Synthesis of chaos and sustainability in a nonstationary linear dynamic model of the American black bear (Ursus americanus pallas) in the Adirondack Mountains of New York

Black bears on the 6000-ha Huntington Wildlife Forest, in the central Adirondack region of upper New York State, were modeled using the STELLA II Simulation software. The purposes were to (1) express black-bear biology as a population system inseparably derived from its ecosystem; (2) demonstrate how chaos, with origins in nonlinearity, and sustainability, related to linearity, can be incorporated into dynamical models, minimizing the use of mathematics that may not be well-chosen due to an inadequate rationale; and (3) demonstrate how qualitative biology, natural history, and ecology can be realistically built into a model despite many unknowns and initially limited data. A rationale is presented for synthesizing chaos and sustainability in ecological models. From this and the good behavioral properties observed in simulated baseline and sensitivity dynamics, it is concluded that a useful approach in ecological modelling may be to put nonlinear attributes into the parameter space and linear ones into the state space to conform the two opposed properties of well-behavedness and surprise. The role of linearity in modelling, and in formulating humanity's future ecological paradigm of existence, should not be overlooked. (C) 1997 Elsevier Science B.V.