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1.
J Environ Manage ; 200: 6-21, 2017 Sep 15.
Article in English | MEDLINE | ID: mdl-28549304

ABSTRACT

Wetlands in the region of Southern Ontario, Canada have declined substantially from their historic area. Existing regulations and programs have not abated this decline. However, reversing this trend by protecting or restoring wetlands will increase the supply of important ecosystem services. In particular, these actions will contribute to moderating the impacts of extreme weather predicted to result from climate change as well as reducing phosphorous loads in Lake Erie and ensuing eutrophication. Since the majority of land in the region is privately owned, landowners can play an important role. Thus, we assessed landowner preferences for voluntary incentive-based wetlands conservation programs using separate choice experiments mailed to farm and non-farm landowners in the Grand River and Upper Thames River watersheds. Latent class models were separately estimated for the two data sets. Marginal willingness to accept, compensating surplus, and participation rates were estimated from the resulting models to gain insight into the financial compensation required by landowners and their potential participation. Many of the participating landowners appear willing to participate in wetlands conservation at reasonable cost, with more willing groups notably marked by past participation in incentive-based conservation programs. They generally favor wetlands conservation programs that divert smaller areas of land to wetlands conservation, target marginal agricultural land, use treed buffers to protect wetlands, offer technical help, and pay financial incentives. However, landowners appear reluctant to receive public recognition of their wetland conservation actions. Our results are of interest to natural resource managers designing or refining wetlands conservation programs.


Subject(s)
Climate Change , Conservation of Natural Resources , Wetlands , Ecosystem , Ontario
2.
Theor Popul Biol ; 103: 71-83, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25963631

ABSTRACT

This study develops a quantitative framework for estimating the effects of extreme suspended-sediment events (SSC>25 mg L(-1)) on virtual populations of Chinook (Oncorhynchus tshawytscha) and coho (O. kisutch) salmon in a coastal watershed of British Columbia, Canada. We used a life history model coupled with a dose-response model to evaluate the populations' responses to a set of simulated suspended sediments scenarios. Our results indicate that a linear increase in SSC produces non-linear declining trajectories in both Chinook and coho populations, but this decline was more evident for Chinook salmon despite their shorter fresh-water residence. The model presented here can provide insights into SSC impacts on population responses of salmonids and potentially assist resource managers when planning conservation or remediation strategies.


Subject(s)
Geologic Sediments , Salmon/physiology , Animals , British Columbia , Life Cycle Stages , Monte Carlo Method , Reproduction
3.
Ecol Appl ; 19(7): 1693-707, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19831064

ABSTRACT

Nepal's greater one-horned rhinoceros (Rhinoceros unicornis) faces serious threats from poaching. Poaching of these rhinos is a complex problem, influenced by such diverse factors as the price of rhino horn on the international market, local socioeconomic factors, and the population dynamics of the species. Few studies have attempted to address this complexity. In this study, we model the poaching and population dynamics of the one-horned rhinoceros within an integrated framework of ecological, socioeconomic, political, and legal dimensions. The poaching model for rhinos in Royal Chitwan National Park (RCNP) in Nepal is combined with the population model for the species within a simulation framework and explored under various alternative policy scenarios with differing external socioeconomic and political conditions as well as internal policy response. We predict that, under the current (2003-2005) rhino conservation strategy, poaching would continue to be a major threat to the rhino population in RCNP. Furthermore, the internal policy response must begin to consider external factors such as socioeconomic conditions within the park buffer zone to be more effective in the long run. Finally, we find that, for long-run control, antipoaching policies should be directed at increasing the opportunity costs of poaching by creating better alternative economic opportunities, and at antipoaching enforcement.


Subject(s)
Conservation of Natural Resources , Crime/economics , Ecosystem , Perissodactyla , Animals , Law Enforcement , Models, Economic , Nepal , Politics , Population Dynamics , Public Policy , Time Factors
4.
Biol Rev Camb Philos Soc ; 81(2): 163-82, 2006 May.
Article in English | MEDLINE | ID: mdl-16336747

ABSTRACT

Freshwater biodiversity is the over-riding conservation priority during the International Decade for Action - 'Water for Life' - 2005 to 2015. Fresh water makes up only 0.01% of the World's water and approximately 0.8% of the Earth's surface, yet this tiny fraction of global water supports at least 100000 species out of approximately 1.8 million - almost 6% of all described species. Inland waters and freshwater biodiversity constitute a valuable natural resource, in economic, cultural, aesthetic, scientific and educational terms. Their conservation and management are critical to the interests of all humans, nations and governments. Yet this precious heritage is in crisis. Fresh waters are experiencing declines in biodiversity far greater than those in the most affected terrestrial ecosystems, and if trends in human demands for water remain unaltered and species losses continue at current rates, the opportunity to conserve much of the remaining biodiversity in fresh water will vanish before the 'Water for Life' decade ends in 2015. Why is this so, and what is being done about it? This article explores the special features of freshwater habitats and the biodiversity they support that makes them especially vulnerable to human activities. We document threats to global freshwater biodiversity under five headings: overexploitation; water pollution; flow modification; destruction or degradation of habitat; and invasion by exotic species. Their combined and interacting influences have resulted in population declines and range reduction of freshwater biodiversity worldwide. Conservation of biodiversity is complicated by the landscape position of rivers and wetlands as 'receivers' of land-use effluents, and the problems posed by endemism and thus non-substitutability. In addition, in many parts of the world, fresh water is subject to severe competition among multiple human stakeholders. Protection of freshwater biodiversity is perhaps the ultimate conservation challenge because it is influenced by the upstream drainage network, the surrounding land, the riparian zone, and - in the case of migrating aquatic fauna - downstream reaches. Such prerequisites are hardly ever met. Immediate action is needed where opportunities exist to set aside intact lake and river ecosystems within large protected areas. For most of the global land surface, trade-offs between conservation of freshwater biodiversity and human use of ecosystem goods and services are necessary. We advocate continuing attempts to check species loss but, in many situations, urge adoption of a compromise position of management for biodiversity conservation, ecosystem functioning and resilience, and human livelihoods in order to provide a viable long-term basis for freshwater conservation. Recognition of this need will require adoption of a new paradigm for biodiversity protection and freshwater ecosystem management - one that has been appropriately termed 'reconciliation ecology'.


Subject(s)
Biodiversity , Conservation of Natural Resources , Ecosystem , Environment , Fresh Water , Animals , Humans , Population Density , Population Dynamics , Species Specificity , Water Supply
5.
J Environ Manage ; 69(3): 261-73, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14580727

ABSTRACT

Changes in land use can potentially reduce the quality of fish habitat and affect the economic value of commercial and sport fisheries that rely on the affected stocks. Parks and protected areas that restrict land-use activities provide benefits, such as ecosystem services, in addition to recreation and preservation of wildlife. Placing values on these other benefits of protected areas poses a major challenge for land-use planning. In this paper, we present a framework for valuing benefits for fisheries from protecting areas from degradation, using the example of the Strait of Georgia coho salmon fishery in southern British Columbia, Canada. Our study improves upon previous methods used to value fish habitat in two major respects. First, we use a bioeconomic model of the coho fishery to derive estimates of value that are consistent with economic theory. Second, we estimate the value of changing the quality of fish habitat by using empirical analyses to link fish population dynamics with indices of land use in surrounding watersheds. In our example, we estimated that the value of protecting habitat ecosystem services is C$0.93 to C$2.63 per ha of drainage basin or about C$1322 to C$7010 per km of salmon stream length (C$1.00=US$0.71). Sensitivity analyses suggest that these values are relatively robust to different assumptions, and if anything, are likely to be minimum estimates. Thus, when comparing alternative uses of land, managers should consider ecosystem services from maintaining habitat for productive fish populations along with other benefits of protected areas.


Subject(s)
Conservation of Natural Resources , Environment Design , Fisheries , Models, Economic , Oncorhynchus kisutch , Animals , Animals, Wild , British Columbia , Cost-Benefit Analysis , Ecosystem , Population Dynamics , Quality Control , Recreation , Water Pollution/prevention & control
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