Chapter 8 Flashcards
In Canada what percentage of wild fish is from inland sources?
Less than 4%
What are the two biggest threats to marine environments?
Over fishing
Habitat destruction
What are factors that can be used to assess the sustainability of marine fisheries?
- vulnerability of the species to fishing pressures
- The nature and extent of the bycatch
- The effect of fishing practices on the ecosystem
What type of fish are ,more susceptible to fishing pressures?
Fish like tuna, that are large, long-lived and slow to reproduce
Define bycatch
The incidental catching of non-target species when fishing for a particular species
What is the fishing gear with the most ecological impacts?
Bottom trawl
What is the fishing gear with the least ecological impacts?
Harpoon
What is the fishing gear that involves a large net that encircles the fish and is pulled together to enclose them. Has a relatively low bycatch impact
Purse Seine
What is the fishing gear that has a high impact on large pelagic species?
Pelagic longline
What is a type of net used in Atlantic Canada that hang vertically in the water and is secured to the sea floor. Problematic for ground fish bycatch?
Bottom gillnet
What are the metal baskets that are dragged along the sea floor to catch scallops?
Dredge
What is a net that hangs vertically in the water but does not touch the seafloor?
Midwater gillnet
What is a bottom secured line of bait hooks? Significant bycatch problem
Bottom longline
Farmed oysters are not very sustainable because of the amount of feed they require
False
An aquaculture technique known as off-bottom culture is used to farm mussels and clams.
True
Aquaculture is the most sustainable method of fish production.
False
To assess the sustainability of aquaculture both the type of fish feed and the location of the aquaculture facility need to be considered
True
A challenge associated with a land based closed-containment system of aquaculture is that this industry has to pay for externalized costs of production (e.g. waste disposal) that net-pen systems do not.
True
True
What are 2 very important factors used to assess the sustainability of aquaculture?
Use of marine resources in fish feed
Open ocean vs land based system
What is the most sustainable fish feed?
. Best sustainable fish choices include fish that rely on omnivorous diets (like freshwater tilapia which rely on plant-based diets) or filter feeding shellfish (like oysters, clams and mussels) that rely on naturally occurring plankton (tiny plants and animals) in the seawater.
What are some risks to netted pens in the ocean?
escaped farmed fish and their effects on wild fish populations
pollution and other impacts on habitats and ecosystems
What is MSC?
The Marine Stewardship Council
The MSC is a global non-profit organisation working with fisheries, seafood companies, scientists, conservation groups and the public to promote the best environmental choice in seafood
Define sustainable seafood.
Sustainable seafood can be defined as species that are caught or farmed in a way that ensures the long-term health and stability of that species, as well as the greater marine ecosystem
What are the principles that fisheries must meet to receive MSC accreditation?
- Sustainable fish stocks
- Minimizing environmental impacts
- Effective management
Name 5 accepted sustainable seafood
Arctic Char Pickerel Halibut Shellfish Spot prawns Albacore tuna cod sablefish snow crab lake whitefish rainbow trout salmon
Most of the global fish production that is not used directly for human food is processed and used as high-protein feed for livestock and aquaculture:
True
Aquaculture accounts for approximately ______ % of the total global fishery food supply.
50%
Which country dominates the global fisheries production?
China
The FAO estimate that almost _____% of fish stocks are currently being fished at biologically unsustainable levels.
30%
An ecosystem approach to managing fisheries only considers the target species.
False
The following is a device used to decrease the amount of bycatch in the fishing industry.
Turtle excluder device
A good way to assess the sustainability of wild caught fish is to examine the type of food that is consumed by the fish.
False
In Canada all farmed salmon is produced using a closed-containment system.
False
Which of the following is listed on the OceanWise Recommended Sustainable Seafood list?
a) Longline caught albacore tuna
b) Gillnet caught halibut
c) Dredged scallops
d) Closed-system farmed rainbow trout
e) Open-net farmed salmon
D - Closed-system farmed rainbow trout
The following fishing method is particularly damaging to the seafloor.
Bottom Trawl
The following fishing method causes little habitat damage but can cause high levels of bycatch.
Pelagic Longline
One of your readings in this Unit reported on the largest off-shore fish farm in the world (located in Panama). What fish is produced at this farm?
Cobia
Off-bottom culture is an aquaculture method used primarily for the production of shellfish.
True
Mangrove forest destruction is associated with the farming of what type of seafood?
Shrimp
Open net-pen aquaculture is used to produce farmed shellfish
False
