Impact of fin-fish aquaculture on waterway health
Fin-fish farming has the potential to effect waterway health through the
deterioration of water quality and benthic habitats, introduction of pest
species and damage to threatened species. Impacts can occur in the near field
Water quality may be affected by soluble wastes associated with fin-fish
farming. Soluble wastes include ammonia, phosphates and dissolved organic
carbon emissions. The level of nutrient loads in the water column is influenced
by flushing rates at farming sites.
The Tasmanian regulatory regime establishes a permitted zone of impact
35 metres a lease boundary. Benthic composition may change due to elevated
organic loading of the sediments from excess feed and solid fish excreta. Pollution
tolerant species may come to dominate other species with the TSGA noting that
this will be visually obvious.
This chapter canvasses the evidence received in relation to waterway
health commencing with general comments and then addressing specific issues
raised in evidence: impacts of in-water net cleaning; broadscale impacts; and
the effects of hatcheries on rivers. Finally matters relating to threatened and
endangered species are addressed.
Waterway health in Tasmania
The Kingborough Council pointed to the importance of waterway health in
areas where fin-fish fishing operates. Mr Stephen Wass, Mayor, stated in
relation to the D'Entrecasteaux Channel:
It is regarded as one of the safest waterways in the state.
It not only provides a working area for the salmonid industry but is also a
working bay for other industries. And certainly as far as the community and
business go it is a recreational area. So from our perspective, the community's
perspective, it is very important that this waterway is maintained in a healthy
manner into the future so that all can continue to enjoy it. It is pleasing to
note that over the last number of years Kingborough Council, Huon Aquaculture
and Tassal have had a very good working relationship. Those companies have come
on board in relation to what is called the D'Entrecasteaux collaboration. That
collaboration aims at having people involved within the D'Entrecasteaux Channel
to come together to work to ensure that the waterway and all life that that
waterway supports will continue into the future.
Some submitters to the inquiry stated that there had been adverse
impacts on waterway health from fin-fish farming. For example, the Tasmanian
Conservation Trust commented:
The aquaculture industry in Tasmania is often represented as being
clean and green and a positive development for the environment. In fact this industry
has many negative effects on our environment, and these are going to become
even worse if the industry's planned expansion become a reality.
Mr Jon Bryan from the Trust added:
I think it should be obvious that the aquaculture industry
has environmental impacts. Fin-fish aquaculture in the marine environment as it
is done in Tasmania has significant impacts on the environment including loss
of amenity. These impacts are of concern to many. In some cases we believe that
environmental impacts may be serious enough to impact the aquaculture industry
Environment Tasmania stated that the marine environment may not be able
to cope with the expansion of fin-fish farming in south east Tasmania. It also commented
that there has been an increased number of community reports of toxic algal
blooms, declines in native fin-fish and shellfish numbers, algal epiphyte
growth smothering marine vegetation, and nutrients impacting on macroalgal
communities hundreds of metres away.
The Tasmanian Abalone Council stated that, in relation to the D'Etrecasteaux
...it is also commonly accepted now that the salmon industry is
a major contributor of anthropogenic effects in the lower channel in
particular, and so we have some concerns about their current practices and
those practices going forward. We have concerns primarily about the waste
The Tasmanian Abalone Council added that 'there is an underlying premise
that the surrounding ecosystems can assimilate and break down the waste'.
Other submitters commented that the waterway health of inland rivers had
also been adversely affected by salmon hatcheries.
Both the Tasmanian Government and the industry commented on the success
of the regulatory regime and farming practices to ensure waterway health in marine
lease areas. The Tasmanian Government pointed to the robust and adaptive
regulation of the industry which is designed to ensure the impacts on waterway
health and threatened and endangered species are identified and mitigated to
the extent of an acceptable risk. In addition, it was noted that environmental
impact statements, required for draft marine farming development plans (MFDPs),
must identify impacts on the environment and threatened and endangered species
as well as measures to mitigate the impacts.
The Tasmanian Government also stated that management controls contained in
MFDPs, and licence conditions contained in marine farming and freshwater fish
farm licences, provide mechanisms to manage the impacts of salmonid farming on
the environment. The Tasmanian Government concluded:
When considered in the context of other jurisdictions, it is
clear that the adopted approach for waterway management in Tasmania is world's
best practice, particularly in relation to management of stressors to water
The TSGA submitted that the impact of salmonid aquaculture on waterway
health is dependent on a number of factors, the nature and intensity of farming
and the capacity of the receiving environment to assimilate the impacts. Other
factors, such as natural catchment and oceanic inputs, also influence waterway
In relation to water quality impacts, the TSGA commented on both the
near field and broadscale. In the near field, 'the effect of feed input and
fish excreta at any salmonid farm is expected to result in localised
environmental impacts to water quality within and around a lease area'. In
relation to broadscale impacts on water quality, the TSGA stated that 'salmonid
farm derived nutrient inputs were not anticipated to result in significant or
broadscale effects to the water quality characteristics or ecosystem'. However,
further research is currently being undertaken.
In relation to benthic impacts, the TSGA commented that impacts on the near
field benthos are 'largely predictable and reversible' and added that the
deposition to the seafloor of excess feed and solid fish excreta is very well
It was stated that 'evidence from the BEMP in the Huon Estuary and
D'Entrecasteaux Channel show no evidence of effects on the condition of the
seafloor and faunal communities as a result of salmon farming'.
Nevertheless, the committee received evidence from submitters that expressed
concern about broadscale impacts. The issues they raised are discussed later in
Dr Adam Main, Chief Executive Officer, TSGA, commented further on
concerns about the impact of fin-fish aquaculture on waterway health. He stated
that the industry's position is that:
...the health of Tasmanian waterways reflects historical and
current marine and terrestrial influences from both natural and man-made
sources—not the least of which is a changing climate. We accept that we should
be part of the discussion regarding the health of Tasmanian waterways. We do
not, however, for one moment accept the oft-cited mantra—namely, that there is
a problem and we should be a part of it. We reject categorically that there is
The TSGA commented on the need for the industry to ensure waterway
health and stated:
Minimising the environmental impacts of marine aquaculture is
a common goal for regulatory authorities and producers because environmental
quality, growth and health of fish and farm profits are inextricably linked.
Internationally, many countries and independent global organisations have
developed aquaculture best management practices to improve the environmental
and financial performance of aquaculture operations.
Dr Main went on to note that the industry is highly visible, works
within a regulatory framework:
You can see our industry and, through the regulatory
framework, you can see everything that is happening within our industry. We are
out there to be looked at and to be judged, but, more importantly, we need
really good water to grow really good fish. If we do not have good water, we
will not be able to grow good fish. So we have those as push factors within the
companies. They know that, to manage a whole range of issues that affect other
places around the globe, we need to maintain our waterways, because that means
that we can grow good fish. We have been able to achieve that and demonstrate
The Tasmanian Seafood Industry Council concluded that:
In any consideration of the impacts of marine farming it must
be recognised as with any farming activity there will be an impact at least
[at] the local near field level. What must be taken into consideration is that
it is not in the best interests of marine farmers to alter the environment to
an extent that marine farming activities are compromised.
Issues concerning waterway health in Tasmania
As noted above, some submitters commented that the fin-fish aquaculture
industry was impacting adversely on waterway health in Tasmania. The following
discussion canvasses there major issues raised in evidence:
possible adverse impacts from in-water cleaning of nets;
broadscale impacts on rocky reefs in south east Tasmania; and
the effect of hatcheries on inland rivers.
Evidence relating to aquaculture activities in Macquarie Harbour is discussed
in chapter 6.
In-water cleaning of nets
Biofouling occurs on submerged surfaces when unwanted marine organisms
grow. In the fin-fish aquaculture industry, as the areas are used for intensive
production, large volumes of organic material such as leftover fish food and
faeces are a source of food for biofouling organisms. Biofouling occurs on the
infrastructure used in production including nets, cages, ropes, floats, boats
High levels of biofouling can lead to increased hydrodynamic drag,
reduced buoyancy, poor flow and low dissolved oxygen, resulting in increased
cleaning and maintenance costs. Depending on their composition, biofouling
communities can also harbour disease, toxins, Invasive Marine Species (IMS),
cause irritation and lesions in salmon, and adversely affect the caging and
Until recently, the fin-fish aquaculture industry used copper-based
anti-fouling agents to curtail biofouling. However, following concerns about
the environmental impact of copper, the industry has moved away from
copper-based agents. In-water cleaning operations have been introduced to
manage biofouling on fish cage nets. The industry uses in-situ Marine
Inspection Cleaner (MIC) technology for washing nets. This involves using high
pressure blasting or vacuuming to remove biofouling from the net surface of the
pen before it reaches mature stages or heavy growth. The TSGA noted that
'particulate organic matter is released to the environment through this process'.
The TSGA has produced a Best Management Practice guideline for in-water
cleaning which details net washing practices to reduce impacts on the marine
environment. The TSGA noted that ongoing research and monitoring is being
undertaken to further refine best practice in relation to:
general mass balance calculations around net cleaning emission
volumes and overall assimilation capacity;
updating the marine biosecurity and biofouling management plan
for the industry;
continual improvement of onsite surveillance and monitoring
programs and strengthening this in relation to natural seasonality; and
linkages to international work being undertaken around emission
capture and beneficial reuse.
The Tasmanian Government noted that net cleaning information is reported
to the regulator, in addition to a range of other information, and is used by
DPIPWE to determine monitoring survey specifications and focus monitoring
effort in appropriate locations within and outside operational lease sites.
Mr Graeme Woods, DPIPWE, added that monitoring activities:
...not only looks at the benthos or the sediment chemistry and
the organisms within the sediments but also involves very targeted underwater
video surveys. Those surveys are basically targeted at cage sites that have the
highest frequency of in-water cleaning. The idea there is to be able to detect
any potential effects from that activity underneath the cages and outside the
lease areas. To date we have not detected any substantial sedimentation effects
as a result of that cleaning activity.
The move away from copper-based antifouling paint on farming
infrastructure was acknowledged as a major change for the aquaculture industry
and had resulted in a significant benefit for the marine environment. Dr John
Whittington, DPIPWE, stated:
...it is really important to recognise what an innovation this
has been, because previous to in situ net cleaning the mechanisms for cleaning
nets and managing nets involved the use of copper based antifoulants, which
potentially have an impact on the environment. Moving to this technology has
significantly reduced the risk of environmental contamination by salmon farming
by essentially taking copper out of the system. So I think that is something
that really needs to be celebrated. It has also improved fish handling, because
there is a lot less movement in having to move fish around as nets are changed,
so I think there are some really good benefits there from both a production and
an animal welfare perspective.
The TSGA also commented that in-water cleaning has 'considerably reduced
the need for land based net cleaning and maintenance'. In addition to the
introduction of in-water cleaning, the TSGA stated that the progressive
introduction of new technology nets has resulted in a two-thirds decrease of
in-water net washing output.
However, a number of submitters commented negatively on the move to in
situ net cleaning.
For example, Biofouling Solutions Pty Ltd commented that there is the risk that
in-water net cleaning can facilitate the spread and proliferation of dislodged
viable biofouling organisms to the wider environment, and even the spread of
Biofouling Solutions recommended the development of an overarching Biosecurity
Management Plan, an appraisal of current in-water net cleaning operations and
surveillance and monitoring of IMS. Biofouling Solutions concluded:
The uncertainties and associated risks with current
biofouling and IMS management practices highlights the need for a critical
assessment of risks associated with net cleaning and a robust, independent
review of the biosecurity system requirements across the state of Tasmania.
Two seafood industry submitters, Dover Bay Mussels and the Tasmanian
Abalone Council, also commented negatively about the change to in-water
cleaning and its possible impact on waterway health. Dover Bay Mussels stated
that in-water net cleaning resulted in 'industrial quantities of fragmented
marine biofouling being introduced in to marine environment'. It was stated
that a major component of this fouling are hydroids, a member of the jellyfish
family, which have a hard chitonous exoskeleton that, when fragmented, release
large volumes of nematocysts (stinging cells) into the water. Dover Bay Mussels
stated that nematocysts are known to cause gill damage in the caged salmon. It went
on to comment that no studies have been undertaken into the potential impact of
nematocysts on the health of other marine organism gills. It was also stated
that studies show that, due to small particle size of net wash material, it
will spread far beyond the current 35 metre monitoring point.
Dover Bay Mussels concluded:
...this shift to In-Situ Net Cleaning although done with good intentions
has not had the potential impacts on the surrounding environment fully investigated,
it has evolved without any checks or balances and the risk for harm is real and
warrants further investigation before further expansion is allowed.
The Tasmanian Abalone Council commented that there is no requirement
that the waste (biofouling or equipment coatings) generated by in-water
cleaning is to be captured or removed from the marine environment. Previously,
nets had been cleaned onshore in semi-closed systems with waste being captured.
The use of in-water cleaning 'results in waste being deposited directly into
the marine environment and thereby removing the farms responsibility to capture
and process its biofoul by-products'.
Mr Dean Lisson, Tasmanian Abalone Council, commented that:
...the salmon industry here in Tasmania operates on this
premise that whatever waste products that go into the water—the waste from the
salmon itself, the uneaten feed pellets, the biofouling from the cleaning of
the nets; all of those things—will be assimilated by the environment and there
will not be any long-term detrimental effects on the environment.
In response to the industry's claim that in-water cleaning of enables nets
to be cleaned while relatively free of biofouling, thereby minimising waste,
the Council stated that this premise was 'flawed as previously the method of
removing nets for washing deposited very little waste at the lease site, so any
in-water cleaning methods increase the overall input into the environment'.
The Tasmanian Abalone Council recommended that the industry cease in-water cleaning
of equipment until waste capture technology is available and becomes a
Response to issues raised in
The TSGA responded to concerns about in-water net cleaning and stated that
cleaning is undertaken frequently to optimise fish health, lessen the level of outputs
that need to be assimilated by the sediment and surrounding environment, to prevent
the establishment and colonisation of potentially harmful species and to maintain
high levels of water flow and in cage environmental conditions.
The TSGA added that as a result of the high frequency of cleaning:
...tunicates, shellfish and colonising hydroids do not have
sufficient time between net cleaning events to become well established on net
surfaces. It is recognised in some literature that large volumes of fragments
of some hydroid species may have a detrimental effect on fish gills; this is a
different species of hydroid than is present in Tasmanian waters.
Dr Main concluded that:
We are confident that the impact of the net cleaning falls
within our farm footprint. We have a very defined farm footprint.
The TSGA also noted that a two year study investigating deposition of net
wash in and around leases and the hydrodynamics of various sites had been
undertaken. It was shown that there was minimal impact and net wash organics
were assimilated within lease space by natural benthic biological processes.
The TSGA went on to state that these findings are supported by data from annual
In relation to technology to capture debris from in-water cleaning, the TSGA
stated that it was following international research and development work being
undertaken on filter technology.
In addition, further research is being undertaken to determine the risk factors
associated with net cleaning.
Mr Graham Woods, DPIPWE, explained that the research is aimed at investigating
a range of concerns raised including those by Dover Bay Mussels. The research
is being undertaken by the Institute for Marine and Antarctic Science (IMAS)
and is a precursor to a wider research project investigating the effects of
salmon nutrient emissions on nearby reef systems and macroalgae communities.
This is discussed further in the following section.
Broadscale impacts of fin-fish
Submitters expressed concern that the impacts of the fin-fish industry
at the far-field or broadscale level were not adequately understood or
regulated. Dr Catriona Macleod, The IMAS, commented that a great deal of
research has been undertaken on what is generally called the broadscale effects
but these relate to water column interactions rather than reef or intratidal
The impacts on reef systems in the south east of Tasmania were raised by the
Tasmanian Abalone Council and Environment Tasmania.
The Tasmanian Abalone Council released a report in October 2014 in
response to plans by the salmonid industry to expand in to waters adjacent to
productive wild abalone beds. The report commented on a range of issues
including the potential for nutrient input from salmonid farming to affect the
structure and biodiversity of inshore oceanic reef communities; and the effect
of sediment from salmonid farming on abalone larvae and adult abalone.
The committee notes that the Tasmanian Government, on the day of the
committee's first hearing in Hobart, released a review by Professor Colin
Buxton on a report by the Tasmanian Abalone Council on the risks to the
Tasmanian abalone fishery from further expansion of the salmonid industry.
Professor Buxton's major findings were outlined by Dr Whittington who
...essentially, there was no evidence for a direct
cause-and-effect relationship between the loss of abalone productivity and salmon
farming. His report basically finds that there is no link between salmon
farming and abalone productivity. There is a whole lot of reporting around
that, but that is, essentially, the crux of it.
Dr Main, TSGA, also commented on the findings in Professor Buxton's
report and stated:
...it seems from my early understanding that it supports
exactly what I have just said: our impact is in our farm footprint. The risk or
the threat of in situ cleaning, or salmon farming output in general, does not
have that far-field effect. It is quite gratifying to have that validated...
The committee received other evidence which commented on the potential
impact of farming activities on reef health. Environment Tasmania, for example,
noted that 5,500 tonnes of feed can be used in one fish lease in south east
Tasmania. This corresponds to an input of 275 tonnes per year of nitrogen, of
which 41 tonnes is released into the environment. Environment Tasmania commented:
This represents a significant increase of nitrogen to sediments
and nearby reef and kelp communities. It is possible that the effects of this
increase in available nitrogen could lead to changes in reef ecosystem
structure, biodiversity, biomass and productivity, and more importantly impact
on the endangered and vulnerable species in the area. However there are no
monitoring programs established to monitor the impact of this significant
increase in nutrients on these ecosystems.
Environment Tasmania also provided the committee with a recently
published paper on the broadscale impacts of farming on macroalgal assemblages
on rock reefs in Tasmania.
Environment Tasmania noted that the findings included that:
the extent of the impact of dissolved wastes is poorly known both
in Tasmania and elsewhere;
nutrient enrichment from fish farms affects subtidal reef
communities to a variable distance, and at scales of hundreds of metres, but
given consistent findings from multiple sites, the most plausible
explanation for observed differences in algal communities is impact from the
release of nutrients from fish farms;
fish farms had a significant effect on benthic reef communities
at greater distances than regulatory compliance sites; and
ongoing nutrient enrichment from fish farms remains a potential
threat to macroalgal community structure and reef diversity through the
The TSGA responded to concerns about the possible impacts on rocky reefs
including the paper provided by Environment Tasmania. In relation to the paper,
the TSGA stated the paper is based on work completed in 2009 and information from
this work has been incorporated in a number of research initiatives in recent
The TSGA also commented that marine farming regulations prohibit the
siting of a fin-fish zone over a rocky reef. However, the TSGA stated that potential
broadscale impact of fin-fish farming on nearby rocky reefs has been recently
identified as a gap in knowledge. In response to this gap in knowledge, two
projects have been funded by the Fisheries Research and Development Corporation
(FRDC). The TSGA noted that the research will be aimed at addressing the
concerns raised by the Tasmanian Abalone Council, Environment Tasmania and
....[it] has been framed with the specific intention of addressing
key concerns of industry (both aquaculture and fisheries), regulators and other
stakeholder groups on how finfish farming in new areas could change
environmental interactions...the purpose of the research is to evaluate the
potential for interactions between local reef systems and salmon farming, and
recommend industry and Government appropriate monitoring and assessment
approaches based on risk mitigation strategies.
The first will investigate the broadscale interactions of salmon farming
with reef systems through sediment deposition and nutrient dispersion,
including the development of risk appropriate approaches for assessment and
monitoring of reef health. The IMAS, the Tasmanian Abalone Council, the rock
lobster industry, the recreational fishing industry and the salmon industry are
collaborating on the study.
Dr Macleod informed the committee that there will be steering committees
that comprise the stakeholders as well as a community reference group and a
science reference group. Dr Macleod commented that:
...we are actively trying to engage with the broader community
to explain to them what the research is going to be doing and get feedback from
them as to whether it is addressing the issues they would like to see
addressed. I have to acknowledge to the community that we cannot potentially
address every issue, but where we can we will try to transfer the information
back to them that is relevant to the issues of concern.
But also, most significantly out of this, the scientific
reference committee as part of this project is something I am really
enthusiastic about, because it will allow us to engage with other scientists
working in and around the area, which is something that is often not done with
research projects going forward—scientists who may not be part of the active
research project but have very valuable insights and information about the
areas we are researching. We are really excited about that project kicking off.
The IMAS is also undertaking analysis as a precursor to this study with
the aim to determine whether there have been any broadscale changes associated
with the development of the salmon industry at Tinderbox and Ninepin Points.
Further information on the study was provided at the Budget Estimates in
May 2015 by the FRDC. The FRDC stated that the project had been identified as a
'high priority'. In relation to outcomes, Mr Patrick Hone, Executive
Director, FRDC, commented:
Like all science, that is an uncertainty. This is a process
to look at a range of questions that we have in salmon farming, particularly
because, as many people would be aware, it is a continually expanding
development. We have to keep up in terms of that expansion to make sure that
the increasing biomass of salmon is consistent with the ability of the environment
to be resilient in terms of how it will respond. They are also now expanding
into areas that they had not done previously. As you are probably aware, they
are going into much more deeper, exposed environments. These are areas in which
we previously had not done research. So we are testing a whole lot of new
hypotheses about dispersion, impact, down-stream currents, et cetera.
Mr Hone went on to state that environmental research will continue for
many years and concluded that:
Our feeling is that this will also result in some significant
policy changes. But there will be more policy questions that will come forward
and that will require an ongoing environmental research program.
The Tasmanian Conservation Trust welcomed the study but commented that
it 'should have been carried out before aquaculture expansion was permitted to
occur to the extent that it has'.
The Tasmanian Seafood Industry Council also commented on these research
projects. Mr Julian Harrington stated that in the Council's view:
...where it is demonstrated that fin-fish farming activities
are having an unacceptable negative impact on the activities of other
stakeholders who have access to Tasmania's marine resources and/or an
unacceptable impact on the broader marine environment, then fin-fish farming
practices must be altered to alleviate any impacts.
In addition, the TSGA stated that while early work on macroalgal
communities found that there were no trends in macroalgae communities that
could be attributed to fish farming in the area, the industry has funded a two
year study aimed at characterising the status and health of macroalgal
communities in south east Tasmanian waters.
The committee received evidence on the long-standing concerns about the
impact on the health of inland river waterways from hatcheries.
Fresh water hatcheries produce smolt for deep water farms. They are
either flow-through, that is they use river water, or recirculation hatcheries.
The Environment Protection Authority (EPA) noted that recirculating aquaculture
systems provide better control over fish growing conditions and use
significantly less water (compared to flow-through systems). When their wastes are
managed by beneficial reuse (for example, sustainable irrigation on
agricultural land) emission of nutrients to waterways is avoided.
The Tasmanian Government provided the committee with information on an
environmental review of inland fish farms to be undertaken by the EPA:
In 2014, in light of the ongoing expansion of the salmon
industry and the subsequent increase in production and development at the
inland fish farms to meet demand for smolt, an environmental review of the
large scale inland fish farms is being conducted by the Environment Protection Authority
Division and Inland Fisheries Service, beginning with a review of the
regulatory conditions and environmental performance of existing activities.
The purpose of the review is to assess current environmental
performance and review existing environmental regulation of these activities.
Following review of the existing activities the Environment Protection
Authority Division will then review the regulatory framework for these activities
in a consultative process with stakeholders.
The Tasmanian Government went on to state that the Inland Fisheries
Service and EPA continue to actively deal with water quality management in new
farm licences, renewals and to address issues raised about the hatcheries.
A number of submitters commented on the Huon Aquaculture hatchery on the
The original hatchery on the Russell River was purchased by Huon Aquaculture in
2006. It was argued that the hatchery releases nutrient rich water into the
Russell River which results in a decline in water quality below the hatchery
including algal growth.
In addition to concerns about water quality, Ms Vicki O'May commented that the numbers
of native endemic marine species, including water rats and platypus as well as
nymph, dragon fly and other insect life, have declined on the river.
Huon Aquaculture responded to concerns raised in submissions and noted
that the Lonnavale Hatchery on the Russell River is operated under Tasmanian
Government regulation. Huon Aquaculture provided the committee with a detailed
response to comments in submissions and noted that a study of the health of the
Russell River had recently been undertaken. The study found that:
There therefore appears to have been no major negative impact
of the raised algal levels on the fauna of the Russell River. The overall
ecological impact therefore appears slight. Any management decision with regard
to controlling algal density through management prescriptions at the Huon
Aquaculture site should be made in this light.
The TSGA also responded to concerns about hatcheries and stated that the
industry is committed to the responsible management of all its freshwater
operations. The TSGA refuted claims that there is no independent monitoring of
hatchery facilities and stated that the industry undertakes extensive
monitoring to ensure it meets rigorous environmental standards as required by
In relation to comments in submissions about the presence of algae, the TSGA
observed that algae has been detected both down and upstream of freshwater
hatcheries in the Huon and Channel area. It added that it 'is important to note
that there are a variety of inputs into these freshwater systems and the
industry continues to carefully monitor its contribution and work within the
The TSGA concluded that flow-through hatcheries are still playing an
important, but transitioning, role in the salmonid industry with the industry
currently undertaking large investments in new constructing new, state of the art
The committee acknowledges the importance of ensuring the health of
Tasmania's waterways in areas where fin-fish farming is undertaken. The
committee notes that operating practices have changed over time to ensure that,
as more information emerges on the effects of the fin-fish industry on the
marine environment, waterway health is maintained. This is a result of the
industry's commitment to ensuring its continued sustainability and limiting its
impact on the marine environment and the Tasmanian Government's commitment to a
robust adaptive management framework.
One area of change has been the industry's move away from copper-based
paint to control biofouling. This is a welcome change to fin-fish operations
and will decrease the amount of copper contamination of the marine environment.
While there are concerns about in-water cleaning practices, the committee notes
that there is ongoing research, and modification of farm activities, to ensure
that any impacts from in-water cleaning on the marine environment are within
The committee notes the concerns raised by some submitters about the
lack of adequate knowledge about broadscale interactions, particularly on rocky
reefs. The committee considers that demonstrated adverse effects on far-field
marine environments arising from fin-fish farming operations would not be an
acceptable outcome for the environment or other aquaculture industries, such as
the abalone industry, which are reliant on the health of Tasmanian waterways.
However, at this point in time, it remains unclear that adverse effects are
occurring in rocky reef environments or that any observed changes are the
result of fin-fish farming activities.
The committee welcomes the research which is now underway to address the
concerns about the lack of knowledge of broadscale interactions. The research
involves many stakeholders in the industry, including the Tasmanian Abalone
Council. The committee notes the engagement with the broader community in the
research process. The committee is confident that, should it be demonstrated
that there are unacceptable negative effects from fin-fish activities, the
adaptive management regulatory regime will ensure that rocky reef environments
are protected and that appropriate monitoring and management controls for the
fin-fish industry are developed and implemented.
In relation to freshwater hatcheries, an environmental review of large
scale inland fish farms is currently being undertaken by the Tasmanian Environment
Protection Authority. In addition, the committee notes the outcomes of the
recently completed study of concerns arising from farming activities at the
Russell River hatchery. The committee has confidence that work to be undertaken
by the Environment Protection Authority will inform future policy making in
relation to inland hatcheries.
Threatened and endangered species
Evidence was received on the impact of the fin-fish industry on
threatened and endangered species. Threatened and endangered species are listed
under Commonwealth and Tasmanian state legislation.
The Environmental Protection and Biodiversity Conservation Act 1999 (EPBC
Act) gives the Commonwealth Government responsibility for listed nationally threatened
species and ecological communities as a matter of national environmental
significance. Threatened species also receive protection through the protection
of other matters of national environmental significance, for example, where
they occur in protected areas such as world heritage properties, national
heritage places, Ramsar wetlands, Commonwealth marine areas and the Great
Barrier Reef Marine Park.
The EPBC Act requires the responsible minister to establish a list of
threatened species divided into the following categories:
extinct in the wild;
Once listed, threatened species and ecological communities (except
ecological communities listed in the category of 'vulnerable') are recognised
as a matter of national environmental significance. Consequently, any action
that is likely to have a significant impact on listed threatened species and
ecological communities under the EPBC Act must be referred to the minister and
undergo an environmental assessment and approval process.
Marine species listed under the EPBC Act, in the areas where aquaculture
activities take place, include Australian and New Zealand fur seals, Maugean skate
(listed as endangered) and spotted handfish (listed as critically endangered).
In addition, a number of birds are listed.
The primary Tasmanian legislation is the Threatened Species
Protection Act 1995. This Act lists a number of marine species including
numerous coastal or oceanic bird species, four whale species, three seastar
species, the spotted handfish, the Gunn's screwshell and the Maugean skate. A range
of measures to protect listed threatened species are set out in the Act and
makes it an offence to take a listed species without a permit.
In addition, regulations made under the Tasmanian Nature Conservation
Act 2002 list 'Specially Protected' or 'Protected Wildlife'. A large number
of marine mammals and coastal or oceanic bird species are listed as either
Specially Protected or Protected Wildlife. The protection of a number of fish
species, including five shark species and all handfish species that occur in
Tasmania, is provided for under the Fisheries (General and Fees) Regulations
2006. Freshwater species are listed and protected under the Threatened Species
Protection Act and the Inland Fisheries Act 1995.
The TSGA commented that the industry continues to support research to
understand the potential impact on identified endangered and threatened species
not only within the Macquarie Harbour system, but all areas where farming
activities occur. The TSGA went on to state:
The regulation of salmonid farming in Tasmania is robust and
adaptive to ensure that the impacts on waterway health and threatened and
endangered species are identified and mitigated to the extent of an acceptable
The IMAS also commented that interactions with threatened and endangered
species have largely been addressed through zone assessments and appropriate
However, the committee received evidence which raised issues in relation
to threatened and endangered species. The following discussion canvasses the
evidence received in relation to:
fur seals; and
The Australian Marine Conservation Society stated that the Maugean skate
is a rare and endemic species which is only found in Macquarie Harbour and
Bathurst Harbour. It is adapted to low nutrient and low salinity environments
of the harbours.
Environment Tasmania added that the Maugean skate has 'the oldest lineage of
skate in the world and the only one of its kind worldwide to occur mainly in
brackish water, and with such a highly restricted distribution'.
Submitters expressed concern about the impacts of the current level of
aquaculture activities and proposed expansion fish farming activities in
Macquarie Harbour. These concerns included the impact of increased nutrient
levels, changes in the dissolved oxygen levels, and increased sedimentation;
and the low population levels of the Maugean skate (estimated at only 2,500).
EDO Tasmania commented that environmental organisations raised concern
that not enough was known about the ecology or biology of the Maugean skate, or
the likely movement of nutrients within Macquarie Harbour, to ensure the
species would not be significantly impacted by the expansion of aquaculture
activities in the Harbour.
The TSGA responded that the industry had identified, in the original Macquarie
Harbour environmental impact statement, that Maugean skate was a species of
interest requiring further research.
Concerns regarding the potential impacts on the skate from aquaculture
activities have led to the commissioning of a FRDC-funded project that to
examine the movement, habitat utilisation and population status of the skate in
Macquarie Harbour. The IMAS provided the committee with an overview of the
project and commented that acoustic tagging has been used to track the movements
(location and depth) of both skates and escaped salmonids. The project is providing
data on the biology, ecology, habitat preferences, and environmental sensitivities
of the Maugean skate that can be used to not only understand the potential risks
to the species associated with salmon farming but also to provide a better understanding
of other environmental risk factors.
The IMAS went on to note that one concern was that fishing (gillnetting)
in the harbour may have an adverse effect on the Maugean skates, and because
one of the main species targeted in gillnet fishing is salmonid escapees, the
study will evaluate strategies to reduce the probability of encountering skates
The preliminary findings of the project indicate that some Maugean skate
move widely throughout Macquarie Harbour, while others appear to be more site attached
and the vast majority of their time is spent in the six to 15 metre depth
range, although some individuals moved into deep or very shallow water.
Environmental data collected as part of the project are being analysed to
examine how factors such as salinity and dissolved oxygen influence patterns of
behaviour. IMAS noted that, although population size estimates are not yet
available, it is clear from the catch rates that the population is substantially
larger than the approximately 1000 individuals suggested in the past.
The TSGA commented that the project findings indicted that detections of
Maugean skate in depths greater than about 25 metres, which is the depth of the
harbour in which the majority of the farms are located, were rare.
Further, that 'early results indicate that salmon farming is having no
significant impact on the skate'.
Dr Donald Ross, IMAS, indicated that it could not categorically be
stated that the skate were not at risk. He went on to point to the developments
in technology which will assist in greater understanding of skate and its
One of the exciting things with that technology is that those
acoustic tags can track where they are but they can also measure some environmental
parameters. A company has just come out with a tag that measures oxygen so it
can transpond the oxygen concentration back. They are looking at putting these
tags on skates so we will actually be able to tell what environment skates are
sitting in. It is pretty much cutting edge technology that is being brought to
Tasmania to look at skate behaviour for that very reason.
The Australian Marine Conservation Society commented that the spotted
handfish is listed as critically endangered under the EPBC Act. The Society
commented that the spotted handfish is potentially affected by farming
activity, but 'there is limited understanding of the extent of impact due to a
lack of monitoring' and stated the impact of salmon farming on this species
warrants further and immediate investigation.
The TSGA responded to concerns about the impact of farming activities on
the spotted handfish. The TSGA stated:
They are known to prefer inshore demersal habitats within a
depth range of approximately 5 to 15 metres, and they have a limited and often
fragmented range linked to habitat preference. Recently the handfish, was found
within one fish farm lease in the lower D'Entrecasteaux Channel, a region in
which the handfish was no longer thought to exist. There is no current evidence
that the industry either positively or negatively impacts on the handfish.
Through annual monitoring programs the industry is well placed to provide
further data on this important group of fish.
Fur seals are listed as a protected marine species under the EPBC Act. The
Tasmanian fin-fish industry has had to manage its interactions with Australian
and New Zealand fur seals in south east Tasmanian since its inception in the
mid-1980s. Mr Jon Bryan, Tasmanian Conservation Trust, explained to the
There is a fundamental problem with seals and the aquaculture
industry. To put this in context: a seal looks at a salmon like a cross between
heroin and a 'big mac'. They just love salmon.
A number of submitters raised concerns regarding the relocation of seals
and killings of seals by the Tasmania salmonid industry. The Australian Marine
Conservation Society commented that 'there have been persistent fur seal deaths
due to interaction with aquaculture operations in the southeast region either
through accidental drowning in farming nets, or deliberate killing by operators'.
Problem seals are also relocated. However, the Tasmanian Scalefish
Fisherman's Association (TSFA) also stated its main concern as:
...the practice of relocating rogue seals from the precincts of
fish farms to other waters. These rogue seals have commonly been relocated to
the North coast and usually in places of easy access with special attention
given to the ease of unloading the seals. Invariably these places have been
adjacent to commercial scale fishermen's areas of operation.
The TSFA commented that relocation of seals 'partially solves a problem
for the aquaculture industry but creates a problem for the wild catch
fisheries' and it suggested 'rather than move the problem, perhaps a more
permanent solution may be found by euthanizing the problem seals – much the
same as farmers being able to conduct vermin control'.
In response to the TSFA's suggestion to euthanize seals Tassal stated:
Tassal is dismayed by the suggestion that euthanizing seals
is a solution to the issue. In August 2011, as part of our partnership with WWF
Australia, Tassal agreed to cease euthanasia of seals (unless in extreme
circumstances and safety of staff is at risk).
According to Tassal, seal relocation sites are chosen and regulated by
The committee heard evidence from Mr Bryan, Tasmanian Conservation
Trust, in which he rejected 'the idea of killing seals or relocating them' as
it avoids 'the fundamental problem, which is breaking that link between cages
and food and seals'.
The Tasmanian Conservation Trust also observed that a number of fish
farming companies have effectively implemented cage technology to keep seals
out of the salmon pens. The Trust stated that:
Tassal, Huon Aquaculture and Van Diemen Aquaculture all have
effective cage technologies and fish handling procedures that can be used to
keep seals away from fish...there should also be a requirement for all farms to
use appropriate cage technologies and fish handling procedures to prevent
unwanted seal interaction. This will reduce the chance of seals continuing to
associate fin-fish farms with food and make it easier for all farms to deal
with this problem.
Mr Bryan, Tasmanian Conservation Trust, went on to comment that:
...I am absolutely enthusiastic about the industry's approach
to this. My understanding is that Tassal—certainly; and I think Huon—have said
they are no longer going to approve routine killing of seals. Van Diemen
aquaculture has a system cage technology which seems to be pretty good at
keeping seals away. I am very impressed with the work that is being done and I
would encourage them to keep our seals safe and keep their workers safe by
breaking that link between the seals and the food.
The TSGA commented that 'significant time and expense has been devoted
to better understanding' the behaviour of seals as well as 'designing and
installing netting systems that minimise interactions and impacts on both seals
Huon Aquaculture stated that is its seal and bird-proof pens are being
rolled out across farms in southern Tasmania. Huon Aquaculture stated that 'the
new pens are world first in seal protection that will deliver unparalleled
Tassal outlined in its Sustainability Report 2014 that its exclusion
measures include the use of KikkoNet, K-Grid nets, seal proof bird nets and
seal jump fences. In addition to these measures, Tassal's Senior Wildlife
Management Officer 'conducts regular rigging audits of pens at each farming
lease to ensure maximum exclusion capability'.
Petuna noted that its pen and net management has resulted in zero cage breaches
by seals for the past three years. Petuna has a policy of no lethal interaction
and does not routinely practice seal relocation. Petuna stated that there had been
no seal fatalities in the past 16 years.
The Tasmanian Seafood Industry Council were also supportive of the
efforts of the salmonid aquaculture industry to manage seal interactions, as it
Industry has spent considerable time and effort in
understanding seal behaviour so that net systems can be modified to minimise
interactions with the seals and to avoid additional stress on the fish that is
caused when a seal gains access to a pen, not to mention fish mortalities. The
industry reports out to the regulator and wider community on interactions with
The committee notes the FRDC is currently funding research for the
development of innovative seal exclusion technology.
The risks to birds from aquaculture operations vary but include
entanglement, loss of foraging habitat, behavioural change (for example,
increased scavenging by raptors), disturbance reducing breeding success, and
potential disturbance from noise, lighting, waste and vessel movements
associated with daily and nightly operations.
Birdlife Tasmania commented that, with the exception of the Great
Cormorant and Little Black Cormorant, all species of seabirds in Tasmania are protected
under the Tasmanian Threatened Species Protection Act and associated
regulations and many are also listed as marine and/or migratory species under
the EPBC Act. Birdlife Tasmania went on to comment that some birds involved in
entanglements and/or that died as a consequence could be reasonably be expected
or inferred to be EPBC-listed species.
In addition, Birdlife Tasmania noted that the Tassal Sustainability
Report 2013 stated that 498 Great Cormorants had been shot by Tassal at
Russell Falls and Macquarie Harbour during that year. Birdlife Tasmania
BirdLife Tasmania opposes any form of wildlife control such
as shooting, and has raised our concerns regarding this report and the broader
issue of seabird entanglement with Tassal over a number of years.
Birdlife Tasmania also commented that the behaviour of gulls in the south
east had changed and many were present at aquaculture facilities. As a
consequence, there are bird entanglements with nets. While noting that Tassal
and Huon Aquaculture have made efforts to reduce interactions between seabirds
and their infrastructure, Birdlife Tasmania stated that it was aware that the
numbers of entanglements have been in the hundreds for a species in a calendar
year, 'representing a significant proportion of the regional population'.
Birdlife Tasmania also commented that it had obtained data from DPIPWE on gull
management and control measures under a Right to Information request but had
yet to analyse the data.
BirdLife Tasmania has been involved with both companies, either directly
or through consultants, in the provision of data and advice on minimising the
risks to threatened and endangered species listed under the Tasmanian and
Commonwealth legislation that have been recorded within five kilometres of a
lease or proposed lease site. The species assessed were the raptors such as the
Wedgetailed and the White-bellied Sea-eagles, seabirds such as the Shy
Albatross and woodland birds such as the Forty-spotted Pardalote and the Swift
Birdlife Tasmania explained that :
For each identified species/threat combination, the threat to
the species was identified and mitigation or minimisation measures were
identified. In most cases, the risks were assessed as low, but for some species
novel threats were identified arising from the use of strong lights used to
illuminate facilities at night. Strong lights present a potential risk by
disorienting birds, resulting in an increased risk of collision with facilities.
Altering the lighting regime and reducing light spill outside of the facilities
is likely to reduce the potential to disorient flying birds.
Tassal reported on bird entanglements, including deaths, in its Sustainability
Report 2014. It was stated that:
There has been an overall steady improvement in regard to
bird interactions and welfare outcomes since reporting began in April 2013. The
implementation of our Seabird Rescue Strategy has enhanced welfare outcomes for
the rare cases where birds require care.
The committee acknowledges the efforts of the Tasmanian fin-fish
industry to proactively manage its interactions with threatened and endangered
species. The industry is currently undertaking research into Maugean skate and
has introduced management programs and changes to fish farm infrastructure to
limit bird entanglements.
In relation to seals, the evidence presented to the committee indicates
that the development and implementation of new pen and net infrastructure is
the most effective solution for the fin-fish industry to deal with seals, as it
reduces the industry's reliance on relocating problem seals. The industry's
investment in the development of new pen and net infrastructure to reduce the
number of seal interactions is welcomed. In addition, the industry now does not
euthanize seals unless in exceptional circumstances.
In relation to bird interactions, the committee notes that some
information is available from individual companies. However, more complete datasets
are held by the regulator. The committee considers that there should be greater
access to information on bird interactions. This information would fall within
environmental information which the committee believes should be more freely
available (see Recommendation 1).
The committee received submissions which commented that aquaculture
activities contributed to large amounts of marine debris. Marine debris from
aquaculture operations includes:
black hard plastic shavings from pipe modifications;
black plastic feedpipe;
treated pine and other timber;
polystyrene filled buoys;
general debris discarded by workers.
Submitters noted that debris from farming activities was not only
unsightly but also posed a threat to wildlife through ingestion or
Environment Tasmania commented:
Marine debris from fish farm activities has been a
significant concern for many local residents, waterway users and
conservationists for years. Death caused by entanglement in fish farm nets and
long ropes is difficult to assess on an individual lease by lease basis but
which, when regarded in accumulation, is having a significant and unacceptable
The TSGA provided the committee with information on the amount of marine
debris collected in 2012–13 and 2013–14. This is at table 4.1.
Table 4.1: Marine debris clean-up
Volume of rubbish
% attributable to salmonid
Source: Tasmanian Salmonid
Growers Association, Submission 33, p. 18.
The TSGA noted that the industry's clean-up activities also removed
debris which could not be attributed to fish farming operations and this
accounted for approximately 15m3 of
the debris collected each year.
Tassal's Sustainability Report 2014 also commented on the amount of
debris collected and stated that, in relation to its outcomes for debris
The increase in the percentage of rubbish attributable to salmon
farms is the result of a focused effort by Tassal staff to clean up historic
debris in the upper reaches of Macquarie Harbour, an area which has not
previously been undertaken for clean up.
Industry response and engagement
The TSGA commented that each company has implemented a waste mitigation
strategy in order to reduce the amount of debris that enters the marine
environment from farming operations. In particular, the companies have focused
mitigation strategies on reducing rope and feed pipe debris.
The TSGA went on to state that the industry has a 'rapid response'
philosophy when it is notified of debris irrespective of its origin. Broadly,
strategic objectives are to:
develop clear, rapid response plans when marine debris is
reported in the vicinity of fish farms;
achieve zero material waste entering the environment;
establish procedures and operating mechanisms that focus on
managing the loss of farm materials into the marine environment;
establish chains of responsibility at the farm level;
establish monitoring procedures;
conduct regular marine debris clean-up efforts in the vicinity of
fish farms; and
identify equipment to drive accountability.
In relation to the objective of zero material waste entering the
environment, Dr Main commented it was part of the industry's continuous
improvement program. The industry was using information gained during clean-up
operations to enable it to more quickly respond to debris issues and to achieve
the target of zero marine debris.
The companies also manage marine debris through a variety of community
Tassal, in its Sustainability Report 2014, commented that 'marine
debris has been highlighted by stakeholder materiality assessments as one of
the most important issues for the salmon farming industry to solve'. The report
went on to comment that the 'Adopt a Shoreline' approach was continuing and
'modest results from the implementation of farm level waste mitigation plans
were being seen'. Tassal indicated that while clean-ups will continue to be undertaken,
the company would focus on improving site ownership of the debris issue by
holding farm staff workshops and increasing staff engagement in community-based
marine debris clean-ups.
Huon Aquaculture's marine debris policy has been developed to reduce the
impact of activities on the marine environment. Huon Aquaculture undertakes collections
of marine debris at the request of the community, regardless of source and is
actively reducing marine debris from entering the waterway.
Huon Aquaculture also provides information on its clean-up locations on the
Huon River and D'Entrecasteaux Channel on its Sustainability Dashboard.
BirdLife Tasmania also noted its involvement with Tassal in relation to
marine debris. The industry undertakes to retrieve marine debris from
aquaculture operations from nearby foreshores in the D'Entrecasteaux Channel.
Birdlife noted that these collections can potentially impact on nesting birds
if the collection is undertaken during the breeding season (October to March,
inclusive). As a result of BirdLife Tasmania's presentation to Tassal staff, and
ongoing interactions with Tassal management, clean-up and debris retrieval
operations were shifted to winter months, which is the non-breeding season for
Similarly, Huon Aquaculture addresses marine debris issues through
toolbox meetings, training and internal communications to educate all staff on
marine debris, including identifying all types of rope used across its marine
operations. The TSGA noted that Huon Aquaculture identifies and records all
marine debris attributable to its operations and other sources including
household waste and other waterway user waste on clean-ups conducted both
internally and through community partnerships.
The Tasmanian Regional NRM Organisations also commented on its ongoing
engagement with industry across a range of issues including on-ground marine
debris clean-up and control projects.
However, while acknowledging that individual companies conduct
clean-ups, Environment Tasmania stated that these were only on an irregular
basis and that marine debris 'is a persistent problem that appears to require
Ms Sarah Lowe also argued that further funds are need for community-based
clean-ups and went on to state:
Policy regards marine debris at both Tassal and Huon
Aquaculture is to be commended with dedicated staff at the coalface often
endeavouring to appease angry community members lambasting marine debris from
farms. While both companies' websites promote community consultation it is
often difficult to contact community engagement officers who have a range of
priorities to attend to.
The Tasmanian Conservation Trust pointed to the litter washed ashore in
the vicinity of fish farms, particularly the southern shore of Macquarie Harbour.
The Trust concluded that fin-fish farms should make a greater effort to prevent
litter from leaving lease areas and cleaning up their litter on foreshores.
Marine debris is a significant problem in all Australian marine waterways.
While the fin-fish aquaculture industry already undertakes activities to reduce
the amount of debris entering Tasmanian waterways, the committee encourages the
continued exploration of new ways to decrease marine debris attributable to
aquaculture. In particular, the committee considers colour tagging of each
company's ropes and nets would enable identification of the source of marine
debris and provide information to aid debris reduction efforts.
The committee notes that much marine debris is not attributable to the
fin-fish industry and that the industry assists communities through a number of
programs to undertake clean-up activities. However, further expansion of the
industry's support for community-based clean-up activities would greatly
benefit the marine and coastal environment as well as contribute to the
building of goodwill in local communities.
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