Pink-footed geese in Svalbard are a highly valued resource, but their increasing population causes conflicts with agricultural needs. USGS is devloping population models to help inform management of optimal harvest strategies.
The Science Issue and Relevance: As in North America, many goose populations in western Europe have increased dramatically during recent decades. The Svalbard population of pink-footed geese (Anser brachyrhynchus) is a good example, increasing from about 10,000 individuals in the early 1960s to roughly 80,000 today. Although these geese are a highly valued resource, the growing numbers of geese are causing agricultural conflicts in wintering and staging areas. Conservationists are also concerned that large numbers of geese may have deleterious impacts on the fragile tundra habitats used during the breeding season. Thus, there is the need for an internationally coordinated effort to manage the numbers of geese in a way that is consistent with recreational, economic, and conservation goals. The North American model of Adaptive Harvest Management has been suggested as a tool to help integrate social values and management capabilities with science-based predictions of population response.
Methods for Addressing the Issue: Informed management of wildlife harvests depends on the ability of a manager to take periodic actions, which are conditioned both on the current state of the resource and on anticipated future resource conditions. Optimal solutions to these “sequential-decision problems” can be calculated, provided there are clearly articulated management objectives, a set of alternative management actions, one or more models of resource dynamics, and a resource-monitoring program. This project will initially focus on the development of goose population models that can be used to inform management. The resulting model(s) will be used in combination with management objectives specified by the African-Eurasian Waterbird Agreement to derive optimal harvest strategies. Optimal harvest strategies can account for several sources and degrees of uncertainty, including uncertainty as to the most appropriate model of population dynamics. Using an iterative process of comparing model predictions with observations from the monitoring program, the most appropriate model can be identified. Thus, harvest strategies can “evolve” over time in response to what is learned.
Future Steps: Implementation of an adaptive-management strategy for pink-footed geese began in autumn of 2013. Current work is focused on expanding the application of adaptive management to taiga bean geese (Anser fabalis fabalis), barnacle geese (Branta leucopsis), and graylag geese (Anser anser).
Additional Products:
Johnson, F.A. and J. Madsen. 2015. Adaptive Harvest Management for the Svalbard Population of Pink-footed Geese. 2015 Progress Summary. Aarhus University, DCE – Danish Centre for Environment and Energy, 24 pp. Technical Report from DCE – Danish Centre for Environment and Energy No. 64.
Below are publications associated with this project.
Making do with less: Must sparse data preclude informed harvest strategies for European waterbirds?
Regulation of the hunting season as a tool for adaptive harvest management — First results for pink-footed geese Anser brachyrhynchus
Value of information in natural resource management: technical developments and application to pink-footed geese
Snow conditions as an estimator of the breeding output in high-Arctic pink-footed geese Anser brachyrhynchus
Uncertainty, robustness, and the value of information in managing an expanding Arctic goose population
- Overview
Pink-footed geese in Svalbard are a highly valued resource, but their increasing population causes conflicts with agricultural needs. USGS is devloping population models to help inform management of optimal harvest strategies.
Svalbard population of pink-footed geese (Anser brachyrhynchus) The Science Issue and Relevance: As in North America, many goose populations in western Europe have increased dramatically during recent decades. The Svalbard population of pink-footed geese (Anser brachyrhynchus) is a good example, increasing from about 10,000 individuals in the early 1960s to roughly 80,000 today. Although these geese are a highly valued resource, the growing numbers of geese are causing agricultural conflicts in wintering and staging areas. Conservationists are also concerned that large numbers of geese may have deleterious impacts on the fragile tundra habitats used during the breeding season. Thus, there is the need for an internationally coordinated effort to manage the numbers of geese in a way that is consistent with recreational, economic, and conservation goals. The North American model of Adaptive Harvest Management has been suggested as a tool to help integrate social values and management capabilities with science-based predictions of population response.
Methods for Addressing the Issue: Informed management of wildlife harvests depends on the ability of a manager to take periodic actions, which are conditioned both on the current state of the resource and on anticipated future resource conditions. Optimal solutions to these “sequential-decision problems” can be calculated, provided there are clearly articulated management objectives, a set of alternative management actions, one or more models of resource dynamics, and a resource-monitoring program. This project will initially focus on the development of goose population models that can be used to inform management. The resulting model(s) will be used in combination with management objectives specified by the African-Eurasian Waterbird Agreement to derive optimal harvest strategies. Optimal harvest strategies can account for several sources and degrees of uncertainty, including uncertainty as to the most appropriate model of population dynamics. Using an iterative process of comparing model predictions with observations from the monitoring program, the most appropriate model can be identified. Thus, harvest strategies can “evolve” over time in response to what is learned.
Future Steps: Implementation of an adaptive-management strategy for pink-footed geese began in autumn of 2013. Current work is focused on expanding the application of adaptive management to taiga bean geese (Anser fabalis fabalis), barnacle geese (Branta leucopsis), and graylag geese (Anser anser).
Additional Products:
Johnson, F.A. and J. Madsen. 2015. Adaptive Harvest Management for the Svalbard Population of Pink-footed Geese. 2015 Progress Summary. Aarhus University, DCE – Danish Centre for Environment and Energy, 24 pp. Technical Report from DCE – Danish Centre for Environment and Energy No. 64.
- Publications
Below are publications associated with this project.
Making do with less: Must sparse data preclude informed harvest strategies for European waterbirds?
The demography of many European waterbirds is not well understood because most countries have conducted little monitoring and assessment, and coordination among countries on waterbird management has little precedent. Yet intergovernmental treaties now mandate the use of sustainable, adaptive harvest strategies, whose development is challenged by a paucity of demographic information. In this study,AuthorsFred A. Johnson, Mikko Alhainen, Anthony D. Fox, Jesper Madsen, Matthieu GuillemainRegulation of the hunting season as a tool for adaptive harvest management — First results for pink-footed geese Anser brachyrhynchus
Adjustment of hunting season length is often used to regulate harvest of waterbirds but the effects are disputed. We describe the first results of season length extension on the harvest of the pink-footed goose, which has been selected as the first test case of adaptive harvest management of waterbirds in Europe. In Denmark, the season (previously 1 September to 31 December) was extended to includAuthorsJesper Madsen, Kevin K. Clausen, Thomas K. Christensen, Fred A. JohnsonValue of information in natural resource management: technical developments and application to pink-footed geese
The “value of information” (VOI) is a generic term for the increase in value resulting from better information to guide management, or alternatively, the value foregone under uncertainty about the impacts of management (Yokota and Thompson, Medical Decision Making 2004;24: 287). The value of information can be characterized in terms of several metrics, including the expected value of perfect inforAuthorsByron K. Williams, Fred A. JohnsonSnow conditions as an estimator of the breeding output in high-Arctic pink-footed geese Anser brachyrhynchus
The Svalbard-breeding population of pink-footed geese Anser brachyrhynchus has increased during the last decades and is giving rise to agricultural conflicts along their migration route, as well as causing grazing impacts on tundra vegetation. An adaptive flyway management plan has been implemented, which will be based on predictive population models including environmental variables expected to aAuthorsGitte Høj Jensen, Jesper Madsen, Fred A. Johnson, Mikkel P. TamstorfUncertainty, robustness, and the value of information in managing an expanding Arctic goose population
We explored the application of dynamic-optimization methods to the problem of pink-footed goose (Anser brachyrhynchus) management in western Europe. We were especially concerned with the extent to which uncertainty in population dynamics influenced an optimal management strategy, the gain in management performance that could be expected if uncertainty could be eliminated or reduced, and whether anAuthorsFred A. Johnson, Gitte H. Jensen, Jesper Madsen, Byron K. Williams