The effects of marine protected areas over time and species' dispersal
potential: a quantitative conservation conflict attempt

Abstract. Protected areas are an important conservation measure. However, there are controversial findings regarding whether closed areas are beneficial for species and habitat conservation as well as for harvesting. Species dispersal is acknowledged as a key factor for the design and impacts of protected areas. A series of agent-based models using random diffusion to model fish dispersal were run before and after habitat protection. All results were normalized without the protected habitat in each scenario to detect the relative difference after protecting an area, all else being equal. Model outputs were compared with published data regarding the impacts over time of MPAs on fish biomass. In addition, data on species' dispersal potential in terms of kilometres per year are compared with model outputs. Results show that fish landings of species with short dispersal rates will take longer to reach the levels from before the Marine Protected Areas (MPAs) were established than landings of species with long dispersal rates. Further, the establishment of an MPA generates a higher relative population source within the MPA for species with low dispersal abilities than for species with high dispersal abilities. Results derived here show that there exists a feasible win-win scenario that maximizes both fish biomass and fish catches.

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Higher fish biomass inside than outside marine protected areas despite typhoon impacts in a complex reefscape

Biological Conservation ◽

10.1016/j.biocon.2019.108354 ◽

2020 ◽

Vol 241 ◽

pp. 108354 ◽

Cited By ~ 4

Author(s):

Eva C. McClure ◽

Katherine T. Sievers ◽

Rene A. Abesamis ◽

Andrew S. Hoey ◽

Angel C. Alcala ◽

...

Keyword(s):

Protected Areas ◽

Marine Protected Areas ◽

Fish Biomass

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The impacts over time of marine protected areas: A null model

Ocean & Coastal Management ◽

10.1016/j.ocecoaman.2010.12.011 ◽

2011 ◽

Vol 54 (4) ◽

pp. 312-317 ◽

Cited By ~ 5

Author(s):

William Silvert ◽

Aristides Moustakas

Keyword(s):

Protected Areas ◽

Marine Protected Areas ◽

Null Model ◽

Over Time

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A modelling approach to assess the impact of land mining on marine biodiversity: Assessment in coastal catchments experiencing catastrophic events (SW Brazil)

10.31230/osf.io/ag3r6 ◽

2019 ◽

Author(s):

RAFAEL Almeida MAGRIS ◽

Martinho Marta-Almeida ◽

Jose Alberto Monteiro ◽

Natalie Ban

Keyword(s):

Protected Areas ◽

Marine Protected Areas ◽

Immediate Release ◽

Dam Failure ◽

Marine Biodiversity ◽

Pulse Disturbance ◽

Tailing Dam ◽

The Impact ◽

Over Time ◽

Modelling Approach

Analysis that link hydrological processes with oceanographic dispersion offer a promising approach for assessing impacts of land-based activities on marine ecosystems. However, such an analysis has not yet been customised to quantify specific pressures from mining activities on marine biodiversity including those from spillages resulting from tailing dam failure. Here, using a Brazilian catchment in which a tailing dam collapsed (Doce river) as a case study, we provide a modelling approach to assess the impacts on key ecosystems and marine protected areas subjected to two exposure regimes: (i) a pulse disturbance event for the period 2015-2016, following the immediate release of sediments after dam burst, which witnessed an average increase of 88% in sediment exports; and (ii) a press disturbance phase for the period 2017-2029, when impacts are sustained over time by sediments along the river’s course. We integrated four components into impact assessments: hydrological modelling, coastal-circulation modelling, ecosystem mapping, and biological sensitivities. The results showed that pulse disturbance causes sharp increases in the amount of sediments entering the coastal area, exposing key sensitive ecosystems to pollution (e.g. rhodolith beds), highlighting an urgent need for developing restoration strategies for these areas. The intensity of impacts will diminish over time but the total area of sensitive ecosystems at risk are predicted to be enlarged. We determined monitoring and restoration priorities by evaluating and comparing the extent to which sensitive ecosystems within marine protected areas were exposed to disturbances. The information obtained in this study will allow the optimization of recovery efforts in the marine area affected, and valuation of ecosystem services lost.

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Marine protected areas are more effective but less reliable in protecting fish biomass than fish diversity

Marine Pollution Bulletin ◽

10.1016/j.marpolbul.2019.04.015 ◽

2019 ◽

Vol 143 ◽

pp. 24-32 ◽

Cited By ~ 2

Author(s):

Jose A. Sanabria-Fernandez ◽

Josu G. Alday ◽

Natali Lazzari ◽

Rodrigo Riera ◽

Mikel A. Becerro

Keyword(s):

Protected Areas ◽

Marine Protected Areas ◽

Fish Diversity ◽

Fish Biomass

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Marine protected areas: Just for show?

10.31230/osf.io/hy4gq ◽

2018 ◽

Author(s):

RAFAEL Almeida MAGRIS ◽

Robert L. Pressey

Keyword(s):

Best Practices ◽

Protected Areas ◽

Marine Protected Areas ◽

Biological Diversity ◽

Conservation Strategy ◽

Convention On Biological Diversity ◽

The Core ◽

Historical Progress ◽

Spatial Dependencies ◽

Over Time

Several countries, including Brazil, are making compelling case for historical progress towards achieving the targets for marine protection under the Convention on Biological Diversity. However, this can be done through the establishment of large marine protected areas (MPAs) in the open ocean, a conservation strategy that might be only tangential to the core ecological goal of MPA designation, i.e. biodiversity conservation. By using two newly-designated large MPAs in Brazil as an example, we outline three ways in which they indicate poor adherence to best practices in MPA planning: placing no-take MPAs in areas with limited potential for extractive uses, neglecting the need to account for spatial dependencies among areas to maintain populations over time, and the inadequacy of the MPAs to regulate fishing of mobile pelagic species.

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Ecosystem-Based Management in Fiji: Successes and Challenges after Five Years of Implementation

Journal of Marine Biology ◽

10.1155/2011/940765 ◽

2011 ◽

Vol 2011 ◽

pp. 1-14 ◽

Cited By ~ 46

Author(s):

Stacy D. Jupiter ◽

Daniel P. Egli

Keyword(s):

Protected Areas ◽

Marine Protected Areas ◽

Fish Biomass ◽

Fishing Pressure ◽

Visual Census ◽

Underwater Visual Census ◽

Visual Distance ◽

Future Success ◽

Successes And Challenges

In 2005, a network of 3 large, district-wide marine protected areas (MPAs) and 17 village-managed closures (tabu) was established in Kubulau District, Fiji. Underwater visual census (UVC) data of fish biomass and benthic cover were collected between 2007 and 2009 and analysed with PERMANOVA and ANOSIM to assess differences between closed and open areas. High reef fish biomass (>1000 kg/ha) within closures, significantly elevated over open areas, was consistently observed from: (1) tabu areas on naturally productive reefs within visual distance from villages; and (2) the large, long-term permanent closure located away from fishing pressure. Factors that may have contributed to low fish biomass within closures include small size of closures; noncompliance with management rules; and disclosure of management success to fishers from villages with high reliance on fisheries products. Future success of the network depends on improving awareness of management rules and ensuring implementation within a broader ecosystem framework.

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Measuring the long-term success of small-scale marine protected areas in a Philippine reef fishery

Coral Reefs ◽

10.1007/s00338-020-01987-7 ◽

2020 ◽

Vol 39 (6) ◽

pp. 1591-1604

Author(s):

Daniel T. I. Bayley ◽

Andy Purvis ◽

Angelie C. Nellas ◽

Myrtle Arias ◽

Heather J. Koldewey

Keyword(s):

Protected Areas ◽

Marine Protected Areas ◽

Coral Cover ◽

The Philippines ◽

Anthropogenic Sources ◽

Small Scale ◽

Fish Biomass ◽

Trophic Groups ◽

Study Region

AbstractTropical coral reefs are subject to multiple pressures from both natural and anthropogenic sources. These pressures have caused widespread declines in reef health, resulting in the increased use of spatial management tools such as marine protected areas (MPAs). MPAs have proven generally effective if well designed and enforced, but there are limited long-term studies investigating how the presence of small-scale MPAs affects fish populations and reef communities. Using a 12-year time series, we found that small-scale (10–50 ha) community-managed MPAs along the Danajon Bank of the Philippines preserved average fish biomass within their boundaries over time relative to surrounding fished reefs. Unprotected areas are, however, showing significant long-term biomass decline. MPAs were also found to preserve more key trophic groups and larger-bodied commercially targeted reef fish families. Fish biomass of piscivore, scavenger and invertivore trophic groups inside individual MPAs is, however, still declining at a similar rate as outside. Surprisingly, long-term benthic cover and growth form composition were not significantly affected overall by MPA presence, despite the sporadic use of highly destructive dynamite fishing in this region. Coral cover has remained historically low (21–28%) throughout the study, following widespread bleaching mortality. While management tempered overall abundance declines, we found that irrespective of MPA presence, there was a generalised decline of both large- and small-bodied fish size groups across the study region, most steeply within the 20–30 cm length fish, and a shift towards proportionally higher abundances of small (5–10 cm) fish. This indicates a combination of over-exploitation, inadequate MPA size and coverage for larger fish, and the lingering effects of the 1998 bleaching event. Generalised shifts in body size and trophic structure reported here could lead to future reductions in fishery productivity and stability and will be further exacerbated unless broader fishery regulations and enforcement is instated.

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