Aquatic Ecology final Flashcards
Aquaculture impacts
escapement waste discharge fish health water quality coastal activities global feedfish populations marine foodwebs
Captured/farmed fishery products flow chart
aquatic production (PP)– capture fisheries (discarded bycatch, human consumption)- fish meal - aquaculture (livestock) -human consumption (terrestrial agriculture)
Captured/farmed fishery products flow chart, negative feedbacks
- feedbacks on PP
capture fisheries, fish meal, aquaculture
Captured/farmed fishery products flow chart, aquaculture negative feedback
waste, habitat modification, pollution, impacts on population/food web dynamics, escaping feral species
PP proportion division from capture fisheries
approximately:
1/4 bycatch (waste)
1/4 fish meal
1/2 human consumption (straight)
PP proportion division from fish meal
1/6 Aquaculture
2/6 (1/3) livestock
3/6 (1/2) human consumption
changes in total capture
increased substantially
human consumption from aquaculture & capture fisheries, 1997
~95 million metric tonnes (worldwide)
environment issues from aquaculture
discharge degrades water quality
alter/degrade natural habitat
pressure from multi-uses on water system
Biological issues with aquaculture
over-exploitation of organisms - food web consequences
chemical use (health concern)
introduction/transmission diseases, parasites, aliens
contamination
production quantity and value vs. year
exponential increase
huge increase since 1980’s
2004 quantity: ~60million tonnes
2004 value: $70 billion US
aquaculture production, china/asia/rest of world
China by far the hugest proportion and largest increase (50million tonne increase in 30yr), Asia ~20million tonne increase in 30 yrs, rest of world increased less than 10million tonne (an IS less than 10)
world population 1950-2002
2.56billion –6.23billion
now ~7billion
consumption per capita, 1950-2002
~doubled since 1950 (10-22kg per person/per year)
changes in marine fish catch, 1950-2002
~20million tonnes – 80/90million tonnes
Utilization of fish, 2000’s
40% fresh 30% non-food (feed) 18% frozen 7% cured 8% canned
Changes in utilization of fish since 1960’s
increase in fresh fish- better transportation, maintenance
increase in frozen fish
Canada’s Atlantic cod
1980-1990 catch was ~500,000 tonnes, 1995 drops off to nothing, overexploited to population collapse, still can not recover b/c niche space taken over
human fish consumption as a percent of total animal protein
worldwide 16%
N America 6.6%
Africa 21%
Far East 28% (Asia, healthier, cheaper, less fresh water needed)
World farm salmon production, 1980-2003
BC, Norway, Chile, UK all increase in production
Norway MAJOR increase
Changes in world farm salmon production, 1996-2002
Chile +235%
Norway +71% (but highest total value)
Scotland +89%
BC +96% (but lowest total value)
Changes in wild salmon, US + Canada, 1988-2002
chinook, chum, coho, sockeye- all decrease in production roughly 30%, decrease in at-vessel price/lb ~70%
pink production +11%
Changes in farmed Atlantic Salmon, US + Canada, 1988-2002
production: +895,000%
price: -61%
mariculture
cultivation of marine organisms for food and other products in the open ocean
aquaculture by environment (2004)
Brackish 6%
Freshwater 43%
mariculture 51%
what is grown in aquaculture
very diverse: crustaceans (shrimp, crab), finishes (carps, tilapia), filter feeders (mussels, oysters, scallops..), aquatic plants, carnivorous fish (salmon, bass, bream)
World aquaculture production by volume, by country/continent, 2004 (the main players)
China 70%
Rest of Asia 22%
Other 9%
w/i Other: W Europe 3.5%, Latin America 2%, NA 1.27%
World aquaculture production by value, by country/continent, 2004 (the main players)
China 51%
Rest of Asia 29%
Other 20%
w/i other: WE 8%, LA 7.5%, NA 1.86%
fastest growing food producing industry
aquaculture
problem of rapidly increasing aquaculture
demand for feed ingredients increasing rapidly, supply limited
feed used in BC, 2000
65 million kg
to produce 49million kg farmed fish
what happens to feed
20% deposited as feces
unused feed deposited as solid
excretory release of dissolved material
chemical components of aquaculture feed
45-65% is Carbon
6-10% is N, 1-2% is P
total system loading unknown
whats so important about increased N, P
two most important nutrients responsible fro eutrophication
Estimated loading to BCs coastal water from aquaculture
7.1 million kg of C
1.3 million kg of N
236,000kg P
all per year
may not be significant for entire system, but definitely important in enclosed bays
how salmon are unlike other ‘farm’ animals
carnivorous, feed is 45% fishmeal, 25% fish oil
cost of producing farm fish
2.8kg wild fish = 1kg farm fish
area required to produce the feed = 40-50,000X production area
Amount of PP being used for aquaculture
European industry - ~90% of North Seas’s PP
BC - 7.8million ha of ocean (278X area of all terrestrial BC horticulture)
what’s underneath a fish farm???
black sediment - highly organic material, reductive, lacking oxygen
taxa richness vs [sulfide] (µM)
negative linear
appears well correlated, but also a pretty wide spread in the data
whats happening with the sulfide
increased Cord – increased sulfide accumulation– kill benthic inverts.
rockfish near farms
found to have higher Hg content closer to fish farms
why rockfish?
not very migratory, good proxy for local condition
why higher Hg near fish farms?
oxygen reduction due to C loading = anoxic sediment– Hg methylated and converted to usable form (methyl mercury)– accumulates in tissues– produces neurological effects
levels of contaminants in farm produced, store bought, wild salmon
farmed & most of store bought ~ equal in all of the contaminants/carcinogens tested (PCB, dioxin, toxaphene, dieldrin), wild lower
some store bought appears to be wild but more is farmed
fish utilization and supply (excluding China), trend
1950-2002
population linear increasing
food supply non changing
changes in fishmeal use, 1988-2002
1988: Poultry 59%, aquaculture 10%, pigs 20%
2002: poultry 22%, aquaculture 46%, pigs 25%
what are poultry being fed now
bluegreen algae (more deeply coloured yolk, carotenoids)
fish oil use
1990: edible 76%, aquaculture 16%, industrial 8%
2002: edible 14%, aquaculture 81%, industrial 5%
Other sources of fish feed
by-catch
fish processing by-products
plant products
livestock by-products
Canada salmon feed
lowest fishmeal and oil inclusion rate
SA fish feed
41% of all fish used in feed, including: Anchoret, Chilean jack mackerel, South American pilchard
very important low trophic level fishes!!
top marine capture, 2002
anchoveta (9.7mt) pollock (2.7mt) tuna (2.0mt) capelin (2.0mt) herring (1.9mt)
changes in salmon fishmeal/fish oil use
fishmeal +185%
fish oil +577%
changes in carp fishmeal/fish oil use
fishmeal 750%
oil 70%
changes in crustacean fishmeal/oil use
fishmeal 1363% increase
fish oil 2660% increase!
overexploited species for fish feed
Peruvian anchovy- 6.2mt harvested 2003, recovering, overfished
Chilean jack mackerel- 1.7mt harvest 2003, fully fished, overfished
up to 11 species in this list are fully fished, unsustainable!
SA harvest of feed fish
1960-70’s exploit anchoveta– collapse– SA pilchard takes over niche– exploit them– collapse– chilean jack mackerel moves in..
natural cause of population decline in fish species
El Niño- huge decrease 1998
capture-reduction
how much is caught relative to time vessel spends out (? maybe) .. lowest in El Niño yrs
larger scale effects of harvesting fish feed
taking ~85% of sea predators food; seabirds, marine mammals
Effects of farming on wild salmon health
smolts travelling to ocean pass by fish farms, pick up significant infections rates; many farm fish have sea lice (infestation from low diversity, close quarters)
forage fish
prey fish/bait fish, small pelagic fish preyed on by larger predators for food
areas of application for stable isotopes
paleoclimate reconstruction (O2) paleolimnology terrestrial aquatic linkages food web ecology migratory studies individual feeding behaviour
paleolimnology, stable isotopes
historic patterns of productivity, mostly C, N
terrestrial aquatic linkages, stable isotopes
terrestrial–> aquatic (lake management)
marine derived nutrients (salmon)–> terrestrial
food web ecology, stable isotopes
contaminant transfer, ecology
migratory studies, stable isotopes
birds, fish, zooplankton, mammals, C
how much time in open/coastal ocean
algae isotope ratio highly variable in open/coastal
individual feeding behaviour, stable isotope
niche shift, omnivore, trophic position
within single population
ex. stickleback - some neutral all the time, some pelagic all the time, all related to evolution, studiable by isotopes
∂13C ratios
C fractionates during photosynthesis, little-no fractionation up food chain
determine what food sources are based on ∂13C ratio
∂13C determination of food source possible with following conditions
large isotopic separation (btw food sources)
over time food signatures are stable
two/few food sources
examples of ∂13C determination of food source
middle of lake - very highly negative
close to littoral zone (terrestrial C) - less negative
∂15N in food web ecology
tells trophic level, fractionated throughout trophic levels
trophic enrichment of ∂15N
2.92+/- 0.8 ‰
typical ∂15N signatures
algae 4-8‰
invertebrates 8-16‰
forage fish 10-14‰
predatory fish 10-18‰
typical ∂13C signatures
off-shore -28‰ (depleted)
near-shore -14‰
why is ∂15N fractionated up trophic level
preferential excretion of 14N
high ∂15N
heavy
more positive
atmospheric N2 ∂15N
0‰
hasn’t been fractionated by organisms
enriched in ∂13C
heavy
less negative
∂13C never positive
depleted in ∂13C
light
more negative
∂13C never positive
inorganic fertilizer ∂15N
0‰
made from captured atmospheric N
fractionation
in a chemical reaction one isotope proceeds at a quicker rate than the other due to a slight difference in mass (lighter synthesized faster/easier, more efficient)
two types of fractionation
animals- body tissue
algae
animal tissue fractionation
14N is preferentially released so 15N increases relative to its food source
algae fractionation
photosynthetic enzyme can process 12C molecules quicker than 13C, utilize it preferentially
based on size
algae photosynthetic enzyme that processes carbon molecule
RUBISCO
isotopic composition in foodweb
sediment: ~-30, towards terrestrial
inverts: ~-33, ~50/50 terrestrial/planktonic
piscivorous fish: ~-28/-30 pretty close to terrestrial
littoral zone
near shore area where sunlight penetrates all the way to the sediment and allows aquatic plants (macrophytes) to grow
Loch Ness Zooplankton, temporal shift in C signature reflecting food source
winter- low PP, most C is detrital, POM (less - ∂13C), zoop signature matches POM
summer- higher PP, signature drops to mirror to algae ∂13C (more - )
reconstruct historic salmon runs with ∂15N
sedimentary ∂15N correlated to number of spawners
250,000spawners ~ 6‰
1mill spawners ~ 8.5‰
∂15N sediment signature change in 1900
dramatically drops off, commercial fishing
significantly different ∂15N signatures along the river
higher ∂15N signature in root feeders, omnivores, detritivores, predators.. BELOW falls (input of high ∂15N source, salmon)
Class 1 lake
lack preferred lake trout prey, pelagic forage fish, causing lake trout to feed on zooplankton and zoobenthos
class 2 lake
contain at least one species of pelagic forage fish, resulting in piscivory
class 3 lake
pelagic forage fish and glacis-marine relict invertebrate predator Myis relicta - elevates lake trout to fifth trophic level
measuring trophic level by ∂15N ratio
gut contents
digestibility highly variable
assumptions made
pelagic
Any water in a sea or lake that is neither close to the bottom nor near the shore
pelagic zooplankton signatures
variable! needs to be established as a baseline
study found differences in calanoid copepods, Daphnia, Holopedium
lake to lake isotope signatures
highly variable depending on inputs (human, animal, fertilizer, salmon)
PCB (ng/g wet mass) vs trophic position
liner increasing
class 1 at low end
class 2 in middle
class 3 at top end (most trophic positions)
appears to be due to increased % lipid with increased trophic level
PCBs and lipids
lipophilic contaminants, accumulate in fat (lipophilicity)
unnatural, remain in bodies
∂15N trophic position vs. dietary trophic position
highly correlated = N good measure of trophic position
Hg (µg/g) vs. Lake class
higher in higher class higher if smelt present in each individual class
∂15N vs ∂13C, Arctic Lake System, Lake Trout
LT top predator - highest ∂15N, ~middle of ∂13C spread- consumes pelagic and littoral fish
Log Hg (µg/g wet weight) vs. ∂13C
decreasing
terrestrial source has lower level of Hg
if LT feed more on nearshore/benthic than offshore/pelagic they will have lower Hg
Hg consumption guideline
0.5µg/g
one meal per week (non pregnant adults)
[Hg] (µg/g) vs. ∂15N (‰) in Ontario, Quebec lakes
all Class 2 and 3 fish are above consumption guideline level of Hg
sport fishing species, widely consumed
US Hg blood levels
300,000-600,000 children/yr cord blood Hg level > 5.8µg/L, a level associated with loss of IQ
cost of methyl mercury toxicity
lost productivity (lower IQ) $8.7bill/yr
Daphnia spp. ∂15N (‰) vs levels of land-use (low, high)
low land use (Sooke lake) - 0-5‰
high land use (Shawnigan lake) - 6-13‰
Sooke lake
our drinking water
fully protected
Shawnigan lake
developed
lots of septic
highly enriched in ∂15N
Caffeine (ng/L) vs. ∂15N in Mussel Tissue
linear positive
caffeine from septic contamination
robust indicator of fecal contamination
Caffeine (ng/L) vs. Shoreline Development (lots/km^2), Shawnigan lake
linear positive
denser housing = more septic = fecal input = more caffeine
∂15N (‰) vs. year, Sooke Lake and Shawnigan lake sediment cores
Shawn. has increased from ~1-3 as a result of human development
Sooke- has some spikes from building new dams/raising the dam- inundating land
EBS
Eastern Bering Sea
EBS 2002-2005
large-scale warming event
followed by 2yrs cooling event (2006-07)
EBS sampling
zooplankton from 186 stations each year
13,000 fish
600 zooplankton
change in abundance of juvenile salmon and forage fish
increase in warm years
decrease in cold years
in salmon, juveniles, forage fish
EBS zooplankton ∂15N
must be determined for baseline
higher in N EBS- upwelling? predatory?
Juvenile Sockeye Salmon ∂15N, EBS
warm years- up to 2 levels above zoop. = piscivory
cool years- remain small, stay near shore, can’t grow enough to move up food chain
Juvenile Pink Salmon Trophic position above zooplankton, EBS
pink salmon normally zooplanktivorous..
in wam years- up to 2 levels above zoop., piscivorous
Juvenile Chum Salmon trophic position above zooplankton, EBS
chum usually feed on jellies
warm event- up to 2levels above zoop., piscivorous
Signatures in northern Bering Sea
warm year- less negative ∂13C, near terrestrial loading (from Yukon river)
cool year- more negative ∂13C, pelagic source
not really a pattern in ∂15N
Signatures in Southern Bering sea
Warm- higher ∂15N, higher trophic position, trophic enrichment
Cool- lower ∂15N, lower trophic position
sediment ∂15N profiles from NH lakes
26 profiles, almost all show drop in ∂15N since 1900 = depleted N signature from fertilizer use! recall (fertilizer is from atmospheric N2)
global fresh water
3%
99.7% of that 3% is unavailable (glaciers, deep aquifers)
Where is our available water
80% is in 20 large lakes
95% is in 145 lakes
water demand per person
1400-1800m^3/person/year
1.4-1.8million L
unequal distribution of water
little water in some parts of China, France, unglaciated US
abundant in Canada, Scandinavia, NZ, Russia
Water required for some crops
70L for 1 apple 50L for 1 orange 140L for 1 cup coffee 2300L per kg rice 15,500L per kg beef
water exchange times, lakes basin
days - centuries
balance of inflow, precipitation, evaporation
water balance affected by
dams, diversions
Aral Sea
1.3million km^2 watershed
before 1960, 4th largest lake in world 67,000km^2
Kazakhstan and Uzbekistan
Aral Sea, 1920s
water diversion for agriculture (especially cotton), storage for hydroelectric power
Aral Sea ppt
historically- 10ppt
Now- 34ppt (Ocean salinity!)
Aral Sea, since 1960s
85% volume lost (42,000km^2 lost)
65% SA lost
lakeside towns now 100-150km away
former lake area dry, saline
Affects of Aral Sea changes
all fish species gone
60,000 fishing jobs lost
massive ecological change- species extinctions
local climate substantially changed
Aral sea historic harvest
48,000T/yr
largest fish processing plant in USSR
Aral Sea 2000’s
area 24,000 volume 175 salinity 65-70 separated in to two lakes in 1993 2010, only 1 lake left
Economic Consequences of Aral Sea loss
fishing, agriculture, cost of water rights
Health Consequences of Aral sea loss
highest child mortality in former USSR life expectancy decrease 64-51yrs (in ~60yrs) highest world rate of esophageal cancer widespread DNA damage birth abnormalities 5X EU, infertility
What’s causing the health consequences, Aral Sea
large volume of agricultural chemicals, waste
carcinogenic salt/chemicals transported by wind
Pesticide use in Aral sea area
72kg/ha
compared with US- 1.6kg/ha
Valiant Dam Italy
265m concrete arch dam, steep walled mountain valley
built in 1960
limestone/clay layers = slides as reservoir filled
Vainont Dam, 1963
debris slide
displaced 30x10^6 m^3 water over dam (1/4 of contents)
2500 deaths downstream
China, S–>N water diversion
un-uniform water distribution
divert water from major S rivers to industrial in low water N
3X cost of Three Gorges
3 separate routes
Three Gorges Dam, China
once largest in world
flood control, diversion of water to N, hydro power, transportation
Three Gorges Dam problems
loss of agriculture, historical sites
changes to climate, public health, soil stability
Dam changes to soil
when water bodies are made, soils release heavy metals they have been holding into water
Colorado River, 1928
water treaty
7 states get 19km^3
Mexico 1.8km^3
Colorado River, 1930’s
major water diversion to LA
Colorado River, 1935
Hoover Dam
Colorado River, 1960’s
Glen Canyon Dam
[salt] exceeds 1.5g/L
ruins Mexico agriculture (collapse)
Response to Glen Canyon Dam - Mexican agriculture collapse
Yuma (Arizona) desalination plant
$1B/yr
Ground Water
give stability to ground over draining creates space in ground sinkage drawdown water table subsidence
Mexico City
built on a lakebed, elevation 2240m
Initially water flowed in and had to be diverted out
Changes in Mexico City
rapid growth (more than 20million)
Had to pump in water but had very poor infrastructure (holes in pipes)
subsidence 1m/yr
buildings tilting, roads, pipes moving
Canadian water
Great lakes: 240,000km^2
20+% of world FW
85% of NA water
45mill people in watershed (15mill Canada)
Canadian water export
policy unclear (provincial vs. federal)
NAFTA may require selling water to US
potential profit, damage degradation loss
Unclear water policy
freshwater is provincial jurisdiction
who can use water is federal - dept transportation, dept fisheries, dept fish&oceans
NAWAPA
North America Water and Power Alliance potential water diversion: Rocky Mt trench -- Texas from Mackenzie river valley 240 dams nuclear power to pump it
GRAND Canal dam
Great Recycling and Northern Development channel
potentially divert from James Bay – Great lakes
Dam/Diversion problems and education
political economical public education important International co-operation conservation water re-use
Dam impacts, land inundation
mobilizes DOC & Hg to food web
Hg accumulation in fish
neuro-degenerative symptoms
loading to ocean (of water) is decreasing, may increase ocean salinity
MPA, IUCN definition
Any area of intertidal or subtotal domain, together with it’s overlying water and associated flora, fauna, historical and cultural features, which has been reserved by law or other effective means to protect part or all of the enclose environment.
MPAs attempt to
protect sensitive habitat
conserve biodiv.
shelter vulnerable/endangered species
boost fisheries catch
IUCN
international union for conservation of nature
MPA coverage, now
less than 1% of worlds oceans
Newfoundland Cod, historically
fished from small dories, land lines
spawning ground far offshore (unreachable)- natural protection, refuge
dories
small, shallow-draft boat, 5 -7m, usually lightweight with high sides, flat bottom and sharp bows
Fishing technology
no natural fish refuges
very long range & time
targeting capability
Traditional fishery protection laws
species specific
i.e. Atlantic Cod
MPA, allowable
no ocean dumping or dredging
no exploration for or development of non-renewables
fishing/extraction permitted
fully protected MPA
“No-take zones”
“Areas of the ocean completely protected from all extractive and destructive activities”
no fishing, removal, dumping, dredging
Coverage of ‘no-take’ zones
less than 0.1% of the worlds ocean
Accidental MPA
Cape Canaveral
US gov’t creates security zone around Cape C. satellite launch zone
MPA benefits
Increase/Enhance: fish abundance fish size/age reproductive output species diversity habitat complexity fishery yields in adjacent grounds overall biomass increase
“Fishing the Edge”
fishing boats sitting right on edge of MPA
Importance of letting fish grow big
reproductive output
large fish = higher reproductive output
23”in vermilion can produce 17X more young than 14”
Sustaining Sea Otter, kelp forest
protects fish abundance, mussel growth, other inverts and crustaceans, changes to predatory sea bird resources
Fish Abundance, sea otter presence
~5X higher w/ S.O. present
Mussel Growth, sea otter
~2X w/ s.o. present
Gull diet, sea otter
Diet is 90% fish w/ s.o. present
90% macro inverts. without sea otter
Bald Eagle diet, sea otter
s. o. present: diet is fish, mammals, birds ~ equal
s. o. absent: ~70% of diet is seabirds
control sea urchin populations
sea otter
predatory fish species
spiny lobsters
urchin/kelp feedback
lack of predation– urchin population boom– urchins feed on kelp holdfast– kelp wash away in tide– habitat is lost
Anacapa Island MPA
California - predatory fish, lobsters regaining populations- increased urchin predation- sustainable kelp forest
Idealized MPA
Equilibrium state: maximized species diversity many linkages in food web redundancy stability
Ecological redundancy
organisms having several food sources
“Spillover effect”
= export of adult fish out of MPA
high fish density within MPA - leave protected area (no physical boundary)
MPA size determination
dependent on species to be protected
too large detracts from fishery
too small ineffective
Sizes of MPAs
not self-sustaining
moderately self-sustaining
completely self-sustaining
MPA not self-sustaining
most species lost
high periphery : area
unsustainable
small effect on recruitment and commercial fishing
too much loss out of reserve to be effective
MPA moderately self-sustaining
some species lost adequate periph:area some individuals retained significant source of recruits to fished area some reduction of fishing grounds good balance of benefits for all
MPA completely self-sustaining
all species retained low perish:area small spillover little recruitment outside reserve severe reduction to fishing ground little export
Where should MPAs be?
vulnerable habitats
important habitat
species rich habitat
spawning grounds
MPA and migratory species
doesn’t really protect migratory species, better for stationary species (ex. rock cod)
DOES increase salmon prey though
MPA vulnerability
currents flow through, pollutants can flow through
MPAs necessary but not adequate
Lake Victoria
SA 69500km^2 depth Zm = 39m several invasives: Nile Perch, water Hyacinth overfishing (gillnets) massive loss of endemics loss of Oreochromis fishery
Lake Victoria native population
300 Cichlid fish most diverse cichlid population 2/3 gone highest vertebrate extinction rate Oreochromis sp. (algal feeder) - major protein source
Management troubles of Lake Victoria
shared by 3 countries that don’t get along
Uganda, Kenya, Tanzania
Water hyacinth
mostly near shore environment- highly mixed/dynamic water bodies, sheltered small basins
clog up waterway
Major aquatic plants (invasive)
Hydrilla (US) Elodea (Europe) Eurasian milfoil (NA) Purple loosestrife (NA) Canary Reed Grass (NA) take over shallow transparent water bodies huge economic losses
Invasive plant management
Herbicides
Mechanical harvesting
biological control
Invasive plant management, biological control
introduce something else that will prey on it (kind of like how coopers hawk controls European starlings)
Invasive plant management, mechanical harvesting
bulldozers!
Nile Perch
large piscivorous fish
introduced in 1960 for British sport fishing
up to 300lbs
Lessons of Lake Victoria
introduction of one species changed entire trophic dynamics of one of the largest lakes in the world
% of total catch vs year (Lake Victoria)
haplochromines (cichlid) majority of prey catch until ~’74
1974-1980 majority is haplo. and omena
after 1980 majority is Nile perch and omena
Omena
anchovy-like minnow
Standing stock estimates, Lake Victoria
Kg/ha vs year
Native - ~60 in 1970’s down to ~0 in 80’s, 90’s
Introduced- ~30 in 80’s –> ~70 in 90’s
almost entirely introduced species
Oxygen in Lake victoria
O2 (mg/L) vs Month
surface ~10 all year
bottom: less than 5 all year, anoxic in winter, highest in summer
loss of haplochromines (algal readers) changed oxygen structure
bottom up control
Eastern Bullfrog
widely introduced for aquaculture (restaurants) Europe, Asia, Japan
replace/consume prey of/ infect native amphibians
spread of Eastern Bullfrog
California 1905
Burnaby 1940
Elk Lake 1960’s
Eastern Bullfrog diet
omnivores
insects, fish, ducklings, rodents
Invasive Zooplankton
Daphnia lumholtzii (Europe-NA)
Bythotrepes (NA)
Cercopagus (black sea-baltic)
Mysis relicta (Ghost shrimp, glacial relict)
Success of invasive species
distinct features that give them the advantage
ex. sharp spine, anti predator mechanisms, larger T/resource/habitat ranges
Mysis relicta foodweb changes
introduced to Flathead river-lake ecosystem to increase kokanee population. Only feed at night, competition for kokanee’s resources.. decreases kok. pop., lake trout, bears, eagles, copepods, cladocerans (water flea)
Invasive filter feeders
Zebra, Quagga mussels introduced from ship ballast from E Europe, 1988 few predators (dicks, 1 fish) widespread through Mississippi major financial impact larvae continue to spread with boats
Why are so many eggs released in St. Lawrence seaway
ships have to release ballast to rise in canal
Effects of increased mussles
clog water pipes, make great lakes more oligotrophic, affect fish productivity
Origin of foreign fish
mostly from:
South America, Asia, Africa, Central America
Laurentian Great Lakes
most important NA water source SA 244,000km^2 V 23,000km^3 21% worlds water 84% NA water 1/3 of Canadian Population
Great Lakes fish introductions
1600’s Carp
1930’s Lamprey, alewife
1960’s Pacific Salmon
Rainbow smelt, reffe, goby (ballast water), zebra mussels
Lamprey, alewife introduction great leaks
1930’s
upper lakes via Welland canal
loss of lake trout, whitefish
alewife - zooplanktiverous–> anoxia
Welland Canal
waterways connecting Atlantic ocean to great lakes
Pacific Salmon introduction to great lakes
1960’s
chinook, coho
introduced to deal with alewife (biological control)
salmon spawn upstream, don’t go to ocean, very contaminated
VI fish introductions
Sunfish
Rainbow Trout
Small Mouth Bass
Yellow Perch
Other introduced species
Asian carp/Grass carp Cormorants Bang Nutria Didymospenia
Asian Carp, Grass carp
introduced to control aquatic plants, took over
biological control
Cormorants
Lake Ontario
efficient gobies consumer (invasive fish)
fewer sport fish
Bangia
filamentous algae forming extensive growth
Nutria
‘river rat’ -kinda looks beaver/marmot like
very efficient foragers
cause enormous damage
from SA
Didymospenia
filamentous diatom
choking river beds
decrease use of rivers as spawning grounds
Caulerpa taxifolia
mediterranean
1984 first discovered
1990 1ha authorities informed (in writing)
1994 declared major threat 1500Ha
1998 UN law to battle invader 4600Ha
1999 covers 97% of suitable surfaces France, Monaco, Italy
Invasive cats
feral populations, one of worst invasive mammalian predators direct predation competition hybridization disease transmission ecologic process alteration behavioural change
Google Earth/GIS
can be used to study introduction/coverage of invasive w/ time
google earth found to be 84% accurate at detection
fate of invasives, possible outcomes
Transport– introduction – success (fail) –spread (fast/slow) – impact (nuisance/non-nuisance)
dysentry
infection of the intestines resulting in severe diarrhea with the presence of blood and mucus in the feces
Water contamination
millions die worldwide/yr
rural/slums- high dysentry
amount of people in rural communities without access to safe water
77%
safe is in don’t die from it
children under 5 that die from diarrhea in rural/slum communities, due to unsafe water
35/1000
Women and school, rural/slum communities
40% complete 3years
intense effort to collect water
Water contamination, Canada
many sick, 7 dead in Walkerton, Not
~1000 small communities on boil water advisories (all the time)
Water quality parameters of concern
pathogenic bacterie/protozoans (intestine disease)
excessive nutrients/algae (neuro/hepato toxins, carcinogenic byproducts)
harmful chemicals
anthropogenic harmful chemicals in drinking water
pesticides, herbicides, metals, antibiotics, pharma-care products
chemical/biological/microbial waste from agriculture, livestock, industry, households
why larger communities at lower risk of water contamination
adequate resources
expertise operator training and treatment
money
able to own and control entire watershed
example of dharma-care water contaminant, St. Lawrence Seaway
endocrine disrupters causing fish to not develop sex
Siem Reap River (cambodia), water contamination
throw waste into same small waterbody that is used for drinking
Bangladesh water crisis
well water becoming contaminated with arsenic from contaminated groundwater = ulcers, amputations, gangrene, carcinoma, pigmentation issues
Bangladesh water contamination, solution?
develop ponds to harvest rain water and use slow sand filters to clean water to entire village
BC water utilities
3500 registered systems
over 90% unfiltered, only chlorination
most small, rural systems
most have no control over environment/source quality
higher rate of enteric illness than rest of Canada
Canada boil water advisories
over 1000 communities
higher for aboriginal communities
enteric illness in BC, Ontario/Quesbec, Praries, Atlantic
rater per 100,000 vs time
All have decreased by ~50/100,000 from 1987-97
BC ~50/100,000 more than O/Q/P
BC ~100/100,000 more than Atlantic
distance from water treatment plant
the further away you are the more at risk you are, may need second treatment
economic returns from the biosphere
protecting/sustaining the environment lowers health costs
Land-use activities
agriculture farming waste disposal pesticides/herbicides harvesting residential/industrial activities
Land-use activities cause loading of
pathogens nutrients metals/organics humic compounds pharmaceuticals
Surface/ground water protection and management must
Develop strategies to reduce loading
understand transport and fat of microbes and chemicals
Enhance community knowledge and understanding
Effects on/of water for public health
land-use activities
loading
quality of source
quality of output (tap)
Affect quality of source water
pathogens algae toxins TOC/DOC taste/odour chemicals (drugs)
Natural process affecting water quality
small vs larger grazer system
recall: large fish = large grazers = smaller microorganisms (bacteria/algae/pathogens) which also = better water quality! (another problem of fishing down the food web?)
processes that affect surface water quality
wildlife recreation forestry livestock drylands farming mining industrial urbanization climate
Wildlife and surface water quality
beaver, otter, rabbit, ungulates, waterfowl
Protistan parasites
Recreation and water quality
boating, ATVs, hiking, camping, pets, cottages, skiing
sediments, pathogens, hydrocarbons, herbicides
Forestry and surface water quality
roads, clear cutting, camps, storage areas, stream crossings, slash burning
microbes, turbidity, organic loading
livestock operations and surface water quality
clearing, manure, feedlot, recreation, soil erosion
microbes, nutrients, turbidity
drylands farming and surface water quality
clearing, pest/weed management, soil erosion
pesticide, herbicide, turbidity, salt
mining and surface water quality
clearing, roads, waste rock, tailings, dust, living/operations
turbidity, metals, acid mine drainage
Industrial practices on surface water quality
wastewater effluent, contaminated sites, roads
turbidity, chemicals
Urbanization and surface water quality
sewage, water extraction, roads, pets, clearing
nutrients, chemicals, turbidity, pathogens
surface water quality is a measure of
parasites, bacteria, viruses, turbidity, nutrients, algal toxins, pH, hardness, alkalinity, natural organics, metals, hydrocarbons, chemicals
water treatments
no treatment filtration sedimentation flocculation chlorination chloramination ozonation UV irrdiation
contamination in water distribution system (after treatment)
intrusion
regrowth
permeation
leaching
Intrusion, contamination in water distribution system
Pressure drop faulty pipes/gaskets cross-connections unprotected tanks contaminated soil/groundwater
regrowth, contamination in distribution system
distance from treatment plant
nutrient availability
regrowth conditions (biofilm)
regrowth in tanks/pipes
Permeation, contamination in distribution system
organic compounds
plastic pipes
elastomers
leaching, contamination in distribution system
piping material corrosion
pipe lines
tank lines/seals
flocculation
rocess wherein colloids come out of suspension in the form of floc or flake; either spontaneously or due to the addition of a clarifying agent
airborne ammonia
72% of the variability in airborne ammonia explained by expansion of swine population
1988-1998: 0.1 - 0.4ppm
N:P ratios based on source
highest: runoff of unfertilized field forest runoff rainfall manure seepage sewage
controls on algal biomass and blooms
nutrients
seasonality of nutrient input
physical properties of receiving system
structure of the foodweb
% Total phytoplankton biomass vs. Lot TP (µg/L)
with an increase in TP shift to dominance of cyanobacteria (blue/green algae blooms)
Mycrostin concentration (µg/L)
linearly increasing with TP, Toxigenic biomass, and TN
-increase # of algae = increase # of toxin producing algae
major sources of P
septic, sewage, storm water, fertilizers
biomagnification of BMAA example
cyanobacteria– cycad– flying foxes – Chamorro people
neuro-degenerative & hepato-degenerative disease
concentrations of BMAA biomagnified
cyano. 0.3µg/g
cycad 37µg/g
flying fox 3556µg/g
x10^2 per “trophic level”
Coagulation/flocculation
removes colloidal particles by adding coagulants
sedimentation
Floc settles down to the bottom
disinfection
kill bacteria and other organisms
filtration
remove particles through filters
disinfection byproducts
formed during treatment and disinfection
water treatment steps
source water–coagulation/flocculation– sedimentation–filtration– disinfection– storage
Victoria water treatment
only disinfection (UV)
Increasing disinfection
increases disinfection byproducts, carcinogenic
Risk vs. Disinfection Level
Microbial curve is decreasing
DBPs curve is increasing
trade-off.. ideally in lower level of both risks
some DBPs
disinfection by-products Chloroform Chloroacetic acid Chloro... Formaldehyde Acetone Acetic acid Benzoic acid
DBPs produced by
- Chlorine (produces almost all, strongest disinfectant)
Ozone, ClO2, Chloramines
Disinfection by-products and birth weight
∆Birth weight (g) vs Concentration (µg/L)
THM, chloroform - decrease function
THM
trihalomethane (chloroform)
∂13C as a tracer for water condition
less negative ∂13C (lighter?) – disturbed watershed
more negative – pristine water source
Caffeine
fecal bacteria enriched with caffeine, linear increasing (ng/L)
Mussel Tissue- high caffeine rates for high ∂15N
Ibuprofen (ng/L) vs. Caffeine (ng/L)
lakes all in the low left corner, ocean outfall very high in both
molecular fingerprinting
take DNA profile of E. coli and compare to animals- tell which animal produced the e.coli
gut bacteria specific to animal
can tell where specific contaminant came from
Shawnigan Lake facts
extensive development since 1900, more since 1970
forest harvesting
septic inputs
changes in fisheries from alien species
Sooke Lake facts
protected since 1900
raised three time (1910, 1970, 2002)
Introduction of Leech river water through Deception in 1988
chloramination
treatment of drinking water with a chloramine disinfectant. Both chlorine and small amounts of ammonia are added to the water one at a time which react together to form chloramine
main nutrient linked to algal blooms and toxins
phosphorous
Lake sediments
preserve past records
- can be used to see watershed changes and water quality
- sinking of plankton biomass
molecular fingerprinting
take DNA profile of E. coli and compare to animals- tell which animal produced the e.coli
gut bacteria specific to animal
can tell where specific contaminant came from
Shawnigan Lake facts
extensive development since 1900, more since 1970
forest harvesting
septic inputs
changes in fisheries from alien species
HPLC
High Performance Liquid Chromatography
chloramination
treatment of drinking water with a chloramine disinfectant. Both chlorine and small amounts of ammonia are added to the water one at a time which react together to form chloramine
main nutrient linked to algal blooms and toxins
phosphorous
Lake sediments
preserve past records
- can be used to see watershed changes and water quality
- sinking of plankton biomass
sediment core procedure
select study area and sampling site– take sediment cores– section sediment core– data analysis– analyze data
sediment core data analysis
Pigment detection and quantification using HPLC
HPLC
High Performance Liquid Chromatography
Total algal biomass (mg/g organic matter) vs. year, Sooke and Shawnigan lake sediment cores
Sooke lake relatively straight
Shawnigan 3-10X higher biomass than Sooke, large spikes
carotenoid pigment vs. year, Sooke and Shawnigan lake sediment cores
Shawnigan higher than sooke
Sooke watershed protection sustained excellent water quality over 100yrs
Zeaxanthin pigment (bluegreen algae mg/g) vs. year, Sooke and Shawnigan lake sediment cores
Sooke pretty close to 0 over most of range, almost entirely less than 0.01
Shawn.- all over 0.01, up to 0.04
∂15N vs. year, Sooke and Shawnigan lake sediment cores
~equal until 1920’s
both have increased
Shawnigan higher from human/animal loading
