Spearfishing- It is ecologically sustainable?

I was sent this research article the other day that was an interesting read:

Abstract
Spearfishing or underwater fishing is an activity that generates emotion and debate. Is it the most ecologically sustainable
method of catching a fish or is it an activity of environmental vandalism and needless slaughter? Proponents argue that
spearfishing is ecologically sustainable because a diver is restricted to shallow water, a diver is very selective and can target the
size and species of his\her capture without the negative impacts of other fishing methods such as bycatch, bait, loss of gear and
damage to habitat.
Scientific research supports the view that spearfishers catch a very small proportion of fish – less than 1% compared to
recreational and commercial fishers and that fishery indicators such as catch per unit effort (CPUE) and average weight have
remained stable over time. I present data from several surveys of spearfishing (mostly competitions) in South Australia, New
South Wales and Queensland which support these statements. Opponents argue that spearfishers have been partly responsible
for the decline of some species such as grey nurse sharks and also scare fish, which are important for scuba diver tourism.
This presentation overviews methods, catches and management of spearfishing throughout Australia. There have been major
changes in the past 50 years, such as the banning of SCUBA spearfishing, formation of the Australian Underwater Federation
(AUF) to self-regulate the sport, protection of large ‘icon’ species such as groupers and wrasses, increasing amount of marine
parks, and blue-water hunting for pelagic species. It is anticipated that there will be pressures for further restrictions on
spearfishing and these will be supported if there are valid environmental reasons, but will be opposed if they are biased and
unjustified.
It is concluded that the future management of spearfishing by voluntary organisations such as the AUF and statutory fisheries
departments appears to be based on sound principles of sustainability.

Introduction
Spearfishing or underwater fishing is an activity that
generates emotion and debate. Is it the most ecologically
sustainable method of catching a fish or environmental
vandalism and needless slaughter? Proponents
argue that spearfishing is ecologically sustainable
because a diver is restricted to shallow water, is
very selective and can target the species and size of
the target without the negative impacts of other fishing
methods such as bycatch, bait, loss of gear and
damage to habitat.
There is scant information on spearfishing. Scientific
research and anecdotal information supports the view
that spearfishers catch a small proportion of fish -
less than one percent compared to recreational and
commercial fishers, and that fishery indicators such
as catch per unit effort (CPUE) and average weight
have remained stable over time. We present data from
several surveys of spearfishing (mostly competitions)
in South Australia (SA), New South Wales (NSW)
and Queensland (Qld) which support these state-
SPEARFISHING – IS IT ECOLOGICALLY
SUSTAINABLE?
Adam Smith1 and Seiji Nakaya2
1 Australian Underwater Federation (AUF) C\ 4 Seaward Cres, Townsville QLD 4810, Australia
2 Department of Environment, PO Box 917, Nuku’alofa, Tonga
ments, and we provide some long-term data on CPUE
and average weight of a popular species, the coral trout.

Methods and results
A search of the international scientific literature covering
1971-2001 indicated there were 84 200 articles on
fishing and only 145 of these had any reference to
spearfishing. The number of relevant articles is much
fewer. The first published scientific article on
spearfishing in Australia was by Saenger and Lowe
(1975) and there appears to have been only one PhD
thesis on spearfishing in Australia (Nakaya, 1999).
Most of the research has been on spearfishing competitions
in NSW or Qld (Table 1), using catch records
or questionnaires. Modern Australian spearfishing
competitions involve seven to 104 competitors
(Nakaya, 1999; Smith, 2000) and have restrictive rules
that allow only one of each eligible species to be taken
and also prescribe minimum weights during a set time
(generally five hours). Catch rates of 0.09 to 2.57 fish
per diver hour have been reported (Table 1).
CPUE is considered to be an indicator of fish density.
In theory, catch is proportional to fishing effort. Several
studies have been combined to analyse CPUE data
over a longer-term (Nakaya, 1999; Smith unpublished)
and there is no overall trend in CPUE or mean size of
several key species. However, it is interesting that the
CPUE of coral trout has been around 0.8 fish per diver
day since 1979, but appears to have declined by about
25% in recent years (Figure 1a). The average weight of
coral trout has remained fairly stable at 2.0kg from 1980
to 1992, but appears to have declined by some 25% to
about 1.5kg in 1995 and 2001 (Figure 1b). CPUE and
average weight of barramundi cod appear to have increased
slightly in recent years (Table 2). Some baseline
data on CPUE and average weight is provided on
three species of fish; maori wrasse, napolean parrotfish
and netted sweetlip, that were captured at a national
competition in 1994. These fish species were voluntarily
removed from the eligible list for the national competition
in 2001 (Table 2).
The annual Australian Blue Water Classic (ABWC) is
a selective spearfishing competition which targets large
pelagic species. The catch rates are very low with an
average of only one fish per day (Figure 2a) and an
average weight of 4 to 7kg (Figure 2b). There is no
trend in CPUE for fish or weight, although the most
recent year provided the highest values (Figure 2a-b).
A questionnaire was used to determine spearfisher’s
views about management of the Great Barrier Reef
Marine Park in general and whether they were satisfied
or dissatisfied with management of spearfishing
(Nakaya, 1999). Overall, about 50% were dissatisfied
with management because of weak controls on commercial
fishing compared with recreational fishing.
Specifically they were dissatisfied because they think
they are discriminated against by being excluded from
areas where line fishing is allowed (Nakaya, 1999).
Spearfishers were questioned also about their preferred
management tools. The respondents strongly supported
minimum size limits, preservation zones, bag
limits and patrols/enforcement (Figure 3), were equivocal
about stocking, rotational closures, maximum size
limit, exclusion of certain types of fishing, and seasonal
closures but opposed charges, licence, self-regulation
and strongly opposed exclusion of all fishing
(Figure 3).

Discussion and conclusions
There have been major changes in management of
spearfishing over the past 50 years, such as the banning
of SCUBA spearfishing, banning of commercial
spearfishing, formation of the Australian Underwater
Federation to self-regulate the sport, formal and informal
protection of large ‘icon’ species such as
groupers and wrasses (see Table 2), increasing numbers
of marine parks, and blue-water hunting for
pelagic species. These changes have occurred largely
without the support of scientific information. It is acknowledged
that good information is scarce, but available
information indicates that spearfishing provides
consistent results as there has been no demonstrable
changes in CPUE or average weight of key species
indicative of overfishing, although a recent 25% decline
in CPUE for coral trout in Qld waters may be of
concern. However, one of the difficulties in this example
is that it is difficult to attribute this potential impact
to spearfishing compared with the impacts of
other fishing methods on the same species.
It is surprising that about 50% of spearfishers in
Queensland are dissatisfied with management, but we
believe that this figure would be less in other parts of
Australia. It is suggested that managers need to consult
spearfishers specifically and review current, perhaps
inequitable, management arrangements.
Is spearfishing sustainable? A rigorous answer could
consider whether spearfishing satisfies the Commonwealth
Government requirements for a demonstrably
ecologically sustainable fishery, which must operate
under a management regime that meets two principles
(Environment Australia, 2002). The first principle is:
“A fishery must be conducted in a manner that does
not lead to over-fishing, or for those stocks that are
over-fished, the fishery must be conducted such that
there is a high degree of probability that the stock(s)
will recover”. We believe that spearfishing satisfies
this first principle and does not lead to overfishing
for most species. We have demonstrated stable CPUE
and consistent average weights of key species. Also,
there are over 440 species of fish that have been captured
by spearfishers (Smith, 2000) and we have been
able to find only anecdotal reports of local overfishing
for one or two species such as blue groper or cods,
with anecdotal and scientific evidence of recovery.
The second principle is: “Fishing operations should
be managed to minimise their impact on the structure,
Figure 3. Support and opposition by spearfishers to potential managing
tools.
SPEARFISHING – IS IT ECOLOGICALLY SUSTAINABLE? ADAM SMITH AND SEIJI NAKAYA
PAGE 22 3rd WORLD RECREATIONAL FISHING CONFERENCE. 21-24 MAY 2002. NORTHERN TERRITORY, AUSTRALIA.
productivity, function and biological diversity of the
ecosystem”. We believe that spearfishing satisfies this
second principle and perhaps, is one of the most ecologically
sustainable methods of fishing because it is
selective, is restricted to shallow water, has no bycatch,
uses no bait, causes no habitat damage, causes no
harm to endangered species and causes no pollution.
Spearfishing is a method that has been used to catch
fish for thousands of years. In modern times,
spearfishing has evolved to become a recreational activity.
The activity has been regulated heavily. It is
anticipated that there will be pressures (political and
emotional) for further restrictions on spearfishing and
these will be supported if there are valid environmental
reasons, but will be opposed if they are biased and
unjustified. It is concluded that spearfishing in Australia
is ecologically sustainable.

I think the only impact that a spearfisherman can have is picking off the bigger fish of the various targeted species as was discussed in an earlier forum. It is definitely sustainable and has very little impact on the ocean when compared to the commercial fishing industry. Take the commercial pursein vessels, they take hundreds of tons of sardines and anchovies... not to mention by-catch almost every night. The commercial trawlers literally drag their net along the bottom of the ocean... just image the habitat destruction and huge levels of by-catch. Longliners kill hundreds of thousands of birds, sharks and untargeted species annually. So is the fact that I shot a few galjoen, yellowtail and the odd tuna going to have such a significant impact? I'm definitely not losing sleep over it!

I agree 100% with you. The impact that commercial longliners and trawlers is devastating

I'm not sure if you are aware, but the Chinese have signed a deal with the Mozambiquan goverment, in which they will provide certain road infrastructure for free, if the Chinese obtain fishing rights to the Mozambique waters.

If Im not mistaken, this happened about 5 years ago. A friend of mine is a avid scuba diver, and went diving in Mozam in June. There crew did 21 dives on off-shore reefs, and did not see one tiger shark, one bull shark, or one of the bigger reef shark species... I think we can put two and two together

I watched "The Cove" last night, I took it out at the video store. Any environmentally conscious spearo should take a look at this. It is about the mass slaughter of dolphins in Taiji, Japan. Take a look on youtube... there will be some footage. It is truly horrific!

Its a huge eye-opener. Im on the mailing list, which updates you to what progress has been made. At the moment, the schools have been reissued with dolphin and whale meat