316 Monitoring Threatened Species and Ecological Communities
Designing a monitoring program requires a hierarchy of cascading decisions
(i.e. what to monitor, how much to invest, etc.). The choice of what to monitor is
inf luenced by legislative/agency requirements, historical effort, conservation
status, individual interests, cultural significance and/or public interest, as well as
consideration of the costs and feasibility of monitoring. However, Chapters 16 and
17 describe how quantitative tools – such as the project prioritisation protocol
(PPP) or expected value of perfect information (EVPI) – can aid decision making
by providing a transparent and repeatable rationale for investing more heavily in
monitoring one species over another. For example, Chapter 17 describes how the
PPP has prioritised management/monitoring for NSW Saving Our Species (SoS)
project. Prioritisation scores were used to weight investment in each species, based
on the expected benefit of managing/monitoring, the likelihood of success, and the
estimated cost. Species with that greatest expected return-on-investment are
favoured in the PPP model.
Once target species are selected, yet more decisions follow: managers must
decide which population metrics to track, the type of monitoring methods/
techniques deployed, the duration of the monitoring program, the number and
location of sites, the frequency of visits to sites and the duration/intensity of
monitoring each visit. To further complicate decisions, managers must also decide
how, when and where to monitor for threats so that the drivers of population
declines can be identified, particularly if the relationships between a threatened
species and threats are poorly understood. Such decisions are far from simple:
managers usually have limited money at their disposal, which creates trade-offs
between how resources can be spent. The biology and distribution of threatened
species can be poorly understood, which makes it unclear about how, when and
where to monitor, and threatened species are often on the brink of extinction,
which means monitoring decisions need to be made urgently.
The design of a monitoring program for threatened species or ecological
communities will depend primarily on the fundamental objective of monitoring
and should be fit-for-purpose. Monitoring should have clear objectives, which are
linked to management, are based on the current state of knowledge at the time, and
have a clearly defined methodology. In the case of threatened species, the goal is
usually to avoid extinction, so monitoring generally focuses on population states
such as occupancy, population size, growth rate, survival rates and/or distribution;
however, collecting additional data on life history/demography can provide
important insight. The choice of which population state to monitor will be
inf luenced by the biology of the species, the environment where it is found (i.e.
marine v. terrestrial), the extent of its distribution, who will be doing the
monitoring (i.e. citizen scientists v. field ecologists; Chapters 25–28, 31), as well as
the cost, feasibility and limitations of alternative survey methods.
Regardless of the choice of population state to monitor, our ability to estimate
the true state of interest will be inf luenced by biases such as detectability,