DOI: 10.5061/dryad.k46r2
title: Data from: Mechanism matters: the cause of fluctuations in boom-bust populations governs optimal habitat restoration strategy

description: Many populations exhibit boom-bust dynamics in which abundance fluctuates
 dramatically over time. Past research has focused on identifying whether
 the cause of fluctuations is primarily exogenous, e.g., environmental
 stochasticity coupled with weak density dependence, or endogenous, e.g.,
 over-compensatory density dependence. Far fewer studies have addressed
 whether the mechanism responsible for boom-bust dynamics matters with
 respect to at-risk species management. Here, we ask whether the best
 strategy for restoring habitat across a landscape differs under
 exogenously versus endogenously driven boom-bust dynamics. We used
 spatially explicit individual-based models to assess how butterfly
 populations governed by the two mechanisms would respond to habitat
 restoration strategies that varied in the level of resource patchiness –
 from a single large patch to multiple patches spaced at different
 distances. Our models showed that the restoration strategy that minimized
 extinction risk and boom-bust dynamics would be markedly different
 depending on the governing mechanism. Exogenously governed populations
 fared best in a single large habitat patch, whereas for endogenously
 driven populations, boom-bust dynamics were dampened and extinction risk
 declined when the total restored area was split into multiple patches with
 low to moderate inter-patch spacing. Adding environmental stochasticity to
 the endogenous model did not alter this result. Habitat fragmentation
 lowered extinction risk in the endogenously driven populations by reducing
 their growth rate, precluding both “boom” phases and, more importantly,
 “bust” phases. Our findings suggest that: 1) successful restoration will
 depend on understanding the causes of fluctuations in at-risk populations;
 2) the level and pattern of spatiotemporal environmental heterogeneity
 will also affect the ideal management approach; and 3)
 counter-intuitively, for at-risk species with endogenously governed
 boom-bust dynamics, lowering the intrinsic population growth rate may
 decrease extinction risk.
description: Endogenous
 ModelNetlogo file containing
 code, user interface, and information tab describing this model and how to
 use it. This model simulates boom-bust dynamics of a butterfly species via
 endogenous consumer-resource density dependent
 dynamics.HimesBoor_EcAp_TCB_Endog.nlogoExogenous ModelNetlogo file containing code, user interface, and information tab describing this model and how to use it. This model simulates boom-bust dynamics of a butterfly species via exogenous dynamics including a population ceiling and environmental stochasticity.HimesBoor_EcAp_TCB_Exog.nlogoNumber of patches lookup tableLookup table read by Netlogo code.new-scenario-#patch-lookup4.txtDistance between patches lookup tableLookup table read by Netlogo code.new-scenario-dist-lookup.txtMap - Scenario 1.0Landscape map portraying restoration Scenario 1.0TCB_Scen1.0_map.txtTCB_Scen2.1b_mapLandscape map portraying restoration Scenario 2.1TCB_Scen2.2b_mapLandscape map portraying restoration Scenario 2.2TCB_Scen2.3b_mapLandscape map portraying restoration Scenario 2.3TCB_Scen2.4b_mapLandscape map portraying restoration Scenario 2.4TCB_Scen2.5b_mapLandscape map portraying restoration Scenario 2.5TCB_Scen3.1b_mapLandscape map portraying restoration Scenario 3.1TCB_Scen3.2b_mapLandscape map portraying restoration Scenario 3.2TCB_Scen3.3b_mapLandscape map portraying restoration Scenario 3.3TCB_Scen3.4b_mapLandscape map portraying restoration Scenario 3.4TCB_Scen3.5b_mapLandscape map portraying restoration Scenario 3.5TCB_Scen4.1b_mapLandscape map portraying restoration Scenario 4.1TCB_Scen4.2b_mapLandscape map portraying restoration Scenario 4.2TCB_Scen4.3b_mapLandscape map portraying restoration Scenario 4.3TCB_Scen4.4b_mapLandscape map portraying restoration Scenario 4.4TCB_Scen4.5b_mapLandscape map portraying restoration Scenario 4.5TCB_Scen5.1b_mapLandscape map portraying restoration Scenario 5.1TCB_Scen5.2b_mapLandscape map portraying restoration Scenario 5.2TCB_Scen5.3b_mapLandscape map portraying restoration Scenario 5.3TCB_Scen5.4b_mapLandscape map portraying restoration Scenario 5.4TCB_Scen5.5b_mapLandscape map portraying restoration Scenario 5.5TCB_Scen6.1b_mapLandscape map portraying restoration Scenario 6.1TCB_Scen6.2b_mapLandscape map portraying restoration Scenario 6.2TCB_Scen6.3b_mapLandscape map portraying restoration Scenario 6.3TCB_Scen6.4b_mapLandscape map portraying restoration Scenario 6.4TCB_Scen6.5b_mapLandscape map portraying restoration Scenario 6.5TCB_Scen7.1b_mapLandscape map portraying restoration Scenario 7.1TCB_Scen7.2b_mapLandscape map portraying restoration Scenario 7.2TCB_Scen7.3b_mapLandscape map portraying restoration Scenario 7.3TCB_Scen7.4b_mapLandscape map portraying restoration Scenario 7.4TCB_Scen7.5b_mapLandscape map portraying restoration Scenario 7.5