The Vertebrate Fauna of Jenolan Karst Conservation Reserve: Final

Table 12: Scientific issues to consider In relation to monitoring programs
Issue Description
Have clear, simple goals and
test well defined hypotheses
Develop reliable and useful
indicators
Have a well thought out survey
design that uses appropriate
stratification
Have enough sites and
therefore enough statistical
power to detect change
Clearly define the type of data
the monitoring program sets
out to collect
Employ appropriate survey
methods for the desired data
type
Be undertaken at an appropriate
temporal scale, and most
importantly have on-going
commitment for the long-term
Set limits of acceptable change
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Monitoring programs that have very broad aims, or vague hypotheses, or
are too ambitious in terms of the number of questions they try to answer,
often fail. It is important to keep things simple.
Choosing the right indicators requires careful thought to ensure they will
provide information that clearly relates to the issue that you want to monitor.
For example, monitoring a hard to find fauna species to inform of the health
of fauna overall will be more resource intensive than using a common
species.
Again, a simple design that is limited to a particular species, or a few or
perhaps limiting the subject of the monitoring to one suite of species, will
give the monitoring project a better chance of success.
A simple calculation can be done a priori to determine the minimum sample
size needed to have sufficient power. Too few survey sites will guarantee
that a monitoring program will either fail to detect change, or give an
unreliable or misleading result.
For example, presence/absence of species at the site scale which can be
regionally summarised as species x was present at 10 out of 18 sites in the
region; OR breeding success of a species per year, OR number of
individuals of a species per unit effort.
For example you might choose one method to generate presence/absence
data, but another to obtain abundance estimates. This needs to be thought
about and planned for at the concept stage of planning.
Most monitoring projects need at least 5 years worth of data to detect
change, whereas many will need much longer than that (IUCN red list
criteria suggest that 10 years (or 3 x generation length) of data is the
minimum amount needed to adequately assess trends over time see
http://www.iucnredlist.org/technical-documents/categories-and-criteria for
more detail). The number of years needed for monitoring will depend on the
frequency of monitoring, the methods used and the biology, in particular the
life history of the species or suite of species being monitored. Monitoring
anything for less than 5 years is a waste of time and resources, as
statistically, you will likely need many more than 5 data points to confidently
interpret any observed trend.
This is an important aspect of monitoring that many programs omit. It is
easy at the conclusion of a monitoring program to say, “Species x declined
by 60% over 30 years”, however it is often too late to use this information
and the population has changed beyond recovery. Information that a decline
is occurring at present is much more useful, so that something can be done
to halt or reverse the decline. Hence, there must be a limit of acceptable
change set for all monitoring programs. This will define a point of “worry”,
and help to facilitate a feedback loop for adaptive management. There will
always be a small amount of change due to natural fluctuations, e.g.
drought, however this amount of expected natural fluctuation needs to be
estimated and a sensible limit of acceptable change determined. For
example, you might set an acceptable limit of change for the abundance of a
certain species to be +/- 8% annually (this translates into the species being
at risk of extinction within 20 years), and for the first 3 years, the population
has shown a 2% increase, then a 2% decline, then a 4% decline, then in the
4 th year, the population drops by 9%. Because we have set 8% as the
“worry” point, we know that we need to act to halt or reverse this decline.
The relevant land managers should be made aware and act accordingly,
maybe stepping up predator control, or investigating other threats.
The Vertebrate Fauna of Jenolan Karst Conservation Reserve