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Eradication of alien crayfish populations - GB non
Eradication of alien crayfish populations - GB non

... crayfish abundance in these atypical habitats can vary enormously from year to year, due to unknown but apparently natural causes. The species does not occur naturally in Scotland. There are also catchments in the far southwest of England and parts of west Wales where it has not been recorded. This ...
oribi antelope - Conservation Breeding Specialist Group
oribi antelope - Conservation Breeding Specialist Group

... Even though Oribi have a wide distribution on the African continent, stretching from Senegal towards Ethiopia and southwards towards South Africa, it is patchily and discontinuously distributed within this area as a result of specific habitat requirements (Adamczak, 1999). In South Africa, Oribi are ...
Recovery Strategy for the Boreal Caribou in the NWT (2017)
Recovery Strategy for the Boreal Caribou in the NWT (2017)

... Boreal caribou in the NWT inhabit an extensive area of boreal forest east of the mountains as far north as Tuktoyaktuk. The range is continuous with northern Alberta and northern British Columbia to the south, although boreal caribou there are considered different populations for management purposes ...
Management plan for the lynx population in Finland
Management plan for the lynx population in Finland

... out people’s views, expectations and demands relating to lynx and lynx policy, on a regional basis. The groups targeted were those whose daily lives are affected by the presence of lynx. Other target groups were organisations and authorities that in one way or another have to do with nature conserva ...
2008. Scientific Review for the Identification of Critical Habitat
2008. Scientific Review for the Identification of Critical Habitat

... hierarchical process with considerations across multiple spatial and temporal scales. Further elaboration of Critical Habitat outcomes at spatial scales finer than range, over specified time frames, may be achieved through spatial population viability analysis linked with dynamic landscape modelling ...
Northern Abalone (Haliotis kamtschatkana)
Northern Abalone (Haliotis kamtschatkana)

... British Columbia every 3-5 years from 1978 to 2007. Since 1978, abalone densities have declined by 83% on the central coast and by 81% in the Queen Charlotte Islands (approximately 3 generations). The mean total abalone density declined from 2.40 to 0.40 abalone/m2 for the central coast between 1978 ...
Word - Fisheries and Oceans Canada
Word - Fisheries and Oceans Canada

... attributed to many factors, which include illegal harvest and low recruitment. It is unclear whether disease may have had a role in the decline of this species in the wild. Future threats may also include habitat loss due to developments in, on, and under the water, as well as previously unstudied i ...
namibian cheetah conservation strategy
namibian cheetah conservation strategy

... population is not isolated from the Botswanan population, and thus the population will always be effectively larger than any Namibian population estimate; and that over 95% of the world’s captive cheetahs are descended from wild-caught Namibian animals, and could be used for population replenishment ...
Atlantic Salmon Salmo salar
Atlantic Salmon Salmo salar

... This species requires rivers or streams that are generally clear, cool and well-oxygenated for reproduction and the first few years of rearing, but undertakes lengthy feeding migrations in the North Atlantic Ocean as older juveniles and adults. This population breeds in rivers from the southeast tip ...
Allee effects in biological invasions
Allee effects in biological invasions

... population that does not exceed this threshold will become extinct. Many studies consider only ÔstrongÕ Allee effects but the examples in Allee’s original work show clearly that the definition should also include ÔweakÕ Allee effects (Allee 1931, 1938, 1958; Fowler & Baker 1991; Stephens et al. 1999 ...
wolf and elk predator-prey dynamics in banff national park
wolf and elk predator-prey dynamics in banff national park

... In 1997 I began my contract with Parks Canada to study wolf and elk population dynamics in response to recommendations in the government task force, the Banff Bow Valley Study, and the new BNP management plan. Other cooperating agencies during this period included Alberta Environment Protection, Kan ...
long term study of competition between two co
long term study of competition between two co

... SAVOLAINEN and PURSIAINEN, 1995). The main reason is that P. leniusculus has either been introduced into plague-waters or the stocked specimens have been carriers of the plague. The shortage of long-term monitoring studies is particulary regrettable, as these are essential when new species are intro ...
The eco-geography of the brown shrimp Crangon crangon in Europe
The eco-geography of the brown shrimp Crangon crangon in Europe

... structure was studied by sequencing a 388 base pairs fragment of the cytochrome-c-oxidase I gene for 140 individuals from 25 locations across its distribution range. Divergence times between main phylogeographic groups were estimated using net nucleotide divergence and applying a molecular clock. Ge ...
chapter9
chapter9

... especially when forages become depleted or when adequate forage crops are not established. It is also likely that, as crawfish density increases beyond some optimum density, natural food resources become depleted. Under these conditions, production of highly nutritious invertebrates, important compo ...
Rangifer tarandus caribou By: Jennifer Renton
Rangifer tarandus caribou By: Jennifer Renton

... One woodland caribou population that has been intensively studied is the Slate Islands caribou (Slate Islands Provincial Park, Lake Superior, Ontario).The Slate Islands caribou population is an insular caribou population located approximately thirteen kilometers south of the northern shores of Lake ...
June X, 2006 - Wild Fish Conservancy
June X, 2006 - Wild Fish Conservancy

... measurement error in the data is likely relatively small. A high degree of measurement error would appear as random scatter rather than as a clear trend with respect to time, making it more likely that these data sets accurately reflect real underlying trends. The preponderance of the evidence from ...
The Influence of Interspecific Competition and Other Factors on the
The Influence of Interspecific Competition and Other Factors on the

... was chosen (by flipping a coin), and those Balanus which were touching or immediately surrounidingeach Chthamnaluswere carefully removed with a needle; the other portion was left untouched. In this way it was possible to measure the effect on the survival of Chthamalus both of intraspecific competit ...
namibian cheetah conservation strategy
namibian cheetah conservation strategy

... population is not isolated from the Botswanan population, and thus the population will always be effectively larger than any Namibian population estimate; and that over 95% of the world’s captive cheetahs are descended from wild-caught Namibian animals, and could be used for population replenishment ...
Harvesting of Flyingfish in the Eastern Caribbean - UNU-FTP
Harvesting of Flyingfish in the Eastern Caribbean - UNU-FTP

... The Caribbean Regional Fisheries Mechanism Secretariat (CRFM) was established in 2003 to further develop the Region’s institutional capacity in the fisheries sector. CRFM promotes the sustainable use of fisheries and aquaculture resources in and among its 18 Member States, by developing, managing an ...
northern abalone - Fisheries and Oceans Canada
northern abalone - Fisheries and Oceans Canada

... northern abalone in B.C.) to curtail the threat from illegal harvest and trafficking of northern abalone. Intended also to improve community confidence that reports will be acted upon, which will support development of Coast Watch programs. 2. Preventative enforcement through active patrols to enfor ...
6.4 Environmental Niche Analysis - Predicting potential occurrence
6.4 Environmental Niche Analysis - Predicting potential occurrence

... distribution of species (Soberon 2007). Species distribution models are one type of empirical model relating spatial observations of an organism to environmental predictor variables, using a variety of statistical techniques, from logistic regression to more complex computation approaches (Guisan an ...
Review of Seabird Demographic Rates and Density Dependence
Review of Seabird Demographic Rates and Density Dependence

... rates of sea ducks were largely lacking, with the exception of common eider. An estimate for age of recruitment was available for all of the seabird and sea duck species considered. There was considerably less information identified for the incidence of missed breeding and the rate of breeding dispe ...
Selection of Northern Yellowstone Elk by Gray Wolves and Hunters
Selection of Northern Yellowstone Elk by Gray Wolves and Hunters

... We compared selection of northern Yellowstone elk (Cervus elaphus) by hunters in the Gardiner Late Hunt and northern Yellowstone wolves (Canis lupus) with regard to sex, age, and impacts to recruitment. We compared harvest data from 1996–2001 with wolf-killed elk data from 1995–2001. We assessed the ...
New South Wales Commercial Kangaroo Harvest Management Plan
New South Wales Commercial Kangaroo Harvest Management Plan

... approve a wildlife trade management plan for a maximum of five years. The EPBC Act specifies that such approval must only be given if the Minister is satisfied that: a) the plan is consistent with the objects of Part 13A of the EPBC Act b) an assessment of the environmental impacts of the activities ...
new south wales - Office of Environment and Heritage
new south wales - Office of Environment and Heritage

... legislative provisions requiring the development and approval of wildlife trade management plans in order for permits to be issued for the commercial export of wildlife products. The EPBC Act states that the Commonwealth minister responsible for the environment may approve a wildlife trade managemen ...
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Maximum sustainable yield

In population ecology and economics, maximum sustainable yield or MSY is theoretically, the largest yield (or catch) that can be taken from a species' stock over an indefinite period. Fundamental to the notion of sustainable harvest, the concept of MSY aims to maintain the population size at the point of maximum growth rate by harvesting the individuals that would normally be added to the population, allowing the population to continue to be productive indefinitely. Under the assumption of logistic growth, resource limitation does not constrain individuals’ reproductive rates when populations are small, but because there are few individuals, the overall yield is small. At intermediate population densities, also represented by half the carrying capacity, individuals are able to breed to their maximum rate. At this point, called the maximum sustainable yield, there is a surplus of individuals that can be harvested because growth of the population is at its maximum point due to the large number of reproducing individuals. Above this point, density dependent factors increasingly limit breeding until the population reaches carrying capacity. At this point, there are no surplus individuals to be harvested and yield drops to zero. The maximum sustainable yield is usually higher than the optimum sustainable yield and maximum economic yield.MSY is extensively used for fisheries management. Unlike the logistic (Schaefer) model, MSY has been refined in most modern fisheries models and occurs at around 30% of the unexploited population size. This fraction differs among populations depending on the life history of the species and the age-specific selectivity of the fishing method.However, the approach has been widely criticized as ignoring several key factors involved in fisheries management and has led to the devastating collapse of many fisheries. As a simple calculation, it ignores the size and age of the animal being taken, its reproductive status, and it focuses solely on the species in question, ignoring the damage to the ecosystem caused by the designated level of exploitation and the issue of bycatch. Among conservation biologists it is widely regarded as dangerous and misused.
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