Overfishing happens when aquatic animals are removed faster than their populations can naturally replenish. This lesson introduces the concept, explains how fisheries can be depleted, and distinguishes three recognized biological types of overfishing.
Overfishing is the removal of fish and other aquatic animals from a body of water at a rate greater than the population can replace through reproduction and growth. The result is that a species becomes increasingly underpopulated in that area. It can occur in ponds, wetlands, rivers, lakes, seas, and oceans—not only in large commercial fisheries.
All flashcards
What is overfishing?
It is the removal of aquatic animals at a rate greater than their populations can naturally replenish, causing populations to become depleted.
What is a recruit in fisheries management?
An individual that reaches maturity or enters the size or age range managed by a fishery.
What is growth overfishing?
It occurs when fish are harvested at an average size smaller than the size that would produce the greatest yield per recruit.
What is recruitment overfishing?
It happens when the mature spawning population is too depleted to produce enough offspring to replenish the stock.
How does ecosystem overfishing change a community?
It alters the balance among species, such as when declines in large predators allow smaller forage fish to become more abundant.
Quiz questions
In one bioeconomic framework, what harvest level is the benchmark for avoiding economic overfishing?Answer: The level associated with maximum economic yield.
What does a harvest control rule link to predicted fish-stock status?Answer: Harvest rates or management strategies.
Why can open-access fish stocks be vulnerable to a tragedy of the commons?Answer: Fishers may increase catches to avoid others taking the fish first.
What rights do individual transferable quotas assign to fishers?Answer: Rights to a defined percentage of the total allowable catch.
What does fishing down the food web describe?Answer: A shift in fishing toward smaller fish and lower food-web levels.
Based on the Wikipedia article Overfishing, licensed CC BY-SA 4.0. Adapted into a summary, flashcards and quizzes.