| Abstract | The concept of historic range of variability (HRV) is briefly evaluated
within the context of its application in ecosystem management
over the past two decades. Despite caveats to the contrary, an
implicit assumption continues to emerge of climatic stationarity,
and, by corollary, that presettlement centuries provide an appropriate
reference period. This is examined from the perspective of
historic climate change and ecosystem response. As a means of
developing reference prescriptions and management targets, HRV
is generally inappropriate, although if historic periods are used
for reconstruction that have coarse resemblance to present or projected
future climates, such as the Medieval Climate Anomaly or
middle Holocene rather than the presettlement centuries, these
might be defensible. In cases of reclamation of severely degraded
ecosystems, HRV prescriptions developed from analogous climate
periods could provide coarse guides. In most situations, however,
historic reconstructions are best used to improve understanding of
ecological response to a wide range of forcing factors, and thereby
to inform (rather than prescribe) management strategies. Such historically
informed approaches are likely more effective than an
HRV approach under future changing climate regimes for managing
and restoring ecosystem function and for assisting transitions
to new ecosystem states.
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