Faculty Opinions recommendation of Larval dispersal connects fish populations in a network of marine protected areas.

Abstract Le Quesne, W. J. F., and Codling, E. A. 2009. Managing mobile species with MPAs: the effects of mobility, larval dispersal, and fishing mortality on closure size. – ICES Journal of Marine Science, 66: 122–131. The use of closed areas (marine protected areas, marine reserves, no-take zones) has been suggested as a possible solution to the perceived global fisheries crisis. However, to optimize the design and evaluate the effectiveness of closed areas, we need to understand the interaction between larval dispersal, adult mobility, and fishing mortality. In this paper, a simple, spatially explicit dynamic population model was developed to examine the effects of these interacting factors on optimal closure size and resulting yields. The effect of using one large or several smaller closed areas was also examined. Our model confirmed previous results: closed areas do not improve the yield of populations that are optimally managed or underexploited and, as mobility increases, optimum closure size increases. The model also predicted some interesting counter-intuitive results; for overexploited stocks, the greatest benefit from closed areas can be obtained for stocks with highest mobility, although this may require closure of 85% of the total area. For the tested parameter settings, adult spillover had greater potential to improve yield than larval export, and using several small closed areas rather than a single larger one had the same effect as increasing the mobility of the population.

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Modelling the impacts of marine protected areas for mobile exploited fish populations and their fisheries: what we recently learnt and where we should be going

Aquatic Living Resources ◽

10.1051/alr/2014013 ◽

2014 ◽

Vol 27 (3-4) ◽

pp. 107-133 ◽

Cited By ~ 10

Author(s):

Arnaud Grüss

Keyword(s):

Protected Areas ◽

Marine Protected Areas ◽

Fish Populations

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An MPA Design Approach to Benefit Fisheries: Maximising Larval Export and Minimising Redundancy

Diversity ◽

10.3390/d13110586 ◽

2021 ◽

Vol 13 (11) ◽

pp. 586

Author(s):

Colm Tong ◽

Karlo Hock ◽

Nils C. Krueck ◽

Vladimir Tyazhelnikov ◽

Peter J. Mumby

Keyword(s):

Protected Areas ◽

Marine Protected Areas ◽

Larval Dispersal ◽

Simple Approach ◽

Multiple Sources ◽

The Bahamas ◽

Dynamic Algorithm ◽

Larval Connectivity ◽

Strongly Connected ◽

The Caribbean

In the design of marine protected areas (MPAs), tailoring reserve placement to facilitate larval export beyond reserve boundaries may support fished populations and fisheries through recruitment subsidies. Intuitively, capturing such connectivity could be purely based on optimising larval dispersal metrics such as export strength. However, this can lead to inefficient or redundant larval connectivity, as the subset of sites with the best connectivity metrics might share many of the same connections, making them, collectively, poor MPA candidates to provide recruitment subsidies to unprotected sites. We propose a simple, dynamic algorithm for reserve placement optimisation designed to select MPAs sequentially, maximising larval export to the overall network, whilst accounting for redundancy in supply from multiple sources. When applied to four regions in the Caribbean, the algorithm consistently outperformed approaches that did not consider supply redundancy, leading to, on average, 20% greater fished biomass in a simulated model. Improvements were most apparent in dense, strongly connected systems such as the Bahamas. Here, MPA placement without redundancy considerations produced fishery benefits worse than random MPA design. Our findings highlight the importance of considering redundancy in MPA design, and offer a novel, simple approach to improving MPA design for achieving fishery objectives.

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THE SURVIVAL OF TRANSPLANTED CORAL ON PYRAMID-SHAPED FISH SHELTER ON THE COASTAL WATERS OF KELAPA AND HARAPAN ISLANDS, KEPULAUAN SERIBU, JAKARTA

Indonesian Aquaculture Journal ◽

10.15578/iaj.7.1.2012.79-85 ◽

2012 ◽

Vol 7 (1) ◽

pp. 79

Author(s):

Ofri Johan

Keyword(s):

Mortality Rate ◽

Protected Areas ◽

Marine Protected Areas ◽

Coastal Waters ◽

Coral Species ◽

Fish Population ◽

Fish Populations ◽

Live Coral ◽

One Year ◽

Base Of Pyramid

Research was carried out in August 2008 at two sites within Marine Protected Areas (MPA) in Kelapa and Harapan Islands of Seribu Islands, Indonesia. The purpose of this research was to compare the mortality rate of coral transplanted on the upper and base of pyramid-shaped concrete fish shelters. Fish shelters were placed on the seabed of Kelapa Island which is characterized by sandy seabed and Harapan Island which is characterized by silt. Both sites are within Marine Protected Areas. The survey recorded mortality rate of transplanted coral and percentage of live coral coverage. The research also sampled fish populations within the MPA sites and pyramid areas so that the two sites can be compared for their fish biodiversity. The data were analyzed by using T-Test Student of SPSS 11.5 computer program to compare between two locations, and upper and base of transplanted position. After one year, the average mortality rate among transplanted coral species in Kelapa Island was 34%. However, the mortality rate of transplanted coral in Harapan Island was slightly higher than in Kelapa Island: 42%. The transplanted coral at the top of the fish shelter had higher survival rate (39%) compared to the base of the fish shelter (24%). Fish populations in Kelapa Island consisted of 1,119 individuals from 35 species. This was much higher than in Harapan Island where the research found only 655 individuals from 27 species. Fish populations found around the fish shelter area in Kelapa Island consisted of 125 individuals from 25 species. This was lower than the fish population in Harapan Island, where 206 individuals from 23 species were recorded.

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