ADVICE TO THE MINISTER FOR PRIMARY INDUSTRIES …dpipwe.tas.gov.au/Documents/Okehampton Bay salmo… · · 2017-02-16SALMON FARMING OPERATIONS OKEHAMPTON BAY ... East Coast waters

Great Oyster Bay and Mercury Passage Marine Farming

Development Plan October 1998 (as reviewed in 2007)

ADVICE TO THE MINISTER FOR PRIMARY INDUSTRIES

AND WATER

ON

SALMON FARMING OPERATIONS

OKEHAMPTON BAY

REPORT OF THE MARINE FARMING PLANNING REVIEW PANEL

FEBRUARY 2017

1

Introduction

This report was prepared by the Marine Farming Planning Review Panel (the Panel) in

response to a direction issued to it by the Minister for Primary Industries and Water under

section 9(1)(e) of the Marine Farming Planning Act 1995 dated 11 August 2016 relating to

proposed salmon farming operations at Okehampton Bay in the Great Oyster Bay and

Mercury Passage Marine Farming Development Plan area.

On receiving the direction, the Panel advertised publicly for submissions that addressed the

Terms of Reference (ToR). A Public Notice appeared in the Mercury on the 27 August 2016

and was replicated on the Glamorgan Spring Bay Council website as well as appearing in the

September edition of the Sorell Times. A four week period was allowed for the receipt of

submissions.

Additionally, the Panel requested submissions from Tassal Operations Pty Ltd, IMAS,

CSIRO and the Planning Authority (Secretary - DPIPWE). In preparation of the report,

information was also obtained through personal communication with officers in DPIPWE,

IMAS, Tassal and Aquenal Pty Ltd.

Almost 6,000 submissions were received, however the majority did not specifically address

the terms of reference of this inquiry.

The report presents a discussion of and advice in relation to each of the three terms of

reference.

The report also presents a summary of those issues raised in the submissions that did not

specifically pertain to the terms of reference in the direction issued however, commentary is

provided in relation to some of the more relevant issues.

2

The Direction

I, Jeremy Rockliff, Minister for primary Industries and Water, acting in accordance with

section 9(1)(e) of the Marine Farming Planning Act 1995 hereby determine that the Marine

Farming Planning Review Panel is to provide me with advice on the following

I. The environmental science supporting the proposed environmental monitoring and

management of salmon farming at Okehampton Bay within the Great Oyster Bay and

Mercury Passage Marine Fanning Development Plan October 1998 (as reviewed in 2007)

area: and

2. The adequacy of the environmental baseline data and surveys to allow the Director,

Environment Protection Authority to establish a contemporary environmental management

regime for the proposed marine farming activity; and

3. The adequacy of the Great Oyster Bay and Mercury Passage Marine Farming Development

Plan 1998 to allow for the implementation of a contemporary environmental management

regime for proposed salmonid marine farming at Okehampton Bay.

In providing its advice the Panel is to seek public and expert submissions, including a

submission from Tassal Operations Pty Ltd, on the above matters, and may conduct hearings

in accordance with section 9(2) of the Act, should it believe it is appropriate to do so.

The Panel is to provide its advice in the form of a written report.

The Panel is to provide me with the report by 28 February 2017

Jeremy Rockliff MP

Minister for Primary Industries and Water

Date: 11/08/2016

3

Findings in relation to ToR 1

The adaptive management protocols developed through this research are sufficiently flexible

that they could be applied to any site around Tasmania.

The Panel noted that the monitoring and management of impacts of salmon farming in

Tasmania is considered to be world best practice.

The Panel formed the view that the research underpinning the understanding, monitoring and

adaptive management of the impacts of salmon farming would be applicable to Okehampton

Bay and as a result is of the opinion that the current environmental science supports the

proposed environmental management and monitoring of salmon farming in Okehampton

Bay.


The Panel formed the view that the initial Baseline Data for Proposed Marine Farm Zones in

Great Oyster Bay (DPIF 1998) was fit for purpose and that the subsequent Baseline

Environmental Assessment of Marine Farming Lease #236 at Okehampton Bay (Aquenal

2000) was more detailed than the zone assessments undertaken by IMAS under contract to

DPIPWE to support new or amending existing marine farming development plans (MFPDs).

The latter zone assessments are undertaken prior to any new development (or zone extension)

being approved, and provide a broad characterisation of the seabed in the area of focus; these

include photographic, acoustic, biological, and sediment sampling.

However, the baseline surveys of Okehampton Bay, while sound in terms of method and

adequate for their purpose, are nevertheless more than 16 years old. As such they may not be

an up-to-date representation of “pre-farming” conditions. East Coast waters have been

gradually warming for the last 60 years due to climate change and the East Australian Current

extending further south (Ridgway 2007). It is predicted that the East Coast waters will

continue to warm (Hobday and Pecl 2014, Popova et al. 2016). IMAS (2016) note that whilst

is it unlikely that the specific topography of the development area would have changed

markedly over this time, more contemporary data with respect to the interactions with

threatened and endangered species and an update of habitat and hydrodynamic information

using the latest techniques is advisable. This will ensure that a true baseline is established

against which to measure any changes going forward. Clearly the original baseline surveys

in 1998 and 2000 would then serve as useful historical benchmark against which to consider

any longer term temporal changes.

The Panel is of the opinion that whilst the existing environmental data may well be adequate

to allow the establishment of a contemporary environmental management regime, it agrees

with the IMAS assessment and recommends that a further baseline assessment should be

carried out prior to the commencement of farming and prior to the establishment of the

management regime. This way no questions will subsequently arise as to the adequacy of the

data being used to assess the impacts of farming on the environment.

4

The Panel accepted the argument that more information on baseline assessments and other

environmental data were not freely available and noted that greater transparency would

improve community confidence in the sustainability and management of salmon farming.


Subject to the nitrogen input issue being addressed, the Panel is of the opinion that the Plan

and its supporting management framework will set out best practice and allow for a

contemporary environmental management regime for salmonid farming in Okehampton Bay.

For the Okehampton licence, the IMAS submission refers to specific licence conditions being

imposed to require more recent baseline and additional broadscale water quality and reef

interaction monitoring to address the key environmental management concerns. The Panel is

of the view that this can be achieved under the existing management controls.

5

1. The environmental science supporting the proposed environmental

monitoring and management of salmon farming at Okehampton Bay

within the Great Oyster Bay and Mercury Passage Marine Farming

Development Plan 1998 (as reviewed in 2007) area

Background

Open cage salmon aquaculture is a significant point source of nutrients to the marine

environment in the form of metabolic wastes and uneaten feed and faeces which pose a risk

to the environment if not properly managed (Price et al. 2015). Volkman et al. (2009)

estimated that approximately 30% of the nutrients added through fish feed in Tasmania are

removed at harvest, the rest being released as metabolic waste or uneaten feed. Localised

organic enrichment arises when fish feed and faeces settle on the seabed (Lumb 1989;

Holmer & Kristensen 1992; Hargrave et al. 1993; Karakassis et al. 2000). The natural

ability of sediments to assimilate this increased organic load is variable and depends on

several abiotic and biotic factors (Lumb 1989).

Changes in community structure may occur as the benthic community adapts to additional

and/or excessive nutrient loads. A gradient of impact has been demonstrated elsewhere and

where high levels of enrichment occur they are accompanied by opportunistic species and

bacterial mats (Beggiatoa) (Pearson & Roseberg 1978). The capitellid polychaete, Capitella

capita, is commonly found in organically enriched sediments and together with Beggiatoa are

recognised indicators of organic enrichment.

When the sediment capacity to assimilate such organic inputs is exceeded, the sediment can

become anoxic as the sediment biogeochemistry alters to a system dominated by anaerobic

forms of metabolism. Hydrogen sulphide and ammonia degassing are a feature of such

conditions and may adversely affect both the farm and the environment (Holmer &

Kristensen, 1992; Hargrave et al., 1993; Karakassis et al. 2000).

Approximately 80% of the total nutrient losses from fish farming are dissolved and in a form

that is readily available to macro- and micro-algae.

Environmental science

Understanding and monitoring the environmental impacts of salmon farming in Tasmania has

evolved in parallel with the development of the industry. Initial research focussed on the

impacts of farming on the soft sediment benthic habitats below and adjacent to the cages

(Crawford et al. 2002; Macleod et al. 2002; MacLeod et al. 2004b; Edgar et al. 2005).

Studies showed that nutrient enrichment from uneaten food and faecal material could impact

the benthos immediately below the cage (Macleod et al. 2004a and references therein), but

that there was a gradient of impact that diminished with distance from the cage (Edgar et al.

2005 and refs therein). Benthic impacts of salmon farming were minor at distances greater

than 35m from the lease boundary (Edgar et al. 2005) although local conditions greatly

influenced the level of impact at the level of individual farm leases (Macleod et al. 2004a).

6

Research on the broadscale impacts of nutrient enrichment in the water column and its effect

on primary production, predominantly phytoplankton, was the focus of work done by the

Aquaculture and Aquafin CRCs. This significant body of research (CSIRO 2000, Volkman

et al. 2009), showed that eutrophication would become a problem if the assimilation capacity

for nutrients of a salmon growing area was exceeded. This could lead to phytoplankton

blooms, which may include species that produce harmful algal blooms (HABs), or be

manifested as increased production of benthic microalgae, macroalgae or epiphytic algae.

The released nutrients may change ambient nitrogen/phosphorus (N/P) ratios and could alter

the ratio of key phytoplankton species (e.g. from diatoms to dinoflagellates). Effects of

increased nutrients may also be seen at higher trophic levels, by altering the abundance and

species composition of zooplankton, which in turn can affect fish communities.

More recent research has focussed on the potential impacts of salmon farming on reef

ecosystems through sediment deposition or nutrient enrichment. Anthropogenic

eutrophication has been shown to change the structure and diversity of marine benthic

communities (Pearson & Rosenberg 1978, Lotze & Schramm 2000, Kraufvelin et al. 2010)

with opportunistic fast-growing species frequently occurring in eutrophic coastal waters

(Cederwall & Elmgren 1990). These macroalgal blooms are generally explained by

increased nutrient loads which selectively favour filamentous and foliose macroalgae.

However, studies of the far-field effects of nutrient enrichment from salmon farming in

Tasmania are inconclusive. In a study of macroalgal composition in the Houn Estuary and

D’Entrecasteaux Channel, Oh (2009) showed that sites located 100m from salmon farms

were different from reference sites 5km away, but that sites 400m from farms were not

significantly different from the control sites.

Analogous to the results of other studies on macroalgal composition and nutrient enrichment

from other anthropogenic sources, Oh (2009) found the effect of fish farms was characterised

by increases in the cover of epiphytes and total opportunistic algae (which included

opportunistic green algae, filamentous algae and algal turf). In particular, opportunistic green

alga of the genera Chaetomorpha, Ulva and Cladophora (the main constituent of filamentous

green algae in this region) were collectively responsive to the proximity of fish farms. Oh

(2009) also found that there was no apparent decline of canopy algae close to fish farms, as

has been reported for other cases of eutrophication. The study suggested that while variations

in the detectable effects of fish farms could be anticipated at scales of hundreds of metres,

they rarely reached distances of several kilometres away from farming areas.

Crawford et al. (2006) undertook an analysis of a 10 year dataset from two small marine

protected areas (Ninepin Point at the mouth of the Huon estuary and Tinderbox near North

West Bay) for changes in abundance of the seven most abundant macroalgal species. This

study was aimed at assessing whether broadscale impacts of effluent from marine farming

activities could be detected at rocky reef communities, but found no apparent patterns of

change in macroalgal community composition over the 10 year time period.

Similarly Valentine et al. (2016) were unable to find any consistent patterns of broad scale

change in macroalgal community structure in sites adjacent to salmon farms and sites remote

7

from salmon farms. From this it would appear that although nutrient impacts have been

detected some distance from salmon farms the nutrient load has been insufficient to result in

significant changes to macroalgal communities on rocky reef habitats.

To further understand these effects a research project (FRDC 2015-024 Managing ecosystem

interactions across differing environments: building flexibility and risk assurance into

environmental management strategies) is underway in SE Tasmania to specifically determine

whether the current on-farm monitoring and local scale impact indicators are “fit for purpose”

in new farming regions and under contemporary farming practices (IMAS 2016).

Monitoring

Early research on the impact of nutrient sedimentation on the soft sediment environments

under salmon cages in SE Tasmania, primarily under the auspices of the Aquafin CRC, led to

the development of a guide to the assessment of sediment conditions at marine farms in

Tasmania (Macleod and Forbes 2004). This guide remains the basis of current DPIPWE

monitoring protocols of the nearfield benthic impacts from salmon farming and is recognised

as current best practice (Woods et al. 2004, Keeley et al. 2014).

Subsequent research led to the development of the Broadscale Monitoring Program (BEMP)

in 2009 to assess water and sediment quality as a regulatory compliance requirement in

accordance with salmonid marine farming licence conditions. The BEMP was initiated

following an extended period of scientific research funded through the Fisheries Research

and Development Corporation (FRDC) and the Finfish Aquaculture Cooperative Research

Centre (Aquafin CRC) between 1996 and 2009. It was based primarily on recommendations

of research undertaken by Thompson et al. (2008) and Volkman et al. (2009), which looked

at the effects of salmonid aquaculture on the environment.

The key focus of the BEMP was on water-column and benthic effects on soft sediments

within the system, the primary concern for this program being the potential for

eutrophication. This need to understand how the broader ecosystem accommodates the

additional nutrient load resulting from aquaculture inputs has seen broadscale environmental

monitoring introduced as a system-wide monitoring requirement within the regulatory

adaptive management framework for the Huon Estuary and D’Entrecasteaux Channel and the

Macquarie Harbour Development Plan areas (IMAS 2016).

The BEMP provides an important and highly reliable body of information on the conditions

associated with salmon farming that has been independently authenticated and can therefore

be used by regulators, industry and other stakeholders to assess ecological condition and

support adaptive management strategies (IMAS 2016).

Okehampton Bay

Protocols underpinning the monitoring and management of salmon farming in Tasmania are

based on a significant body of research conducted over the past 15 years by IMAS, CSIRO

and others, much of which is found in the peer reviewed literature. This provides a sound

understanding of the impacts of salmon farming on the environment that is able to be adapted

to suite local conditions anywhere in the state.

8

While the impacts of salmon farming may be considered to be site specific in terms of the

physical and environmental characteristics of a particular site, there are fundamentals that

may be adapted and applied to any site. This is particularly the case where the general site

characteristics such as those at Okehampton Bay are similar to those found in SE Tasmania

where much of the research has been concentrated.


The adaptive management protocols developed through this research are sufficiently flexible

that they could be applied to any site around Tasmania.

The Panel noted that the monitoring and management of impacts of salmon farming in

Tasmania is considered to be world best practice.

The Panel formed the view that the research underpinning the understanding, monitoring and

adaptive management of the impacts of salmon farming would be applicable to Okehampton

Bay and as a result is of the opinion that the current environmental science supports the

proposed environmental management and monitoring of salmon farming in Okehampton

Bay.

9

2. The adequacy of the environmental baseline data and surveys to allow

the Director, Environment Protection Authority to establish a

contemporary environmental management regime for the proposed marine

farming activity

Baseline surveys

Baseline environmental data for proposed Great Oyster Bay marine farm zones were

collected by the Tasmanian Department of Primary Industries and Fisheries (Mitchell et al.

1996). Data collected included depth, acoustic characterisation of substrate type, and

standard grab sampling and video sampling to ground-truth sediment characteristics and to

describe biota. Okehampton Bay is described as being uniform sand substrate with numerous

screwshells (Maoricolpus roseus). Water depth ranged between 22-28m and a reef area was

noted in the northern part of the bay.

In 2000 a subsequent more detailed baseline survey of Marine Farming Lease #236 at

Okehampton Bay was conducted by Aquenal for Spring Bay Salmon (Aquenal 2000). This

survey described the benthos to consist of light grey-brown sand speckled with shell-grit with

a high level of seaweed cover. The seaweed consisted of red, brown and occasional green

algae and was consistently greater than 30%, patchy and reaching 100% in places. A high

diversity of fish and larger invertebrates were observed, from yellow and red sponges to

numbfish, cowfish and seastars. Sediment cores revealed a sandy sediment of primarily

marine origin. Dark streaks in the sediments implied a low oxygen regime existed or had

existed in the sediments at some time in the past. Redox potential results indicated a healthy

sedimentary environment at all sample sites and oxygenated sediment down to or below a

depth of 4cm.

The Aquenal study found a current of low speed relative to other similar study sites around

south-eastern Tasmania. Particle size analysis revealed fine sandy sediments containing

variable percentages of coarse sand and shell grit and fine silt and clay particles. This

suggested a sedimentary environment of moderate water level movement, with intermittent

high and low energy periods. They speculate that this flow regime may result in poor nutrient

dispersal rates and the deposition of sediment in the vicinity of the farm. They note however,

that the area is subject to large swells and storms that may assist in dispersal (of nutrients and

sediments). During the sampling period currents rarely fell below 1.1cm/sec implying a

consistent supply of fresh seawater. The flow direction indicated that sedimentation would be

greatest in the north-east.

Analysis of macrobenthic samples indicated a highly diverse and abundant fauna with a total

of 182 species and 3,463 specimens collected in 54 grab samples. This fauna appeared to be

typical of that present at 20-40m depth on the east coast of Tasmania in areas of well sorted

sand sediment and moderate water movement. Common species included polychaetes,

ostracods and amphipods, while the introduced screwshell Maoricolpus roseus was

overwhelmingly predominant.

10

Towed video transect data collected in October 2016 (Marine Solutions 2016) characterises

three main habitat types in Okehampton Bay: soft sediments, rocky reef and seagrass beds.

Variations in these habitat types were recorded throughout the bay with reef present on the

western and eastern sides of the bay. From the beaches the habitat goes from sand, to seagrass

and then back to sand towards the deeper middle parts of the bay. A visual survey that

extended 4km north and south of Okehampton Bay did not detect the presence of Macrocystis

pyrifera.

Other information

Several other studies that contain information on environmental conditions and ecological

risk factors that would potentially have some relevance or might further inform our

understanding of the habitats and ecology of Okehampton Bay and the potential risks

associated with/ to aquaculture development in this region are outlined by IMAS (2016).

They include:

- Long term studies of the reef ecology on the east coast of Tasmania (Barrett et al.

2007, Barrett et al. 2009), which provide a benchmark against which to detect system-

wide changes in reef biota. This work includes a reef system in Okehampton Bay that

has been assessed annually, since 1992.

- Additional data describing the algal community at sites in Okehampton Bay between

1999 and 2000. This study described the baseline algal communities in the area (at

Lords Bluff towards the northern end of Okehampton Bay, Stapleton Point (~10km

SE) and Magistrates Point, Maria Island), and looked in particular at how the

introduced kelp Undaria pinnatifida responded to disturbance (Valentine and

Johnson, 2003) and interacted with native kelp species (Valentine and Johnson, 2004).

- Several studies that document changes in water temperatures on the east coast of

Tasmania that may have important consequences for ecosystems, marine and coastal

processes (Ling et al., 2009; Pitt et al., 2010; Johnson et al., 2011; Last et al., 2011;

Wernberg et al., 2011; Frusher et al., 2014; Hobday and Pecl, 2014, Creighton et al.,

2015).

Relevant site characteristics

Depth

Lease #236 has a depth that ranges from approximately 21m at the northern end of the lease

to approximately 28m at the southern end (Figure 1).

11

Figure 1. Bathymetric map of the lease area (Aquenal pers. comm. Reproduce d with

permission).

A comparison between Okehampton and other existing farm sites in SE Tasmania is provided

in Table 1. This shows that Lease #236 compares favourably with many of the deeper leases

in the D’Entrecasteaux Channel, and that several others have a shallower mean depth.

12

Table 1 – Size, distance from coast, distance from reef and depth of marine farm leases in the

D’Entrecasteaux Channel (* denotes recent amendments or proposed amendments to

MFDPs)(after Buxton 2015)

LEASE SIZE

(hectares)

FROM

COASTLINE

(meters)

FROM

REEF

(meters)

MIN

DEPTH

(metres}

MAX

DEPTH

{metres}

AVERAGE

DEPTH

(metres)

Electrona

MF76 8

combined

Touches Over reef 10.0 17.0 14.5

Gunpowder

Jetty MF76 150 100

16.1 21.8 18.9

Tinderbox

MF90 19 185 210

19.0 29.0 23.9

Sheppards

Point MF94 20 50 35

18.0 30.0 22.3

Simmonds

Point MF154 7 240 220

16.0 18.0 17.1

Roberts Point

MF142 30 58 48

18.0 23.0 21.1

Sykes Cove

MF73 3 14 Over reef

No data

Apollo Bay

MF74 10 53 13

No data

Soldiers

Point MF110 15 790 120

21.0 24.0 22.6

Simpsons

Point MF115 9 10 Over reef No data

Simpsons

Point MF182 15 234 155 No data

Satellite

Island MF34 30 Touches Over reef

8.0 13.0 12.1

*Zuidpool

Rock MF141 154 2600 1100 33.5 43.5 39.5

Great

Taylors Bay

MF185

75 + 75 1320 1280 26.3 40.0 31.7

*Butlers

Point MF109 28 470 450

16.0 23.0 21.1

*Lippies

Point MF78 -

Existing

38 1200 430 42.0 47.0 46.0

*Lippies

Point MF78 -

Proposed

77 1460 410 32.1 48.8 45.6

*Browns

Point MF262 38 1130 410 No data

13

Current

Current flow data at 6, 9 and 24m depth collected near the centre of the lease between

January and April 2000 (Aquenal 2000), recorded mean currents speed of 2.63+1.11cm/sec,

3.17+1.63cm/sec and 3.10+1.73cm/sec respectively. Maximum current speeds were

12.4cm/sec, 11.7cm/sec and 15.0cm/sec respectively. This study characterised Okehampton

Bay as having currents of relatively low speed compared to other sites around Tasmania

which Aquenal suggested may result in poor dispersal of sediments and deposition close to

the farm.

However, more recent data collected using an Accoustic Doppler Current Profiler (ADCP)

(Tassal 2016) show current speeds that are considerably higher, 30cm/sec in shallow water

and slightly less than 5cm/sec in mid and bottom water depths (Figure 2). These data

compare favourably with Tassal farm sites at Butlers (Great Taylors Bay) and Creeses

(Wedge Bay).

Figure 2. Average current data measured at surface, mid -water and bottom from two current

farmed sites (Butlers and Creeses) and Okehampton Bay (Tassal 2016)

Sediment type and particle size provide further insights into the current regimes on the lease.

Aquenal (2000) describe the sediment as being light grey brown sand of marine origin

speckled with shellgrit. The mixed nature indicated variable water movement at the seabed.

Dark colours and black streaking in sediment cores across the lease implied that a low

oxygen regime existed or had existed in the sediments at some time in the past. Particle size

analysis show the area to be characterised by fine sandy sediments containing variable

percentages of coarse sand, shell grit, fine silt and clay particles. This indicates a sedimentary

environment of moderate level of water movement at the seabed with intermittent high and

low energy periods.

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

Surface Mid-water Bottom

Ave

rage

Vel

oci

ty (

cm/s

ec)

Okehampton Creeses Butlers

14

Temperature

No temperature data was recorded in the initial baseline survey conducted (Mitchell et al.

1997) but Aquenal (2000) recorded temperatures ranging between 15.5-18.3oC over the

period 20 January to 4 April 2000.

More recent temperature data has been recorded between August 2014 and April 2016 at five

sites in the Maria Island region (Figure 3) including Okehampton Bay (site MP2).

Temperatures were recorded at the surface, 5m and 19.4m depth. In Okehampton Bay

(Figure 4) the minimum temperature recorded was 10.3oC (bottom temperature in August

2016) while the maximum was 19.59oC (surface temperature in January 2015). Temperature

at depth was on average 0.4oC lower than the surface.

Figure 3. East Coast Environmental Monitoring Locations (MP1 -5) in the Maria Island region.

Sites marked as Okehampton Bay, Point Home, Magistrates Point (north) and Painted Cliffs

(south) are the sites studied as part of the FRDC project 2014-042: Understanding broadscale

impacts of salmonid farming on rocky reef communities .

Figure 4. Monthly water column temperatures (surface, 5m and bottom) recorded between

August 2014 and August 2016 at site MP2, Okehampton Bay. (Aquenal pers. comm.

Reproduced with permission).

15

Daily water column temperatures recorded between December 2015 and May 2016 are

summarised in Figure 5. Corresponding water temperature ranges are shown in Table 2 and

show that the water temperatures are fairly stable with less than a 2 degree variation from day

to day. During the marine heatwave experience in 2016, over a 6 day period from 8-4

February the surface temperatures were above 20oC. At depth, however, temperatures were

2oC lower.

Figure 5. Daily water column temperatu res recorded at Okehampton Bay (Aquenal pers.

comm.)

Table 2. Mean, Maximum and Minimum temperatures recorded at Okehampton Bay lease

#236 between December 2015 and May 2016

Depth (m) Temperature (oC)

Mean Max. Min.

3 17.7 20.5 13.8

10 17.5 20.2 13.8

20 17.2 19.4 13.8

25 16.9 19.2 13.7

A comparison of surface temperature data collected at three current farm sites (Creeses, Great

Taylors Bay and Roberts) and Okehampton Bay (Figure 6) showed a similar pattern at all of

the sites (Tassal 2016). During the marine heatwave experienced on the east coast of

Tasmania in 2016, temperatures recorded at Okehampton Bay were slightly lower than the

other three sites.

10

12

14

16

18

20

22

1/12/2015 1/01/2016 1/02/2016 1/03/2016 1/04/2016 1/05/2016

°C

Temperature

3 m 10 m 20 m 25 m

16

Figure 6. A comparison of sea surface temperatures recorded between August 2014 and July

2016 at farmed sites (Creeses, Great Taylors Bay and Roberts) and Okehampton Bay

Proximity to reef

The baseline survey conducted by Mitchell et al. (1997) mapped an area of reef to the north

of the lease which was in fairly close proximity to the lease (approximately 100m). Reefal

habitat in Okehampton Bay is shown in Figure 7. This shows areas of low profile reef to the

west at Flensers Point and to the east around Lords Bluff. There are areas of patchy seagrass

to the north of the reef in shallow water. Low profile reef is characterised as hard bedrock

bottom type when there is little change in relief and which overlaps with patchy reef and hard

sand substrate categories (SeaMap Tasmania). The long term MPA monitoring reference site

‘Okehampton’ is 650m from the lease boundary and is part of the IMAS MPA monitoring

program which has been surveyed each year since 1992 (Valentine 2016).

17

Figure 7. Benthic Habitat in Okehampton Bay (Lucieer pers. comm.) (A) denotes the position

of the long-term MPA monitoring site called ‘Okehampton’ and the position of lease 236 is

illustrated by the blue polygon.

Water quality parameters

Tassal instigated a monthly water quality monitoring program in August 2014 which

replicates the Broadscale Environmental Monitoring Program (BEMP) undertaken in the

Huon and D’Entrecasteaux regions (Aquenal pers. comm.). This includes measurement of

phytoplankton concentration (Chlorophyll a) and physico-chemical parameters (salinity,

temperature, DO) at the surface, 5m depth and 1m above the seabed at 25m (Figure 8a).

Total (N and P) and dissolved nutrients (NH4, NO3, PO4, SiO4) are measured at the surface

and seabed (Figure 8b).

These measurements provide sound baseline measurements against which the impact of

farming can be assessed.

18

Figure 8a. Water quality parameters (salinity, temperature, DO) and phytoplankton

concentration (Chlorophyll a) measured at Okehampton Bay. (Aquenal pers. comm.


19

Figure 8b. Water quality parameters measured at Okehampton Bay (Aquenal pers. comm.


20


The Panel formed the view that the initial Baseline Data for Proposed Marine Farm Zones in

Great Oyster Bay (DPIF 1998) was fit for purpose and that the subsequent Baseline

Environmental Assessment of Marine Farming Lease #236 at Okehampton Bay (Aquenal

2000) was more detailed than the zone assessments undertaken by IMAS under contract to

DPIPWE to support new or amending existing marine farming development plans (MFPDs).

The latter zone assessments are undertaken prior to any new development (or zone extension)

being approved, and provide a broad characterisation of the seabed in the area of focus; these

include photographic, acoustic, biological, and sediment sampling.

However, the baseline surveys of Okehampton Bay, while sound in terms of method and

adequate for their purpose, are nevertheless more than 16years old. As such they may not be

an up-to-date representation of “pre-farming” conditions. East Coast waters have been

gradually warming for the last 60 years due to climate change and the East Australian Current

extending further south (Ridgway 2007). It is predicted that the East Coast waters will

continue to warm (Hobday and Pecl 2014, Popova et al. 2016). IMAS (2016) note that whilst

is it unlikely that the specific topography of the development area would have changed

markedly over this time, more contemporary data with respect to the interactions with

threatened and endangered species and an update of habitat and hydrodynamic information

using the latest techniques is advisable. This will ensure that a true baseline is established

against which to measure any changes going forward. Clearly the original baseline surveys

in 1998 and 2000 would then serve as useful historical benchmark against which to consider

any longer term temporal changes.

The Panel is of the opinion that whilst the existing environmental data may well be adequate

to allow the establishment of a contemporary environmental management regime, it agrees

with the IMAS assessment and recommends that a further baseline assessment should be

carried out prior to the commencement of farming and prior to the establishment of the

management regime. This way no questions will subsequently arise as to the adequacy of the

data being used to assess the impacts of farming on the environment.




21

3. The adequacy of the Great Oyster Bay and Mercury Passage Marine Farming

Development Plan 1998 to allow for the implementation of a contemporary

environmental management regime for proposed salmonid marine farming at

Okehampton Bay.

A contemporary environmental management regime requires the statutory ability to ensure

environmental impacts are minimized and sustainable. In this instance it requires the ability

to assess the environmental status of the locality prior to commencement of commercial

activities (baseline studies), the monitoring of environmental impacts both in the vicinity of

the enterprise and broad scale as it develops and, the ability to impose actions to limit, reduce

or minimize any environmental impacts by imposing input restrictions.

The governance system applying to salmon farming and environmental management is

achieved through the provisions contained within the Living Marine Resources Management

Act 1995, the Marine Farming Planning Act 1995, the management controls contained within

the relevant Marine Farming Development Plans, the conditions on leases and licence

conditions.

The system applying to salmon farming in Okehampton Bay should be consistent with and

uniform with the management and regulation requirements implemented elsewhere in the

State where in general the regulation of the industry has been assessed as world’s best

practice (Woods et al. 2004, Keeley et al. 2014). This does not mean that endeavours to

improve environmental management should not be exploited when issues or opportunities

arise. The development and adoption of adaptive management in recent years across the

industry is testament to this approach.

In this regard the management controls contained within the Great Oyster Bay and Mercury

Passage Marine Farming Development Plan October 1998 (the Plan) are not consistent with

all other Development Plans in relation to finfish farming. There is no head of power for the

determination of nitrogen inputs from salmon farming operations and the apportionment of

total dissolved nitrogen inputs amongst leaseholders as is now the case with all other Marine

Farming Development Plans.

The Panel recognised these shortcomings in the Plan and this issue was addressed by the

Panel following a request from the Minister in April 2016. The Panel has approved a draft

amendment to the management controls that will, when implemented, achieve uniformity and

consistency with all other Plans with respect to finfish farming.


Subject to the nitrogen input issue being addressed the Panel is of the opinion that the Plan

and its supporting management framework will set out best practice and allow for a

contemporary environmental management regime for salmonid farming in Okehampton Bay.

22

For the Okehampton licence, the IMAS submission refers to specific licence conditions being

imposed to require more recent baseline and additional broadscale water quality and reef

interaction monitoring to address the key environmental management concerns. The Panel is

of the view that this can be achieved under the existing management controls.

23

Response to issues raised in submissions:

This section lists the major issues raised through submissions and provides a brief

response/commentary on each.

1a. Baseline data out of date

Several submissions expressed the concern that the baseline environmental data was not

current and may therefore not be suitable for the purpose of monitoring the impact of salmon

farming.

1b. Baseline data not available

Several submissions expressed the concern that baseline data was either not available or not

available at the time of the announcement of the inquiry.

1c. Baseline surveys inadequate

Several submissions contend that the baseline surveys were inadequate:

- Did not include temperature data.

- Lack of adequate control sites eg rocky reef.

- Historical datasets important but should not be solely relied upon in determining

whether OB is suitable for finfish farming.

These issues are addressed under ToR 2.




2. Temperature too warm to support salmon farming

Several submissions argued that the temperature in Okehampton Bay was too warm to

support salmon farming:

- Okehampton, with much higher water temperature, much higher total stocking

densities proposed for one site and very low speed water flows would be an

environmental disaster waiting to happen.

- Baseline data limited temporally. Temperature information on the Tassal website all

surface measurements with no information at depth. As far as is possible to ascertain

from the published graphs [on Tassal website], the maximum monthly surface

temperature reached at the site during this period [August 2014-August 2016] was in

the order of 19degC in Jan 2016. The previous year, the average maximum

temperature reached appeared to be 18degC. The preferred temperature range for

Atlantic Salmon farming in Australia is between 16degC and 18degC at a depth of

5m. It is clear from the Baseline data and more recent environmental monitoring that

the Okehampton Bay site regularly experiences water temperatures at or above the

upper limit of the ideal temperature range for the growing of salmon…..responsibility

24

of Government to ensure that the community and the environment is protected from

unsustainable development.

- Tassal had made available on their website what they claim to be sufficient

information to inform public comment…..it includes graphs of monthly temperatures

and dissolved oxygen, for example, which is meaningless when daily maximum

temperature and DO [dissolved oxygen] are the key considerations for fish health and

site sustainability.

The Panel noted the concerns, however, disagreed that temperatures in Okehampton Bay

were ‘much higher’ than other leases occupied by the salmon industry.

The Panel rejected the argument that the temperatures at Okehampton Bay were too high for

salmon farming noting:

- That recent temperature profiles between August 2014 and August 2016 (Figure 5)

showed that Okehampton Bay was similar to other Tassal sites in SE Tasmania

including Creeses, Great Taylors Bay and Roberts.

- Optimum temperatures for Tasmanian salmon farming were between 16-18degC.

- Recent daily temperature records did not support the argument that maximum daily

temperatures were unsuitable for salmon farming.

- Adaptive farm management practices (smolt in late, harvest before warm period and

selective breeding) could mitigate issues relating to temperature.

The Panel noted concerns relating to the high summer temperatures which at times may

exceed the preferred temperature range of the species but saw these as business concerns for

the farmer and not issues of environmental concern.

3. Water current too low to support salmon farming

Several submissions drew attention to low water flows at Okehampton Bay and the related

capacity of the area to assimilate waste.

- Reference to a news article (6 Sept 2016 936 ABC Hobart) which quoted Rowan

Armitage as saying “We’re going to get faecal mounds underneath the pens” and ‘A

storm comes through, that [faecal material] is all going to get stirred back up into the

water column, which is going to strip oxygen out of the water column and going to

move as an oxygen deprived mass of water [and be fatal for other fish in the

environment].

- The environmental science presented does not give confidence that the water flow

rates are high enough to allow effective dispersal of fish farm sediment.

The Panel noted that the capacity of the environment to assimilate fish farm wastes through

sediment microbial processes was an important consideration for open cage aquaculture.

This process was assisted by water movement and the oxygenation of the sediments.

25

The Panel noted that current farm practices (eg feed formulation, feed rates, stocking density

and fallowing) were used to manage waste build up, and formed the view that current

monitoring and adaptive farm management practices would be sufficient to deal with the

problem if it arose.

4. Depth too shallow to support marine farming

Several submissions drew attention to the depth of the lease, arguing that it was too shallow

to support marine farming.

The Panel rejected the argument that Okehampton Bay was too shallow for finfish farming

noting:

- That Lease #236 has a depth that ranges from approximately 21m at the northern end

of the lease to approximately 28m at the southern end (see Figure 1). This compared

favourably with many leases in the D’Entrecasteaux Channel (see Table 1) several of

which had a shallower mean depth.

- That the depth of salmon cages used by Tassal was 15m which would leave between 6

and 13m clearance between the net and the ocean bottom.

5. Stocking density

One submission noted that lease #236 would not be able to support the maximum stocking

density (25kg/m3) due to the low water flows and temperatures in the area.

The Panel formed the view that the baseline data and other environmental information did not

support this argument.

The Panel noted that environmental issues relating to stocking density could be managed

through licence conditions.

6. Modelling of impacts of marine farm wastes

One submission drew attention to the lack of information on the potential impact of waste on

the marine environment.

- We assume that Tassal has undertaken predictive modelling relating to the deposition

and dilution of marine farming waste….

- Without access to information about the proposed stocking density, feeding regimes

and cage sizes and depths, it is not possible for other stakeholders to make detailed

submissions about whether Tassal’s assertion [in relation to assimilation capacity] is

supported by the science.

The Panel noted the considerable body of scientific literature on the impacts of salmon

farming on the environment (see ToR 1).

26

The Panel noted that the software package DEPOMOD was being used to model the benthic

footprint of faeces deposition and feed wastage (Aquenal unpublished report). This footprint

modelling was based on local current patterns and planned production. The use of

DEPOMOD will assist with the understanding of:

- The nature of the emissions footprint

- Ways in which feed practices can be altered to minimise the emissions footprint (eg

reduce feeding during particular environmental conditions to minimise footprint)

An example of a DEPOMOD output is shown in Figure 8.

Figure 8 example of a DEPOMOD output for the Okehampton Bay lease.

7. Irreversible damage

Several submissions expressed a concern that environmental damage would be irreversible.

Concern was also expressed as to who would be responsible for the clean-up of an

environmental disaster.

- ….who will be responsible for rectifying the situation in an acceptable timeframe for

all concerned.

27

- …will the damage be permanent.

- …damage is done, the channel will take a long time to recover if ever!.

The Panel rejected the argument that the impact of salmon farm waste was irreversible noting

the work done in Tasmania that showed conclusively that the effects of salmon farming on

the environment were localised and that sediments recovered quickly when fallowed

(Macleod et al. 2002, 2004a,b, 2008).

The Panel noted that managing the impacts on the environment was a responsibility of the

farmer under licence conditions.

8. Suitability of the site for finfish farming questioned

Several submissions questioned the suitability of Okehampton Bay as a site for finfish

farming, noting that since the initial evaluation environmental conditions had changed.

- Climate change not included in the Plan

- …whether the proposed site is suitable for these activities in the first place

- There is no environmental science that could possibly support this proposal

The Panel rejected assertions that Lease #236 at Okehampton Bay was unsuitable for salmon

farming noting that baseline surveys and more recent environmental information on

conditions in Okehampton Bay showed that it was similar to other areas in SE Tasmania

where salmon farming existed.

9. Bioaccumulation

One submission drew attention to potential synergistic effects of farming both salmonids and

shellfish on the marine environment or the effect of one specie (sic) to another.

- In particular bioaccumulation of bacteria (1) or heavy metals (2) from salmon species

in bivalves.

The Panel noted that the references cited did not support the concern. For example Skar and

Mortensen state that their results indicate that the ISAV [fish pathogenic infectious salmon

anaemia virus] is rapidly inactivated in mussels and that mussels are not a likely reservoir

host or vector for ISAV.

1. Skar and Mortensen (2007) Diseases of Aquatic Organisms 74: 1-6.

2. Stirling and Okumus (1995) Aquaculture 134: 193-210.

28

10. Risk of salmon farming to reef productivity

The Tasmanian Abalone Council expressed a concern that the expansion of the salmon

industry was detrimental to the productivity of the abalone fishery.

- It is the view of TAC that further inshore expansion of the Tasmanian salmonid

industry (including the Tassal Okehampton Bay proposal) should be suspended until

such time as this critically important FRDC project [FRDC 2015-024] is completed

[in 2018].

- Block 24 (Figure 9a) has produced an average catch of 53.4 tonnes per year from

2006 to 2014.

Abalone catch rates in block 24 are shown in Figure 9 (Craig Mundy IMAS pers. comm.).

These data show that most of the catch in block 24 comes from sub-blocks D and E. Catches

from sub-block 24C (which includes Okehampton Bay) are the lowest of the five sub blocks,

and since 2002 less than 2t have been taken from the area. Catch rates have also been well

below target (the dashed blue line) over this period.

The Panel noted the review conducted by Buxton (2016) which concluded the risk to existing

abalone fisheries was low.

The Panel formed the view that delaying a decision to proceed in Okehampton Bay until

research had been completed was not necessary as the research could be incorporated into

adaptive management protocols as information became available.

The Panel agreed with the suggestion to expand FRDC 2015-024 if possible, to include an

evaluation of reefs in this area.

Figure 9a. Abalone fishing blocks adjacent to Maria Island and Okehampton Bay

29

Figure 9b. Total catch in each quarter and catch rates (CPUE) for sub block 24A. The dashed

blue line i llustrates the target catch rate for the area , the red line is the bias corrected

geometric mean CPUE and the black line with error bars is the standardised mean CPUE .

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Figure 9d. Total catch and catch rates (CPUE) for sub block 24C.

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Figure 9e. Total catch and catch rates (CPUE) for sub block 24D.

Figure 9f. Total catch and catch rates (CPUE) for sub block 24E.

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11. Climate Change

Several submissions draw attention to the fact that when the Plan was written, climate effects

were not considered and that these effects will have consequences for the salmon industry.

- …the state’s largest aquaculture company had to withdraw two major tenders because

of climate change.

- …climate change predictions for further increases in temperature.

- Proper assessment of the effects of climate change on viability.

Several studies document water temperatures on the east coast of Tasmania which may have

important consequences for ecosystems, marine and coastal processes and seafood

production. Water temperatures have warmed over the past 60yrs and are predicted to

continue rising at rates that are amongst the fastest in the world (IMAS 2016 and references

therein).

In early January 2016 temperatures reached 4.5oC above average as a result of an

unprecedented marine heatwave associated with the El Nino weather pattern.

Climate change clearly presents a number of potential concerns and management

implications for seafood industries in this region; both with respect to the effects of increased

temperature on culture species directly and the challenges presented as a result of secondary

effects - such as changes in local productivity and the spread of potentially harmful species.

Battaglene et al. (2008) documented potential effects on salmonid health and on growth and

nutrition before discussing solutions including alternative species. Without any change in

practices, increased seawater temperature is likely to decrease production through increases

in thermal stress and disease events and decreases in feed intake and growth. The industry is

currently addressing these issues in various ways including changing farm management

practices, site location, and selective breeding.

The Panel noted the science that pointed to a warming of the waters on the east coast but

noted that this was not specific to the Plan as other areas where farming currently takes place

are subject to similar conditions.

The Panel formed the view that countering the impacts of global warming would be a whole

of industry problem. The Panel further noted that the problem was being addressed by

industry farm management practices, site location and selective breeding.

The Panel agreed with the IMAS (2016) view that particular circumstances relevant to the

locality needed to be clarified and incorporated into the environmental management

protocols.

12. Harmful Algal Blooms (HABs)

Several submissions drew attention to concerns relating to the prevalence of toxic algal

blooms on the east coast of Tasmania.

33

- There is no data on nutrient levels in the water column…. There should be no new

sources of pollution dumping nutrients … into Tasmania’s marine environment

- The site is currently experiencing HABs, creating pressure for our shellfish industries

and risks to human health. Introducing a significant additional source of nitrogen will

increase the risk of HABs in the bay

- …nitrogen released from faeces entering the water column, increasing the risk of

toxic algal blooms

- …commercial and recreational fishing closures ….in the last few years as a result of

toxic algal blooms caused by rising algal temperatures

IMAS (2016) notes that the occurrence of harmful algal blooms has increased markedly in

the waters off the East coast of Tasmania since the Great Oyster Bay and Mercury Passage

Marine Farming Development Plan was first developed in October 1998. In October 2012

widespread blooms of the neurotoxic dinoflagellate Alexandrium tamarense affected the

entire east coast of Tasmania, resulting in several instances where seafood products were

identified to contain paralytic shellfish toxins (PST) (Campbell et al., 2013). These blooms

have returned each winter-spring (Jun.-Nov.) from 2013 to 2016 (Bolch et al., 2014). In 2015

blooms resulted in extensive shellfish closures, mass shellfish deaths in some enclosed

estuaries, serious disruption to shellfish hatchery production, and human poisonings from

recreationally collected shellfish. The winter bloom this year (2016) was the most severe

outbreak yet experienced, and the most seriously affected areas include the coastline from

Moulting Bay (St Helens) to Great Oyster Bay to Spring Bay and Mercury passage. Marine

farm and wild harvest closures have included mussels, oysters, scallops, lobsters, abalone,

and crabs for periods as long as six months.

In the water column, soluble nutrients can alter species composition and density of

phytoplankton, increasing the risk of toxic algal blooms, however, to date there have been

few studies that show a link between nutrient discharge from fish farms and the occurrence of

HABs (Price et al. 2015 and references therein). They caution, however, against siting farms

in areas with historically occurring HABs.

Whilst there may be no link between finfish production and the prevalence of toxic algal

blooms, there is the demonstrated potential for these blooms to have adverse effects on

farmed fish. Alexandrium tamarense blooms have been known to kill caged fish in other

regions (e.g. Chile, North East America) (IMAS 2016).

Price et al. (2015) note significant advancements in feed formulation and management

protocols that are largely credited for reducing nitrogen and phosphorus loading and other

impacts from marine cage culture.

The Panel noted the presence of regular blooms of A.tamarense on the East coast of

Tasmania would potentially represent a serious risk to salmonid culture and agreed with the

IMAS (2016) submission that it may be prudent to i) undertake research to better understand

the potential for adverse interactions with salmon, and ii) to include monitoring and

management actions relevant to this species in the environmental management protocols.

34

13. Risk to whale migration

One submission expressed a concern that the proposed salmon farm at Okehampton Bay

could pose a risk to whale migrations.

IMAS (2016) noted that over 40 resident and migratory species of marine mammals visit the

East coast of Tasmania seasonally. Information regarding the movement patterns of these

species, such as southern right whales (Eubalena australis) and Humpback whales

(Megaptera novaengliae) is very limited; although they are known to migrate north and

southwards along the East coast between April and November each year (Carroll et al. 2011).

Southern Right whales tend to come more inshore and are listed as “Endangered” under the

EPBC Act (1999) (SEWPaC 2012), consequently some further research may be warranted to

better understand the potential for interaction with aquaculture facilities.

The Panel noted this concern and agreed that further research was warranted to better

understand the interaction between migrating mammals and aquaculture facilities. The Panel

noted that Mercury Passage contained existing mussel aquaculture infrastructure and did not

believe that this matter was sufficient to delay the development of the site.

14. Risk to the Maria Island Marine Reserve

Several submissions suggested that salmon farming at Okehampton Bay would pose a risk to

the Maria Island Marine Reserve.

Research shows that while salmon farming may have significant near field impacts below the

cages, there is a gradient of impacts such that effects beyond 35m from the lease boundary

are minor (Edgar et al. 2005). While the impact on reefs is less well understood, the recent

review of the Broadscale Environmental Monitoring Program (BEMP) found no evidence of

any major broadscale impacts of salmon farming at present in the Huon / D’Entrecasteaux

Channel region (Ross & Macleod 2013).

Far field impacts are less well understood and is the focus of research that seeks to improve

the understanding of the potential interactions among salmon farming, macroalgae, and reefs,

and in particular the effect of increased nutrients on reef ecology and dynamics (Macleod

2015). Proliferation of intertidal “nuisance” algae in response to increased nutrients in the

Huon and D’Entrecasteaux region was assessed in 2003 and suggested no obvious causal

links to salmonid farming (Crawford et al. 2004). A reassessment of these sites 11 years after

this initial assessment has recently been funded (FRDC CC035 Reassessment of intertidal

macroalgal communities near to and distant from salmonid farms and an evaluation of using

drones to survey macroalgal distribution) given concerns that the abundance of opportunists

has increased in recent years as a result of the overall expansion of the salmonid aquaculture

industry. Crawford et al. (2006) undertook an analysis of changes in abundance of

macroalgae based on long term data sets (1992- 2002) at the Ninepin Point and Tinderbox

Marine Protected Areas (MPAs) to assess whether broadscale impacts of effluent from

marine farming activities could be detected. This report found no apparent patterns of

changes in macroalgal community composition over the 10 year time period.

35

Oh (2009) examined macroalgal community data at varying distances from 12 active

salmonid lease areas in the D’Entrecasteaux Channel and found that the macroalgal

community composition at sites 100m distant were significantly different from those at sites

5 km away in both exposed and sheltered locations. Sites at 400 m varied in their response to

farms, with some sites showing characteristics similar to 100 m sites. The change in

community composition observed by Oh (2009) was due to an increase in the cover of

epiphytic algae and the presence of opportunistic algae, with no apparent change in the

dominant canopy forming perennial algae.

The Panel noted that the Maria Island reserve was approximately 6-8km from the

Okehampton lease and formed the view that nutrients from the proposed salmon farming

operation were unlikely to affect the reserve.

15. Plan out of date

Several submissions address concerns in relation to the Great Oyster Bay and Mercury

Passage Marine Farming Development Plan 1998 (the Plan) including the following:

- That the Plan was reviewed in 2007 but no new science was included at the time of

the review.

- The information on which the decision to allow finfish farming at Okehampton Bay

was based is out of date and the suitability of the site is now disputed.

- That the Marine Farming Planning Act requires that a full review of the plan inclusive

of an EIA should be undertaken prior to any approval of farming activities at

Okehampton Bay.

- That the proposed monitoring and management provisions in the Plan may no longer

be appropriate, given the changes both in salmon farming practices and in the broader

ecosystem over the last 20 years.

- Okehampton predicated to be suitable for farming.

The Panel noted that these concerns did not specifically address the terms of reference.

The Panel disagreed with the view that because the Plan was due for review, Lease #236 was

unsuitable for marine finfish farming.

The Panel formed the view that the key site characteristics including depth, substrate type,

temperature profile and current speeds are all within the range of sites currently used by

industry.

16. Narrow Terms of Reference (ToR) and public consultation period prevent

genuine consultation and will not instil community confidence

Several submissions argued that the ToR were too restrictive:

36

- …submission process does not provide circumstances that will achieve the goal,

stated repeatedly, by the Minister of ‘community confidence’

- The ToR highly restrictive and not conducive to genuine engagement… …timeframe

way too brief

- …ToR too restrictive and indeed irrelevant as to improving community confidence in

expansion of the salmonid farming industry

- …process has the look and feel of a ‘fast-track’ or ‘token’ assessment, designed to

deliver a pre-determined outcome. A wider TOR, extended submission closure date

and better access to baseline data would dispel this perception

- …restricted scope and timing…

- There are no clear, specific TOR pertaining to impacts of fin-fish farming at the site

on other coastal users, including the tourism industry, the commercial fishing

industry, recreational fishing and boating communities and the local community on

the east coast

The Panel noted that this issue did not address the ToR.


environmental data were not freely available and noted that greater transparency and public

availability of data would improve community confidence in the sustainability and

management of salmon farming.

17. Impact on WHA

One submission drew attention to the absence of baseline data, predictive modelling or

associated environmental plans in regard to the impacts the Okehampton Bay proposal will

have on the cultural heritage values on the Darlington Convict Station WHA site on Maria

Island. This submission contends conservation and management of cultural heritage values

falls within the definition of ‘environment’ under Section 528 of the EPBC Act 1999. The

submission concludes that “…should Tassal’s proposal proceed in its present from it poses a

significant danger to Darlington’s World Heritage Values.”

The Panel noted that this submission did not specifically address the TOR.

18. Visual impacts


19. Compromises nature based tourism associated with Maria Island


37

20. Marine farm noise

One submission drew attention to marine noise.

- Scientific studies demonstrate the impact of marine noise on mammals. Plan doesn’t

specify limits therefore licence must.


21. Review Panel not independent

Several submission argued that the Review Panel was not independent as DPIPWE appointed 6

of its 8 members.


The Panel noted:

- Membership of the Panel is prescribed in section 8 of the Act and are appointed by the

Governor

- Panel members are appointed because of their particular skill set. No appointments

are subject to any controls, express or implied, from any source.

- Appointments are for a fixed term

- Panel members are precluded from acting if they have a conflict of interest; this is

addressed at the start of each meeting.

- Panel members have a wealth of experience in administration and/or corporate

activities, understand independence, and that includes looking at things objectively

- ToR involve questions of fact.

- Minister makes decision not the Panel

38

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