Mediterranean marine protected areas

A collection of five recent papers assesses the role and effectiveness of marine protected areas (MPAs) in the Mediterranean. The papers provide a broad perspective of MPAs and include social, economic, cultural, biological and statistical components.     

Marine protected areas in 'nonlinear' ecosystems

The very large changes observed within marine communities, owing to excessive harvesting, have been attributed to switches between alternative stable states. Correspondingly large reductions in overall fishing effort are usually difficult to implement. For such 'nonlinear' ecosystems, introducing large marine protected areas, with low to zero harvesting, but without reduction in overall fishing effort, can give a marked increase in total yield of the depleted stocks. These increases, however, are still less than can be achieved by reducing fishing effort.     

European protected areas go upmarket

A meeting of the IUCN, the World Conservation Union, and a subsidiary, the World Commission on Protected Areas (WCPA) Europe Members was held in Pörtschach am Wörther See, Carinthia, Austria from 12 to 15 June 2002.     

Viral dynamics in two trophically different areas in the Central Adriatic Sea

To understand the activity of marine viruses, experiments on viral production, viral decay and the percentage of lytic and lysogenic bacterial cells among the total number of bacterial cells were carried out seasonally at two stations in the Adriatic Sea with different trophic conditions. Additionally, we are providing an insight on the enrichment with dissolved and particulate organic matter by viral lysis in the studied area. Viral production was higher at the coastal station than at the open-sea station. Viral decay rates were also higher at the coastal sea station than at the open-sea station, and accounted for approximately 40% of viral production at both investigated stations. The percentage of lysogenic infection was lower than that of lytical infection, which indicates the prevalence of the lytic cycle at both stations. Viruses had a significant influence on bacterial mortality through high daily removal of the bacterial standing stock at the coastal and open-sea station. The viruses contributed to the restoration of dissolved organic carbon, nitrogen and phosphorus in the microbial loop by lysing the bacterial cells at the studied stations. All the above suggest that viruses are important in the microbial food web and an important factor in the control of bacterial populations within the study area.     

Effectiveness of protected areas in maintaining plant production

Given the central importance of protected area systems in local, regional and global conservation strategies, it is vital that there is a good understanding of their effectiveness in maintaining ecological functioning. Here, we provide, to our knowledge, the first such global analysis, focusing on plant production, a "supporting" ecosystem function necessary for multiple other ecosystem services. We use data on the normalized difference vegetation index (NDVI) as a measure of variation in plant production in the core, boundary and surroundings of more than 1000 large protected areas over a 25 year period. Forested protected areas were higher (or similar), and those non-forested were lower (or similar), in NDVI than their surrounding areas, and these differences have been sustained. The differences from surrounding areas have increased for evergreen broadleaf forests and barren grounds, decreased for grasslands, and remained similar for deciduous forests, woodlands, and shrublands, reflecting different pressures on those surroundings. These results are consistent with protected areas being effective both in the representation and maintenance of plant production. However, widespread overall increases in NDVI during the study period suggest that plant production within the core of non-forested protected areas has become higher than it was in the surroundings of those areas in 1982, highlighting that whilst the distinctiveness of protected areas from their surroundings has persisted the nature of that difference has changed.     

The management effectiveness of protected areas in Kenya

Merely designating new and/or expanding existing protected areas (PAs) does not guarantee the protection of critical ecosystems and species. The management of PAs must be effective to sustain meaningful conservational outcomes. We inferred the management effectiveness of PAs in Kenya based on the representation of ranges and distribution of multiple diversity dimensions of terrestrial mammals and their association with governance and designation types. We hypothesized that different governance types underlie variable management efficacies, such that stricter-managed PAs have better habitats that attract more wildlife, translating to higher species diversity compared to less strictly-managed PAs, especially for focal species groups (large carnivores, large herbivores, and endangered species). The results showed nearly all terrestrial mammals in Kenya represented in at least one PA. However, the relative proportion of represented ranges were low, and analysis of spatial conservation prioritization showed significant expansion beyond current PAs needed to achieve a one third coverage of focal species’ ranges in a best-solution reserve system. Differences in PA governance and designation types were not systematically associated with diversity variances, and while there were more unique species in state-managed PAs than in privately-managed ones, averaged diversity coefficients were comparable between categories. Diversity variances explained by PA size and status year were low in a combined species pool but increased in focal species groups. These findings suggest that success in terrestrial mammal conservation in PAs in Kenya require clearly and formally streamlined definition, performance feedback, and collaboration terms between state-managed and privately-managed PAs.

     

Evaluating the ecological performance of protected areas

While protected areas are a key component of the global conservation strategy, quantitative demonstrations of their positive ecological performance, meaning the extent to which they conserve the biodiversity features they were designated for, is broadly lacking. This commentary presents the emerging field of impact of evaluation of protected areas, with a focus on establishing their ecological performance. It highlights recent advances in protected area evaluations and explores the challenges remaining in developing a more credible evidence base to demonstrate the biodiversity conservation benefits of protected areas.     

The scientific value of Amazonian protected areas

Protected areas (PAs) are under increasing pressure to demonstrate their broader value and contribution to society. Scientific research and associated knowledge production comprise one such value, which has received relatively little attention in the academic literature. Here, we use the Amazon region as a case study to quantify scientific knowledge production (as measured by scientific publications in peer-reviewed journals) in PAs and identify the main biophysical, geographical and social characteristics that influence such production. We adopt a multi-model inference approach with an innovative hurdle regression model to independently assess the factors influencing the presence of research and the number of studies in PAs. Our results indicate a highly skewed pattern of scientific production, with many PAs with few or no associated scientific articles. Larger, older and more highly protected PAs in Ecuador and Peru were most likely to have scientific production, while time since first publication was most strongly associated with the number of publications from a PA. These findings provide important insights that could be used to support and strengthen policy aimed at increasing the value of Amazonian protected areas for scientific research.     

Key drivers of effectiveness in small marine protected areas

Marine Protected Areas (MPAs) are a key management tool for the conservation of biodiversity and restoration of marine communities. While large, well-designed and enforced MPAs have been found to be effective, results from small MPAs vary. The Hawkesbury Shelf, a coastal bioregion in New South Wales, Australia, has ten small, near-shore MPAs known as Aquatic Reserves with a variety of protection levels from full no-take to partial protection. This study assessed the effectiveness of these MPAs and analysed how MPA age, size, protection level, wave exposure, habitat complexity, and large canopy-forming algal cover affected fish, invertebrate and benthic communities. We found aspect, protection level, complexity and algal canopy to be important predictors of communities in these MPAs. Most MPAs, however, were not effective in meeting their goals. Only full no-take protection (three out of ten MPAs) had a significant impact on fish assemblages. One no-take MPA—Cabbage Tree Bay—which is naturally sheltered from wave action and benefits from an active local community providing informal enforcement, accounted for most of the increased richness of large fish and increased biomass of targeted fish species. Our findings suggest that small MPAs can enhance biodiversity and biomass on a local scale but only if they have full no-take protection, are in sheltered locations with complex habitat, and have positive community involvement to engender support and stewardship. These results provide a baseline for robust assessment of the effectiveness of small MPAs and inform future management decisions and small MPA design in other locations.     

Introduction to special issue on protected areas

Papers

Introduction to special issue on protected areas     

Conservation biology: beyond marine protected areas

Socioeconomic and ecological analyses of eleven coral reef conservation efforts make clear that marine protected areas are not the answer, and that in fact support of local communities is far more important than some government mandated 'fishing closure'. Apparently there are marine 'paper parks' just as there are terrestrial 'paper parks'.     

Size-dependent resistance of protected areas to land-use change

One of the major threats facing protected areas (PAs) is land-use change and habitat loss. We assessed the impact of land-use change on PAs. The majority of parks have been effective at protecting the ecosystems within their borders, even in areas with significant land-use pressures. More in particular, the capacity of PAs to slow down habitat degradation and to favour habitat restoration is clearly related to their size, with smaller areas that on average follow the dominant land-use change pattern into which they are embedded. Our results suggest that small parks are not going to be viable in the long term if they are considered as islands surrounded by a 'human-dominated ocean'. However, small PAs are, in many cases, the only option available, implying that we need to devote much more attention to the non-protected matrix in which PAs must survive.     

Ecological science and the management of protected areas

This paper aims to survey a few among many ecological principles that are particularly relevant to the management of protected areas. Various aspects of the relation between area of protected habitat and numbers of constituent species preserved are discussed, with emphasis of edge effects and other factors. Particular attention is given to those species which persist via local extinctions and recolonizations within a shifting mosaic of patches, and to the counter-intuitive things that can happen to such species or communities when a fraction of the patches is destroyed. The paper concludes with comments about making choices as to which areas to preserve — the calculus of biodiversity — and about more general social and economic considerations.     

Statutory protected areas and avian species richness in Britain

An effective portfolio of protected areas should, all else being equal, give rise to positive relationships between the amount of protected land in a region and the numbers of species present. Tests of this prediction are, however, extremely scarce, and most do not control for the potentially confounding effects of environmental factors that influence broad geographic trends in biodiversity. Here, we document the form of the relationship between species richness and coverage by protected areas using the British avifauna as a case study. We contrast relationships that arise for breeding and wintering assemblages, considering both all species collectively and threatened species only. We use spatially explicit multiple regression analyses that take into account environmental factors previously shown to exert a marked influence on avian species richness in Britain (temperature and altitude). Avian species richness and the amount of protected land are consistently positively correlated with each other, and the slopes of these relationships do not differ between assemblages (breeding/wintering and all species/threatened species). Explanatory power is, however, very weak which may be indicative of the ability of conservation measures in the wider landscape to maintain avian species richness, reducing any distinctive influence of protected areas. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Surprisingly high economic costs of biological invasions in protected areas

Biological Invasions - Biological invasions are one of the main threats to biodiversity within protected areas (PAs) worldwide. Meanwhile, the resilience of PAs to invasions remains largely...