Maximum sustainable yield in fisheries

Maximum sustainable yield in fisheries

In population ecology and economics, maximum sustainable yield or MSY is, theoretically, the largest yield/catch that can be taken from a species' stock over an indefinite period. Under the assumption of logistic growth, the MSY will be exactly at half the carrying capacity of a species, as this is the stage at when population growth is highest. The maximum sustainable yield is usually higher than the optimum sustainable yield.

This logistic model of growth is produced by a population introduced to a new habitat or with very poor numbers going through a lag phase of slow growth at first. Once it reaches a foothold population it will go through a rapid growth rate that will start to level off once the species approaches carrying capacity. The idea of maximum sustained yield is to decrease population density to the point of highest growth rate possible. This changes the number of the population, but the new number can be maintained indefinitely, ideally.

MSY is extensively used for fisheries management. Unlike the logistic (Schaefer) model, MSY in most modern fisheries models 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.

Unfortunately errors in estimating the population dynamics of a species can lead to setting the maximum sustainable yield too high (or too low). An example of this was the New Zealand Orange roughy fishery. Early quotas were based on an assumption that the orange roughy had a fairly short lifespan and bred relatively quickly. However, it was later discovered that the orange roughy lived a long time and had bred slowly (~30 years). By this stage stocks had been largely depleted.

ee also

* Maximum sustainable yield
* Population dynamics of fisheries


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • 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… …   Wikipedia

  • Sustainable yield in fisheries — The sustainable yield of natural capital is the ecological yield that can be extracted without reducing the base of capital itself, i.e. the surplus required to maintain ecosystem services at the same or increasing level over time. This yield… …   Wikipedia

  • maximum sustainable yield — the average or maximum catch that can be removed under existing environmental conditions over an indefinite period without causing the stock to be depleted, assuming that removals and natural mortality are balanced by stable recruitment and… …   Dictionary of ichthyology

  • Optimum sustainable yield in fisheries — In population ecology and economics, optimum sustainable yield is the level of effort (LOE) that maximizes the difference between total revenue and total cost. Or, where marginal revenue equals marginal cost. This level of effort maximizes the… …   Wikipedia

  • Fisheries management — is today often referred to as a governmental system of management rules based on defined objectives and a mix of management means to implement the rules, which is put in place by a system of monitoring control and surveillance (MCS). Modern… …   Wikipedia

  • Fisheries glossary — This is a glossary of terms used in fisheries, fisheries management and fisheries science. A * Abundance is a measure of how many fish are in a population or a fishing ground. See relative abundance and absolute abundance.* Acoustic survey a… …   Wikipedia

  • Population dynamics of fisheries — A fishery is an area with an associated fish or aquatic population which is harvested for its commercial or recreational value. Fisheries can be wild or farmed. Population dynamics describes the ways in which a given population grows and shrinks… …   Wikipedia

  • Ocean fisheries — A fishery is an area with an associated fish or aquatic population which is harvested for its commercial value. Fisheries can be wild or farmed. Most of the world s wild fisheries are in the ocean. This article is an overview of ocean fisheries.… …   Wikipedia

  • Cod fisheries — Atlantic cod Pacific cod Cod f …   Wikipedia

  • Common Fisheries Policy — The Common Fisheries Policy (CFP) is the fisheries policy of the European Union (EU). It sets quotas for which member states are allowed to catch what amounts of each type of fish, as well as encouraging the fishing industry by various market… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”