Topic 12: Methods Of Reducing The Environmental Impacts Of Fishing

Question 1

4 ways the environmental impacts can be reduced

Answer 1

Catch quotas
Fishing equipment design and use
Restricting fishing Effort
Restricting fishing methods

Question 2

What is the purpose of a catch quota?

Answer 2

To set a limit of the total weight of fish that can be landed
It might be divided up between all fishing boats in a fleet

Question 3

When do catch quotas work best?

Answer 3

When fish are found in single-species shoals
Fishing will stop if the quota for that species is reached

Question 4

When do catch Quito’s not work/are less effective?

Answer 4

In mixed fisheries when different fish are caught in the same net
If the catch quota for one species has been reached, surplus may be returned to the ocean whilst fishing for the other species continues
The surplus are likely o be returned dead or injured

Question 5

Give 9 ways fishing equipment designs and uses can be changed to reduce the environmental impacts of fishing

Answer 5

Mesh size
Mesh design
Escape panels acoustic deterrent devices
Hook shape
Decoys
Sinkers
Night fishing
Biodegradable/radiotracked equipment

Question 6

How can mesh size be altered to reduce the environmental impacts of fishing?

Answer 6

They can be set so that fish below a certain size can escape

Question 7

How can hook shape be altered to reduce the environmental impacts of fishing?

Answer 7

Longline hooks have curved points
Still catch tuna but less likely to catch albatrosses

Question 8

Escape panels

Answer 8

Turtle exclusion devices
Large spring loaded escape panels in the nets that allow turtles to escape

Question 9

Acoustic deterrent devices

Answer 9

Also known as ‘dolphin pingers’
Produce high frequency sounds that warn dolphins about the presents of the net

Question 10

Decoys

Answer 10

They attract and distract birds so they dont get caught on longline hooks

Question 11

Sinkers

Answer 11

Weights attached to pelagic longlines
They hold hooks down in the water so they still catch fish but not albatrosses

Question 12

Night fishing

Answer 12

Using longlines at night when birds aren’t feeding

Question 13

Biodegradable and radio tracked equipment

Answer 13

Reduces ghost fishing
Traps for crabs and lobsters, if they are held together by biodegradable rope, will fall apart if lost so wont continue to catch organisms
In the USA traps have radio-transmitters that activate if the traps are lost so they can be recovered

Question 14

How might the fishing effort be restricted in order to reduce the environmental impacts of fishing?

Answer 14

In some areas of the UK there are limits of the size and power of fishing boats, and no of days they can spend fishing
Where the number of fishing boats is so large that overfishing is unavoidable, boat owners may receive compensation for their boats to be decommissioned

Question 15

9 ways fishing methods are/can be restricted

Answer 15

Ban drifts nets
Bans on demersal trawling
No take zones
Turtle bycatch
Closed-seasons
Minimum and maximum catchable size
Protected individuals
Captive rearing and release

Question 16

Where might demersal trawling be banned?

Answer 16

In an area where the seabed ecosystem is particularly sensetive or important
E.g. it is banned of the NW coast of Scotland where there are deep water coral reefs

Question 17

No take zones

Answer 17

Areas where fishing and other activities that exploit wildlife or damage habitats are not permitted
Protects breeding populations and allows them to colonise other areas where populations have bed reduced by fishing
The communities of species that live within the zone can recover because damaging activities are stopped

Question 18

How can turtle bycatch be reduced?

Answer 18

By reducing the time the net is towed especially in tropical fishing areas
Less time caught in the net means less chance of drowning

Question 19

Closed seasons

Answer 19

Ban on fishing for part of the year
Allows fish to grow
Is ideal for breeding seasons to help sustain future generations

Question 20

Minimum catchable size

Answer 20

Banning the capture of small fish
Allow they to grow larger and live lng enough to breed

Question 21

Maximum catchable size

Answer 21

Protecting large individuals to make sure there is a surviving population of breeding adults

Question 22

Captive rearing and release, or ‘population seeding’

Answer 22

Wild populations of some species may be increased by releasing individuals raised in captivity
Most species spend their first few weeks drifting in plankton before settling on seabed and colonising habitats- releasing captive raised species increased chances of survival in this period