structure is
undergoing marked change and its long-term viability is low, unless intensive
remedial management can be directed towards better protection of its breeding
habitat and nest sites (Threatened Species Scientific Committee 2014).
For many marine turtles, monitoring programs include not only trends from
long-established counts of breeding females at nesting beaches, but also ongoing
assessments of reproductive success (and the factors affecting it), adult survival and
population age structure, and broad-scale movement patterns (increasingly
through satellite telemetry). Some monitoring programs for marine turtles also
assess trends in the extent, intensity and impacts of many threats (including
entanglement in marine debris, contamination with pollutants, coastal
development, mining and gas operations, fishing by-catch, traditional harvest and
climate change) and of the efficacy of management responses to those threats
(Environment Australia 2003). The substantial evidence base derived from such
monitoring allows for the development and application of sophisticated models of
life history and population viability, and the strategic investment of management
actions that can make most effective contributions to recovery (Chaloupka and
Limpus 2005).
Assessment of monitoring of threatened reptiles
The extent and adequacy of monitoring for the set of Australian threatened reptile
species is evaluated here using the monitoring assessment framework described in
Chapter 2. This framework includes nine evaluation metrics (fit-for-purpose,
coverage, periodicity, longevity, design quality, coordination, data availability and
reporting, management linkage, and demographic parameters).