introduction to fisheries Flashcards
what is The importance of fish to human society
Fish = extremely nutritious – excellent source of
protein, minerals and essential fatty acids
- convenient for poorer members of the global community
- 800 million people suffer from chronic malnourishment
- population is expected to grow another 2
billion to reach 9.6 billion by 2050 - growing population
- Most fish pathogens are not harmful to humans
why is fish important for protein
Fish protein is a vital nutritional component in some
densely populated countries where total protein intake levels may be low
- A portion of 150 g fish can provide 50-60% of an adult’s daily protein requirement
- Globally, aquatic foods provide about 17% of animal
protein
why is fish important for Omega-3 fatty acids
- Evidence that Pliocene hominins (predate Homo erectus) ate aquatic animals including turtles, crocodiles, and fish (Braun et al. 2010)
- Aquatic animals are especially rich in PUFAs such as
docosahexaenoic acid (critical for human brain growth). - These aquatic animals may have provided critical
nutritional components that fuelled the evolution of later hominins
why is fish important for health and wealth
- Fisheries and aquaculture directly provide jobs to 59
million* people and supports the livelihoods of hundreds of millions. - Fish is especially important for developing countries
- Feeding our planet whilst safeguarding its natural
resources is a huge challenge
targeted fish caught in fisheries
- demersal (on or associated with seabed) e.g. flatfish, gadoids….
- pelagic fish
small e.g. herring, mackerel, anchoveta
large e.g. tuna, swordfish
what are fish mainly used for after being caught by fisheries
- directly consumed by humans
- non-food uses e.g. primarily fish oil and fish meal
what is fish meal
- most fish eat other fish in wild, need fish meals for fish in aquaculture too
- Produced from whole fish, fish remains or fish by-
products
3 Types of fishery
Artisanal - local, traditional, unrecognised
Recreational - sports fishing
Commercial/Industrial - for money
over that area of the sea do the largest fisheries occur
over the continental shelf (<200 m depth;
nutrient turnover in winter) or areas of upwelling of deep water
- Fisheries are associated with productivity - need areas with loads of light and nutrients
- temperate areas = most popular - have strong winter mixing + spring blooms
- tropical areas are increasing - due to more fishing effort
- upwelling areas are popular but go up and down e.g. El Niño in pacific have good and bad years of productivity
top 5 world fishing areas with most Fishery capture production (tonnes)
- Northwest pacific
- Western central pacific
- southeast pacific
- northeast atlantic
- eastern Indian Ocean
how do we estimate stock or population size of fisheries
look at fishery landings
- Inaccurate reports of landings will give imprecise stock estimates and management quotas, which can lead to overfishing
top 3 most valuable fisheries in UK
- shellfish
- demersal fish
- pelagic fish
what is the Exclusive Economic Zones (EEZ)
- Sea zone prescribed by the United Nations Convention on the Law of the Sea over
which a state has special rights regarding the
exploration and use of marine resources (fishery managment) - 200 nautical miles from coast
- Fisheries management is based on these zones
2 ways we ensure fish stay in the Exclusive Economic Zones (EEZ)
- Transboundary stocks - Stocks that range in the EEZs of at least two countries
- Straddling stocks - EEZ extend into the high seas
- Highly migratory species e.g. Tuna and tuna-like species present management challenges as migrate though different countries’ EEZs
problem with fishery management like EEZ Zones
doesn’t always work e.g. stock collapse of Cod and haddock - led to fishing moratorium in 1993 - they couldn’t replenish themselves
