This document discusses overexploitation of wild fish stocks. It begins by explaining different types of overfishing including growth overfishing, recruitment overfishing, and ecosystem overfishing. It then provides examples of overexploited fish stocks in India like oil sardine, Indian mackerel, and Bombay duck. Studies on fish stock status in Karnataka and Kerala are mentioned, identifying certain species as depleted or declining. The document concludes by discussing the negative impacts of overexploitation, and some potential solutions like establishing marine protected areas and implementing fishing quotas.

1. OVEREXPLOITATION
OF WILD STOCKS
Presented BY:
PARUL
Dept: FRM
college of fisheries science, hisar
(CCSAU)

2.  Nutritional security
 Livelihood
 Wealth

3. Overfishing is a form
of overexploitation where fish stocks are
reduced to below acceptable levels.
Overfishing can occur in water bodies of
any size, such as ponds, rivers, lakes or
oceans, and can result in resource
depletion , reduced biological growth
rates and low biomass levels.
Sustained overfishing can lead to critical
depensation , where the fish population is
no longer able to sustain itself

4. Under exploited
Moderately exploited
Fully
exploited
Over exploited
depleted

5. Growth overfishing
occurs when fish are harvested at an
average size that is smaller than the size
that would produce the maximum yield per
recruit.
Malthusian overfishing
An expression that was coined to describe
a situation that may occur when fishing
levels are too intense for a fishery to be
sustainable.

6.  Economy overfishing
A level of fish harvesting that is higher than that of
economic efficiency; harvesting more fish than
necessary to have maximum profits for the fishery.
 Recruitment overfishing
The rate of fishing above which the
recruitment to the exploitable stock becomes
significantly reduced.
This is characterized by a greatly reduced
spawning stock, a decreasing proportion of
older fish in the catch, and generally very low
recruitment year after year

7. Ecosystem overfishing
Ecosystem overfishing occurs when the
balance of the ecosystem is alerted by
overfishing.
The ability of a fishery to recover from
overfishing depends on whether the
ecosystem’s conditions are suitable for the
recovery.

8.  Has a coastline of 8,129 km
 Exclusive Economic Zone (EEZ) - 2.02
million sq km
 comprising 0.86 million sq km on the East
coast,
 0.56 million sq km in the West coast and
 0.60 million sq km around the Andaman
and Nicobar islands

10. Direct effect
 Growth Overfishing and Recruitment
Overfishing
 Physical disturbance by fishing gears

11. Indirect effects
 Ghost fishing
 Trophic cascading effects
 Food web-competetion

12. Stock Classification Recent average catch in
historical maximum (%)
Abundant > 70
Less abundant 50-69
Declining 11-49
Depleted 6-10
Collapsed < 5

14.  Exponential growth in human population
 Lack of Marine Protected Areas(1.6%)
 Pirate fishing(20% in world)
 Massive by catch (yellow fin tuna)
 Subsides
 Expansion of trade of ornamental fishes

15. Species Means of exploitation
Oil sardine- boat seine, gill net
Anchovies- gill net , bag net ,shore seines,
Mackerel dug out canoes, purse seine, trawler
Tunas pole and line, hook and line, troll lines,
drift gill net
Peruvian anchovy Purse seine
Bombay duck -bag net called dol net

17. The maximum sustainable yield (MSY)
was 1,107 tonnes which was lower than
the average annual catch (1,296 tonnes)
Indicating over exploitation.(2011)

18. Karnataka
55% were in declining status
Metapenaeus monoceros was identified
as a depleted stock.
Metapenaeus dobsonii and
Pampus argenteus were also close to
this depleted status

19. kerela
47% were in declining status.
 Lactarius lactarius
 Pampus argenteus
were identified as depleted stocks

20. Species Status
White fish Declining
Ribbon fish, flate fish, elasmobranch,
mullet
Less abundant
Flying fish Depleted
Unicorn cod Collapsed

22. Peruvian anchovy
 Atlantic cod is one the most severely
depleted fish stocks in the northern
hemisphere

23. Depletion of some stocks of blue fin
results to listed on Convention on
International Trade in Endangered
Species of Wild Fauna and Flora
(CITES)
Skipjack tuna -moderately exploited in
some oceans
Big eye and yellow fin tuna -fully or
over-exploited

24.  Reduces fish production
 Decreased food security
 Put a number of threatened and
endangered species at risk for extinction.
 Over exploitation of the coastal resources
up to 50m depth has been leading to
reduction of catch per unit effort

25.  Setting up marine reserves or marine
protected areas (MPAs)
 Establishing fishing quotas
 Restoring the populations of endangered
species
 Policies or legislations
 Fisheries agreement

26. Technical measures
1.Gear modifications that improve
selectivity
2. Size selectivity of target species
3. Non-target species selectivity(TEDs,
circle hooks)

28. 4. Spatial and temporal controls on
fishing
Ecosystem manipulation
 Habitat modifications
 Population manipulation

30. Thank You