Submarine Cable Protection and the Environment - (ICPC) A Publication from the International Cable Protection Committee
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A Publication from the International Cable Protection Committee (ICPC) March 2021 ~ Issue #2 Submarine Cable Protection and the Environment An Update from the ICPC, Written by Marine Environmental Adviser, Dr Mike Clare
3
Editor’s Corner
4
Introduction
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT
An Update from the ICPC, Written by the Marine
6
Warming Oceans Environmental Adviser (MEA)
and Changing
Fishing Practices PUBLISHER
The International Cable Protection Committee (ICPC)
11
Fish Aggregating
AUTHOR
Devices: An
Dr Mike Clare
Emerging Threat
ICPC Marine Environmental Adviser
for Submarine
Also, Principal Researcher – Ocean BioGeoScience at the
Telecommunication
National Oceanography Centre, UK
Cables
19
EDITOR
Improved Cable
Mr Ryan Wopschall
Design Eliminates
ICPC General Manager
the Threat Posed
by Sharks to
DESIGN & LAYOUT
Submarine Cables
Ms. Christine Schinella
24
ICPC Secretariat
About the ICPC
& Editorial Staff CONTACT
PO Box 150 Lymington SO 41 6WA UK
25
Website: www.iscpc.org
Further Reading Secretariat: secretariat@iscpc.org
& References LinkedIn
2 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021
EDITOR’S CORNER
Our modern lives rely upon
these critical seafloor assets more
The submarine cable industry has than ever. Though the global
changed substantially in the last ten network of submarine cables is
years to support increasing designed to be resilient through
worldwide demands for data ensuring a redundancy and
transfer and communications. diversity of cable routes and
Cable ownership has shifted, new landings, it is important to be
routes have been and are being aware of future changes in human
developed, and fibre count for activities that can interact with
even the longest trans-oceanic submarine cables. It is the goal of
systems is increasing. This coupled the International Cable Protection
with an increase in capacity per Committee (ICPC) to keep the
fibre pair has enabled the data- world connected by working to
driven growth across our global protect submarine cables in
network. coordination with other seabed
Despite the expansion of this users. As a result, the ICPC is
critical network, the nature of growing and evolving, with the
events that can damage formation of new working groups to
submarine cables around the world address today’s concerns, and the
has not changed dramatically over development of new recommend-
the last decade, or even the dations to provide guidance to the
previous decade. Inadvertent industry. Our goal is to ensure the
human related activity still poses the global network stays resilient.
largest risk of damage to submarine It is our pleasure to share with
cables, with bottom contact fishing you this second issue of Submarine
being the predominant contributor. Cable Protection and the
But what is changing is the nature Environment.
of fishing activity itself, as well as
Sincerely,
the uses of the world’s oceans and Ryan Wopschall
the seafloor. ICPC General Manager
3 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021
INTRODUCTION
More than 1.8 million kilometres during their lifespan, which is usually
of telecommunications cables about 25 years or longer1.
cross the global ocean, carrying Every year around 100 to 200
telephone calls, data, documents, cases of damage are reported on
and video calls, enabling the the submarine cables that comprise
internet, access to cloud storage, the global submarine
and underpinning financial trading telecommunications cable network.
worldwide. Most of these cables lie Repairs can be expensive and
in deep water, where they sit logistically-challenging—particularly
directly on the seafloor without any if the fault lies below thousands of
armouring. These polyethylene metres of water. However, repairs in
lined cables are similar in size to a the deep water of the High Seas are
garden hose (17-21 mm diameter). quite rare; averaging fewer than
They largely remain untouched four instances per year worldwide.
4 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021
INTRODUCTION
Damage caused by underwater deeper waters due to depletion of
landslides or earthquakes tend to stocks by overfishing and because
make more exciting headlines2, but of the impacts of ocean warming
natural hazards account for less than on fish habitats4. Understanding
10% of all documented faults (see future trends in fishing activity, and
Figure 1 on page 7). A global mitigating against any adverse
database of more than five impacts, is therefore of key
thousand cable faults, analysed by importance to the submarine
the ICPC since 1959, reveals that cable industry. In this second issue
most cable faults occur in shallow of Submarine Cable Protection and
water (less than 100 m) and are the Environment, we focus on the
instead related to more mundane interactions between submarine
causes: accidental human cables and fishing, highlighting the
interactions. Human activities following topical issues:
account for more cable faults than
any other category, with fishing ► Changing trends in fishing
accounting for nearly half of all the and interactions with
reported faults in the database submarine cables.
(Figure 1). This is perhaps unsurprising,
and given the on-going expansion ► How improved cable design
of human activity in the ocean, has already removed the
which is mostly focused on the threat posed by sharks to
continental shelf, activities such as submarine cables.
maritime transport, hydrocarbon
exploration, dredging, hydrocarbon ► The identification of an
exploration, marine research and emerging and growing
fishing are likely to increase3. hazards for submarine
cables: fishing using Fish
Fishing intensity continues to
Aggregating Devices (FADs).
grow for food security and is
shifting to new locations and
5 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021
WARMING OCEANS AND CHANGING
FISHING PRACTICES (pages 6-10)
Bottom contact fishing occurs result of sheer luck, however. The
on most of the world’s continental submarine cable industry, and the
shelves and extends on the ICPC, have been proactively
adjacent continental slopes to engaging fisheries for decades,
water depths of 1,500 m or more5. promoting the awareness of
Despite the thousands of fishing submarine cables, ensuring both
vessels that operate worldwide, seabed user groups can exist side-
and hundreds of cables present in by-side in cooperation and
these depths, it is remarkable that harmony. That being said, the
interactions are relatively fishing-related cable faults (50-100
infrequent1. Many cables operate per year) can have major impacts
for years or decades without faults, as they can disrupt
and most fishing vessels never communications; particularly
interact with cables. This is not the affecting countries that rely on a
6 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021
WARMING OCEANS AND CHANGING
FISHING PRACTICES (pages 6-10)
small number of cable THE WIDESPREAD USE OF BOTTOM
connections. Submarine cables TRAWLING
are critical for global Historically, bottom trawling has
communications as they transmit been the main type of fishing to
more than 99% of all digital data interact with submarine cables as it
traffic worldwide. Satellites currently occurs on most continental shelves
lack the bandwidth and a direct and covers large areas of seafloor5.
connection via our world’s oceans This mode of fishing involves
is still the most effective link for both dragging an assembly of lines and
capacity and latency1. netting behind a vessel. Cable
faults tend to relate to the impacts
of the trawl doors (known as
Figure 1: Percentage of cable faults otterboards) that are dragged
related to different causes, based on along the seafloor, and weights
analysis of a global database kept that are designed to stir up the top
since 1959 (Courtesy of Global Marine).
few centimetres of the seafloor
Improvements in modern cable design
are thought to have removed the risk
sediment to capture fish and
of fish bites as discussed on page 19. shellfish. Otterboards can range
7 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021
WARMING OCEANS AND CHANGING
FISHING PRACTICES (pages 6-10)
from 100 kg to eight tonnes weight than 60 cm into the sediment in
for the largest commercial trawlers water depths down to 1000 m
and tend to penetrate between providing greater protection and
5 to 20 cm into the seafloor reduction in fault rates1. Even when
sediment, but may locally reach cables lie on the seafloor, trawl
50 cm or more in very soft contact may be light enough for
sediments5,6. Fishers try to avoid the gear to pass over the cable
deep seafloor penetration as it with no discernable contact. Firmer
can lead to damage of fishing contact may occur if a heavy
gear and slows progress. The otterboard or ground gear scrapes
environmental damage caused across a cable lying on rocks or
by deep sea trawling is also of other hard seafloor. However,
growing concern, as it can fishing vessels are pushing into
damage important seafloor deeper water, and burial in water
ecosystems, and release large depths of up to 1,500 m can be
quantities of buried carbon common in certain areas around
that counteracts climate the world.
change mitigation measures7,8,9, The main instances of fishing-
a topic recently presented related cable damage include:
to ICPC Members in an
Environmental Bulletin.
► If fishing gear or an anchor
IMPACTS OF TRAWLING ON hooks or snags on a cable, it
SUBMARINE CABLES may become damaged due
to bending, crushing, or
Research indicates that when a
stretching.
trawl crosses a telecommunication
cable on the seabed, more than
► A sharp corner of the fishing
90% of such crossings do not result
gear can penetrate cable
in any cable damage1,10. The
armour and insulation, or
armour may provide sufficient
bend or crush the glass fibres
protection to avoid damage. Many
within the cable.
modern cables are buried more
8 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021
WARMING OCEANS AND CHANGING
FISHING PRACTICES (pages 6-10)
► If a grapnel is deployed to these aspects increase the risk
recover lost fishing gear. In of cable damage where activities
many areas, normal fishing coincide.
gear may present almost
OTHER TRENDS AND FUTURE
no risk, but if a grapnel is
CHANGES IN FISHING
deployed, the risk
becomes extreme. Depletion of fishing stocks,
driven by overfishing, has created
GREATER THREATS IN GREATER changes in fishing practices in
WATER DEPTHS some regions, stimulating a push
Cables are more susceptible to into deeper waters9. This change
damage in deeper water as it has necessarily triggered an
becomes more challenging to bury increase in the water depths where
them. Heavily armoured cable is cables are buried in some
also harder to deploy in very deep locations, such as the north-east
water, so cables in deep water Atlantic and the eastern Pacific
tend to carry less or no armour1. In Ocean, where cables are
contrast, fishing gear in deeper sometimes buried in water depths
water tends to be heavier, often up to 2,000 m13. As a cable’s design
using large anchors. It is also more life is 25 years, it is important to
common for fishers to drag grapnels consider future changes in fishing
to retrieve fishing gear from fixed practices and in which water
locations in deep water1. All of
Figure 2: Photograph of damage
caused to a telecommunications cable
by deep-sea trawling (from Carter et al.,
20091).
9 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021
WARMING OCEANS AND CHANGING
FISHING PRACTICES (pages 6-10)
depths they will most likely occur. sometimes at almost 5,000 m1. This
Recent years have seen a growth type of fishing includes the growing
in cable faults caused by fishing and widespread use of Fish
activities using gear that is fixed in Aggregating Devices that forms
one place—largely in water depths the basis of discussion on page 11
of between 500 m and 1800 m, but of this issue.
FOOD FOR THOUGHT
There are several factors which are pushing fishing into deeper water
depths or areas in which fishing has not previously been so common.
► Human-induced climate change is driving the migration of a
number of key species towards cooler waters, which in turn will
affect the location of fishing grounds10,11,12.
► Recent modelling of future climate change scenarios indicates
that deep-sea fish habitats will likely move between two to nine
degrees towards higher latitudes4.
► Implications of this migration are that cables may require
protection in areas and jurisdictions that have historically not
been fished before.
► Understanding how climate change will affect fishing activity
is therefore of particular interest to the submarine cable industry.
10 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021FISH AGGREGATING DEVICES: AN EMERGING THREAT FOR
SUBMARINE TELECOMMUNICATION CABLES (pages 11-17)
THIS ARTICLE INCLUDES known to increase the efficiency of
CONTRIBUTIONS FROM THE fishing for large commercially-
MEMBERS OF THE ICPC FISH
valuable fish, and their use has
AGGREGATING DEVICE WORKING
grown dramatically in recent
GROUP (FAD WG)
decades. As an example, the
For centuries, fishers have used
introduction of FADs to support
floating objects such as logs and
tuna fishing in the Philippines in
other debris to attract fish, as they
1975 increased tuna production
tend to congregate near them for
from 10,000 to 125,000 tonnes
shelter. These smaller fish then
per year, growing employment
attract larger catches, such as
across the country’s fishing industry
marlin and tuna. Fishing of these
and increasing food security15.
catches can be lucrative. The
FAD use is most common in the
global trade in tropical tuna was
Indian Ocean and eastern Pacific
reportedly worth about $32 billion
Ocean, but is increasingly
in 2019 alone14. Purpose-built
observed in other regions.
floating structures (known as Fish
Aggregating Devices; FADs) are
11 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021FISH AGGREGATING DEVICES: AN EMERGING THREAT FOR
SUBMARINE TELECOMMUNICATION CABLES (pages 11-18)
► While there are many ► This damage is often at far
benefits of fishing using FADs, greater water depths (up to
a number of environmental 5,000 m) than the fishing-
concerns have been related interactions that the
highlighted by various industry has had to deal with
studies16-21 such as the historically.
growing legacy of lost fishing
gear that is primarily made of This article covers some of the
plastic and litters the key points about FADs, including
oceans22. their global distribution, their
benefits, and the emerging threats
► Fishing using FADs is also of they pose to submarine cables.
increasing concern to the
submarine cable industry, as
several companies have
Figure 3: A Fish Aggregating Device
reported damage to
showing the underside of the floating
telecommunication cables platform. (Credit: WorldFish; available
from FADs. under a Creative Commons Licence)
12 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021FISH AGGREGATING DEVICES: AN EMERGING THREAT FOR
SUBMARINE TELECOMMUNICATION CABLES (pages 11-18)
11-17)
WHAT ARE FISH AGGREGATING 3. A mooring line that is
DEVICES? typically made of
FADs consist of a surface buoy polyethylene or
or float from which fishing gear is polypropylene; however, the
deployed and may be crewed by upper 40 m or so may be
a fisher or left unattended. Some made of wire. Mooring lines
FADs are designed to drift across are deployed to 5,000 m
the ocean, tracked by a GPS water depth or more in
transponder. Others are tethered to regions of the world where
the seafloor and are known as deep anchored FADs are
anchored or moored FADs, which being used.
typically include four components:
1. A float made of bamboo, Figure 4: Schematic showing the
plastic, or other buoyant main components of an anchored Fish
Aggregating Device (not to scale).
material. This is the only part
of a FAD visible on the sea
surface.
2. Sub-surface structures that
provide shade and shelter to
attract fish. These tend to
comprise large leaves,
seaweed, or synthetic
materials such as plastic
sheeting or discarded fishing
nets. As these attractors can
be attached to the surface
float or the mooring line,
they are placed at a range
of water depths from 20 m
to 1500 m.
13 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021FISH AGGREGATING DEVICES: AN EMERGING THREAT FOR
SUBMARINE TELECOMMUNICATION CABLES (pages 11-18)
4. An anchor to keep the FAD become caught by accident
mooring in place, which is (known as ‘by-catch’). A recent
typically made of rocks, cast WWF report indicated that FAD
concrete blocks or heavy- fishing was responsible for up to four
duty chain. times more by-catch than fisheries
targeting free-swimming schools of
ENVIRONMENTAL ISSUES
fish in the Atlantic, Indian, and
The use of FADs has been widely eastern Pacific Ocean16. In the
promoted in many regions, western Pacific, this figure grows to
including the western and central seven times. While their use is often
Pacific, Indian Ocean, Caribbean regulated and managed at a
Sea, Mediterranean Sea; however, national to regional level, illegal
their use is limited in the north FAD use is commonplace in several
Atlantic17,22,23. Their use is promoted regions19. Unregulated and overuse
because: of FADs may severely impact
► FADs remove the need to fish sustainable fishing in the future,
close to dolphin herds or leading to collapse of local
around coral reefs17. fisheries or pushing activities into
deeper water18.
► The higher catch efficiency
Once they reach the end of
leads to greater profitability16.
their life (typically a few months, to
► Individual fish species can be
years at most), the hundreds to
more effectively targeted,
thousands of metres of fishing gear
which reduces pressure on
and plastic rope associated with
free-swimming schools of fish
FADs become discarded in the
that include more vulnerable
ocean. This ‘ghost gear’ can drift
species19.
across the oceans or become
The efficiency of FADs in snagged on the seafloor and will
aggregating fish also means that last for prolonged periods of time24.
other non-commercially valuable In the central Mediterranean,
species are attracted and can seafloor surveys found that most of
14 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021FISH AGGREGATING DEVICES: AN EMERGING THREAT FOR SUBMARINE TELECOMMUNICATION CABLES (pages 11-18) the litter observed came from FADs materials in FAD design, but and was wrapped around biodegradable FADs tend to be protected corals22. Efforts are less durable, and therefore have a underway to mitigate this issue, shorter lifespan25. through the use of biodegradable Figure 5: Photographs acquired from surveys showing marine litter on the western Mediterranean seafloor (from Consoli et al., 202022). a) FAD ropes under tension; b) FAD rope anchored to limestone block, entangling corals; c) corals entangled by rope; d) corals growing on a FAD-anchor; e) other litter observed i.e., plastic bag; f-h) live colonies of corals and dead branches entangled by ropes. 15 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC) SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021
FISH AGGREGATING DEVICES: AN EMERGING THREAT FOR
SUBMARINE TELECOMMUNICATION CABLES (pages 11-18)
FEW AREAS OF THE OCEANS ARE WHAT THREAT DO FISH
FREE FROM FISH AGGREGATING AGGREGATING DEVICES POSE
DEVICES TO CABLES?
The use of FADs has increased While floating fishing gear may
globally over recent decades; not seem that dangerous,
largely driven by the efficiency of submarine cable owners have
this fishing method, as well as due started to identify their impacts.
to public and policy steer25-28. Their Examples from the last few years in
presence in tropical seas is the Indian Ocean and offshore
becoming more ubiquitous and a south-east Asia involved snagging
2011 review estimated that FADs of durable plastic fishing lines, and
were used for over 40% of world metal link connections, around
tropical tuna catches. Approx- cables in water depths of between
imately 73,000 anchored FADs and 2,000 and 4,000 m. Cables can be
between 81,000 and 121,000 abraded by direct contact with a
drifting FADs are estimated to be mooring line, causing damage to
deployed annually29-31. the outer cable sheath, and
compromising the insulation of the
electrical conductor resulting in a
The number of lost FADs short circuit known as a shunt fault1.
Some faults occurred
and ghost gear that drifts
instantaneously, as the subsurface
below of the ocean surface
fishing line became wrapped
is a vast number. It is around the cable, while others
perhaps not surprising that developed over several years,
reports of interactions which may relate to the long-term
effects of abrasion, or due to gear
between the cables that
that became entangled as it was
span the world’s oceans transported by storms or seafloor
and FADs are on the rise. currents. FAD-related damage can
occur during installation, when
16 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021FISH AGGREGATING DEVICES: AN EMERGING THREAT FOR
SUBMARINE TELECOMMUNICATION CABLES (pages 11-18)
cables are repaired, or at any point Cable owners and their system
during their approximately 25-year suppliers and installers have
lifespan. Some owners have also experienced an increasing number
reported damage from FAD of cable faults from FADs over the
anchors; either from accidental last few years. This is particularly
dropping of the concrete weight true where new cables are being
on the cable itself, or as a result deployed along new and diverse
of impact when a moored FAD cable routes where FAD use is both
was dragged over the cable widespread and also poorly
when moved by vigorous ocean mapped or documented. As a
currents. result of this trend, the ICPC
established a FAD Working Group
FADs also pose a hazard to
towards the end of 2020, where
other activities that support the
ICPC Members are working
submarine cable industry16. As FADs
collaboratively to define the risk
are often only marked above the
of FADs to cables and their
water by a small float, they are
associated activities, determine
difficult to spot at sea, and cannot
mitigation measures for these risks,
be spotted at all if they have lost
and develop a strategy for
their surface platform. The mooring
outreach and liaison efforts, as
lines are extremely strong and can
well as developing best practice
also become snagged around ship
guidance for governments
propellers and expensive towed
that oversee and monitor
equipment that is used to survey
FAD deployments.
the seafloor.
The submarine cable industry is exploring improvements to
cable design to increase resilience to FAD-related impacts;
however, the most effective and immediate mitigation
measures will most likely relate to highlighting the issues above
and through raising awareness.
17 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021FISH AGGREGATING DEVICES: AN EMERGING THREAT FOR
SUBMARINE TELECOMMUNICATION CABLES (pages 11-18)
FOOD FOR THOUGHT
Some of the ongoing measures to reduce the risks posed by FADs
to submarine cables include:
► Assessing the likelihood of encountering FADs based on local
fishing practices and previous experience in the region. This is
best done as part of a desktop study during the planning
stage and through liaison with fisheries organisations and
representatives.
► Identifying and liaising with FAD owners, such as through
national databases.
► Modifying pre-installation surveys for locating FADs.
► Considering different methods for avoiding, removing, or
relocating FADs, where necessary, to minimize the likelihood
of interactions.
► Increased armouring of the cable, including in deeper water,
to mitigate against the abrasion risk during installation.
► Carrying enough spare cable in FAD-prone areas during
installation and repair operations if any damage occurs.
18 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021IMPROVED CABLE DESIGN ELIMINATES THE THREAT POSED
BY SHARKS TO SUBMARINE CABLES (pages 19-22)
So far, we have discussed the During the period dominated by
impacts of fishing on submarine submarine telegraphic cables
cables, but what about fish (between 1901 and 1957), at least
themselves? Can shark attacks 28 cables were damaged by fish
cripple the internet? Analysis of bites1,33. These bites were mostly
past cable damage shows that, attributed to sharks, as determined
while biting fish including sharks from teeth found embedded in
may have been responsible for a cable sheathings, as well as other
small number of cable faults, these fish such as barracuda. Bites
events have declined over time, tended to penetrate the cable
with no such events occurring in insulation, allowing infiltration of
recent decades. seawater, and causing the internal
power conductor to ground. These
attacks mainly took place in
❖ Pre 1957: Shark attacks on relatively shallow water, on the
telegraphic-era cables in continental shelf and continued
shallow water: to the coaxial cable era.
19 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021IMPROVED CABLE DESIGN ELIMINATES THE THREAT POSED
BY SHARKS TO SUBMARINE CABLES (pages 19-22)
❖ 1959-2006: Deeper water shark 1,900 m34. At the time this
attacks on coaxial and fibre- accounted forIMPROVED CABLE DESIGN ELIMINATES THE THREAT POSED
BY SHARKS TO SUBMARINE CABLES (pages 19-22)
up to 2000 m, while design ❖ Whale-related faults have also
improvements have been made to ceased due to improved
the outer protective cable cable design:
sheathing to include metal tape.
Improvements to cable design
These improvements in cable also eliminated the number of
protection appear to have cable faults caused by whales.
eliminated the problem as records Between 1877 and 1955, 16 faults
since 2006 (analysed here to the were thought to have been
end of 2020) provide no evidence caused by whales that became
of any cable faults linked to sharks entangled by submarine telegraph
or other fish bites (Figure 6). It is cables38,39. Of these, thirteen were
unlikely that shark bites are missed linked to Sperm whales as their
from this recent analysis, as remains were found within the
previous damaging attacks left cables, and most occurred at the
clear evidence in the form of teeth edge of the continental shelf and
imprints or teeth embedded in the the adjacent continental slope.
cable’s outer polyethylene sheath. Recent analysis provides no
evidence for any whale
Figure 7: Photograph of a crocodile entanglements since 1959,
shark: one of the species of shark however32. This absence of
known to have previously damaged entanglements is also related to
cables. Reproduced under a Creative
improvements in modern cable
Commons license (Source:
https://fishesofaustralia.net.au/home/ design, laying and maintenance,
species/3001 ). including: i) reducing the coiling of
21 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021IMPROVED CABLE DESIGN ELIMINATES THE THREAT POSED
BY SHARKS TO SUBMARINE CABLES (pages 19-22)
cables when laid on the seafloor
and after repair; ii) using accurate FOOD FOR THOUGHT
seafloor surveys to avoid rough
seafloor where cables are more
Of all the documented
prone to become suspended or
looped; iii) burial of cables below cable faults worldwide, fish
the seafloor in water depths of up
bite-related faults account for
to 2,000 metres, which is the typical
diving depth of sperm whales1,40,41. a tiny proportion of damaging
events (0.1% of the total), which
As noted in the article on page 11,
titled: “Fish Aggregating Devices: An pales in comparison to other
Emerging Threat for Submarine
fault types (e.g. fishing, anchor
Telecommunication Cables,”
information was also provided by drops and geological hazards).
ICPC’s Fish Aggregating Device (FAD)
Lessons learned from past
Working Group. The FAD Working
Group is one of nine Working Groups attacks prompted
where ICPC Members are involved. If
your organisation is interested in
improvements to cable
becoming a Member (or is currently a
design that has removed the
Member) of the ICPC, you have the
opportunity to participate in the threat posed by shark and
following groups: Affiliations, Biodiversity
other fish attacks.
Beyond National jurisdiction (BBNJ),
Business Planning, Cable Security
(currently at full capacity), Charting,
Media & Public Relations, Mining, and
the Recommendations Steering Group.
Any enquiries, please send an e-mail to:
secretariat@iscpc.org.
22 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021Please visit www.iscpc.org for further information.
Sharing the seabed in harmony with others
The International Cable Protection Committee (ICPC) was formed in 1958 and its primary goal is to promote
the safeguarding of international submarine cables against human made and natural hazards. The
organisation provides a forum for the exchange of technical, legal and environmental information about
submarine cables and, with more than 170 MEMBERS from over 60 NATIONS, including cable operators,
owners, manufacturers, industry service providers, and governments, it is the world’s premier submarine cable
organisation. The ICPC comprises of an 18 Member Executive Committee (EC)-led organisation voted in by its
Full Members. In addition to the Marine Environmental Adviser (MEA), General Manager (GM) and Secretariat
team, the ICPC also has an appointed International Cable Law Adviser (ICLA) as well as a United Nations
Observer Representative (UNOR).
Prime Activities of the ICPC:
• Promote awareness of submarine cables as critical infrastructure to governments and other users
of the seabed.
• Establish internationally agreed recommendations for cable installation, protection, and
maintenance.
• Monitor the evolution of international treaties and national legislation and help to ensure that
submarine cable interests are fully protected.
• Liaison with UN Bodies.
Recommendations:
• Taking into account the marine environment, the ICPC authors Recommendations which
provides guidance to all seabed users ensuring best practices are in place.
• Educating the undersea community as well as defining the minimum recommendations for cable
route planning, installation, operation, maintenance and protection as well as survey operations.
• Facilitating access to new cable technologies.
Advancing Regulatory Guidance:
• Promoting United Nations Convention for the Law of the Sea (UNCLOS) compliance.
• Championing uniform and practical local legislation and permitting
• Protecting cable systems and ships.
• Aiding education of government regulators and diplomats.
Working with Science:
To learn how to become
• Supporting independent research into cables.
of Member organisation
• Publishing reviews for governments and policy makers.
• Working with environmental organisations.
of the ICPC, please
• Effective public education via various media. click on join here.
23 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021EDITORIAL STAFF
Author: Dr Mike Clare Editor: Ryan Wopschall
Ryan is the General Manager for
Mike is the Marine
the ICPC. He has spent the last 15
Environmental Adviser for the
years in the telecommunications
International Cable Protection industry with a focus on inter-
Committee (ICPC) and is a national undersea and terrestrial
backhaul telecommunications.
Principal Researcher at the
National Oceanography Centre,
UK, where he works as part of the
Ocean BioGeoscience Research
Group. His research focuses on
better understanding the dynamic
seafloor, the implications of past
and future climate change, Design & Layout: Christine Schinella
impacts of human activities, and As part of her Secretariat role,
quantifying risks to critical Christine coordinates marketing
infrastructure. Prior to his research activities for ICPC. With a
background in graphic design and
role at NOC, he worked for ten
publishing, Christine has been
years as a geohazard consultant to working in the telecommunications
a range of offshore industries. industry since 2000.
24 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021FURTHER READING & REFERENCES
impact on the status of the North Sea
Further information on submarine seafloor habitats. ICES Journal of Marine
Science, 77(5), pp.1772-1786.
cables and the marine environment
9. Paradis, S., Goñi, M., Masqué, P., Durán, R.,
can be found in the references and Arjona‐Camas, M., Palanques, A. and Puig,
P., 2021. Persistence of Biogeochemical
text within the peer-reviewed UNEP- Alterations of Deep‐Sea Sediments by
Bottom Trawling. Geophysical Research
WCMC report via: "Submarine Cables Letters, 48(2), p.e2020GL091279.
and the Oceans: Connecting the 10. Wilson, J., 2006. Predicting seafloor cable
faults from fishing gear – US Navy
World" as well as other resources via: Experience. Presentation at ICPC Plenary
Meeting, May 2006; Vancouver, Canada.
https://iscpc.org/publications 11. Stenevik, E.K. and Sundby, S., 2007. Impacts
of climate change on commercial fish
stocks in Norwegian waters. Marine
Policy, 31(1), pp.19-31.
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deep seafloor in the North East Atlantic: an
3. Jouffray, J.B., Blasiak, R., Norström, A.V.,
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expansion into the ocean. One Earth, 2(1), 14. Hanich, Q., Davis, R., Holmes, G.,
pp.43-54. Amidjogbe, E.R. and Campbell, B., 2019.
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Deploying, Soaking and Setting–When is a
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M.I., Villaseñor-Derbez, J.C. and Gaines,
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denitrification and has the potential to Modelling the impacts of fish aggregating
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small-scale fishery. ICES Journal of Marine
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Egekvist, J. and Garcia, C., 2020. Different Hall, S. 2020. The IUU Nature of FADs:
bottom trawl fisheries have a differential
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Markets. Coastal Management 48(6), shark mortality. Collect Vol Sci Pap
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20. Dagorn, L., Holland, K.N., Restrepo, V. and 29. Gershman, D., Nickson, A., and O’Toole, M.
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FADs? What are the real impacts of the use World: An Updated Analysis of Fish
of drifting FADs on pelagic marine Aggregating Devices Deployed in the
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21. Fauvel, T., Bez, N., Walker, E. et al. 2009 tuna fisheries (No.IP/B/PECH/IC/2013-123).
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Aggregating Devices (FADs) in the Western Filmalter J., Forget F., Sancristobal I., Holland
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22. Consoli, P., Sinopoli, M., Deidun, A., Canese, 32. Wood, M.P. and Carter, L., 2008. Whale
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2020. The impact of marine litter from fish telecommunication cables. IEEE Journal of
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IOTC-2009-WPEB-16, 22 pp.
41. Wood, M.P. and Carter, L., 2008. Whale
28. Franco, J., Moreno, G., López, J. and entanglements with submarine
Sancristobal, I., 2012. Testing new designs of telecommunication cables. IEEE Journal of
drifting fish aggregating device (DFAD) in Oceanic Engineering, 33(4), pp.445-450.
the Eastern Atlantic to reduce turtle and
26 A PUBLICATION FROM THE INTERNATIONAL CABLE PROTECTION COMMITTEE (ICPC)
SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021FURTHER READING & REFERENCES
14. Page 24: Credit, Schinella, Christine E.;
COPYRIGHTED IMAGE CREDITS:
Description: Humpback whale off the coast
1. Cover Image: iStock by Getty Images of Provincetown, Massachusetts, USA.
credit, richcarey; Description: School of
Bigeye Trevally fish (Jackfish) underwater 15. ICPC Logo: Copyrights/content appearing
beside Sipadan Island, Borneo. in this newsletter (images and text) belong
to ICPC or third parties granting ICPC
2. Page 3: iStock by Getty Images credit, permission to use the copyright written
Allexxandar; Description: Underwater blue and/or visual material and cannot be
ocean, sandy sea bottom, underwater altered or repurposed for one’s own use.
background. Written permission is required.
3. Page 4: iStock by Getty Images credit,
Chombosan; Description: Circle panorama
of urban city skyline, such as if they were
taken with a fish-eye lens.
4. Page 6: iStock by Getty Images credit,
Tammy616; Description: Jacks on reef.
5. Page 7: Image credit, Global Marine.
6. Page 9: Image credit, Professor Lionel
Carter.
7. Page 10, 18 & 22: iStock by Getty Images
credit, JuSun; Description: Earth map comes
from public domain www.nasa.gov.
8. Page 11: iStock by Getty Images credit,
RainervonBrandis; Description: Split level
image of fish aggregation device in the
water. Fish aggregation devices are used
by the fishing industry to attract fish out in
the open ocean. They are then netted, and
the catch may include sharks, turtles and
dolphins.
9. Page 12: Image credit, Creative Commons
Licence.
10. Page 15: Image credit, Consoli et al. 2020).
11. Page 19: iStock by Getty Images credit,
qldian; Description: Shark swimming over
reef with fish.
12. Page 20: Wood and Carter, 2008
13. Page 21: Reproduced under a Creative
Commons license.
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SUBMARINE CABLE PROTECTION AND THE ENVIRONMENT ● MARCH 2021You can also read
