Download Science for Conservation Insufficient monitoring may obscure true

Science for Conservation
Insufficient monitoring may obscure true outcomes of
restoration projects
Gregory H. Golet, Thomas Gardali, John W. Hunt, David A. Koenig, and Neal M. Williams. 2010. Temporal and taxonomic variability
in response of fauna to riparian restoration. Restoration Ecology doi: 10.1111/j.1526-100X.2009.00525.x. Contact: [email protected]
Ecologists spend a lot of time and money
attempting to restore biodiversity to degraded
ecosystems. Restoration methods vary, but the
goal is usually the same: to bring back onceabundant native species and all their complex
biological interactions.
Vertebrates were more consistent across sites
than invertebrates. And among vertebrates, more
mobile animals like birds were distributed more
evenly across the landscape than their sedentary
counterparts, the rodents, which were sometimes
abundant, but other times not.
To assess whether restoration efforts are working,
researchers often conduct native species surveys
in restored areas and compare what they find to
nearby natural areas. However, tracking all
organisms of interest is impractical, so
researchers typically choose to monitor a limited
number of species under the assumption that their
response will parallel that of the broader
ecological community.
These findings suggest that evaluations of
restoration success based on short-term studies of
single groups of species may not accurately
represent the response of the broader ecological
community.
However, instead of monitoring an array of
species—a variety of insects, birds, mammals,
rodents and fish, for example—most restoration
response studies only focus on a single type of
animal (perhaps reflecting the particular expertise
of the scientists involved.) Moreover, site
assessments are typically short-lived, even
though it is widely recognized that site conditions
change as sites mature.
Authors of a recent article in Restoration Ecology
explored the limitations of such studies by
examining how birds, rodents, bees and beetles
(Figure 1) responded to restoration along the
Sacramento River for up to five years. They
found that responses to restoration varied among
the different types of species. In other words,
success for one group did not necessarily imply
success for the others. They also found that the
relative success of different restoration sites
varied over time, suggesting that the impact of
restoration activities cannot be accurately
determined from one-time assessments.
In addition, the researchers found that certain
groups of animals were more spatially variable in
their response to restoration than others.
The Nature Conservancy
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Figure 1: Focal taxa for the Sacramento River
restoration study
Key points

Most assessments of restoration success
track a single type of species over a
single season.

When a variety of species are
monitored, restoration response is
shown to vary across species and over
time.

Robust restoration assessments should
examine the response of multiple types
of species over multiple seasons and
years.
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