[Coral-List] Pelagic MPAs
M.Johnson at hull.ac.uk
Mon Nov 1 20:05:26 EDT 2010
Every time I see MPAs justified on the basis of fisheries management I
cringe, (as I do when I see MSY as a target). Biodiversity yes, Fisheries
There are lots but I suggest Hilborn as an excellent source generally:
Hilborn et al (2004). When can marine reserves improve fisheries management?
Ocean & Coastal Management, 47:177-205
Hilborn (2006). Faith based fisheries. Fisheries 31(11):554-555
On 01/11/2010 20:37, "dfenner dfenner" <dfenner at blueskynet.as> wrote:
> In my message about pelagic MPAs such as Chagos, I ended asking if
> these issues had been considered in planning for large pelagic MPAs, and
> inviting their authors to educate us. I thank my colleagues for beginning
> the process of educating me on this. Indeed for the Chagos MPA there is
> quite a bit of information to support the role of pelagic MPA¹s. I list
> several references at the end of this message that give a great deal of
> information on the topic. In particular, the article by Sibert and Hampton
> say the median lifetime displacement of skipjack ranges from 420 to 470
> nautical miles. The lifetime displacement of yellowfin is about 20%
> less². Also
> The term, highly migratory¹ appears to have no operational definition in
> relation to the natural history of tunas. Rather, it is a legal term defined
> only in the context of the Law of the Sea.² Further: . . .the results also
> suggest that Pacific Island countries can implement effective domestic
> management policies to promote conservation and sustainable utilization of
> tuna stocks within their EEZs². They present a map of the western Pacific
> from the Philippines to American Samoa that shows that most of that area is
> within the EEZ¹s of various countries there (a map of the whole Pacific
> would show that a majority of the Pacific is not in any EEZ). They report
> that only 20% of the tuna catch in the western and central Pacific Ocean is
> taken outside of EEZ¹s. Thus, the EEZ¹s could be a very effective tool for
> managing stocks of those two species in that area, and could be for the
> Pacific in general. The new Chagos reserve is about 450 nautical miles in
> diameter, so it should have at least some effect on pelagic stocks within
> it. On the other hand, Sibert and Hampton also say ³The biological
> characteristics of tropical skipjack and yellowfin tunas estimated in this
> study are such that their movements will carry a significant proportion of
> the population beyond most EEZs during their lifetime. Some degree of
> cooperation between neighboring states would, therefore, appear to be
> essential for conservation and optimal exploitation of skipjack and
> yellowfin stocks.² Clearly, such international cooperation in the Pacific
> could be between nations with adjacent EEZ¹s, and would not require the
> agreement of all nations in the regional tuna councils or the distant water
> fishing nations. They argue that both local management within a country¹s
> EEZ and international management are needed. The Koldewey et al. (2010)
> paper lists several studies that have documented the positive effects of
> MPAs on migratory species. The Koldewey paper has far too much information
> in it to summarize succinctly and I highly recommend that it be read.
> I note that if a pelagic MPA is large enough to cover much of the
> range of a migratory species, but can¹t cover it all, the situation appears
> to be quite parallel to a small MPA on a coral reef, where fish moving
> outside the MPA are called ³spillover² and can increase fish catches in
> areas around the MPAs. In terms of fisheries, MPA¹s could be considered as
> natural fish farms, though their ecosystem protection benefits are much
> broader than that.
> I do not have similar information on the migratory range of other
> pelagic species such as Bigeye and albacore tuna, or sharks, swordfish,
> marlin, wahoo, etc. Based on the two we do have data on, the precautionary
> approach would be to assume they have similar sorts of ranges. The Koldewey
> paper indicates a third tuna species has a similar range, indicating that is
> probably a good assumption.
> My colleague rightly reminds me that these large pelagic MPAs often
> have many seamounts in them. Seamounts often concentrate some types of sea
> life, including tuna (as pointed out in the Koldewey paper). Further,
> trawling on seamounts which can catch huge quantities of long-lived fish
> such as orange roughy, effectively mining them much faster than they can
> reproduce, also is highly destructive to benthic communities such as deep
> coral beds.
> The Sibert & Hampton paper, and the Koldewey et al paper do not
> consider the problems of enforcement in detail. Koldewey et al. say
> that ³although
> some of the challenges relating to their implementation may be both costly
> and difficult (Kaplan et al., 2010).² The Game et al (2009) paper does
> consider the enforcement problem, but I have not yet been able to access
> this paper. As I pointed out in my previous message, VMS (vessel monitoring
> systems, a GPS and satellite system for remotely tracking ship movements) is
> widespread in tuna fleets, though I don¹t know how widely it is required.
> a system is very feasible (it would be too costly for small artisinal boats
> but a minor cost for industrial tuna ships, which are probably the main
> concern for remote pelagic MPAs). If tuna fishing boats are excluded from
> these MPAs, it would be relatively easy to track them continuously if they
> have VMS on them. A patrol boat could then intercept any found within the
> MPA. This won¹t stop boats that do not have VMS and poachers certainly
> wouldn¹t have VMS (illegal fishing is a problem everywhere). Compliance is
> always the goal of enforcement, and simply having the capability to catch
> violators and an occasional apprehension of one and punishment can produce
> good compliance, which in turn greatly reduces the logistics and costs of
> enforcement, as well as achieving the objectives. So perhaps it may not be
> as difficult as I imagined.
> The views I expressed in my previous message were taken virtually
> verbatim from meetings of the Scientific and Statistical Committee of the
> Western Regional Fisheries Management Council in Honolulu, in 2004 and early
> 2005. I note that the Sibert and Hampton article which reported that
> Skipjack and Yellowfin tuna have median lifetime migrations of only about
> 420-470 km, was published in 2003. Sibert was a member of that committee
> and I remember him present at most of the meetings I attended, though
> perhaps not at the particular meeting where that was discussed. Yet, no
> opinions contrary to the ones I heard and put in my message were expressed
> then. Bit surprising. Doug
> The Koleway and Sibert articles are available free online, just search for
> them on Google Scholar.
> Game, E.T., Grantham, H.S., Hobday, A.J., Pressey, R.L., Lombard, A.T.,
> Beckley, L.E.,
> Gjerde, K., Bustamante, R., Possingham, H.P., Richardson, A.J., 2009.
> protected areas: the missing dimension in ocean conservation. Trends Ecol..
> Evol. 24 (7), 360369.
> Koldewey, H., Curnick, D., Harding, S., Harrison, L., Gollock, M., 2010.
> benefits to fisheries and biodiversity of the Chagos Archipelago/British
> Ocean Territory as a no-take marine reserve. Marine Pollution Bulletin 60,
> Sheppard, C. 2010. Marine protected areas and pelagic fishing: The case of
> the Chagos Archipelago. Marine Pollution Bulletin 60: 1899-1901.
> Sibert, J., Hampton, J., 2003. Mobility of tropical tunas and the
> implications for
> fisheries management. Mar. Policy 27, 8795.
> Coral-List mailing list
> Coral-List at coral.aoml.noaa.gov
Dr Magnus Johnson
Centre for Environmental and Marine Sciences
University of Hull
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