Species-based Conservation Research Articles

Sustained by Snakes? Seasonal Livelihood Strategies and Resource Conservation by Tonle Sap Fishers in Cambodia

This paper situates concerns for conservation of aquatic snakes and livelihood sustainability in Cambodia within a social–ecological systems context and thereby presents a challenge to conventional species-based conservation programmes. Fishing for low-value water snakes has become a widespread activity within the floating communities of Tonle Sap Lake in the last 20 years in response to new market opportunities, provided primarily by a crocodile farming industry. The scale and intensity of this new form of exploitation and reports of declines in catch per fisher have highlighted this activity as a conservation concern, yet its role within local livelihood strategies was previously unknown. We show that it is of increasing importance to the less well-off, and is linked to higher incomes within this group, where it potentially reduces their vulnerability to fluctuations and declines in fish catches. It is particularly important as a means to smooth seasonality of incomes in this flood pulse-driven social–ecological system. We argue that shifts between snake-hunting and fishing, as a market-driven adaptive livelihood strategy by the poor, may be more compatible with wider ecosystem conservation and development goals than alternatives such as increased fishing effort or converting floodplain habitats for seasonal agriculture.

Genetics, taxonomy and the conservation of British Euphrasia

In Britain the genus Euphrasia comprises ca 20 diploid and tetraploid plant species, including several endemics. However, their conservation is impeded by taxonomic uncertainty. Analysis of cpDNA and AFLP variation was used to assess their taxonomic status and establish the extent of barriers to gene exchange among them. Differences in ploidy level constitute a very strong barrier to genetic exchange, although this is not absolute. The diploid endemics E. vigursii and E. rivularis form morphologically and genetically definable units which show some level of reproductive isolation. Within tetraploid Euphrasia, the species showed varying degrees of distinctness. Analysis of geographically paired samples from two widespread outcrossing taxa E. arctica and E. nemorosa provides evidence for extensive genetic exchange between them. However AFLP data indicate that this outbreeding species complex possesses a gene pool distinct from that of the widespread inbreeding tetraploids. The widespread and endemic inbreeding tetraploids contain examples of morphologically and genetically definable taxa, but also species whose distinctness is more equivocal. The conservation implications of this study are that species-based action plans are potentially suitable for conservation of the diploid endemics E. vigursii and E. rivularis. In contrast we contend that a species-based conservation framework, developed with reproductively isolated and genetically distinct groups in mind, requires modification for conservation of the complex and dynamic diversity found within the tetraploids. The adoption of ‘taxonomic’ action plans, designed to protect the evolutionary processes generating Euphrasia diversity, may provide a supplementary solution for conserving this type of variation.

A species approach to marine ecosystem conservation

1. The concept of integrated ecosystem conservation is widely supported as a framework to achieve sustainable management of biodiversity. However, paucity of data and limited methodological tools reduce its application in approaches that integrate scientific knowledge, enhance international cooperation, and promote a rationale that appeals to stakeholders. 2. The landscape species concept (LS), a species-based conservation planning tool developed for patterns and processes of terrestrial conservation, is applied to the Extended Patagonian Marine Ecosystem (E-PME) in the SW Atlantic. The E-PME encompasses the Patagonian continental shelf, shelf break front and part of the Argentine Basin (ca. 3000000km(2)). 3. This ecosystem is influenced by oceanographic patterns of currents and bathymetry as well as by the overlapping geographies of national and international conventions, including those that govern use of the High Seas. The interactions of these oceanographic and jurisdictional structures, and the distribution and seasonal movements of biological species, drive present conservation opportunities and threats. 4. Here, an analysis of 33 candidate species in terms of their area requirements, heterogeneity of their habitat use, vulnerability to threats, ecological functions, and socioeconomic importance is reported, and a suite of 'seascape species' is developed around which to build conservation efforts. Preliminary geographic representations of the human and biological aspects of the seascape are provided, and how their spatial intersection affects conservation approaches is discussed. 5. The application of a focal species approach in an ecosystem framework complements space-habitat perspectives (e.g. the Large Marine Ecosystem concept) and may lead to more efficient planning of marine protected areas.

Mammals on the EDGE: conservation priorities based on threat and phylogeny.

Conservation priority setting based on phylogenetic diversity has frequently been proposed but rarely implemented. Here, we define a simple index that measures the contribution made by different species to phylogenetic diversity and show how the index might contribute towards species-based conservation priorities. We describe procedures to control for missing species, incomplete phylogenetic resolution and uncertainty in node ages that make it possible to apply the method in poorly known clades. We also show that the index is independent of clade size in phylogenies of more than 100 species, indicating that scores from unrelated taxonomic groups are likely to be comparable. Similar scores are returned under two different species concepts, suggesting that the index is robust to taxonomic changes. The approach is applied to a near-complete species-level phylogeny of the Mammalia to generate a global priority list incorporating both phylogenetic diversity and extinction risk. The 100 highest-ranking species represent a high proportion of total mammalian diversity and include many species not usually recognised as conservation priorities. Many species that are both evolutionarily distinct and globally endangered (EDGE species) do not benefit from existing conservation projects or protected areas. The results suggest that global conservation priorities may have to be reassessed in order to prevent a disproportionately large amount of mammalian evolutionary history becoming extinct in the near future.

Conserving taxonomic complexity

Traditional species-based conservation programmes are appropriate in situations where species are readily identifiable. However, in certain taxonomically complex groups of organisms, generally characterized by the presence of uniparental lineages and reticulate evolution, it is not possible to classify biodiversity into discrete and unambiguous species. Attempts to impose species-based conservation on such taxonomically complex groups are proving untenable, and threaten to divert scarce resources and taxonomic expertise from the conservation of other priority groups. We argue here that a new approach should be adopted for taxonomically complex groups. We advocate the conservation of evolutionary processes that generate taxonomic biodiversity, rather than the preservation of a limited number of poorly defined taxa arising from this evolution.

Taxonomic complexity, population genetics, and plant conservation in Scotland

Summary Groups of plants that are undergoing active diversification often do not fall into neat and tidy taxonomies. In such groups it can sometimes be very difficult to establish what does, and what does not, constitute a species. This presents problems for species-based conservation programmes that are based around prioritised species-lists (e.g. the UK Biodiversity Action Plans; BAPs), particularly as the inclusion or exclusion of taxa on these lists largely determines the allocation of conservation resources. This is an important issue as almost half of the BAP priority higher plant species for which Scotland has prime responsibility are taxonomically controversial. Recent research using population genetic approaches to tackle some taxonomically complex plant groups has enhanced our understanding of their biology. Such approaches provide objective and independent assessments of whether a given entity is distinct or not. This information can then be used to contribute towards the decision making proces...

A Century of Green Lessons: The Contribution of Nature Conservation Regimes to Global Governance

This paper reviews the lessons learned over the past 100 years in international management and conservation of the Earth's natural heritage and biological resources (fauna and flora), in the face of growing threats of degradation and extinction. The focus is on the effectiveness of intergovernmental and non-governmental institutions – in terms of agenda-setting, regime formation, implementation and compliance, and reactions to non-compliance. Among specific case histories analysed are the ivory trade ban, the whaling moratorium, and attempts at establishing an international forest regime. Innovative governance features highlighted in the field of global living resource management include active NGO participation, the use of selective economic incentives and disincentives (e.g. multilateral or bilateral trade sanctions), and a number of judicial enforcement remedies for both species-based and area-based conservation agreements. The paper concludes by assessing the prospects of transition from the paradigm of 'permanent sovereignty over natural resources' towards new concepts of public trusteeship and stewardship.