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Harvesting Wildlife. Greg Baxter School of Natural and Rural Systems Management The University of Queensland, Gatton Campus. Presentation to North Carolina State University University June 22, 2007. Wildlife includes living, wild harvested resources. Includes;
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Harvesting Wildlife Greg Baxter School of Natural and Rural Systems Management The University of Queensland, Gatton Campus Presentation to North Carolina State University University June 22, 2007
Wildlife includes living, wild harvested resources • Includes; • animals and their products (e.g. skins, ivory) • plants and their products (e.g. seeds, wax, natural pigments)
Types of harvesting • Commercial • e.g. whales or kangaroos • profit driven • large numbers (roos >2,000,000 p.a.) • harvest not always benefit to locals
Types of harvesting • Commercial • e.g. whales or kangaroos • profit driven • large numbers • Subsistence • to satisfy personal needs • can be large numbers, but local extent • now confined to Africa, S. America, parts of S.E. Asia
Types of harvesting • Commercial • e.g. whales or kangaroos • profit driven • large numbers • no benefit to locals • Subsistence • to satisfy personal needs • can be large numbers, but local extent • now confined to Africa, S. America, parts of S.E. Asia • ‘Bush meat’ • to meet demands of poor urban immigrants • driven by taste and cost • huge, growing demand • transport of products
Types of harvesting • Commercial • Subsistence • ‘Bush meat’ • to meet demands of poor urban immigrants • driven by taste and cost • huge, growing demand • transport of products • Cultural (including medicines) • e.g. dugongs by Aust. Aborigines, beluga whales by Inuit • small scale • local • can affect endangered/vulnerable species
Types of harvesting • Commercial • Subsistence • ‘Bush meat’ • Cultural • Collector (including trophy hunting) • people want to own exotic animals/products • want hunting experience • national and international • huge volumes • consumer divorced from consequences of collecting
Each type of harvesting • has different driver • different aerial extent • different mode of operation Therefore different modes of control/enforcement are applicable
Different harvesting requires different controls • Must be international
Different harvesting requires different controls • Must be international • Policing and enforcement insufficient
Different harvesting requires different controls • Must be international • Policing and enforcement insufficient • Must address poverty
Different harvesting requires different controls • Must be international • Policing and enforcement insufficient • Must address poverty • Must address cultural issues
Different harvesting requires different controls • Must be international • Policing and enforcement insufficient • Must address poverty • Must address cultural issues • Understand there powerful vested interests
Different harvesting requires different controls • Must be international • Policing and enforcement insufficient • Must address poverty • Must address cultural issues • Understand there powerful vested interests • Recognise economic and conservation outcomes can be achieved
Controlling Harvest • Quotas • Regulating effort • Spatial control
Quotas Preselected proportion of population(s) taken Requires; • Accurate & precise population estimate EACH harvest • Regular population monitoring (absolute abundance) • Good control over non-quota (illegal) take
Obtaining an estimate of absolute abundance • Time consuming • Costly • Complex An example from the kangaroo industry (Acknowledgement to Gordon Grigg)
Regulating Effort Limit how and/or when harvest can occur e.g. nest mesh size, rifle calibre, closed season(s) Requires; Does Not Require; • Compliance with regulations • Appropriate effort is specified • Monitoring of population trend • Estimate of absolute abundance Control is self-tracking with changes in population size
Spatial Control Limit WHERE animals can be taken, not how many, or how = places where animals can be harvested
Spatial Control Harvest between 0 – 100% in black squares Animals disperse into hunting areas Then, monitor trend in non-hunted areas
Monitoring in Spatial Control If population in non-hunted areas is about constant, maintain situation
Monitoring in Spatial Control If population in non-hunted areas is decreasing, restrict hunting areas
Monitoring in Spatial Control If population in non-hunted areas is increasing, increase hunting areas
Spatial Control Requires; Estimate of relative abundance – easy, cheap, repeatable Used; Fisheries, marine parks e.g. GBRMPA
Harvest Population Size How is harvest set for quotas? Assumes sustainable harvest Must understand the link between harvest size and population size and know what population size is
There are two population sizes (A & B) that will deliver any given SY Harvest at the higher one A B How is harvest set Sustained Yield (SY) Population Size
There is only one populations size (A) that will produce the maximum sustained yield (MSY). MSY A How is harvest set Sustained Yield (SY) Population Size
MSY Harvesting at MSY is dangerous Even a small error in population size estimate will lead to over-harvest Population usually discounted by 15% and population harvested there Sustained Yield (SY) A – 15% A Population Size
Can harvest have a conservation benefit? If the following conditions are met: • Benefit accrues to the land owner/occupier • Exploitation does not endanger the species (or look alikes) • Populations are monitored and managed • Exploitation enhances habitat