Flying the North American Adirondack whitetail on instrumentsA multi-parameter modeling approach to ecosystem-based wildlife management

Abstract

We compare ecosystem-based wildlife management to instrument flight of aircraft. Airplanes cannot be controlled without visual ground reference, or if this is impossible to a cluster of flight instruments. Instrument pilots are trained to develop a rhythmic scan of the cluster to monitor and correct flight path and attitude. The untrained tendency is to fixate on a single gauge. Then, the aircraft deviates from its desired attitude and trajectory, and control may be lost. Fixation is like single-factor management wherein variables like habitat quality, recruitment, predator control, or harvest rates are singled out for adjustment without considering the others. Ungulate populations are no less complex than aircraft in flight. They are multifactorial and move through time and space. To be managed effectively they must be guided in these movements through the monitoring and control instruments nature has provided. These are not necessarily proximate because populations are embedded in ecosystems and cannot be isolated from systemic complexity. Holistic management is needed, which requires a suite of monitoring and control parameters analogous to those in instrument flight. We hold that every institution serving the interests of wise resource use should employ comprehensive, large-scale, ecosystem-based models built, tested, and perfected as a committed institutional activity over long periods of time. We call this Institutionalized Model-Making (IMM), and see models drawn from the collective expertise of scientists and their data in the same relation to nature as flight simulators are to actual aircraft. They mimic responses to control actions, and enable training in multifactorial management analogous to the instrument scans and control actions of the instrument pilot. A model comprehensive enough for institutional use has not been built. We call attention to our efforts to develop such a model at the Huntington Wildlife Forest in New York's Adirondack Mountains. This is a model of the North American whitetail deer ( Odocoileus virginianus Miller). It is too complex and incomplete for use in this paper, so a smaller-scale model is employed to make the case. In simulation trials parameters are ranked as to control sensitivity, then manipulated singly and multiply to demonstrate the superiority of the multiparameter approach.