35 research outputs found

    Female–female aggression : structure of interaction and outcome in loggerhead sea turtles

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    Aggressive behaviour between females of the same species is not widely documented, particularly in marine vertebrates. During a 3 yr in-water survey at the temperate loggerhead sea turtle Caretta caretta breeding area of Zakynthos, Greece, female–female interactions comprised 4% of all female loggerhead sighting events (n = 60 out of 1449 events). Male–female interactions comprised an additional 4% of sighting events, while 92% were of solitary females. The structure of interactions was analysed for 58 of these sighting events, each lasting an average of 3.4 min (SD ± 1) and comprising a total of 3.1 h observation time. We found that interactions involved ritualized escalation in behaviour from passive threat displays (e.g. head–tail circling) to aggressive combat (e.g. sparring). We suggest that circling individuals evaluate opponent size, sparring individuals test opponent strength, and that the positioning of the prehensile tail signals motivational intent to either escalate or abort. The presence of intruder females triggered a passive response in 100% of events involving basking and swimming turtles (n = 19); although residents resting on the seabed only responded on 69% of occasions (n = 27), their response was almost 4 times more likely to escalate to one of aggression. Our results suggest that certain sites may be preferentially sought after and defended by sea turtles

    Conservation hotspots : implications of intense spatial area use by breeding male and female loggerheads at the Mediterranean’s largest rookery

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    The implementation of appropriate protection measures for endangered species in protected areas requires knowledge of their fine-scale habitat use. In May and June of 2006 and 2007, we used GPS loggers (some linked to the Argos system) and a conventional Argos transmitter to track male and female loggerhead turtles Caretta caretta in the vicinity of the breeding area of Laganas Bay within the National Marine Park of Zakynthos, Greece. We obtained (1) 9681 useable locations (mean: 1383 locations ind.–1; range: 519 to 2198 locations) from Tracktag GPS loggers attached to 7 females for a mean duration of 34 d (range: 17 to 52 d); (2) 1245 useable locations (mean: 311 locations ind.–1; range: 38 to 1110 locations) from 4 males fitted with Fastloc Argos tags for a mean duration of 29 d (range: 3 to 51 d) and (3) 100 locations from 1 male fitted with a conventional Argos satellite tag tracked for 128 d. GPS data indicated that before the onset of nesting, both males and females primarily used an area within 500 m of the shore along a core 9 km stretch of coastline, where existing protective legislation requires strengthening. Our observations suggest that a 76.7% female-biased operational sex ratio, measured previously from in-water surveys, may represent a realistic sex ratio estimate in the period before nesting starts. In the first month following the onset of nesting, female spatial distribution remained similar, whereas most males departed for distant areas presumably to forage. Our study provides quantitative evidence of the need to improve the management planning and conservation measures to protect sea turtles in a coastal breeding area, and new insights on male turtle migration

    Development plans versus conservation: explanation of emergent conflicts and state political handling

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    The growing establishment of protected areas incorporating profitable economic activity and conservation initiatives has been characterized by the exacerbation of existent conflicts and the emergence of new ones around them. Over the last two decades the participation of ‘civil society’ in protected areas governance under the mutual goal of sustainable development has become increasingly key to resolving natural resource conflicts. Schinias Greek Natura site, simultaneously national park and Olympic canoeing centre, provides a case study to investigate the roots and outcomes of natural resource conflicts within the context of the coexistence of development and conservation agendas and collaborative governance. Following a grounded-theory approach and drawing on insights from political ecology and environmental governance literature we have been able to reveal the political, socioeconomic, and conservation conflicts arising during implementation of state development and conservation policies. It appears that governmental political handling exacerbated these conflicts, leading to political manipulation to justify policy failure and promote nature privatization. We conclude that conflict resolution compatible with nature protection and social justice cannot occur in isolation from resolving crucial socioeconomic problems, strengthening transparency, and an accurate scientific analysis of the particularities of local communities to guide the formation and implementation of state policies.

    Historical analysis of landscape change using remote sensing techniques: An explanatory tool for agricultural transformation in Greek rural areas

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    The role of agricultural change in transforming Greek rural landscapes is analysed within the broader context and theory of agricultural transition from traditional to productivist and post-productivist regimes. The analysis is based on remote sensing data following a case study approach in two study sites - Tymfi and Konitsa - located in the Epirus mountain area. Vegetation maps were created for 1945, 1969 and 1995 via 'object oriented image analysis' of a series of air-photographs. A number of landscape metrics was then calculated for each map and the interpreted spatial analysis illustrates that the observed landscape changes are linked to agricultural restructure. During the post war period when agriculture in Western Europe had entered a productivist phase, agricultural change was marked by trends of agricultural abandonment predominantly evident in the upland areas. In contrast, farming persisted at the lowlands and the gradual aggregation of crop fields in few large patches, indicates the existence of productivist agriculture. This landscape transformation suggests that productivist agriculture and land abandonment can coexist in a spatially differentiated pattern. Although since the mid-1980s, the rationale of agricultural policy priorities shifted towards post-productivism, the findings of this study do not support the existence of such a transition. The results are further discussed within the broader context of agricultural change in Europe providing an additional dimension to the discussions regarding the spatio-temporal properties of agricultural transition. Understanding the process of agricultural change could enhance the role of agricultural policy as a tool for landscape management and regional planning. (c) 2008 Elsevier B.V. All rights reserved

    Environmental Representations of Local Communities’ Spokespersons in Protected Areas

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    Despite the popularization of the environmental discourse, rural environmental belief-systems should not be viewed as homogenous. Focusing on the largest protected area in Greece, we examined heterogeneity in local environmental views. Local spokespersons elicited word associations to two stimulus terms, namely, ‘environmentalists’ and ‘protected area’. Based on association categories for both terms, we identified two sample segments. ‘Naturalists’ appealed to a naturalistic image, which shaped the core compartment of their representations. On the other hand, ‘skeptics’ provided both environmentalist claims and critical accounts. Our findings revealed that the environmental discourse was widely diffused among local spokespersons. Issues of power and participation in decision-making processes within protected areas are discussed. For instance, dimensions of power and legitimacy were reflected in the frequency of association categories and their allocation among sample segments. Specifically, environmentalist accounts were overtly expressed by both ‘naturalists’ and skeptics, while a more socially, politically and critically inclined view was revealed by a small percentage of associations that were all elicited by ‘skeptics’. We conclude that appreciating the heterogeneity of rural environmental views can reinforce the democratic mandate in environmental policy-making. Copyright © 2009 John Wiley & Sons, Ltd
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