Lecture 16: Imperiled and extinct fishes

Fish Conservation and
Management
CONS 486
Imperiled and extinct fishes
You win some, you lose some!
Chapter 11 Ross
Topics
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Legislation and protection
Extinctions: examples and common causes
Extirpated: species/populations
Endangered and threatened: species/populations
– Including (you guessed it…) SALMON!
Major theme: Linking science to
conservation & management
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Physiology
Behaviour
Population ecology
Ecosystem ecology
Habitat data
(limnology,
oceanography)
• Life history
• Protecting
populations &
habitats
• Restoring
populations &
habitats
Basic science
Applied
science
Conservation
Management
• Fisheries
exploitation data
• Applied life history
data
• Human
dimensions: socioeconomic data
• Harvest regulations
• Managing fisheries
& habitats
Federal Legislative frameworks
• Fisheries and Oceans Canada (DFO) has legal
responsibilities under several legislative frameworks,
including:
– Oceans Act
– Canadian Environmental Assessment Act (CEAA)
– Species At Risk Act (SARA)
– Fisheries Act
• All geared toward promoting the effective management
and sustainability of freshwater & marine ecosystems and
biota
Federal Legislative frameworks
• Oceans Act:
– Relates to the exploitation, management, and
conservation of marine resources
– Estuaries, coasts, oceans, MPAs
• Canadian Environmental Assessment Act:
– Requires federal departments to conduct environmental
assessments for proposed projects where the federal
government is the proponent (or funder)
Protection of imperiled species
• COSEWIC (Committee on the Status of Endangered Wildlife in
Canada)
– Assesses risk status of wildlife in Canada
• SARA (Species At Risk Act) is federal legislation that can be applied
following a COSEWIC endangered listing
– SARA requires biological information AND societal/economic info
before a decision is reached
– Provides legal protection of wildlife and conservation of biological
diversity
Canada’s Fisheries Act
• Purpose: Provides the legal framework for regulating fish, fisheries
and fish habitat
– responsible for sea, coastal and inland fisheries
• Authority to manage fish habitat
– But no control over habitats which fall under provincial
jurisdiction
• Habitat protection provisions:
1. Fish passage
2. In-stream flow needs of fish
3. Destruction of fish by any means other than fishing
4. Destruction of fish habitat
• Revised fisheries act applies habitat provisions only to fish that are
considered part of a fishery, support a fishery, or are socially
important
• The habitats of most freshwater fish species in Canada are not
protected as they once were,
– Includes the majority of threatened and endangered fishes which
tend not to be economically important (any longer!)
Imperilment and extinction
• Human activities have lead to the extinction of > 40
species/subspecies in North America
– Most had restricted distributions
– Many more are imperiled (extirpated, endangered,
threatened)
Extinction ‘hot-spots’
• Many species from Great Lakes
– Overfishing, invasive species, habitat degradation
• Large group from American Southwest
– Water withdrawals, agriculture, habitat degradation
• COSEWIC 2014 lists ~700 species as extinct, extirpated, endangered,
threatened, or of special concern
• 388 vertebrates
– 94 freshwater fish (out of ~230 total resident freshwater species
in Canada; ~90 spp. in B.C.)
– 64 marine fish
– 76 mammals, 85 birds, 69 herps
• 34 molluscs!
• 55 arthropods
• The rest are lichens, mosses, & vascular plants
COSEWIC 2014: Extinctions in Canada
• 6 freshwater species listed as extinct
– Deepwater cisco, Banff longnose dace, Lake Ontario kiyi, blue
walleye & two Hadley Lake threespine stickleback
• Lake Ontario population of Atlantic Salmon
– Gone since 1898!
– Habitat destruction and over-exploitation
– Original strain is gone, re-introduction is not possible… but other
strains introduced!
Deepwater cisco: Extinct
• Overharvested in Great Lakes during early to mid
1900s using deep water gill nets
– Competition from invasive alewife/smelt and
predation by invasive sea lamprey pushed
them over the brink
• No refuges available
– Need really deep water; no areas available
outside the Great Lakes
Deepwater cisco (Coregonus johannae)
6 cisco species have declined in Great Lakes
– Overfishing (after sea lamprey affected lake trout
populations)
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Bloater (Coregonus hoyi) was the only cisco species that
remained fairly widespread due to small size (~37 cm)
– Then it became targeted by fisheries
– Now extirpated from Lake Ontario…
Banff longnose dace: Extinct (1987)
• Tiny subspecies of Eastern longnose dace
• Restricted to small marsh fed by hot springs in Banff
National Park
– Chlorine pollution
– Mosquitofish introduced in 1920s!
– Guppies and mollies also introduced…
• Exotics reproduced year-round
– Out-competed the dace for food and preyed on eggs
• Remaining few hybridized with Eastern longnose
– Banff subspecies' unique genetic structure was irreversibly
mixed
Banff longnose dace (Rhinichthys cataractae smithi)
Lake Ontario Kiyi (Coregonus kiyi)
• Last recorded in 1964
• Commercial overexploitation and predation, competition
by exotics
• Two subspecies:
• Upper Great Lakes Kiyi: special concern
• Lake Ontario Kiyi: extinct
Real Blue walleye
‘blue’ form of yellow walleye
Blue walleye (Stizostedion vitreum glaucum): Extinct
• Important commercial & sport fish in Great Lakes
– Looks similar to blue colouration of common yellow walleye
(Stizostedion vitreum vitreum)
• Lived in Lakes Ontario and Erie
– Last confirmed specimen taken from Lake Erie in 1965
• Common until the 1950s when the population declined dramatically
from overfishing and…
– Pollution and eutrophication
– Predation from introduced rainbow smelt
Three-spine sticklebacks
• Common throughout temperate coastal marine and fresh waters in
northern hemisphere
• Found in B.C. lakes and streams
• Many water bodies contain only a single stickleback species, but pairs
of species have evolved independently in a few small lakes that are <
12000 years old
• No more than two species occur in any one lake, one has evolved to
be limnetic, the other benthic
• Evolution seems to have occurred independently among lakes
• Some of the ‘newest’ fish species we are aware of
Benthic/littoral
Limnetic/pelagic
Dolph Schulter UBC
Three-spine stickleback pairs in B.C.
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Hadley Lake species pair: Extinct
– Known only from Hadley Lake, Lasqueti Island, B.C.
– Extinction due to introduced brown bullhead
• Enos Lake species pair: Endangered
– Restricted to a single, small lake on Vancouver Island
– Experiencing severe decline due habitat quality and invasives
– Species pair has collapsed into a hybrid swarm
• Paxton Lake species pair: Endangered
Benthic/littoral
– Impacted by habitat loss and/or degradation
– At risk from exotic species
• Vananda Creek species pair: Endangered
Limnetic
– Impacted by habitat loss and/or degradation from human
disturbance
– At risk from exotic species
Photo: Todd Hatfield
Many fish species from American SW are extinct
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Occurred in small, isolated, disconnected habitats
– Few refuges or recolonization areas
Altered flow and temperatures from water withdrawals
Devils Hole only habitat for one species of pup fish aka ‘the pool
fish’!
– One of most isolated fish habitats in world
Devil’s Hole
Pup fish (pool fish)
Pup fish (pool fish)
Not dead yet: Miller Lake Lamprey (Lampetra minima)
• World’s smallest lamprey (~ 10 cm)… cute right?
– PARASITIC!
• Chemical treatment of Miller Lake, Oregon to remove to protect
introduced trout
– Considered extinct in 1958… wrong!
• Adult lamprey collected in the Williamson River in 1992
• Unidentified lamprey collected in Miller Creek, the outflow stream of
Miller Lake in 1996
• Later surveys reconfirmed extirpation in Miller Lake but identified
several subpopulations outside Miller Lake sub-basin
Not Dead Yet: June sucker (Chasmistes liorus)
• Endemic to Utah Lake and Provo River, Utah, where it is now under protection
• Once considered extinct, now listed as critically endangered, < 300 fish in some yrs
• Result of predation on its young by introduced species (carp and walleye), pollution,
drought, alteration of water flow, and loss of native vegetation
• Current conservation measures – transplanted some to Red Butte Reservoir, and
use that as brood stock to raise fish in Springville Utah fish hatchery. After the June
sucker grow to a certain size, they are released into Utah Lake and the reservoir to
help build the population
• Example of how hatcheries and reservoirs were used in a conservation sense to
bring the wild lake population back from the brink.
Rose 2005 Fisheries
Common threads of imperilment
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HUMANS!
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Usually no single factor responsible
– Overharvest plus introduced species
– Habitat destruction plus introduced species
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Habitat size is not always the key issue
– E.g., pup fish vs ciscos
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Habitat interconnectedness is key because it influences…
– Number of refuge habitats
– Extent of recolonization areas
Fish extirpated from Canada
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3 species:
– Paddlefish
– Gravel chub
– One stock of striped bass (St Lawrence R)
– All exist still in US
Striped bass are a conservation success story in U.S.
– Other populations still considered endangered in Canada
– Found in NB, NS, Atlantic Ocean
Paddlefish (Polyodon spathula): Extirpated
• Ancient species harvested for its eggs
• Grow to 2 m and weigh over 70 kg
• Paddlefish can live for at least 30 years
– Individuals are slow to mature (7 years!)
• Paddlefish live in slow-moving areas of large rivers & lakes
– Migrate to large, fast flowing rivers with gravel bottoms where
eggs are protected and well oxygenated during development
• Paddlefish range in Mississippi River system
• Small commercial fishery still exists in some states
– Long time to maturity put it at risk
• Declines across entire range
– Loss of breeding habitat and over-fishing, dam construction
blocking spawning sites, channelization, water drawoff, and
pollution
• In Canada: last reported about 80 years ago in Lakes Huron and Erie
Gravel chub (Hybopsis x-punctata) : Extirpated
• Extirpated from Thames River in southwestern Ontario ~(1958): now
patchily distributed in East/Central U.S.
• Prefers clear, moderately-flowing streams with gravel bottom
– Hunts for food in the hollows beneath rocks
• Decline due to siltation and sedimentation of Thames River from
farmland runoff
~ 8 cm length
Striped Bass (Morone saxatilis): Extirpated (sort of)
• St. Lawrence estuary population disappeared by 1968 due to
recreational harvest, bycatch & illegal fishing
• Still occur in Bay of Fundy and Gulf of St. Lawrence
– Populations listed as threatened
• Occurs naturally along the US eastern coast
• US populations were near extirpation due to overharvest
– Recovered in recent years – will discuss in next lecture!
Fish that threatened/endangered in Canada
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55 species/stocks endangered
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40 threatened
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19 endangered in B.C.:
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8 stickleback species & pairs, nooksack dace, speckled dace,
Morrison Creek lamprey, 3 white sturgeon pops
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2 eulachon populations, interior Fraser coho, Cultus sockeye,
Sakinaw sockeye
6 threatened in B.C.:
– Umatilla dace, Vancouver lamprey, Cultus Lake Pygmy Sculpin,
Lower Fraser white sturgeon, Salish sucker, Okanagon Chinook
Cultus Lake pygmy sculpin
• Listed as threatened by COSEWIC
– ~5 cm long
– Only found in Cultus Lake, B.C.!
• Limited range and isolated
• Vulnerable to habitat changes
– E.g., Eutrophication and human activities
Sylvia Letay, BCMOE
Salish sucker and Nooksack dace
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Salish sucker threatened (COSEWIC)
Nooksack dace endangered (COSEWIC)
Affected by forestry and habitat development
Only occur in a few streams in southern Fraser Valley
– However, these species extend into Washington state
Salish sucker
Nooksack dace
Mike Pearson
Mike Pearson
• Morrison Creek Lamprey (Lampetra richardsoni var. marifuga) is a
rare form of the widely distributed Western Brook Lamprey:
endangered
• Ranges in size between 10-15cm
• Lives exclusively in Morrison Creek
– A tributary to the Puntledge River in Courtenay BC
• Main threat is urban development
Morrison Creek Lamprey
Morrison Creek Lamprey
White Sturgeon (Acipenser transmontanus)
• Adults eat live and dead fish, invertebrates, plants and are truly
opportunistic omnivores
• Adult white sturgeon can grow up to 6 m in length and weigh up to 800 kg!
• Matures 5-11 years
• 6 populations in Fraser, Nechako, and Columbia Rivers each suffering at
least a 50% decline: endangered or threatened
• Habitat degradation and loss through dams, impoundments, channelization,
pollution, illegal fishing and incidental catches
• Columbia populations
at risk of extirpation
• Upper Columbia River
basin population
~1,000 adults
Cultus Lake sockeye salmon
• One of the three salmon
populations listed as
endangered
• Overfishing, freshwater
habitat destruction are
factors
Status of anadromous salmonids in BC/Yukon (as of 1996!)
- of the 9,663 anadromous salmonid stocks, only 5,491 (57%) had reliable information AND
information is clearly out of date but nothing more modern has been assembled!!
-142 extinctions (2%) which is pretty low - but why?
- habitat degradation, primarily through loss of connectivity (urbanization, hydropower
development)
Lost Streams of the Lower Mainland
• lost streams = lost salmon populations
• 15 - 20% of all streams have disappeared
You are
here!
lost stream
endangered
stream
FRAP 1997
What is role of overfishing in stock endangerment?
• Has caused stock depletions (depressing stocks thus making them at
greater risk of extinction from other causes), and supplemental stocking
(previous lecture) has put some stocks into ‘special concern’ category.
• What about ‘big bad’ forestry?
• Upper Adams sockeye driven to extinction by a splash dam in the early 1900s
• Best evidence of a ‘forestry’ practice causing a stock extinction
• After the dam was removed there was some recolonization and transplants
• Enabled a ‘new’ population to establish
End on a zinger: The Oregon Chub
The First Fish Ever Taken Off The U.S. Endangered Species List!
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Involved working with landowners to restore key habitats, breeding
and transplanting fish and altering dam releases to more closely
resemble natural river flows
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“Twenty years might seem like a long time (to get it off the
endangered list). On the other hand, if you think of the 150 years of
habitat modification that went on before, it is pretty darn quick."
Huffington Post – Feb 2014