Sustainable fisheriesSpec 4.7.5.3
In short
Sustainable fisheries keep fish stocks at a level where breeding continues, so that species do not disappear from some areas. Controlling net size helps because a larger mesh lets small, young fish escape, survive and breed. Fishing quotas limit how much fish can be caught, so enough fish are left to breed and stocks recover.
Fish stocks in the oceans are declining. It is important to maintain fish stocks at a level where breeding continues or certain species may disappear altogether in some areas.
| Method | How it helps |
|---|
| Control of net size | A larger mesh lets small, young fish escape. They survive, grow and breed |
|---|
| Fishing quotas | A limit on how much fish can be caught, so enough fish are left to breed and stocks recover |
|---|
These techniques promote recovery of fish stocks and conserve them at a sustainable level.
Exam tip:Link both methods to breeding: they leave enough fish to reproduce, so the population is maintained.
Written and checked against the AQA GCSE Biology (8461) specification · Updated October 2026
Frequently asked questions
What threatens food security?
Food security, having enough food to feed a population, is threatened by an increasing birth rate, changing diets in developed countries that mean scarce food is transported around the world, new pests and pathogens, environmental changes such as rains failing, the cost of agricultural inputs, and conflicts that affect the availability of water or food.
How does intensive farming increase food production?
Intensive farming increases the efficiency of food production by restricting energy transfer from food animals to the environment. The animals' movement is limited and the temperature of their surroundings is controlled, so they transfer less energy to their surroundings and more of the energy from their food is used for growth. Some are also fed high protein foods.
How can fishing be made sustainable?
Fishing can be made sustainable by controlling net size and by fishing quotas. A larger mesh lets small, young fish escape, so they survive, grow and breed. Quotas limit how much fish can be caught, so enough fish are left to breed and stocks recover. Both keep fish stocks at a level where breeding continues.
All 4 questions on Food production
