Quote:
Originally Posted by Stan K G
|
Very weak study. And I'm not the only one who thought so:
Science 15 February 2002:
Vol. 295. no. 5558, pp. 1233 - 1235
DOI: 10.1126/science.295.5558.1233b
Prev | Table of Contents | Next
Letters
Marine Reserves and Fisheries Management
In their report "Effects of marine reserves on adjacent fisheries" (30 Nov., p. 1920), C. M. Roberts and co-authors present data indicating that fishery yields have increased in waters adjacent to marine reserves in St. Lucia and east Florida.
In many developing island nations like St. Lucia in the Caribbean, fisheries are seriously overexploited, and little or no fisheries management exists.
In such cases where marine reserves are the primary means of control of fishing effort and catch, they can result in increased yields compared with a no-management scenario. However, the St. Lucia example is specific to coral reef fisheries and does not prove the global utility of reserves to fisheries.
In contrast to St. Lucia, the recreational fisheries in east Florida are stringently regulated. Currently, the bag limit for red drum is one fish per person, with a slot limit of 18 to 27 inches (~46 to 69 centimeters) long (1).
What effect have these regulations had on sizes of red and black drum along the entire east coast of Florida? According to the Marine Recreational Fisheries Statistics Survey, the mean weight of red drum and black drum in east Florida has more than doubled since the 1980s (2). Although the reserves in the Merritt Island National Wildlife Refuge examined by Roberts et al. reportedly have provided trophy-size fish to a limited area outside their boundaries,
"traditional" fisheries management has resulted in size increases across the entire fishery. Furthermore, it is estimated that 80 to 90% of reserves have not succeeded in meeting their management objectives, even in coral reef systems (3).
Before implementing new reserves, it would be wise to ask whether a reserve is the best strategy for managing a particular fishery, and how might current reserves be better managed so that they attain their fishery goals.
Mark H. Tupper
University of Guam Marine Laboratory,
UOG Station,
Mangilao, GU 96923, USA.
E-mail: mtupper{at}guam.uog.edu
References and Notes
1. Florida Fish and Wildlife Conservation Commission, Red Drum Management Plan (Specific Authority Art. IV, Sec. 9, Florida Constitution, chaps. 83-134, Laws of Florida, amended 1991).
2. Data were queried from the Marine Recreational Fisheries Statistics Survey available at
http://www.st.nmfs.gov/st1/recreatio...ies/index.html
3. G. Kelleher, C. Bleakley, S. Wells, A Global Representative System of Marine Protected Areas (World Bank, Washington, DC, 1995); J. Alder, Coastal Manage. 24, 97 (1996); T. McClanahan, Coral Reefs 18, 321 (1999).
The study by C. M. Roberts and colleagues seems little more than a promotional tool for proposed no fishing zones styled as marine reserves. The authors conclude that marine reserves off the southwest coast of St. Lucia and the east coast of Florida have enhanced adjacent fisheries, but such a conclusion is overreaching, given the data they present.
In the latter case, for example, Roberts et al. examined data from the two reserve zones in the Merritt Island National Wildlife Refuge at Cape Canaveral. They conducted seine samples and report that they found more and bigger fish inside the area than outside where fishing was allowed. The study is presented as if the research were current, but no true dates are given for the seining. In fact, the seine samples go back to 1987-89 (1), a period when the fished waters were subjected to wanton commercial gill netting at its peak. In 1995, a Florida constitutional amendment finally banned the gill nets. This reform accompanied numerous new limits on recreational fishing. As a consequence, fish stocks have skyrocketed in the same fished area, as demonstrated in young-fish research projects by the state. So, all that Roberts et al. have shown is that when commercial pressures are curtailed, fish stocks thrive.
The authors bolster their conclusions about the Cape Canaveral marine reserves by listing a number of recreational fishing records supposedly set because of big fish migrating out of the reserves. However, before being closed to the public,
the reserve waters (part of what was established as the Cape Kennedy security zone) were already known to harbor record specimens of certain species because of prime habitat. In addition, there was a spurt of records along Florida's east coast, largely as the result of line-class categories created by the International Game Fish Association, as well as $1000 awards paid by a line manufacturer.
Importantly, many records were set in areas far removed from the reserve areas, including Mosquito Lagoon waters that are separated by land from them.
The real cause of perceived problems in fisheries management is the commercial take-for-profit.
There is no justification for banning family-level angling, which is allowed in Yellowstone and Everglades national parks and other fragile areas. Good management does not require draconian prohibitions.
Karl Wickstrom*
Florida Sportsman Magazine,
2700 South Kanner Highway,
Stuart, FL 34994, USA.
E-mail: karl{at}floridasportsman.com
*Founder and Editor-in-Chief
References and notes
1. D. R. Johnson, N. A. Funicelli, J. A. Bohnsack, N. Am. J. Fish. Manage. 19, 436 (1999).
The conclusions by C. M. Roberts and colleagues that the effects of the Soufri`ere Marine Management Area (SMMA) extended beyond its boundaries and that commercial fish yields were increased because of the marine reserve are weak, for two reasons. First, there were no controls in the study and thus there can be no strong evidence for an effect of the experimental treatment. Second, the increase in abundance and catch outside the reserve was far too rapid to have been due to a buildup of a spawning population inside the reserve and export of eggs and larvae.
Regarding the second point, proponents of marine protected areas argue that spawning stock will build up inside reserves and eggs, larvae, and juveniles will then be exported to areas outside the reserves. For this chain of events to happen and for the exported eggs and larvae to grow to sufficient size for fishing would require time. Yet Roberts et al. report that the abundance outside the SMMA increased immediately after its establishment, despite the fact that fishing effort and catch increased outside the reserve. The rapid increase in abundance outside the SMMA could not have been due to increases in spawning stock inside. Alternative explanations for the data include an environmental change, as Roberts et al. suggest, or the effect of the experiment, which involved not only the establishment of the protected area, but "daily patrols by wardens," heightened public awareness, and other factors that could have contributed to improved compliance with existing regulations.
Ray Hilborn
School of Aquatic and Fishery Sciences,
University of Washington,
Seattle, WA 98195, USA.
E-mail: rayh{at}u.washington.edu
You seem to be a master of the ad hominem attack (e.g. people who might disagree with you are racist, islamaphobic, too stupid too understand the MLPA because they are economists), so I'm awaiting your slander. Perhaps the font I used is sexist?
