Salmon Aquaculture: Lessons from New Brunswick Inka Milewski, Science Advisor Conservation Council of New Brunswi Port Mouton, Nova Scotia November 15, 2006
Jan 31, 2016
Salmon Aquaculture: Lessons from New Brunswick
Inka Milewski, Science Advisor
Conservation Council of New Brunswick
Port Mouton, Nova Scotia
November 15, 2006
Salmon Aquaculture: Lessons from New Brunswick
• Economically sustainable?
• Ecologically sustainable?
• Well-regulated?
Economically Sustainable? “mom and pop” to Multinational
1986 1996 2006
Number of Farm Sites 28 74 98
Production 727 mt 16,300 mt 35,000 mt
Number of fish per farm 7,000 70,000 300,000 – 400,000
Price per pound (wholesale) $12.82 CND $7.55 CND $2.50 CND
Value of salmon sales $9.2 million $122.5 million $200 million
Number of Companies 28(1 corporations control 1
farm)
45(3 corporations control
53 farms)
12(1 corporation controls and/or
contracts from all farms)
2006 Salmon Farm Sites
Economically Sustainable?: Government Driven and subsidized
• From 1985 to 1996, ACOA pumped over $34 million into NB’s salmon aquaculture; 60% was direct contributions and grants
• In 1987, NB Salmon Grower’s Association formed; the Association received $4.3 million from government for their work between 87’-96’
• Beginning in 1996, outbreaks of ISA resulted in the slaughter of millions of fish; in 1997- 98 federal government paid out $32.5 million and the province $8 million in compensation
• In 2000 DFO launched Program for Sustainable Aquaculture and dedicated $75-million over five years with $15-million per year thereafter
• In 2004, DFO Minister, Gerald Regan, creates Aquaculture Management Directorate within DFO “to ensure aquaculture is more of a priority”
Ecologically Sustainable? Impacts of Salmon Farms
• Environmental impacts are associated with net pens, fish feed and use of chemicals and drugs
• Many effects still not studied– impacts of net pens structures
on the behaviour of migratory species
– loss of foraging, spawning and/or nursery habitat for wild species as a result of waste accumulation
– sub-lethal effects of pesticides on non-target species
Ecologically Sustainable? Waste Impacts of Farms
• By volume, largest component of waste discharges from finfish aquaculture operations are fecal wastes
• 95-98% of wastes deposited on the bottom are re-suspended in days and transported elsewhere
How much Fecal waste is released from salmon farms?
1 salmon farm1 200,000 fish1000 mt
182 mt of fecal waste/year1
Equivalent to fecal wastes from 2667 people1
93 salmon farms in S.W.N.B.33,600 mt in 20012
6115 mt of fecal waste/year
Equivalent to fecal wastes from 89,611 people
1Source: Hardy 2001 2NB. Department of Agriculture, Fisheries and Aquaculture
Changes in Benthic Diversity with Increased Organic Loading
Animals and bacteria in sediments produce H2O and C02
More nitrogen compounds like ammonia (NH4 ) are produced
More sulphur compounds like H2S are produced
More methane compounds (CH4 ) are produced
Organic loading
O2 levels drop, C02 levels increase, Redox values drop
Ammonia and sulphide levels increase
Animals diversity decreases, pollution tolerant species increase
Microbial community changes to bacteria tolerant of low 02
220 m
1 salmon farm (200,000 fish) 2 X 10 net pens Each net pen is 22 m in diameter
9680 m2
~ 2.5 acres
44 m
29,120 m2
~ 7.5 acres + 30 m Mixing Zone
104 m
280 m
Area of seafloor potentially impacted by wastes
Control or Reference Site
Former Fish Farm
N
Crow Harbour Samples Control Site Samples
Mean Redox -154.38 mVNHE Mean Redox 34.92 mVNHE
Mean Sulphides 1308 µM Mean Sulphides 29.73 µM
Mean no. of species 14 Mean no. of species 31
Species diversity 2.58 Species diversity 3.85
Control site sediment core (2003) Farm site sediment core (2003)
-400
-300
-200
-100
0
100
200
300
Redox - mV
NHE
Crow
Harbour
(pre farm)
Crow
Harbour
2002
Crow
Harbour
2003
Crow
Harbour
2004
Reference
Site 2002
Reference
Site 2003
Reference
Site 2004
0 cm
4 cm
8 cm
Mean sediment Eh at a former fish farm in Crow Harbour and a Reference Site (2002-2004)
Sediment Depth
Mean Surface Sediment Sulphides at a former fish farm in Crow Harbour and a reference site (2002-2004)
0
200
400
600
800
1000
1200
1400
Crow Harbour 2000 (pre farm)
Crow Harbour 2002Crow Harbour 2003Crow Harbour 2004 Reference Site 2002Reference Site 2003Reference Site 2004
Sulphides (uM)
0
5
10
15
20
25
30
35
40
2002 2003 2004
Total Taxa
RS
CH
0
0.5
1
1.5
2
2.5
3
3.5
2002 2003 2004
Diversity (H')
RS
CH
Crow Harbour (CH)farm vs reference site (RS):Species Numbers and Diversity 2002-2004
Well-Regulated? • the first 10 years (1979-1989) salmon aquaculture was
virtually unregulated• Province signed an MOU with DFO in 1989 which gave
province development and licensing responsibility• DFO and EC still retained responsibility for enforcing section
35 (prohibits a HADD - harmful alteration, degradation or destruction of fish habitat) and section 36(3) (prohibits release of deleterious substances) of Fisheries Act
• Monitoring of farms sites by province began in 1989 as a pilot project
• First monitoring report in 1992 found 37 or 48 farms had moderate to high environmental impact ratings
Well-Regulated?• In 1991 New Brunswick gets an Aquaculture Act that sets
site allocation rules (by then there are already 57 farms); confidentially provisions of the Act prevent public release of monitoring data
• By 1997, disease and sea lice outbreaks, conflicts with local fishermen over allocations of farm sites prompt a review of the Site Allocation Policy – “moratorium” on new sites imposed
• In 2002 environmental monitoring transferred to provincial Environment Department and environmental performance guidelines are finally established; annual monitoring results are finally made public
• In 2003 Provincial Department of Fisheries and Aquaculture finally establishes a Compliance and Enforcement section
Well-Regulated?
• In 2005, DFO Regional Director General (Atlantic Region) finally requests DFO Science Branch prepare an expert opinion on the effect of sulfides on diversity of benthic community
• According to expert opinion:– 60-70% of biodiversity is lost when sulfides are 1500 – 3000 µM, – 70-90% of biodiversity is lost when sulfides are greater than 3000
µM,
• 2006,province changes environmental rating system for sulfide levels that constitute a HADD under the Fisheries Act (from 6000 µM to 4500 µM) – the level is set higher than the expert advice provided by a DFO scientist in 2005
Well-Regulated?
Annually, 25-30% of farms are allowed to operate even though sulfide levels in sediments are in the high impact category and would likely be in violation of section 35 of federal Fisheries Act.
New Brunswick’s Salmon Aquaculture Industry
• Economically sustainable? – not without government subsidies
• Ecologically sustainable? – not without environmental subsidies
• Well-regulated? – not for ecological impacts
2005 Nova Scotia Industry Consultation
• Complaints by industry that application and approval process was too burdensome and too long
• Federal EA process was viewed as a problem• Scarcity of suitable inshore sites, federal
restrictions on movement of eggs and fish, public opposition on sites, lack of government support to reduce financial risk of disease other “catastrophic” problems and lack of direction from government seen as problems by industry
2005
- 48 salmon sites
- 16 in Gulf of Maine Region
- Rest along the South Shore and Bras d’Or Lakes
Measurement Maine11
(salmon aquaculture )New Brunswick22
(Finfish aquaculture)Nova Scotia33 (“Generic”Aquaculture)
Monitoring Requirements
Remediation Triggers Monitoring Requirements
RemediationTriggers
Monitoringrequirements
RemediationTriggers
Redox Potential(Eh, mV)
U -100 to 0 U < 0 U
Sulfides (µm) U 1300 -6000 U > 1300 U > 3000
Microbial(Beggiatoa sp.Coverage)
U > 25% photo coverage U U
Anoxic Sediment(Sedimentcolour)
U U U
Pollution-TolerantTaxa
U number of individuals in asingle taxa > 70%
Pollution-Sensitive Taxa
U > 50% reduction in meanabundance not identified aspollution-tolerant
Taxa Richness U > 25% reduction in totalnumber of all taxacompared to mean baselineor reference site
Azoic Conditions U > 50% reduction in totalabundance compared tomean baseline or referencesite
U U
SedimentDescription and/or % OrganicContent
U U U
Video Transect U U U
Copper U
Zinc U
Medications U
Monitoring Requirements
Remediation Triggers Monitoring Requirements
RemediationTriggers
Monitoringrequirements
RemediationTriggers
U -100 to 0 U < 0 U