727 research outputs found

    Rescue of the Seychelles warbler on Cousin Island, Seychelles:The role of habitat restoration

    Get PDF
    Management policies to save threatened species are not always successful, often due to the lack of a scientific basis and evaluation of the species response. We describe the ecological studies and the conservation actions taken between 1985 and 1992 on Cousin Island (29 ha, Seychelles) to safeguard the future of the highly threatened Seychelles warbler (Acrocephalus sechellensis), which until 1988 only occurred on this island. A detailed field study was designed to (1) identify the key processes influencing warbler demography, (2) identify appropriate management techniques to increase the warbler population, and (3), assess the influence of the resulting habitat management. Since 1980 the island has been saturated with c. 115 territories and c. 320 birds. The warbler is purely insectivorous. Morinda (Morinda citrifolia), the most insect rich tree, is preferred for foraging. The higher the insect abundance (and Morinda cover) in territories the higher the reproductive success and survival of warblers. Insect numbers were highest in the central part of Cousin and decreased towards the coast. Coastal territories protected by a salt tolerant hedge of Scaevola (Scaevola taccada) had more insects and higher reproductive success than unprotected territories. Between 1990 and 1992 Morinda trees were planted on the island and Scaevola along the coast. Although these habitat restoration measures have not resulted in higher numbers of adult warblers and territories due to habitat saturation, they have been successful in terms of improving the quality of existing breeding territories and with that the reproductive success of breeding birds (including the number of territories producing recruits), and the exchange of individuals (genetic material) between territories. We provide evidence that the high reproductive potential of this species is likely to improve the resilience of the species to catastrophic events. (c) 2005 Elsevier Ltd. All rights reserved

    The role of shared intentions in the emergence of service ecosystems

    Get PDF
    With the increased prevalence of ecosystems across sectors, understanding what conditions enable their formation is important for both researchers and managers. Service-dominant logic (S-D logic) focuses on service ecosystems, in which actors are interdependent, and characterizes them as layered and nested within three levels (micro, meso, and macro). To understand their formation, this study draws from work in philosophy and the social sciences to introduce the concept of shared intentionality, an aspect of collective agency whose specific conditions result from and foster interdependence among actors, and to acknowledge the mediating role of the meso level in emergence. With these concepts, this study addresses a research question on how service ecosystems are formed and what role individual and collective agency play in this process. This study contributes to S-D logic research by offering a new understanding of service ecosystem formation as a process of emergence in which the development of shared intentions enables collective agency. To synthesize the contribution, this study uses a case to illustrate a conceptual framework in which the sharing of intentions among interdependent actors drives service ecosystem emergence step-by-step across distinct dynamic levels
    • …
    corecore