Intense Habitat-Specific Fisheries-Induced Selection at the Molecular Pan I: Locus Predicts Imminent Collapse of a Major Cod Fishery

Abstract

Mangrove forests, though essentially common and wide-spread, are highly threatened. Local societies along with their knowledge about the mangrove also are endangered, while they are still underrepresented as scientific research topics. With the present study we document local utilization patterns, and perception of ecosystem change. We illustrate how information generated by ethnobiological research can be used to strengthen the management of the ecosystem. This study was conducted in the Godavari mangrove forest located in the East-Godavari District of the state Andhra Pradesh in India, where mangroves have been degrading due to over-exploitation, extensive development of aquaculture, and pollution from rural and urbanized areas (Kakinada).One hundred interviews were carried out among the fisherfolk population present in two mangrove zones in the study area, a wildlife sanctuary with strong conservation status and an adjacent zone. Results from the interviews indicated that Avicennia marina (Forsk.) Vierh., a dominant species in the Godavari mangroves, is used most frequently as firewood and for construction. Multiple products of the mangrove included the bark of Ceriops decandra (Griff.) Ding Hou to dye the fishing nets and improve their durability, the bark of Aegiceras corniculatum (L.) Blanco to poison and catch fish, and the leaves of Avicennia spp. and Excoecaria agallocha L. as fodder for cattle. No medicinal uses of true mangrove species were reported, but there were a few traditional uses for mangrove associates. Utilization patterns varied in the two zones that we investigated, most likely due to differences in their ecology and legal status. The findings are discussed in relation with the demographic and socio-economic traits of the fisherfolk communities of the Godavari mangroves and indicate a clear dependency of their livelihood on the mangrove forest.Reported changes in the Godavari mangrove cover also differed in the two zones, with significantly less perceptions of a decrease in the protected area, as compared to the adjacent non-protected area. A posteriori comparisons between sequential satellite imagery (retrospective till 1977) and respondents that were at least 15 years back then, revealed a mangrove decrease which was however perceived to different extents depending on the area with which the fishermen were familiar. While local needs had not been incorporated in the existing policy, we created a framework on how data on ethnobotanical traditions, fishery-related activities and local people's perceptions of change can be incorporated into management strategies.

A pesca nos manguezais no Estuário do Rio São Francisco: uma abordagem sócio-ecológica com ênfase no caranguejo Ucides cordatus (Linnaeus, 1763)

“…Nishida et al 2004Ferreira et al, 2009;Souto e Martins, 2009;Firmo et al, 2012;, Cortês et al, 2014) e do mundo (e.g. Dahdouh-Guebas et al, 2006;Satyanarayana et al, 201, 2013 -Neto, 2003;Marrul-Filho, 2003): proteção de parte selecionada dos estoques e limitação de tamanho das capturas . A proteção de parte selecionada dos estoques é um conjunto de medidas que visa possibilitar a existência de um potencial reprodutivo capaz de permitir um adequado recrutamento, e que impossibilite a captura de indivíduos em fases críticas dos seus ciclos de vida .…”

“…Developing sustainable management policies that also consider the subsistence requirements of local people, is a high priority (Dahdouh-Guebas et al, 2006). For this, the integration of indigenous knowledge into contemporary frameworks for conservation and sustainable management of natural resources is become increasingly important in policies on an international and national level (Dahdouh-Guebas and Rist, 2006).…”

“…Local ecological knowledge (LEK) is defined as the knowledge and experience of traditional communities regarding the natural and supernatural worlds that are transmitted orally from one generation to another (Berkes, 1993;Castro, 2000, Cortês et al, 2014. The knowledge derived from traditional fishermen may contribute to strategic ecological managements (Seixas and Begossi, 2001), particularly in research areas with scarce or nonexistent data (Ruddle, 1994;Johannes, 1998; .Considering this, socioecological studies, based on LEK are becoming more and more used to approach mangroves resources and management (Dahdouh-Guebas, et al 2006).…”

“…Vale ressaltar que não apenas o ecossistema manguezal está altamente ameaçado pelos impactos e pressões antrópicas, mas também as comunidades humanas dependente de seus recursos, juntamente com o seu conhecimento sobre o manguezal, também estão ameaçados de extinção, uma vez que ainda estão sub-representados como tema de investigação científica (Dahdouh-Guebas, et al, 2006).…”

“…Por exemplo, em um SSE complexo, subsistemas tais como o sistema de recursos (por exemplo, a pesca em áreas de manguezal), as unidades de recursos (peixes), usuários (pescadores), e sistemas de governança (organizações e regras que regulamentam a pesca naquela costa) são relativamente separáveis mas interagem para produzir resultados a nível do SSE, que por sua vez se retro-alimentam e voltam a afetar os subsistemas e respectivos componentes, bem como outros SES adjacentes (Ostrom, 2009 (Berkes et al 2003; Ban et al, 2013). O desenvolvimento de políticas de gestão sustentável que contemplem também as necessidades de subsistência da população local, é uma alta prioridade, assim estudos sócio-ecológicos sobre manguezais estão se tornando cada vez mais utilizados (Dahdouh-Guebas, et al 2006).…”