Download Chapter 8 Fisheries Lessons

Canadian
Geography 1202
Fisheries – Chapter 8
1
Fisheries (Chapter 8)
 Renewable


resources:
Resources that are normally replaced or
replenished through natural processes
E.g.: fisheries, forestry, agriculture, wind
energy, etc.
Cod
Rose Blanche, Newfoundland
2
1. Introduction
 Fish
resources are a rich part of Canadian
history, culture and economics
Newfoundland Fishing Community
Bonavista Harbour after Cod Moratorium
3
Introduction
 Since
the 1980’s this renewable resource
is being threatened by overfishing,
pollution, and effects of climate change
 This endangers the way of life and
economy in these small communities
4
Introduction
 Canada’s
fisheries have led to the
development of hundreds of fishing
communities present along the shores of
the Atlantic and Pacific
Atlantic
Pacific
5
2. Marine Food Chain

Food Chain:
 A simple representation of the food
relationships between various species
within an ecosystem

Species are arranged from the simplest
organism to the top carnivores
Phytoplankton
Zooplankton
Capelin
Herring
Whale
6
Marine Food Chain
 Food


Web:
A complex representation of all the food
relationships present in an ecosystem
Contains a number of interconnecting
food chains
7
Marine Food Web
 An
example of a marine food web:
 Can
you identify a food chain from the
food web?
8
Marine Food Chain
 Here’s
a good example:

Salmon

Capelin

Zooplankton

Phytoplankton
9
Marine Food Chain
 Phytoplankton:


A microscopic, single-celled plant organism
that is the basis of the food chain
They live in shallow seawater and eat
decayed marine life
10
Phytoplankton Blooms
11
Phytoplankton Blooms
12
Marine Food Chain
 Zooplankton:


A microscopic, single-celled animal
organism that feeds on phytoplankton
They are a food for small fish like capelin
13
Marine Food Chain

A good illustration. Refer to p.132-133, text
Sun & Minerals
Phytoplankton
(Plant)
Marine Life Dies
& Decays
Large Predators
Zooplankton
(Seals, Killer whales)
(Animal)
Small Fish &
Crustaceans
(Caplin, Shellfish)
Large Fish
(Cod, Haddock)
14
3. Commercial Fish Habitats
 Habitat:

The environment or place in which an
organism lives
15
Commercial Fish Habitats
 Continental


Shelf:
A landmass that is submerged under 200m
or less of ocean water
See Fig. 8.3 pg. 133
16
Continental Shelf
17
Continental Shelf
18
Continental Shelves
19
Commercial Fish Habitats
 Fishing



Bank:
The water is less than 150m deep
Light and heat of the sun penetrate the
water, which helps small sea plants
phytoplankton and zooplankton to grow
Fish are attracted to these areas because
food is plentiful and they are great places
to spawn
20
Commercial Fish Habitats
 Atlantic
fishing banks:
21
22
Commercial Fish Habitats
 Trace
the Atlantic fishing banks (Fig 8.4)
on page 134
 Use



3 separate colours for:
Fishing banks
Continental shelf
Land
 Find
the 370 km fishing limit
23
4. Atlantic Offshore Fishery
A.




Boats travel great distances from the
shore (up to 370 km)
Remain at sea for 2 - 3 weeks before
returning to home port
They are equipped with the latest
technologies
They are long (20 to 50 m)
They have larger crews
24
Atlantic Offshore Fishery
A.


Boats return to large harbours near fish
processing plants
Many boats have their own fish
processing equipment on board
They are owned and operated by large
companies that catch, process and
market the fish
25
Atlantic Offshore Fishery
15% of fishers work in the offshore fishery
C. Offshore fishing accounts for 90% of the
total Atlantic catch
D. Offshore boats are able to withstand the
harsh ocean environment, therefore crews
can work year-round
E. Crews’ income is steady
F. Major species caught: cod, herring, Atlantic
salmon, scallops, lobster and crab
B.
26
Advantages of Working in Offshore
 Fishers
earn a good income
 There is a steady amount of work
 Modern boats are spacious and luxurious,
containing TV’s, DVD players, Computer,
etc.
 Those onboard are able to choose a
specialized task
27
Disadvantages of Working in
Offshore
 Fishers
have less independence because
they are employees – They do not own or
operate the boats they work on
 They are away from their homes and
families for long periods of time
 They may not like working with certain
crew members
28
Atlantic Offshore Fishery
G.
Trawlers:

They are the main type of fishing technique
used in Canada's Atlantic offshore fishing
fleet
Harvest traditional groundfish species such
as cod, haddock, flounder and hake

Trawler at Fort
Amherst, NL
Large Factory Trawler
29
Atlantic Offshore Fishery

Cone-shaped nets are towed along the
ocean bottom, allowing only the smaller fish
to escape
30
Advantages of Trawlers
 Catches
are often enormous, with up to 2
hours towing the net, and yielding up to
100 tons of fish
31
Disadvantages of Trawlers
 Bottom
trawling has already extinguished
as many as 10,000 species worldwide
 The heavy metal weights attached to nets
crush everything in their path leaving scars
for up to 4 km
 They destroy ancient deep water coral
systems, which provide food and shelter for
fish
Before
After
http://www.greenpeace.org.uk/MultimediaFiles/Live/Video/6768.mov
32
Disadvantages of Trawlers
 Only
16-72 % of the catch contains
desired fish; the rest of the captured sea
life (bycatch) suffocates and is thrown
back overboard
Discarded
Bycatch
33
 Read
Case Study: the Scotia Eagle (pg
138 – 139)
 1.
List characteristics that show you that
Jimmy is working on an offshore boat.
 2. List the advantages and disadvantages
according to Jimmy.
 3. Explain in detail how the otter trawler
works.
 4. How does the trawler net stay open
vertically and horizontally?
34

1. – size of the boat (47m)
 Boat can handle harsh environments
 Boat fishes far offshore (225km)
 Uses a trawler net
 Processing equipment on board
 Fisher work year round
 Higher and steady income
 Large crews (18 people)
 Latest technology – echo sounder and
freezer
 Long time at sea (couple of weeks at a
time)
35
 2.
Advantages
- Steady income
- Higher income
- Modern boat
Disadvantages
- Long time away from home/families
- Not being able to work with father or keep
up the family business
36
 3.
-
-
-
The net is set down with the weighted
rollers (Ground bobbins) rolling along the
ocean floor
Headline floaters hold the net open
Fish are scooped up and remain in the cod
end as the net is brought up to the boat
37
 4.
The net stays open horizontally because of
the otterboards.
The net stays open vertically because of the
weight of the ground bobbins and the light
weight of the headline floats allows them
to float, therefore holding up the top of the
net and keeping the entire net open.
38
5. Atlantic Inshore Fishery
A.




Boats:
They are smaller than 20m in length
Fish close to shore, returning to the
harbour before sunset
Crews are small, with only 3-5 people
Traditionally they are run by father and
sons or brother
39
Atlantic Inshore Fishery

80% of Atlantic fishermen were once
employed in the inshore fishery
 Inshore harvests include lobster, shrimp,
redfish, and halibut
 Very little technology used - maybe a depth
finder
40
Advantages of Inshore Fishery
to families on a regular basis –
usually home most nights
 Fishers have independence because they
are self employed
 They choose their own crew members –
mainly family
 Variety of tasks makes the work more
interesting
 Return
41
Disadvantages of Inshore Fishery
 Generally
fishers earn a low income,
which can be irregular
 Fishers often depend on government
subsidies such as Employment Insurance
 Quota levels are much lower compared to
large boats
 The number of working days is limited by
weather
42
Atlantic Inshore Fishery
B.



Lobster Fishing:
Lobsters are caught by inshore fishers
using traps set on the ocean floor, either
individually or in groups on a line
One or more funnel-shaped openings on
the trap allow the lobster to enter the trap
but prevent it from escaping
Most valuable seafood caught
43
Atlantic Inshore Fishery
 Traps
are set in waters of varying depths,
but usually near a rocky bottom, which
lobsters prefer
44
45
Offshore and Inshore Fisheries
 Create
a chart that compares these two
fisheries
46
6. Collapse of the Cod Fishery
In the 1960’s, huge factory freezer trawlers
started being used in the cod fishery
 The number of the trawlers fishing the
Atlantic increased as the demand for cod
increased worldwide
 Foreign fleets began fishing in the Atlantic
(Russia, Japan, Korea, Poland)

47
Collapse of the Cod Fishery

By 1970 over-fishing was becoming a serious
problem – it was estimated that the Atlantic
catch had risen to three times it’s traditional
level

In 1977, Canada extended its fishing limit to
370 km – since it was only 22 km – and now
had the right to control quotas, size, tonnage,
seasons, and equipment within this limit
48
Collapse of the Cod Fishery

Despite these efforts, it was clear by the mid
1980’s that the cod stocks were not
rebounding to their traditional sizes

In 1994 the cod fishery had collapsed and an
indefinite moratorium was put in place

This ended five centuries of economic activity
that had supported thousands of people in
Newfoundland – devastating entire
communities whose life had been organized
around the cod fishery
49
Other Major Factors Leading to the
Collapse
 Quotas
were too high and the size of the
breeding stocks were over estimated
 The
use of trawler nets damaged plant
and animal life, and therefore disrupted
the food chain that supported the cod
stocks
50
Other Major Factors Leading to the
Collapse
 Changes
in the flow of the Labrador
Current may have caused the fish to
migrate elsewhere
 The
growing number of seals may have
further depleted an already depleted stock
51
7. Pacific Fishery
 A Day
in the Life of a Pacific Fisher!!!
52
Pacific Fishery
 The
Pacific commercial fishery is
relatively young compared to that in
Atlantic Canada
53
Pacific Fishery
 Salmon
is the most important catch in
the Pacific coast fishery and the most
unique
 Salmon accounts for almost half of
the total value of the fish caught on
the west coast
54
Pacific Fishery
 There
are five varieties of salmon caught chum, pink, chinook, coho and sockeye
55
Pacific Fishery
56
Pacific Fishery
57
Life cycle of the Pacific salmon
 See
Fig 8.14 on pg. 146 and HANDOUT!
58
59
Pacific Fishery
A.
Gill Nets:

A net with a specific mesh size is used to
ensnare fish of a specific matching size
Fish can swim part-way but not all the way
through the net. When it tries to back out, it
becomes snagged on its gill covers
Used on inshore salmon migration routes
near the mouth of salmon-spawning
streams


60
Gill Net
61
Pacific Fishery
B.
Purse Seines Nets:

A net with floats at the top and lead weights
at the bottom
 The purse line at the bottom of the net is
then drawn in, closing it off and trapping the
fish
 The net encircles schools of fish at or near
the surface.
 Used on inshore salmon migration routes
near the mouth of salmon-spawning
streams
62
Purse Seines Nets
See Fig. 8.15 on pg. 147
63
Pacific Fishery
C.




Troll Lines:
Trollers are small fishing vessels
operated by one or two people
Fish are caught with a number of lines
with baited hooks or artificial lures
It is the least efficient commercial fishing
method in terms of intercepting fish
Troll-caught salmon are high quality
64
Troll Lines
65
8. Salmon Habitat under Attack

Salmon habitat – range from spawning
beds in rivers to vast oceans
66
Salmon Habitat under Attack
A.


Logging
Has the greatest impact on the salmon
habitat because in B.C. 40% of all
harvested logs are hauled up the Fraser
River
Cutting forests on mountain slopes
increases soil erosion which causes mud
and silt to cover the gravel stream beds –
destroying valuable spawning grounds
67
Salmon Habitat under Attack
B.

Draining estuary wetlands
Draining and landfilling these marshes
reduces the flow of the nutrients and
food salmon require for growth
68
Salmon Habitat under Attack
C.


Pollution
Herbicides and pesticides used for
agriculture in the Fraser Valley enter
water system
Organic wastes from sewage and meat
packing plants, and pulp and saw mills
decompose – reducing the amount of
oxygen in the water – killing fish
69
Salmon Habitat under Attack
D.


Dams
River dams obstruct salmon migration
Now – fish ladders used to allow salmon
to return to their spawning grounds
70
Salmon Habitat under Attack
E.


River Diversions
Water is diverted for industry and
irrigation at the same time juvenile
salmon migrate downstream
This results in low water levels and
warmer water temperatures dooming
salmon to an early death
71
 1.
Describe the habitats required by
the Pacific salmon during its life cycle.
 2.
What effect does logging,
draining estuaries, and dams have
on the salmon's life cycle?
72
1.
 Cool,
nutrient and oxygen rich rivers and
streams for egg incubation, salmon growth
and clear stream routes for migration.
 Estuaries that have mixture of salt and
freshwater, with enough oxygen and
nutrients
 Clear saltwater with enough food sources
73
2.
Logging:
 can bring soil (from erosion) into the streams –
which harm spawning areas
 Driving and storing logs can block migration
routes to and from spawning grounds
Draining Estuaries:
 Removing water or filling these estuaries, it
prevents adult salmon from migrating to
spawning beds, and smolts can no longer adapt
to salt water in the estuaries.
Dams:
 Block migrations routes up to spawning beds
74
9. Crisis in the Salmon Fishery
A.
B.
New technology has meant that
commercial fleets can catch in hours
what they used to take days to catch
Deep sea drift nets “ghostnets” used to
catch tuna and other large fish scoop up
everything in their path including salmon
75
Crisis in the Salmon Fishery
C.
Poor management of the resource has
added to the problem of overfishing. The
collapse of the Pacific Salmon Treaty in
1995 between Canada and the United
States resulted in quotas being abused
D.
Global warming has contributed to the
problem by increasing the ocean
temperature – causing an explosion of
mackerel populations, which feed on
salmon
76
Crisis in the Salmon Fishery
E.
Finally the number of sport fishers has
increased – meaning more fish are being
caught than ever before
77
Crisis in the Salmon Fishery
 Solutions
to the Problem:
 Reduction
of the commercial salmon
fishing fleet by 50%
 Certain
areas like the Fraser River would
be shut down to hopefully replenish
themselves
78
10. Aquaculture
 The
raising of marine life in a controlled
environment
 As known as fish farming
 Fish and other marine species are bred
and raises fish in tanks, ponds and
reservoirs
79
Aquaculture
 Fish
are fed regularly and are safe from
their natural enemies – thus maturing
rapidly
 Diseases and parasites outbreaks often
occur because of high population densities
found in the fish farms
Sea lice, like the ones
attached to these smolts,
are a major problem in the
salmon farming industry
80
Aquaculture
 Salmon,
trout, mussels and oysters are
good examples of farmed species
 Aquaculture is considered a growth
industry in Canada
81
Aquaculture Case Study
 1.
It can produce large volumes of healthy
mature fish in a short period of time.
 Since
overfishing is depleting natural
stocks, aquaculture might be the only way
to meet the growing demand for fish
82
 2.
For more than 10 years Canada has
experienced great success in aquaculture,
and it is expected that we will continue to
be successful in this industry
 We have the resources to sustain this
industry
 3.
Overfishing
83
 4.
Canada is well suited because we have
large areas with abundant amounts of
freshwater for constructing reservoirs,
ponds, tanks, ect.
 5.
Salmon is a high-priced fish, after they
started farming fish it added $100 million/yr,
and jobs were created.
84
 6.
The sheltered bays and inlets make
great breeding sites, the strong tides carry
away fish waste and leftover food that
would otherwise pollute, and there are
ideal water temperatures
 7.
most of the ideal sites for raising salmon
are already taken up by other fish farms,
plus establishing a farm is expensive, and
diseases and parasites
85
11. The Freshwater Fishery
 Canada
has a major freshwater fishery
with the Great Lakes being the central
area
 Canadian lakes contain over 180 different
species – perch, pickerel, trout, and bass,
and they employ over 9000 crew members
and fish processing workers
 Sport fishing is also a major economic
activity for many communities
86
The Freshwater Fishery
Northern
Pike
Smallmouth
Bass
Walleye
87
Devil’s Lake - Ontario
88
Devil’s Lake - Ontario
89
"Only after the last tree has been cut down,
Only after the last river has been poisoned,
Only after the last fish has been caught,
Only then will you realize that money cannot
be eaten"
- Cree Proverb
90