クルマエビ稚仔に及ぼすLASの毒性 : 急性・亜急性レベルでの病理組織学的研究

東京水産大学資源育成学科東京水産大学資源育成学科東京水産大学資源育成学

Eight basic principles for the elaboration of public policies and development projects for the Pantanal

This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. © 2024 The Author(s). Conservation Science and Practice published by Wiley Periodicals LLC on behalf of Society for Conservation Biology. The Pantanal is considered the largest continuous freshwater wetland in the world, and its sustainable use requires a unified conceptual framework. The lengthy process to establish public policies has contributed to the increasing vulnerability of the Pantanal. Given the need for a conceptual basis to help this process, we elaborate a list of eight basic principles based on the accumulated scientific evidence: (i) Consider the Paraguay River Basin a management unity; (ii) Establish rules that follow the concept of restricted use approach; (iii) Ensure the ecologically sustainable use of the Pantanal; (iv) Maintain the environmental heterogeneity and functionality in the Pantanal landscapes; (v) Maintain the hydrological integrity and connectivity; (vi) Ensure the environmental representativeness of the protected areas network; (vii) Provide economic incentives for conservationist use of the land; and (viii) Recognize and protect traditional people, their values, resources, and way of living. However, the elaboration of public policies should be a participatory and inclusive decision‐making process towards a more just and sustainable future

Evaluation of growth-dependent survival during early stages of Pacific bluefin tuna using otolith microstructure analysis

The present study used otolith analysis-based body size back-calculation to: (1) evaluate the hypothesis of growth-dependent survival in young Pacific bluefin tuna (PBF; Thunnus orientalis) from the north-western Pacific Ocean; (2) identify critical developmental stages for survival; and (3) compare interannual differences in early growth. To this end, we compared the daily growth trajectories of a large number of larvae (standard length (SL) &lt;15mm), juveniles (15≤SL≤150mm), and young-of-year (YOY; SL &gt;150mm) collected between 2011 and 2015. Otolith radius and SL were highly correlated and yielded a single relationship applicable for the five year-classes. Body size back-calculation showed that only larvae with fast, steady growth successfully transitioned to the juvenile stage. The ontogenetic analysis of daily growth rates revealed interannual differences only in larvae, and not in the larval stage of juveniles and YOY. Neither sudden decreases nor increases in growth rates were observed during the larval stage of any of the stages, suggesting that the observed variability in larval body size may be the result of individual differences in growth rates rather than of drastic, one-time events. Overall, the results of the present study indicate that growth-dependent survival of larvae may be the most critical for PBF recruitment. </jats:p

Morphological comparison of wild, farmed and hybrid specimens of two South American silversides, Odontesthes bonariensis and Odontesthes hatcheri

In this study, body shape of hybrid and presumptive introgressed South American silversides was studied. Body shape of O. bonariensis and O. hatcheri from wild populations and farmed stocks was compared to provide basic information on the effects of fish farming on morphometric parameters. Subsequently, wild presumptive introgressed individuals and artificially hybridized farmed individuals were morphologically analysed to assess the effects of hybridization on the same parameters. Most farmed purebred individuals were shorter and higher than their wild counterparts, which is probably due to the favourable growth conditions compared to the wild habitat. However, the results evidenced that purebred individuals were more slender than both hybrid (farmed) fish and introgressed (wild) fish. Further studies on the growth performance of hybrid Odontesthes will be required in order to assess whether the combination of hybridization and sterilization could produce, under farming conditions, growth performances which satisfy the requirements of aquaculture.Fil: Crichigno, Sonia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación En Biodiversidad y Medioambiente; Argentina. Universidad Nacional del Comahue; ArgentinaFil: Shohei Hattori, Ricardo. Tokyo University of Marine Science and Technology; JapónFil: Strussmann, Carlos Augusto. Tokyo University of Marine Science and Technology; JapónFil: Cussac, Victor Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación En Biodiversidad y Medioambiente; Argentina. Universidad Nacional del Comahue; Argentin