Comment
Unleashing the wild: response to Locke and Dearden's ‘rethinking protected area categories’
- DIEGO MARTINO
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- Published online by Cambridge University Press:
- 24 November 2005, pp. 195-196
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Locke and Dearden (2005) assert that the emerging new paradigm for protected areas (PAs) risks taking the PA agenda to a ‘tragic failure,’ and the planet towards biological impoverishment. They believe the ‘new paradigm’ contributes to a persistent tendency towards giving social issues higher priority over biological considerations and is based on the promotion of PA categories V and VI of the IUCN (World Conservation Union).
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Rethinking protected area categories and the new paradigm
- HARVEY LOCKE, PHILIP DEARDEN
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- Published online by Cambridge University Press:
- 25 April 2005, pp. 1-10
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The World Conservation Union (IUCN) plays a global leadership role in defining different types of protected areas, and influencing how protected area systems develop and are managed. Following the 1992 World Parks Congress, a new system of categorizing protected areas was developed. New categories were introduced, including categories that allowed resource extraction. Since that time there has been rapid growth in the global numbers and size of protected areas, with most growth being shown in the new categories. Further-more, the IUCN has heralded a ‘new paradigm’ of protected areas, which became the main focus of the 2003 World Parks Congress. The paradigm focuses on benefits to local people to alleviate poverty, re-engineering protected areas professionals, and an emphasis on the interaction between humans and nature through a focus on the new IUCN protected area categories.The purpose of this paper is to examine critically the implications of the new categories and paradigm shift in light of the main purpose of protected areas, to protect wild biodiversity. Wild biodiversity will not be well served by adoption of this new paradigm, which will devalue conservation biology, undermine the creation of more strictly protected reserves, inflate the amount of area in reserves and place people at the centre of the protected area agenda at the expense of wild biodiversity. Only IUCN categories I–IV should be recognized as protected areas. The new categories, namely culturally modified landscapes (V) and managed resource areas (VI), should be reclassified as sustainable development areas. To do so would better serve both the protection of wild biodiversity and those seeking to meet human needs on humanized landscapes where sustainable development is practised.
Comment
Economic valuation of non-marketed wild edible plants in Thailand
- CLAUDIO O. DELANG
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- Published online by Cambridge University Press:
- 19 May 2006, pp. 285-287
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Tropical forests can provide forest dwellers with a sizable proportion of their dietary needs. Yet, many development and conservation organizations tend to disregard these opportunities, promoting market-oriented reforms that aim at introducing cash crops and markets for non- timber forest products (NTFPs) in the name of poverty alleviation and/or biodiversity conservation. In so doing, they help relegate wild food plants to the position of food for the poor (De Beer & McDermott 1996; Neumann & Hirsch 2000), reserve food in case of famine (Takasaki et al. 2004), or food supplementing that produced on farm plots (Ousseynou & Tieguhong 2004). This comment discusses the economic rationale for the consumption of wild edible plants by forest-dwelling communities, comparing the results obtained from two methods of evaluation. The paper is based on one month of fieldwork during December 2004 carried out by the author together with Theresa Wong and two specially-trained research assistants in Thung Yai Naresuan Wildlife Sanctuary (Western Thailand).
The introduction of artificial structures on marine soft- and hard-bottoms: ecological implications of epibiota
- FABIO BULLERI
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- 12 August 2005, pp. 101-102
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Artificial structures, such as seawalls, breakwaters, jetties, pontoons and pier pilings are becoming ubiquitous features of landscape in shallow coastal waters of urbanized areas. Nonetheless, few published studies have focused on their ecology and little effort has been devoted to determine how the various objectives (economic, social and ecological) involved in their introduction into natural systems can be reconciled.
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Preferences for environmental issues among environmentally-concerned citizens in six countries
- KNUT LEHRE SEIP, MIGUEL ALVAREZ COBELAS, SYLVAIN DOLEDEC, JINGHUA FANG, VAL H. SMITH, OLGA S. VORONTSOVA
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- 16 March 2006, pp. 288-293
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Implementation of measures to protect and improve the environment requires knowledge about people's preferences, both to ensure economic means and to gain public support for the measures. Since environmental legislation and protection measures become increasingly cross-national, knowledge of benefit perception among people across countries is important. This study addresses the aggregated preferences of environmentally-concerned individuals in France, USA, Norway, Russia, China and Spain. The aggregated preferences in all groups showed emphasis on pollution issues (rank 1 out of six issues in all six countries). The groups were least concerned with animal rights, which here included the right for top predators like tigers and wolf to roam the wilderness in a way that may cause statistical fatalities (rank 4–6). The group's concern for pollution decreased with the buying power of the country to which they belonged (r2 = 0.967). Also, agreement among the individuals in the groups tended to be less when the buying power was large (r2 = 0.940). The study shows that benefits accrued in one country may not have the same weight in another country, in particular if countries have different economic development status. It also suggests that efforts to preserve species diversity may require other types of public motivation than efforts to reduce pollution or to use non-renewable resources.
Exercise-based transportation reduces oil dependence, carbon emissions and obesity
- PAUL A.T. HIGGINS
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- Published online by Cambridge University Press:
- 01 December 2005, pp. 197-202
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Societal dependence on oil leads to increasingly negative social consequences throughout the world, including climate change, air pollution, political and economic instability, and habitat degradation. Reliance on the automobile for transportation also contributes to a sedentary lifestyle, an obesity epidemic and poor health. These problems are particularly pronounced in the USA, which currently consumes c. 27% of global oil production and produces c. 25% of global carbon emissions, and where c. 65% of adults are overweight or obese. Other countries throughout the world that replicate or hope to replicate the automobile-based lifestyle of the USA face similar problems now or in the near future. This paper develops and applies calculations relating the distances that could be travelled through recommended daily walking or cycling with weight loss, oil consumption and carbon emissions. These straightforward calculations demonstrate that widespread substitution of driving with distances travelled during recommended daily exercise could reduce the USA's oil consumption by up to 38%. This saving far exceeds the amount of oil recoverable from the Arctic National Wildlife Refuge, suggesting that exercise can reduce foreign oil dependence and provide an alternative to oil extraction from environmentally sensitive habitat. At the same time, an average individual who substitutes this amount of exercise for transportation would burn respectively c. 12.2 and 26.0 kg of fat per year for walking and cycling. This is sufficient to eliminate obese and overweight conditions in a few years without dangerous or draconian diet plans. Furthermore, a reduction in carbon dioxide emissions of c. 35% is possible if the revenue saved through decreased health care spending on obesity is redirected toward carbon abatement. As a result, exercise-based transportation may constitute a favourable alternative to the energy and diet plans that are currently being implemented in the USA and may offer better development choices for developing countries.
Island-specific preferences of tourists for environmental features: implications of climate change for tourism-dependent states
- MARIA C. UYARRA, ISABELLE M. CÔTÉ, JENNIFER A. GILL, ROB R.T. TINCH, DAVID VINER, ANDREW R. WATKINSON
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- 25 April 2005, pp. 11-19
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Climate change may affect important environmental components of holiday destinations, which might have repercussions for tourism-dependent economies. This study documents the importance of environmental attributes in determining the choice and holiday enjoyment of tourists visiting Bonaire and Barbados, two Caribbean islands with markedly different tourism markets and infrastructure. Three hundred and sixteen and 338 participants from Bonaire and Barbados, respectively, completed standardized questionnaires. Warm temperatures, clear waters and low health risks were the most important environmental features determining holiday destination choice. However, tourists in Bonaire thereafter prioritized marine wildlife attributes (i.e. coral and fish diversity and abundance) over other environmental features, whereas tourists in Barbados exhibited stronger preferences for terrestrial features, particularly beach characteristics. The willingness of tourists to revisit these islands was strongly linked to the state of the preferred environmental attributes. More than 80% of tourists in Bonaire and Barbados would be unwilling to return for the same holiday price in the event, respectively, of coral bleaching as a result of elevated sea surface temperatures and reduced beach area as a result of sea level rise. Climate change might have a significant impact on Caribbean tourism economy through alteration of environmental features important to destination selection. Island-specific management strategies, such as focusing resources on the protection of key marine or terrestrial features, may provide a means of reducing the environmental and economic impacts of climate change.
A palaeoenvironmental reconstruction to aid in the restoration of floodplain and wetland habitat on an upper deltaic plain, California, USA
- K.J. BROWN, G.B. PASTERNACK
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- Published online by Cambridge University Press:
- 12 August 2005, pp. 103-116
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While tens of millions of dollars have been spent on land acquisition and planning for current and future floodplain and wetland restoration in the Sacramento-San Joaquin Delta, knowledge of the historical processes and landscape heterogeneity that are helpful in guiding the environmental restoration are often scarce. This study used palaeoenvironmental reconstruction to increase the historical perspective, with the aim of improving environmental management. Twelve sediment cores collected from the McCormack-Williamson Tract (MWT) leveed farmland and the juxtaposed Delta Meadows (DM) tidal wetland were sampled for a suite of environmental proxies. MWT was a non-tidal flood plain during much of the late-Holocene, with a mosaic of other habitats including dry uplands, riparian forests, and freshwater wetlands persisting nearby. Comparison with the regional sea-level history suggests that the upper delta gradually came under tidal influence 3000–800 calendar years before present (cal BP). Despite this, floodplain landforms and habitats prevailed at DM from 3650–330 cal BP, after which wetlands expanded, suggesting that a flood-based disturbance regime typified the upper delta for most of the late-Holocene. Recently, the upper deltaic plain has been profoundly disturbed by agriculture and other activities, rendering significant loss of habitat. It is believed that a flood-based disturbance regime will recur at MWT if the levees surrounding the tract are intentionally breached as planned for restoration, culminating in a variety of habitats similar to pre-agricultural conditions. Concentrations of Hg, Pb, As, and P pollutants elevated several-fold in surficial sediments are of particular concern, potentially becoming problematic after restoration.
Applying the ecological footprint to ecotourism scenarios
- COLIN HUNTER, JON SHAW
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- 16 March 2006, pp. 294-304
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Academic interest in ecotourism has grown rapidly in recent years, fuelled by the increasing popularity of ecotourism holidays. This paper adopts ecological footprint (EF) analysis as a means of estimating the potential net EF of hypothetical international ecotourism scenarios involving air travel. A procedure for the rapid calculation of indicative, potential minimum net EF estimates using secondary data sources was applied to a variety of source/host country scenarios with the aim of establishing a reasonable and conservative range of EF values associated with ecotourism. The influence of changing assumptions about the broad nature of resource demand at the destination and of three length of stay periods was considered. In total, 252 estimates were made of the potential net per tourist EF, assuming conservative resource use at the destination. For a 14-day holiday, potential net EF estimates ranged between 0.02 and 4.26 global hectares. Only one, a 21-day scenario, produced a net negative EF value, suggesting the potential for an overall reduction in absolute demand on global renewable resources. Some 80% of 14-day holiday scenarios produced potential per tourist EF estimates greater than the annual average per caput EF in low income countries. The size of the transit component was very important to overall net EF estimates, supporting largely anecdotal concerns about the environmental impact of long-haul flights to ecotourism destinations. The implications of these findings for judging the impact of ecotourism were found to vary according to different absolute and relative benchmarks, although the global EF of ecotourism is likely to be considerably less than that of mass tourism.
An evaluation of mapped species distribution models used for conservation planning
- CHRIS J. JOHNSON, MICHAEL P. GILLINGHAM
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- 12 August 2005, pp. 117-128
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The widespread use of spatial planning tools in conjunction with increases in the availability of geographic information systems and associated data has led to the rapid growth in the exploration and application of species distribution models. Conservation professionals can choose from a considerable number of modelling techniques, but there has been relatively little evaluation of predictive performance, data requirements, or type of inference of these models. Empirical data for woodland caribou Rangifer tarandus caribou was used to examine four species distribution models, namely a qualitative habitat suitability index and quantitative resource selection function, Mahalanobis distance and ecological niche models. Models for three sets of independent variables were developed and then a temporally independent set of caribou locations evaluated predictive performance. The similarity of species distribution maps among the four modelling approaches was also quantified. All of the quantitative species distribution models were good predictors of the validation data set, but the spatial distribution of mapped habitats differed considerably among models. These results suggest that choice of model and variable set could influence the identification of areas for conservation emphasis. Model choice may be limited by the type of species locations or desired inference. Conservation professionals should choose a model and variable set based on the question, the ecology of the species and the availability of requisite data.
The expansion of agriculture in the Brazilian Amazon
- MARCELO FRAGOMENI SIMON, FERNANDO LUIS GARAGORRY
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- Published online by Cambridge University Press:
- 09 January 2006, pp. 203-212
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Recent increase in the rate of deforestation of the Brazilian Amazon has inflamed discussion about the causes of forest loss, with a special focus on agriculture. This paper studies the expansion of agriculture in the Brazilian Amazon from 1976 to 2001 based on the eight most important products (cattle, bananas, beans, cassava, coffee, maize, rice and soybeans). A biological delimitation of the Amazon based on a map of Brazil's biomes was adopted in order to avoid inclusion of non-forested areas in the analysis. Intense spatial changes in Brazilian agriculture have occurred, with the emergence of new production centres for soybeans and cattle. Several of these regions are located nearby or inside the Amazon's limits. Livestock and soybean cropping in Brazil are consistently moving north. The contribution of the Amazon to Brazilian agriculture rose significantly during the last decades, reaching 28.9% of cassava, 21.3% of banana, 14.2% of rice and 20.0% of cattle production in Brazil in 2001 (three-year average). Cropped area and production in the Amazon have grown at higher annual rates than in the rest of the country for almost all items analysed, supporting the view that the region is a new frontier of Brazilian agriculture. Most recent trends point to a vigorous demand for new land, which will consequently imply a predicted increase in forest clearing.
Long-term spatio-temporal dynamics of a hedgerow network landscape in Flanders, Belgium
- B. DECKERS, E. KERSELAERS, H. GULINCK, B. MUYS, M. HERMY
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- 25 April 2005, pp. 20-29
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Although the importance of hedgerows for sustainable agriculture and conservation of rural biodiversity is increasingly being recognized, obtaining insight into the spatial and temporal dynamics of hedgerow networks remains an important challenge for landscape ecologists, with the key factors driving changes in rural landscape structure especially deserving further attention. The present study analyses the long-term history of a hedgerow network landscape in Flanders, Belgium. A detailed reconstruction of the hedgerow network is made at five points in time, starting at the end of the 18th century until present, for 367 distinct 400 m×400 m samples. Whilst hedgerows were mainly concentrated around historical village centres and within valleys at the end of 18th century, the network expanded progressively during the 19th century. In the 20th century, the hedgerow network degraded strongly, with hedgerow density and connectivity declining and mesh-size heterogeneity and network fragmentation increasing, although the network recovered slightly during the 1990s. Different trajectories of change in hedgerow network structure were observed depending on landscape position, with both topography and village proximity significantly affecting hedgerow network dynamics. The present network structure was mainly governed by land use, with highly developed networks being predominantly associated with pasture. Three main conclusions arise from the results of this study. First, the role of land use and landscape position as basic factors steering hedgerow network dynamics at the landscape scale is demonstrated. Second, the long-term perspective of the study enabled insight into the poorly known expansion phase of hedgerow networks, linked mainly with the development of small-scale labour-intensive agriculture. Finally, the findings confirm the large-scale degradation of linear semi-natural habitats in European agricultural landscapes during most of the 20th century, and indicate that a pro-active rural policy can halt and even reverse this process.
Is mahogany dysgenically selected?
- J.P. CORNELIUS, C.M. NAVARRO, K.E. WIGHTMAN, S.E. WARD
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- Published online by Cambridge University Press:
- 15 September 2005, pp. 129-139
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One concern in the ongoing debate over the conservation status of mahogany has been the possibility that selective logging, as a form of negative phenotypic selection, might have led to deterioration in the genetic quality of populations. The incidence and degree of such ‘dysgenic’ effects is discussed, based on a consideration of mahogany logging practices, their expected genetic effects and empirical data on phenotypic selection in forest trees. Loggers have tended to avoid diseased, small, very large and poorly-formed individuals, and consequently logging has tended to increase the proportion of poor quality phenotypes relative to that before logging; in at least some conditions, selection differentials have been strongly negative. However, the upper limit for heritability of logger-selected traits in naturally-regenerated mahogany is probably no more than c. 0.1. Consequently, and assuming relatively extreme but realistic negative selection differentials of 50%, the maximum negative dysgenic response to a single logging-mediated phenotypic selection event is expected to be relatively small, i.e. ≤5%. This expectation is consistent with the empirical information from mahogany and other taxa. The implications of any dysgenic effects depend very much on the use and the future of dysgenically-selected populations. In managed populations, dysgenic effects could be reversed through positive selection. In the case of exploited but currently unmanaged natural populations, dysgenic selection is primarily of importance insofar as it affects fitness. As a threat to mahogany conservation and long-term sustainable production, it is probably insignificant in comparison with other genetic and non-genetic factors.
Magnitude and inferred impacts of the seahorse trade in Latin America
- JULIA K. BAUM, AMANDA C.J. VINCENT
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- 13 December 2005, pp. 305-319
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Seahorses (genus Hippocampus) are traded globally for use in traditional medicines, souvenirs and as aquarium fishes. Indications that the trade was expanding geographically in response to increasing demand in consuming nations prompted this first study of the seahorse trade in Latin America. In 2000, over 400 people related to the seahorse trade in Mexico, Central America, Ecuador and Peru were interviewed. Customs data and other trade records from these and five additional countries or regions trading seahorses from Latin America were obtained. Dried seahorses were exported by almost every surveyed country at some point in the 1990s, with Ecuador, Peru and Mexico exporting hundreds of kg per year over multiple years, and the latter two nations both exporting tonnes of seahorses at least twice. The live seahorse trade was confined to Costa Rica, Mexico, Panama and Brazil; the last dominating this trade and exporting several thousand seahorses annually. Substantial declines in seahorse abundance, attributed primarily to incidental catches in shrimp trawl fisheries, were reported consistently by respondents in many regions. These data contributed to an Appendix II listing on the Convention on International Trade in Endangered Species of Wild Fauna and Flora of all seahorses, thereby requiring that the trade be monitored and controlled. Additional conservation measures are needed to address fishing pressure on seahorse populations.
Human-disturbed landscapes: effects on composition and integrity of riparian woody vegetation in the Tagus River basin, Portugal
- FRANCISCA C. AGUIAR, MARIA TERESA FERREIRA
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- 25 April 2005, pp. 30-41
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Human activities within fluvial corridors and surrounding landscapes have persistently stressed riparian ecosystems, particularly in Iberian Mediterranean-type streams. The impact of human disturbance relative to natural environmental factors in shaping riparian vegetation is still poorly understood. Both regional variables (such as altitude and precipitation), and site-specific characteristics (such as substrate and riverbank modifications) were analysed as potential determinants of riparian vegetation patterning to determine the relative influences of the diverse land-use types and environmental factors on the composition (including floristic species richness and percentage cover of trees, shrubs and woody climbers) and integrity (width of riparian woods and patterns of longitudinal continuity) of riparian woods in eight river basins of the Tagus fluvial system (Portugal). There was patchy establishment of riparian woods, with generally low average width and low species richness, as well as significant inter-basin differences and upstream-downstream variations in riparian features. Species distribution was clearly determined by environmental factors, such as human disturbance on the riverbanks and geological background, and the environmental variables and the land use in the river valley partially explained the integrity of riparian woody vegetation. The results highlight the predictive capability of reach-level features; it appears that, linked with the geomorphological and climate context, small-scale human disturbances on riparian corridors play a major role in explaining the remaining biological variability.
Variation in fishers' attitudes within an inshore fishery: implications for management
- ELIZABETH A. RICHARDSON, MICHEL J. KAISER, GARETH EDWARDS-JONES
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- Published online by Cambridge University Press:
- 24 November 2005, pp. 213-225
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Understanding the incentives influencing the attitudes and behaviour of resource users is a crucial input to the design of institutions for resource management. Typically fishers have been expected to exploit resources in an independent profit-maximizing manner, which is in line with common property theory, although these expectations are not always met because fishers' behaviours and attitudes are generally more heterogeneous than previously considered. Attitudinal differences between participants in the inshore commercial fishery of Wales, UK, were investigated. Semi-structured face-to-face interviews were conducted with 161 fishers from the five main sectors, namely mobile gear fishers, crustacean potters, whelk potters, line/net fishers and transient fishers. Unprompted expressions of attitudes and responses to open-ended questions underwent thematic-coding and were analysed with fishers' responses to structured questions. Investigation into whether the incentive to participate in resource stewardship varied between sectors as predicted by common property theory found attitudinal similarities across the sectors, but also certain important differences. Results suggested an attitudinal continuum, with mobile gear fishers and crustacean potters at the two extremes, and intermediate positions occupied by transient fishers, whelk potters and line/net fishers. Mobile gear fishers believed most strongly that their fishery was controlled too tightly and was impacted by other fishers and other anthropogenic influences. Crustacean potters believed most strongly that conservation of stocks was necessary and that minimum landing sizes were not overcautious. The attitudes that characterized each sector were related to the characteristics of the sector and its resource base, and generally concurred with theoretical predictions. In particular, target species' mobility and past sector experiences predicted the inclination of fishers in each sector towards resource stewardship. The observed attitudinal differences implied varying personal discount rates that may affect how respondents respond to and comply with management tools. Furthermore, attitudinal differences among sectors mean that an effective management tool in one sector may be inappropriate or counterproductive in another.
Predation of artificial Xantus's murrelet (Synthliboramphus hypoleucus scrippsi) nests before and after black rat (Rattus rattus) eradication
- HOLLY P. JONES, R. WILLIAMHENRY III, GREGG R. HOWALD, BERNIE R. TERSHY, DONALD A. CROLL
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- Published online by Cambridge University Press:
- 16 March 2006, pp. 320-325
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Introduced rats depredate every life stage of island nesting seabirds, but the extent of predation is rarely quantified. Introduced black rat (Rattus rattus) and native deer mouse (Peromyscus maniculatus anacapae) predation on Xantus's murrelet (Synthliboramphus hypoleucus scrippsi) nests was experimentally quantified using artificial nests before and after rat eradication on Anacapa Island (California). The staged rat eradication programme provided experimental treatments: in 2002 rats were eradicated on one island (East Anacapa Islet) and remained on two islands (Middle and West Anacapa Islets), providing a control comparison, and, in 2003, rats were eradicated from the remaining islands (Middle and West Anacapa Islets). In 2002, 96% of artificial nests were depredated on control islands (rats present) with rats accounting for most predation. Nest predation on the treatment island (rats eradicated) in 2002 was significantly lower: 8% of artificial nests were depredated, mostly by endemic deer mice. In 2003, following rat eradication on the remaining islands (Middle and West Anacapa Islets), nest predation was reduced from 96% in 2002 to 3% of total nests in 2003. Predation of nests on East Anacapa Islet (rats eradicated in 2002) increased significantly due to reintroduction and recovery of native deer mouse populations, with 23% of artificial nests depredated. The inference is that rat predation on real Xantus's murrelet nests was responsible for the historically low nesting success and small population sizes of breeding murrelets on Anacapa Island. With rats removed, the hatching success of Xantus's murrelet chicks and the number of individuals nesting on Anacapa Island will increase dramatically. Artificial nest studies are particularly well suited to quantifying introduced rat impacts on hole and crevice nesting seabirds and can simultaneously serve as an effective monitoring tool to detect the presence of rats and the recovery of native nest predators.
Agriculture expansion and deforestation in seasonally dry forests of north-west Argentina
- H. RICARDO GRAU, N. IGNACIO GASPARRI, T. MITCHELL AIDE
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- Published online by Cambridge University Press:
- 09 May 2005, pp. 140-148
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In Argentina, deforestation due to agriculture expansion is threatening the Semi-arid Chaco, one of the largest forested biomes of South America. This study focuses on the north-west boundary of the Argentine Semi-arid Chaco, where soybean is the most important crop. Deforestation was estimated for areas with different levels of soil and rainfall limitation for agriculture between 1972 and 2001, with a finer analysis in three periods starting in 1984, which are characterized by differences in rainfall, soybean price, production cost, technology-driven yield and national gross domestic product. Between 1972 and 2001, 588 900 ha (c. 20% of the forests) were deforested. Deforestation has been accelerating, reaching >28 000 ha yr−1 after 1997. The initial deforestation was associated with black bean cultivation following an increase in rainfall during the 1970s. In the 1980s, high soybean prices stimulated further deforestation. Finally, the introduction of soybean transgenic cultivars in 1997 reduced plantation costs and stimulated a further increase in deforestation. The domestic economy had little association with deforestation. Although deforestation was more intense in the moister (rainfall >600 mm yr−1) areas, more than 300 000 ha have already been deforested in the drier areas, suggesting that climatic limitations are being overcome by technological and genetic improvement. Furthermore, more than 300 000 ha of forest occur in sectors without major soil and rainfall limitations. If global trends of technology, soybean markets and climate continue, and no active conservation policies are applied, vast areas of the Chaco will be deforested in the coming decades.
Grit selection in waterfowl and how it determines exposure to ingested lead shot in Mediterranean wetlands
- JORDI FIGUEROLA, RAFAEL MATEO, ANDY J. GREEN, JEAN-YVES MONDAIN-MONVAL, HUGHES LEFRANC, GREGORIO MENTABERRE
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- Published online by Cambridge University Press:
- 11 October 2005, pp. 226-234
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Waterfowl ingest lead shot because they confuse it with grit, but there has been limited study of differences among species and locations. The spatial and interspecific variation in the quantity and size composition of ingested grit and in the ingestion of lead shot by eight waterfowl species in the three main wintering areas in the western Mediterranean (Doñana, Ebro Delta and Camargue) was investigated. Variation in the mass of grit in the gizzard was related to bird species, whereas size composition of ingested grit was more closely related to locality and less to species. Birds with a large proportion of vegetation in their diets had more grit in the gizzard. Grit size composition was related to prevalence of lead shot ingestion. Thus, the quantity of grit in the gizzard is an attribute of species, and grit size composition (which largely determines the risk of ingestion of lead shot) is more affected by local conditions. This conclusion is supported by a meta-analysis of previous studies of the incidence of lead shot ingestion in 51 locations and 27 waterfowl species in North America and Europe. The prevalence of lead shot ingestion in a given waterbird species was highly variable between localities, and was not consistently different between dabbling, grazing and diving species.
Factors influencing resource users and managers' perceptions towards marine protected area management in Kenya
- TIMOTHY McCLANAHAN, JAMIE DAVIES, JOSEPH MAINA
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- Published online by Cambridge University Press:
- 25 April 2005, pp. 42-49
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Non-compliance with marine protected area (MPA) regulations is a problem worldwide, and this is being addressed through community programmes. Park service and fisheries department personnel, and fishers living adjacent to three parks were studied to determine their perceptions of MPAs. The hypotheses that positive perceptions towards the management of fisheries exclusion and gear-restricted areas would increase with the wealth, education, age and years of employment of the person, the history of community participation and the age of the MPA were tested. The strongest factor was employment, with fishers having significantly less positive perceptions towards areas closed to fishing than government managers, although all groups agreed area management benefited the nation. Government personnel thought that fishers and their communities benefited from area management, while most fishers did not share this view. Increasing wealth or community participation were not significant factors, but secondary education was associated with more positive perceptions of area management. Fishers adjacent to the oldest MPA held significantly more positive perceptions than fishers living adjacent to the newest MPA, although only a slight majority agreed that they and their communities benefited. The results point to a need for patience in expecting change in resource users' perceptions, adopting an approach in which there is more communication between fishers and managers, so that both are more aware of MPA functions, particularly closed areas and the indirect benefits.