Modelling for Pest Risk Analysis: Spread and Economic Impacts
Author(s)
Carrasco Torrecilla, Luis Roman
Type
Thesis
Abstract
The introduction of invasive pests beyond their natural range is one of the main
causes of the loss of biodiversity and leads to severe costs. Bioeconomic models that
integrate biological invasion spread theory, economic impacts and invasion
management would be of great help to increase the transparency of pest risk
analysis (PRA) and provide for more effective and efficient management of invasive
pests.
In this thesis, bioeconomic models of management of invasive pests are developed.
The models are applied to three cases of study. The main case looks at the invasion
in Europe by the western corn rootworm (WCR), Diabrotica virgifera ssp. virgifera
LeConte (Coleoptera: Chrysomelidae). A range of quantitative modelling approaches
was employed: (i) dispersal kernels fitted to mark-release-recapture experimental
data; (ii) optimal control models combined with info-gap theory; (iii) spatially explicit
stochastic simulation models; and (iv) agent-based models.
As a result of the application of the models new insights on the management of
invasive pests and the links between spread and economic impacts were gained: (i)
current official management measures to eradicate WCR were found to be
ineffective; (ii) eradication and containment programmes that are economically
optimal under no uncertainty were found out to be also the most robustly immune
policy to unacceptable outcomes under severe uncertainty; (iii) PRA focusing on
single invasive pests might lead to management alternatives that dot not correspond
to the optimal economic allocation if the rest of the invasive pests sharing the same management budget are considered; (iv) the control of satellite colonies of an
invasion occurring by stratified dispersal is ineffective when a strong propagule
pressure is generated from the main body of the invasion and this effect is increased
by the presence of human-assisted long-distance dispersal; and (v) agent-based
models were shown to be an adequate tool to integrate biological invasion spread
models with economic analysis models.
causes of the loss of biodiversity and leads to severe costs. Bioeconomic models that
integrate biological invasion spread theory, economic impacts and invasion
management would be of great help to increase the transparency of pest risk
analysis (PRA) and provide for more effective and efficient management of invasive
pests.
In this thesis, bioeconomic models of management of invasive pests are developed.
The models are applied to three cases of study. The main case looks at the invasion
in Europe by the western corn rootworm (WCR), Diabrotica virgifera ssp. virgifera
LeConte (Coleoptera: Chrysomelidae). A range of quantitative modelling approaches
was employed: (i) dispersal kernels fitted to mark-release-recapture experimental
data; (ii) optimal control models combined with info-gap theory; (iii) spatially explicit
stochastic simulation models; and (iv) agent-based models.
As a result of the application of the models new insights on the management of
invasive pests and the links between spread and economic impacts were gained: (i)
current official management measures to eradicate WCR were found to be
ineffective; (ii) eradication and containment programmes that are economically
optimal under no uncertainty were found out to be also the most robustly immune
policy to unacceptable outcomes under severe uncertainty; (iii) PRA focusing on
single invasive pests might lead to management alternatives that dot not correspond
to the optimal economic allocation if the rest of the invasive pests sharing the same management budget are considered; (iv) the control of satellite colonies of an
invasion occurring by stratified dispersal is ineffective when a strong propagule
pressure is generated from the main body of the invasion and this effect is increased
by the presence of human-assisted long-distance dispersal; and (v) agent-based
models were shown to be an adequate tool to integrate biological invasion spread
models with economic analysis models.
Date Issued
2009
Date Awarded
2009-12
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Mumford, John
Knight, Jon
MacLeod, Alan
Baker, Richard
Sponsor
DEFRA
Creator
Carrasco Torrecilla, Luis Roman
Grant Number
NB 53 9005 and RES-229-25-0005
Publisher Department
Centre for Environmental Policy
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)