Mendez M.,Columbia University |
Mendez M.,American Museum of Natural History |
Rosenbaum H.C.,American Museum of Natural History |
Rosenbaum H.C.,Wildlife Conservation Society |
And 5 more authors.
PLoS ONE | Year: 2010
Incidental entanglement in fishing gear is arguably the most serious threat to many populations of small cetaceans, judging by the alarming number of captured animals. However, other aspects of this threat, such as the potential capture of motheroffspring pairs or reproductive pairs, could be equally or even more significant but have rarely been evaluated. Using a combination of demographic and genetic data we provide evidence that i) Franciscana dolphin pairs that are potentially reproductive and mother-offspring pairs form temporal bonds, and ii) are entangled simultaneously. Our results highlight potential demographic and genetic impacts of by-catch to cetacean populations: the joint entanglement of motheroffspring or reproductive pairs, compared to random individuals, might exacerbate the demographic consequences of bycatch, and the loss of groups of relatives means that significant components of genetic diversity could be lost together. Given the social nature of many odontocetes (toothed cetaceans), we suggest that these potential impacts could be rather general to the group and therefore by-catch could be more detrimental than previously considered. © 2010 Mendez et al. Source
Barbato B.H.A.,Grande Rio University |
Secchi E.R.,Grande Rio University |
Di Beneditto A.P.M.,State University of Norte Fluminense |
Ramos R.M.A.,Everest Tecnologia em Servicos Ltda. |
And 4 more authors.
Journal of the Marine Biological Association of the United Kingdom | Year: 2012
Four distinct Franciscana Management Areas (FMAs) have been proposed based on several lines of evidence including genotype, phenotype, population response and distribution. To determine if differences in external morphology fit this division, a canonical variate analysis was carried out for males and/or females from FMAs I to IV using up to 14 characters. A total of 78 adult specimens were analysed. More than 90% of the differences between groups were summarized by three canonical variates. Females were larger than males in all areas. Females from FMA IV were of intermediate length between those from FMA I and FMA III and individuals from FMA II were smaller than those from all other areas. Position of dorsal fin and morphology of the anterior body region, differentiate individuals from FMA I and FMA III. Morphological differences found in this study give additional support for the proposed FMAs. Since habitat characteristics and franciscana feeding ecology vary regionally, it is possible that observed morphological differences are due to ecological divergence for niche occupation. The indication of a discontinuous distribution, consistency between genetic and morphological evidence, and a short time genetic divergence, might indicate that franciscanas inhabiting FMA I represent a distinct subspecies. © 2012 Marine Biological Association of the United Kingdom. Source
Waylen K.A.,James Hutton Institute |
Martin-Ortega J.,James Hutton Institute |
Martin-Ortega J.,University of Leeds |
Blackstock K.L.,James Hutton Institute |
And 34 more authors.
Ecology and Society | Year: 2015
Community-based natural resource management (CBNRM) is a concept critical to managing social-ecological systems but whose implementation needs strengthening. Scenario planning is one approach that may offer benefits relevant to CBNRM but whose potential is not yet well understood. Therefore, we designed, trialed, and evaluated a scenario-planning method intended to support CBNRM in three cases, located in Colombia, Mexico, and Argentina. Implementing scenario planning was judged as worthwhile in all three cases, although aspects of it were challenging to facilitate. The benefits generated were relevant to strengthening CBNRM: encouraging the participation of local people and using their knowledge, enhanced consideration of and adaptation to future change, and supporting the development of systems thinking. Tracing exactly when and how these benefits arose was challenging, but two elements of the method seemed particularly useful. First, using a systematic approach to discuss how drivers of change may affect local social-ecological systems helped to foster systems thinking and identify connections between issues. Second, explicitly focusing on how to use and respond to scenarios helped identify specific practical activities, or “response options,” that would support CBNRM despite the pressures of future change. Discussions about response options also highlighted the need for support by other actors, e.g., policy groups: this raised the question of when and how other actors and other sources of knowledge should be involved in scenario planning, so as to encourage their buy-in to actions identified by the process. We suggest that other CBNRM initiatives may benefit from adapting and applying scenario planning. However, these initiatives should be carefully monitored because further research is required to understand how and when scenario-planning methods may produce benefits, as well as their strengths and weaknesses versus other methods. © 2015 by the author(s). Published here under license by the Resilience Alliance. Source