Friday, March 9, 2012

Fisheries management in New Zealand: Maybe not as sustainable as you thought!

New Zealand's Ministry of Fisheries says that "New Zealand seafood comes from one of the best fisheries management systems in the world."  This claim warrants further investigation for what other countries might learn from both its successes and its challenges or issues.  Just because it might be one of the best systems currently in place does not mean it is 100% successful.  The written goals of fisheries management need to be compared with the actual health of ecosystems.  This can be done through scientific studies of course, but a basic assessment can also be done through direct observation.  One day snorkeling at the Goat Island Marine Reserve compared to the next day at Matheson’s Bay next door, outside of the reserve, showed very obvious impacts of fishing activity.   Additionally, the Poor Knights Island Marine Reserve is much larger (1890 ha) and farther offshore than the relatively small Goat Island Marine Reserve (547 ha), so the effectiveness of each of these reserves can be compared as well.

New Zealand’s marine area covers 14 times its land area.  The climate of New Zealand ranges from sub-tropical to sub-Antarctic, and the marine area includes a diverse range of ecosystems (source and source).  One estimate suggests that New Zealand’s marine area could contain up to 10% of the world’s marine biodiversity (source).  Eighty percent of the country’s native biodiversity is estimated to inhabit the marine area (source), and 44% is endemic to New Zealand (source).  Coastal protection is also crucial to New Zealand’s seabird species, which make up 37% of the country’s bird species, compared to only 3.9% of global bird species (lecture, Ria Brejaart).  The marine area supports a $1.5 billion fishing industry and $20 billion tourism industry (Forest and Bird).  Clearly, New Zealand’s vast ocean areas contain substantial biodiversity, which has historically faced and continues to face a range of human-related threats, including sedimentation, contamination, coastal development, invasion by exotic species, marine farming, boating activity, overexploitation, presence of swimmers, and physical damage from boats. 

New Zealand has a range of legislation pertaining to marine areas, including the Wildlife Act of 1953, the Marine Reserves Act of 1971, the Reserves Act of 1977, the Marine Mammals Protection Act of 1978, the Resource Management Act of 1991, the Fisheries Act of 1996, and the proposed Oceans Policy Initiative 2000.  Marine management in New Zealand involves a variety of participants with different and sometimes overlapping jurisdictions and responsibilities, and sometimes conflicting interests.  These include the Department of Conservation (DOC), the Ministry of Fisheries (now part of the Ministry of Agriculture and Forestry), Biosecurity New Zealand, the Ministry of Energy, Regional Councils, Territorial Authorities, and Iwi.  The Quota Management System was set up in 1986 to govern ‘sustainable utilisation’ of fisheries resources.  Basically, commercial fishers purchase transferable quota allowances, which are proportions of the Total Allowable Take set for each species, which is supposed to be based on stock assessments.  Oftentimes the people fishing are not the ones who own the quota, because quotas can be leased.  The TAC is divided into commercial take, recreational take, and customary take.  In the 1960s, government deregulation of the fisheries industry led to great declines in fish stocks.  Since that time, policy efforts have been made to manage fishing in order to sustain stocks.  The stated purpose of the Fisheries Act is “to provide for the utilisation of fisheries resources while ensuring sustainability” (source).  Ensuring sustainability is defined as: “(a) Maintaining the potential of fisheries resources to meet the reasonably foreseeable needs of future generations; and (b) avoiding, remedying, or mitigating any adverse effects of fishing on the aquatic environment.”  Utilisation is defined as “conserving, using, enhancing, and developing fisheries resources to enable people to provide for their social, economic, and cultural well-being.”  The Act also states the following environmental principles:  “(a) associated or dependent species should be maintained above a level that ensures their long-term viability; (b) biological diversity of the aquatic environment should be maintained; (c) habitat of particular significance for fisheries management should be protected.”  However, the wording regarding these principles is relatively weak: this section “requires that all actions under this Act include consideration of the following environmental principles” (emphasis added).  These environmental principles suggest a level of awareness of the need for more of an ecosystem-based approach to management in order to maintain the economically important species.

A 2010 Ministry of Fisheries summary showed that Total Allowable Commercial Take was 599,126 tonnes, and actual commercial take was 409,449 tonnes.  Recreational fisheries estimated annual take: 25,000 tonnes, and Maori customary take provided for within the TAC was 4,813 tonnes (source).  The New Zealand Biodiversity Strategy (NZBS) of 2000 states that: “Since the introduction of the fisheries Quota Management System (QMS), most QMS stocks for which biomass and productivity data are known are thought to be above sustainable levels.  However, for over half of the stocks managed under the QMS, too little is known to be able to assess whether harvesting levels are sustainable” (source).  Basically, the quota system manages fishing catch, but for lack of information or for decisions influenced by factors other than science, many of these allowable take levels are likely too high to really ensure sustainable fish stocks.  Additionally, the scientific concept that these catch limits are based on is called Maximum Sustainable Yield (MSY).  This is a very dangerous idea in practice, because if the stock assessment overestimates the abundance of a particular fish species, the MSY level would be set too high, leading to overexploitation and potentially rapid depletion.

Twenty-one species of native/endemic fish were listed as vulnerable on FishBase.org.  “Only in the California Current and in New Zealand are current exploitation rates predicted to achieve a conservation target of less than 10% of stocks collapsed” (source).  Of the 97 species involved in the Quota Management System, 67.5% of stocks appear to be at or near their target levels (source).  However, if these target levels are set too low, even though 2/3 of stocks are meeting targets, they might still not be in a healthy state.  An assessment of 78 commercial fisheries in New Zealand by Fish and Bird found the following results:
·         42% are overfished, or have substantially declined
·         69% cause habitat damage
·         71% cause adverse ecological effects
·         Only 15% have had all stocks assessed in the last 5 years
·         35% were missing basic biological information
A September 2009 “Environmental Snapshot” on fishing activity by the Ministry for the Environment found that commercial fish catch has been declining recently, both due to management efforts and to declining abundance of some fish stocks.  In 2008 29% (of 101 known fish stocks) were overfished.  This represents a doubling of 2006 rates of overfishing (source).






The NZBS had several ambitious goals for the protection of marine biodiversity, including protection of 10% of the country’s marine environment in a network of Marine Protected Areas by 2010.  This has not been met.  Currently, 7% of New Zealand’s territorial sea is protected by marine reserves.  In reserves, there can be no commercial fishing, traditional fishing, recreational or sport fishing, no construction, dumping, or dredging.  No-take marine reserves protect all species, known and unknown, and ecosystem processes.  Additionally, there are several other types of marine protection that allow certain levels of activities such as Marine Protected Areas, where regulated fishing can occur.  Seven percent is a relatively large number compared to other countries, especially given the disproportionally large amount of sea compared to land area.  However, less than 3% of this reserve area is in ‘mainland’ marine reserves (compared to offshore reserves).  The near-shore area tends to be affected primarily by recreational fishing activity, while offshore is where the bulk of commercial fishing takes place. 

In comparison to this very small area of coastal marine reserves, 33.4% of the land area is “legally protected for the primary purpose of protecting biodiversity” (source).  “The total marine area protected by mainland marine reservesis equivalent to around one-and-a-half times the area of New Zealand’s smallest national park on land (Abel Tasman National Park)” (source).  Four of the coastal biogeographic regions lack marine reserves entirely, and the protection at all of these regions except the Fjordlands is under 1% of the regional area (see figure below).  Bill Ballantine, one of the original spearheaders of the establishment of the marine reserve at Leigh, proposes the following guidelines for effective marine reserve protection: representativeness of all ecosystems and regions, replication (at least three of each type of ecosystem), network arrangement (connectivity), and a sustainable size.  He also argues that for science and education, 10% of marine area should be protected under marine reserve status; to ensure conservation, this rises to 20%; to additionally maximize benefits to fisheries, reserves should cover 30% (source).  Also, the primary purpose of marine reserves according to the Marine Reserves Act of 1971 is for scientific research.  Reserves provide great opportunities for comparative studies, but there are also some issues with research.  For example, when we were at the University of Auckland campus at Leigh, one of the graduate students described how she has had great difficulties getting permits to take samples for her research due to issues with the Department of Conservation.
 (source)



Overfishing of one fish species obviously has implications for that species, but it also might have implications for the larger ecosystem.  For example, at Leigh and Matheson’s Bay, we observed the cascade effects of overfishing of snapper and crayfish.  These are two very important predators of kina (sea urchins), and so their decline removes the pressure on kina populations, leading to greater kina consumption of seaweed.  Kina barrens result in areas of snapper and crayfish overexploitation.  The Goat’s Island Marine Reserve was established in 1975.  In 1977, about 30% of the subtidal rocky reefs were dominated by sea urchin grazing.  By 1997, this figure was down to 3% (source).  Snapper and lobster populations have been allowed to replenish, leading to regeneration of seaweed.  A 2011 survey found higher fish species diversity within the reserve compared to outside of the reserve, and more abundant populations of snapper, butterfish, john dory, banded wrasse, blue cod, and other species (source).  

 Kina Barren.  (source)



Snapper and kelp, Goats Island Marine Reserve (source)

In our February 2012 survey of snapper in both the Goat Island Marine Reserve and the nearby non-reserve Matheson’s Bay, a popular recreational fishing site, we found a much more abundant stock of snapper within the marine reserve area.  Additionally, the visibility at Matheson’s was extremely low, with lots of suspended sediment, not very conducive to fish and plant life.  These two very close habitats show the potentially huge impact of recreational fishing on close to shore marine areas.  This example (and there are probably many examples like this in New Zealand) suggests that the current policies on fish catch are insufficient to protect fish stocks, which has negative implications not just for the habitats and ecosystems, but also for the fisheries themselves.  The Fisheries Act is supposed to protect sustained stocks of fish for utilization.  Fishing boats have been known to sit on the reserve boundary at Goat Island to take advantage of the more abundant and larger fish coming supplied by the reserve.  This is evidence that marine reserves could be in the best interests of fishers, not just for environmental motivations.

Snapper count from transect surveys at Goat Island Marine Reserve (solid) and at Matheson's Bay (striped) over kelp and rock/sand habitats.  Data collected February 2012 by EcoQuest.

In addition to comparing areas within marine reserves to areas outside of reserve protection, it is also interesting to compare different marine reserves.  Goat Island was established as a marine reserve in 1975, and includes the waters 800m from shore for a 5km stretch of coast.  The Poor Knights Islands are 24km off the east coast of the Northland region and contain even more unique habitat and organisms due to the East Auckland Current which brings warmer water and tropical larvae to New Zealand’s more temperate waters. The cliffs and archways provide habitat variation and protection.  A marine reserve was established in 1981 with the goal of protecting reef fish that are vulnerable to overfishing, long-lived, and/or have low rates of reproduction.  Essentially this was more of a marine park than a fully effective reserve until 1998, when it was given full no-take marine reserve status.  From 1981 to 1998, all commercial fishing but only some recreational fishing was prohibited.  In 1998, DOC was reviewing whether recreational fishing had a substantial impact on the ecosystem, and it was decided that there was insufficient information to decide this in the favor of continuing recreational fishing (source).  So the equivalent protection status was granted to the Poor Knights 23 years later than Goat Island.  Already, abundance and size of targeted fish species have been observed to be on the rise in the Poor Knights Islands Marine Reserve.  The snapper in particular has benefited from the reserve status.  The incomplete protection from fishing for 17 years may have had the inadvertent effect of leading to an increase in recreational fishing due to an image of the marine park having larger and more abundant fish.  Therefore the full protection was critical in effectively protecting the area.

Another comparison between Goat Island and the Poor Knights is the difference in size of the marine reserve.  Goat Island is a very small area, and although we can see the positive effects that the protection has had, it likely is more affected by outside activities and edge effects from non-protected areas.



Although Poor Knights Islands received full protection later than Goat Island, the fish stocks, habitat, and ecosystems there might recover more quickly and more fully in some ways than Goat Island due to this size impact.

New Zealand has a lot of positive sounding legislation and goals to protect the marine area.  However, these are primarily geared toward protection for sustenance of the fisheries industry, rather than protection for the sake of biodiversity, in contrast to the abundance of biodiversity-focused protection efforts on land.  The rising rate of overfishing is troubling, and changes to fisheries policy and implementation need to happen soon if this trend is to be slowed and reversed.  Stock assessments need to be more effectively, thoroughly, and frequently performed, and quotas need to be established cautiously.  Yield levels close to the MSY can be attained both by leaving approximately 20% of virgin biomass and by leaving approximately 40%.  The latter should be tested to see if 40% can become the new target.  Leaving more fish in an ecosystem would likely benefit the species, the larger ecosystem, and the sustainability of fisheries.  Full no-take marine reserves also should be expanded to protect biodiversity and unique habitats, as well as to benefit fishing in surrounding areas.  In 2009, the Cabinet supported the Fisheries 2030 strategy, with the following goal: “to have New Zealanders maximizing benefits from the use of fisheries within environmental limits” (source).  The strategy is aimed at improving the fisheries industry on economic and environmental criteria.  It appears that overall the current management of fishing in New Zealand has been insufficient to meet the country’s goals both for environmental protection but also for sustainability of the fishing industry.  If policy can take a more conservative approach, even slight reductions in catch limits could have a big impact on replenishing fish stocks, and ecosystems as well as fishers will benefit.

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