Shark Hazard Mitigation: An approach for Western Australia 4 July 2018 - Department of the Environment and Energy
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
Shark Hazard Mitigation: An approach for Western Australia 4 July 2018
INTRODUCTION
It is primarily the responsibility of the states and territories to manage public safety in their
waters and the risks to humans from sharks. This document provides advice to WA to improve
its management of shark hazards and support the safety of Australians in its waters.
As noted by Minister Frydenberg, the “primacy of public safety is non-negotiable”i and, though
interactions between humans and sharks are rare, shark attacks can be extremely traumatic
and pose a serious risk to human life. It is also important that shark hazard mitigation
strategies minimise harm to sharks, other marine species and the environment.
A key point of difference between WA and other key states has been identified—the
deployment of SMART drumlines—which could enhance public safety in WA, while being
sensitive to the environment.
SUMMARY OF CURRENT SHARK HAZARD MITIGATION APPROACHES
Over many decades a range of strategies have been in place throughout Australian waters to
reduce the risk of shark attacks.ii Strategies have included the use of aerial surveillance,
swimming enclosures, diver cages (used by the SA Government), and mesh nets and
traditional drumlines (deployed by the QLD Government).iii,iv
Recent shark attacks, particularly in NSW and WA waters, have prompted state governments
to build on their existing strategies by investing in new technology, tools and publicly
accessible information. These strategies have typically focussed on measures that improve
human safety in a way that is non-lethal to sharks and other marine life. These include, for
example: the use of drone technology and increased aerial surveillance measures, smart
phone apps that provide real-time warnings and information for beach-goers, and funding for
science and research into shark behaviour.v
In 2017, the WA Government announced its approach to shark hazard mitigation in its
waters.vi While the WA Government’s model has some similarities to the NSW Government’s
Shark Management Strategyvii, there is one key point of difference; the lack of use and
deployment of the emerging SMART (Shark Management Alert in Real Time) drumline
technology.
SMART drumlines
Unlike traditional drumlines, SMART drumlines are non-lethal and allow caught sharks to be
tagged and released alive, approximately 1km offshore. When SMART drumlines are
managed in a non-lethal manner (i.e. teams respond immediately to manage the caught
animal) they are unlikely to have a significant impact on matters of national environmental
significance and therefore the Department of the Environment and Energy has not required a
referral under the EPBC Act in NSW.
Preliminary results from the NSW trials indicate SMART drumlines have proven to be effective
in catching target shark species (Great White, Tiger and Bull sharks) and minimising
bycatchviii.
1
SMART drumlines are an
emerging technology designed
to be non-lethal. They have
been trialled by the NSW
Government since 2015.
SMART drumlines differ from
traditional drumlines as they
allow sharks and other marine
fauna that are caught to be
tagged, relocated and released.
They comprise of an anchor and
rope, two buoys, and a satellite-
linked communications unit
which is attached to a trace and
baited hook. When an animal is
hooked, the pressure triggers
the communications unit, which
alerts an expert team to the
presence of an animal. The
team is able to respond
immediately.
SHARK RISK IN WESTERN AUSTRALIA
Shark numbers and species
Over 100 species of shark live in WA waters, ranging from the 30cm long Pygmy Lantern
Shark to the 12 metre long Whale Shark. The vast majority of shark species are not dangerous
to humans and nearly all fatal attacks can be attributed to just three species: Great White
Sharks, Tiger Sharks and Bull Sharks.
These three species are known to live in WA waters, with Great White Sharks being
responsible for approximately 94 per cent of fatal shark attacks in WA since 1980.ix
On 8 February 2018, CSIRO published the first robust estimates of Australian Great White
Shark populations, using breakthrough genetic and statistical methods. This world-class
research was supported by the National Environmental Science Program.x
CSIRO’s research found that there is a significantly higher number of Great White Sharks in
the south-west of Australia in comparison to the east in Australia’s southern and western
waters. The current adult population in eastern Australia is around 750 Great White Sharks
(range: 470 to 1,030), with a survival rate—the chance of surviving from one year to the
nextxi—of 93 per cent. In contrast, the southern-western population is estimated to have
around 1,460 adult Great White Sharks (range: 760-2,250), with a survival rate above 90 per
cent year-to-year.
The prevalence of shark attacks
The table below indicates that, in comparison to other states and territories, WA has had the
highest number of shark attack fatalities over the last 10 and 25 year periods.
2
Shark Fatalities QLD NSW WA SA Vic Tas NT
Last 10 years 2 4 12 2 0 1 0
Last 25 years 6 6 17 9 0 1 0
Note: Data in this table is sourced from the Australian Shark Attack File (as supplied by Taronga Conservation Society Australia)
and relates to provoked and unprovoked attacks. Data is accurate as at 6 June 2018.
Furthermore, the experience of NSW and Queensland is particularly instructive with there only
being one fatality at a protected beach in more than 50 years.
Across Australia, the most common activities during which attacks are sustained are
swimming, diving (including all types of diving activities such as snorkelling, scuba diving and
hookah diving) and surfing. While attacks on swimmers and divers have generally remained at
stable levels, attacks on surfers have increased. The 12 fatalities sustained in WA over the
last 10 years occurred when the victims were undertaking the following activities: surfing (6),
scuba diving (3), snorkelling (2) and swimming (1).xii
Map 1 below provides a visual representation of where there have been shark interactions
over the last 25 years in southern WA. The map also highlights two regions where there has
been a concentration of shark attacks: the metropolitan and south-west regions.
Map 2 below provides an overview of indicative locations where SMART drumlines could be
deployed in the two regions. It shows where surf lifesaving clubs are located along the coast
and describes the number of shark interactions in the past 25 years.
Map 3 below zooms in on the two regions to provide, at a more detailed level, a view of the
key beaches, surf zones, towns and historical shark attacks over the last 25 years in the two
identified regions. It also includes an indicative number of SMART drumlines that could be
deployed at each location. This is summarised in the table below, which outlines the patrolled
beaches and towns in each region (including an indicative number of SMART drumlines—176
in total—that could be deployed at each location) that could be captured under this approach.
METROPOLITAN REGION # of drumlines SOUTH-WEST REGION # of drumlines
Quinns-Mindaria 8 Bunbury 13
Mullaloo to Sorrento 12 Dalyellup 8
Trigg Island to City of Perth
11 Peppermint Grove 12
(captures Scarborough, Floreat)
Swanbourne Nedlands to
Fremantle (captures North 13 Busselton 8
Cottesloe, Cottesloe)
Coogee 8 Eagle Bay to Yallingup 31
Warnbro 8 Gracetown 16
Secret Harbour to Port Bouvard 23 Prevelly 5
TOTAL 83 TOTAL 93
There are no special purpose surfing zones. There are 10 special purpose surfing zones.
Note: Final placement/number of SMART drumlines at each location is subject to local conditions.
The placement and number of SMART drumlines is indicative and based on known beaches,
surf zones or towns where there have been shark interactions over the last 25 years with an
average distance of 1.5 km between each SMART drumline. Marine sanctuary zones are also
3
avoided. The final placement of drumlines will be informed by close examination of local
conditions, including analysis of the ocean floor.
These regions expand upon the regions that were targeted under a previous WA trial drumline
program in 2014. The trial program was conducted at eight popular beach sites from January
to April 2014 and aimed to enhance public safety by capturing potentially dangerous sharks
which came into close proximity of popular beaches and surfing spots during summer.xiii The
trial program did not use SMART drumlines.
As discussed in further detail in the next section (Pathway forward for Western Australia:
SMART drumlines) there is an opportunity for WA to deploy SMART drumline technology in
these regions to improve on its existing shark hazard mitigation regime.
4
Map 1 5
Map 2 6
Map 3 7
PATHWAY FORWARD FOR WESTERN AUSTRALIA: SMART DRUMLINES
According to a 2014 review of the WA 2014 trial drumline programxiv, 50 sharks (three metres
or greater) were captured. All of these sharks were Tiger Sharks—a target species under the
trial program—which are identified as one of the three species accounting for almost all
fatalities from shark attack globally over the past 30 years. The review stated that:
“It is considered likely that capture of a significant number of large sharks close to
high use swimming and surfing areas reduced the risk of shark attacks. The trial
has been short, and shark attacks generally too infrequent, to have generated
substantial quantitative data to measure the reduction in risk. It is recommended
that the program be extended for another three years and then be reviewed
again.”xv
Although the review recommended that the trial program be extended, it was discontinued.
There are no longer any permanent drumlines deployed off the WA coast.
NSW SMART drumline program
The NSW SMART Drumline program has had success in capturing target shark species. On
13 February 2018xvi, the NSW Government announced the results of SMART drumline trials
on the mid north coast including Coffs Harbour to Sawtell and Forster-Tuncurry. From August
to December 2017, 64 sharks were caught, tagged and released at Forster-Tuncurry and an
additional 15 at Coffs Harbour. During the trial, target sharks caught on the SMART drumlines
were able to be tagged and tracked. This research is providing important insights into the
shark’s movements and behaviour. For example, once tagged, sharks generally stayed in
deeper offshore waters for up to four weeks.
The survivability of catches has been found to be higher on SMART Drumlines in comparison
to shark nets, with all but one of the animals caught on SMART drumlines being released alive
(97 per cent) versus a 47 per cent survival rate in shark nets (128 animals were found alive
while 147 did not survive).xvii
There were two human-shark interactions during NSW’s Government’s SMART drumline trial
in the trial zones. At the time of the Kiama Beach interaction, SMART Drumlines were not in
the water. At the time of the Lennox Point interaction, a SMART Drumline was in the water
approximately 700 metres down the beach from the surfer.
SMART drumlines in WA
The maps below provide a more detailed illustration of how the WA Government could deploy
SMART drumlines along the two regions by highlighting iconic beaches. This is overlayed with
the number of shark attacks over the last 25 years, population density and locations of surf
lifesaving clubs.
In addition, information is provided on the estimated costs associated with the deployment of
SMART drumlines in each location. Estimated costsxviii indicate the operation and maintenance
of a single SMART drumline could range from $24,380 to $33,680 for a six month period (plus
a $5,000 purchase cost). This suggests that a six month SMART drumline program—rolled out
across the Metropolitan and South-West regions—could cost around $5-7 million for 176
drumlines. The costs could be further reduced if the WA Government accepts the NSW
Government’s offer to loan them five SMART drumlinesxix. Additionally, the costs could be
8lower for subsequent years as the WA Government would own the SMART drumline
technology.
The area would cover approximately 260 km of coastline. Over 80 per cent of WA’s population
lives within 30 km of the coast in these two regions. The combined regions include 19 beach
areas patrolled by surf life-saving clubs, 10 special purpose surfing zones and a large variety
of unpatrolled beaches and surf-breaks.
It is important to note that SMART drumlines do not offer 100 per cent protection to all
beachgoers, particularly those swimming in remote areas (such as divers beyond 500 metres).
A SMART drumline program would need to operate as part of a multifaceted shark mitigation
program and should be complementary to existing efforts. All required state and
Commonwealth environmental approvals would need to be in place, including avoidance of
relevant marine sanctuary zones, before a SMART drumline program could commence.
The approach outlined in this document is conservative and based on the deployment of one
SMART drumline, on average, every 1.5 km. Through expert analysis of local conditions, the
total number of SMART drumlines could be reduced from 176.
This document does not seek to provide a direct comparison between the costs of the NSW
SMART drumline program with the WA 2014 trial drumline program. While the 2013-14 WA
program was $1.28 million for 14 weeks over the two regions and would appear to be less
costly than the NSW model, a direct comparison is misleading as the WA trial program only
lasted for 14 weeks, the technology and method employed was different, and cost structures
are likely to have changed due to the passage of time.
9The metropolitan region
This metropolitan region encompasses the same metropolitan region taken from the WA
Government’s 2014 trial drumline program (i.e. from Quinns Rock Beach to Warnbro Beach),
but extends it further south to include Mandurah. This approach could provide additional
protection to Mandurah residents, particularly given that there have been a number of recent
shark encounters in the area, including one fatality in 2016.
For illustrative purposes, this map zooms in on an iconic stretch of beaches along this region’s
coastline from Cottesloe beach to Scarborough beach.
Cottesloe to Scarborough
Cottesloe and Scarborough are among Perth city’s most iconic beaches and, due to their natural
beauty and proximity to Perth, they are popular with local families and WA tourists.
There have been shark attacks documented along the stretch from Cottesloe to Scarborough,
with fatal shark attacks having occurred at Cottesloe beach in both 2000 and 2011. In 2005, a
surfer at Scarborough beach was unharmed in a shark encounter.
To offer swimmers greater protection from sharks, the Scarborough to Cottesloe area could
benefit from the introduction of SMART drumlines. For example, this could involve the
deployment of 23 SMART drumlines to cover the stretch from Cottesloe beach to Scarborough
beach.
Based on the costs of NSW Government’s trial, the cost could be from $650,000 to $900,000 for
the operation of the 23 SMART drumlines for a six month period.
10The South-West region
The South-West region replicates the second region targeted under the WA Government’s 2014 trial
drumline program (from Forrest Beach to Prevelly). However, the region has been adjusted to
include the Bunbury coastline, which has seen a number of fatal and non-fatal shark attacks in
recent years. For illustrative purposes, this map zooms in on two iconic swimming and surfing areas:
Yallingup and Gracetown to Prevelly.
Yallingup
Yallingup is a popular spot on WA’s South-West coast for swimmers, surfers and snorkelers.
Suspected Great White Shark attacks have been recorded at Yallingup beaches, including a shark
encounter at Injidup beach in 2006 (the surfer was uninjured). In 2001, a beach-goer was uninjured
following an encounter by a Great White Shark at Honeycombs beach.
Greater shark protection could be provided in the Yallingup area with the introduction of SMART
drumlines, as indicated in the map. To cover a targeted area including Yallingup beach, Smiths
Beach, Canal Rocks and Injidup beach, 10 SMART drumlines could be deployed. Based on the
costs of NSW Government’s trials, the cost could be from $290,000 to $400,000 for the operation of
the SMART drumlines for a six month period.
Gracetown to Prevelly
The South-West coast is a popular area for swimmers and surfers. The area provides a number of
swimming spots and offers world-class surf breaks, with Surfer’s Point at Prevelly home to the
Margaret River Pro; the World Surf League’s World Championship Tour event.
There have been a number of shark attacks in the area, with two surfers killed by sharks at
Gracetown (2013 and 2004). There have also been four shark attacks in the area so far in 2018
(three at Gracetown and one at Prevelly). This year’s Margaret River Pro event was cancelled as a
result of shark attacks which occurred near the event.
To provide better protection to swimmers and surfers along the Gracetown to Prevelly coastline, 21
SMART drumlines could be deployed to cover the coastal area. The cost could be from $600,000 to
$820,000 for the operation of the SMART drumlines for a six month period.
11Why these regions have been highlighted
The regions selected in the maps above have been chosen to build on the research and
analysis undertaken by the WA Government when it implemented its 2014 trial drumline
program. The beaches have been highlighted for illustrative purposes due to their popularity
with beach-goers and history of shark attacks and encounters.
The WA Government could consider other priority areas not captured in the zones above
based on expert understanding of local conditions, shark activity and shark sightings, and
community consultation. For example, in response to a fatal shark attack in April 2017, the WA
Government extended its shark monitoring network, which included the addition of two real-
time shark detection receivers, to Esperance on the southern coast of WA. The WA
Government could consider deploying SMART drumlines to the same region.
In addition, six fatal attacks have occurred outside of the two regions in WA in the last
25 years. These fatal attacks occurred in Roebuck Bay (Broome), Houtman Abrolhos Island
(off Geraldton), Wedge Island (north of Perth), Cheynes beach (Albany), Wylie Bay
(Esperance) and Starvation beach (Hopetoun). The deployment of SMART drumlines to these
locations is worthy of serious consideration by the WA Government.
Any approach taken by the WA Government should be viewed through the lens of the seven
broad principles at Appendix 1. These principles capture the elements that would reasonably
be expected in an effective shark hazard mitigation regime.
12APPENDIX 1
PRINCIPLES FOR EFFECTIVE SHARK HAZARD MITIGATION
Introduction
Though interactions between humans and sharks are rare, shark attacks can be extremely
traumatic and pose a serious risk to human life. As public safety is of paramount importance,
shark hazard mitigation strategies must provide effective protection for Australians while
minimising harm to sharks, other marine species and the environment.
It is the responsibility of state and territory governments to focus on public safety in their
waters and manage the risks to humans from sharks.
This document sets out seven broad principles that would reasonably be expected to be found
in an effective shark hazard mitigation regime. Examples are also provided where positive
actions are being taken to implement these principles across Australia.
Principles for effective shark hazard mitigation
1. There is community confidence in the safety of beaches
Successful shark hazard mitigation strategies ensure communities have confidence in the
mitigation measures being implemented and the safety of their local beaches.
The NSW Government has developed the SharkSmart phone app to provide key information
and resources to users to help educate the public and reduce the likelihood of shark
encounters. The app provides alerts about shark-related incidents, real-time information about
tagged sharks from shark listening devices, and information about dangerous and non-
dangerous sharks for education purposes.
The Western Australian Government has developed a Shark Activity map, available on their
Shark Smart website. The map shows current alerts and warnings (including shark advice for
particular beaches), reported sightings, and the latest shark detections to help the public make
informed decisions about their water use.
2. Best practice and emerging technologies are used for surveillance, detection and
deterrence of sharks while minimising harm to threatened or protected species
For shark hazard mitigation strategies to be fully effective, state and territory governments
should consider an integrated shark management strategy that includes a range of
scientifically-informed management actions and emerging technologies to increase protection
for beach-goers. This should include learning and sharing information from other states or
territories to understand what measures have been effective. Priority should be given to the
use of technology that minimises harm to matters of national environmental significance.
For example, the NSW Government began trialling the use of SMART (Shark Management
Alert in Real Time) drumline technology in 2015. SMART drumlines are an emerging
technology that are designed to be non-lethal as they allow sharks and other marine life that
are caught to be tagged, relocated and released. Preliminary results from the NSW trials
indicate that SMART drumlines have proven to be effective in catching target shark species
(Great White, Tiger and Bull sharks) and minimising bycatch.
133. Take a risk-based approach, appropriate to local conditions
An effective regime for shark hazard mitigation should take into account local conditions,
identify the level of risk and develop appropriate mitigation strategies.
For example, the NSW Government used an evidence-based risk management approach to
identify the six regions where SMART drumlines were deployed. This approach was informed
by a combination of evidence sources including the presence of tagged sharks, the history of
unprovoked shark interactions, and sightings of sharks in aerial surveillance.
4. Be based on scientific research and data sharing
Engaging in and sharing scientific research ensures state and territory governments are best
placed to utilise innovative, emerging technologies to provide the most effective shark hazard
mitigation strategies to protect beach-goers.
The NSW Government’s 2015 Shark Management Strategy is scientifically driven and includes
competitive grants to foster innovation in new technologies, an expansion of shark tagging
operations by expert shark researchers to improve detection and reporting capabilities, trials of
SMART drumlines, and funding for university research projects aimed at protecting beach-
goers from shark hazards, such as research into shark detection and deterrence initiatives.
5. Communities are consulted and initiatives include education and awareness
activities
Community consultation, public education and awareness activities are essential to educate
the public about how individuals can minimise their risk of a shark attack.
For example, community consultation and engagement formed a key component of the NSW
Government’s SMART drumline trials. Community consultation helped to inform the beaches
selected for the trial, and surveys before and during the last month of the trial monitored the
community’s level of acceptance to the presence and operation of the strategy.
The Western Australian Government has implemented initiatives to improve community
understanding of shark activity including a community awareness and engagement program
and the Shark Smart website. The website provides the community with information about
shark activity, research projects and strategies to reduce the risk of shark encounters.
6. Regular evaluation and monitoring processes are in place
Regular evaluation and monitoring helps to ensure the most effective measures are being
implemented to protect beach-goers while minimising harm to sharks and other animals.
Evaluation and monitoring can be used to determine if the strategies are being implemented
properly and if objectives are being met, and can be used to guide the development and
implementation of future shark hazard mitigation measures.
For example, the NSW Government is undertaking a comprehensive mid-strategy review of its
innovative 2015-2020 Shark Management Strategy, which will help to inform ongoing research
and future implementation of emerging technologies.
147. Mitigation strategies are consistent with domestic and international laws
All steps taken to reduce the risk of shark attacks must abide by all applicable state, territory,
Commonwealth and International laws.
For example, under the Commonwealth’s Environmental Protection and Biodiversity
Conservation Act 1999 (EPBC Act) some shark species—including the Great White Shark—
are listed as ‘threatened’ due to declines in shark numbers. Any action that has, will have or is
likely to have a significant impact on a threatened species must be referred to the Department
of the Environment and Energy for assessment before the action goes ahead.
Many shark hazard mitigation measures, such as SMART drumlines and shark surveillance
drones, do not have significant impacts on matters of national environmental significance.
However, in some cases where this may not be the case (e.g. the use of mesh netting), it is
open to a person to apply for an exemption from the EPBC Act if it is in the national interest for
the action to go ahead. In determining whether to grant a national interest exemption for shark
mitigation, the Minister’s considerations could include human safety, socio-economic impacts,
scientific evidence for the proposed approach, and how long the approach will be used for.
In addition, the Great White Shark is protected internationally through a number of
mechanisms. It is listed on Appendix II of the Convention on International Trade in
Endangered Species of Fauna and Flora (CITES) and also on Appendices I and II of the
Convention on Migratory Species (CMS). These conventions limit trade and help reduce the
number of sharks killed through commercial and recreational fishing activities.
15Endnotes
i
Australian Government (9 February 2018) Statement from Federal Minister for the Environment and Energy Josh Frydenberg
[media release]. Retrieved from
ii
CSIRO 2016, Milestone Report Project A4: The status of human-shark interactions and initiatives to mitigate risk in Australia.
Report to the National Environmental Science Program, Marine Biodiversity Hub. CSIRO Oceans & Atmosphere.
iii
The South Australian Government 2017, The Senate Environment and Communications References Committee - Inquiry into the
efficacy and regulation of shark mitigation and deterrent measures – Submission from the South Australian Government,
Adelaide.
iv
The Queensland Government’s Department of Agriculture and Fisheries 2017, Queensland Government response to Senate
referred inquiry into the efficacy and regulation of shark mitigation and deterrent measures, Brisbane.
v
CSIRO 2016, Milestone Report Project A4: The status of human-shark interactions and initiatives to mitigate risk in Australia.
Report to the National Environmental Science Program, Marine Biodiversity Hub. CSIRO Oceans & Atmosphere.
vi
Government of Western Australia (13 May 2017) [media release]. Retrieved from
vii
The New South Wales Government’s Department of Primary Industries shark management website
viii
New South Wales Government’s Department of Primary Industries, Snapshot of the first North Coast Shark Net Trial results,
viewed 7 June 2018,
ix
Data sourced from the Australian Shark Attack File as supplied by Taronga Conservation Society Australia. Data is accurate as
at 6 June 2018.
x
Bruce et al. 2018. A national assessment of the status of white sharks. National Environmental Science Programme, Marine
Biodiversity Hub, CSIRO.
xi
Bruce et al. 2018. A national assessment of the status of white sharks. National Environmental Science Programme, Marine
Biodiversity Hub, CSIRO.
xii
Data sourced from the Australian Shark Attack File as supplied by Taronga Conservation Society Australia. Data is accurate as
at 6 June 2018.
xiii
The Government of Western Australia’s Department of the Premier and Cabinet 2014, Review of the WA Shark Hazard
Mitigation Drum Line Program 2013-14, Perth.
xiv
The Government of Western Australia’s Department of the Premier and Cabinet 2014, Review of the WA Shark Hazard
Mitigation Drum Line Program 2013-14, Perth.
xv
The Government of Western Australia’s Department of the Premier and Cabinet 2014, Review of the WA Shark Hazard
Mitigation Drum Line Program 2013-14, Perth.
xvi
New South Wales Government’s Department of Primary Industries (13 February 2018) [media release]. Retrieved from
xvii
New South Wales Government’s Department of Primary Industries, Snapshot of the first North Coast Shark Net Trial results,
viewed 7 June 2018,
xviii
Calculations are based on publicly available tender and contract information for the NSW SMART drumline trials; specifically
costs for the Kiama to Shell Cove region of $335,000 (based on 10 SMART drum lines over six months) and costs for the
Ulladulla to Narrawallee region of $242,000 (based on 10 SMART drum lines over six months). The figures have been used to
estimate the high and low cost ranges for the regions for the purpose of this document, noting the ranges could differ depending
on tender outcomes and local conditions.
xix
New South Wales Government’s Department of Primary Industries (17 May 2018) Statement from Minister for Primary
Industries Niall Blair [media release]. Retrieved from
16You can also read
