Foreword     

Colin E. Nash 《Aquaculture (Amsterdam, Netherlands)》1982,27(3):163-164

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Use of diet and body condition assessments as intermediate indicators of translocation success in the Critically Endangered Philippine crocodile (Crocodylus mindorensis)     

Joseph C. Brown  Matthew H. Shirley  Amante Yog-yog  Merlijn van Weerd  Marites G. Balbas  Bernard A. Tarun  Cameron D. Siler 《水产资源保护:海洋与淡水生态系统》2021,31(10):2817-2829

1. Intermediate metrics of translocation success are useful for long-lived, slow to mature species where survival and reproduction happen over decades.
2. With fewer than 150 individuals in the wild, the Critically Endangered Philippine crocodile (Crocodylus mindorensis) is one of the most threatened species on Earth. This study presents the first analysis of diet and body condition of wild Philippine crocodiles and headstarted (i.e. captive-reared) individuals released into the wild over the last decade, and uses these results to show how diet and body condition can be pertinent intermediate metrics of translocation success.
3. Analyses of stomach contents revealed 17 different aquatic and terrestrial invertebrate and vertebrate prey species. Interestingly, 70% of Philippine crocodiles showed snails to be the predominent prey type, followed by fish (36.7%), birds (33.3%) and reptiles (33.3%). More than 50% of crocodiles consumed the invasive golden apple snail, a leading agricultural pest. Regardless of crocodile history (wild vs. headstarted) or size class (juvenile vs. adult), no evidence was found for dietary differences in percentage occurrence, percentage composition or prey diversity.
4. Body condition was significantly higher in wild compared with headstarted individuals when analysed together in a pooled group, although neither group differed significantly from the standardized expectation, and headstarted individuals were not significantly different when body condition was derived independently for the two groups.
5. This study provides a working example of how assessing the convergence of diet and body condition between translocated and wild individuals can provide complementary monitoring parameters to demonstrate post-release establishment of translocated crocodylians. The congruent dietary composition and comparable body condition observed in this study suggest that headstarted crocodiles adapt well following release.
6. Crocodylus mindorensis survives in an agricultural landscape and is likely to play an ecologically important role by exploiting invasive species, reinforcing the importance of this species to local communities.

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Fluvial maintenance operations in managed alluvial rivers     

Stephen E. Darby  Colin R. Thorne 《水产资源保护:海洋与淡水生态系统》1995,5(1):37-54

• 1 Fluvial maintenance is frequently undertaken to preserve the flood capacity, visual amenity, conservation value and geomorphic stability of managed river channels. Maintenance tasks include the management of both riparian and in-channel vegetation and maintenance dredging.
• 2 Riparian vegetation is traditionally managed by physical methods such as cutting of grasses or removal of trees. Less environmentally severe alternative practices include grazing or shading for grasses, and practices such as pollarding or coppicing for trees.
• 3 While a range of alternative maintenance practices, with varying environmental impact, are usually available for river managers to select, the potential for improving maintenance practices varies according to the particular task considered and the constraints imposed by the need to reach and maintain the target standard of service in terms of flood defence and land drainage.
• 4 This review shows that economic and environmental impacts associated with fluvial maintenance operations may be reduced at three scales. First, at the smallest scale, it is shown that there is often potential for improving the local operational efficiency of individual fluvial maintenance tasks. Second, it may be possible to reduce the intensity of maintenance in channel reaches which are presently over-serviced. Third, at the largest scale, it is shown that efficient maintenance is best achieved within the framework of Integrated Basin Management, and by giving appropriate consideration to future maintenance requirements at the design stage of new projects to reduce the overall need for fluvial maintenance. Examples of the way in which these policies may be implemented to reduce environmental impact without compromising engineering objectives are illustrated through case studies from the UK and the USA.

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Allelic losses and gains during translocations of a high conservation value fish,Coregonus lavaretus     

Kim Præbel  Colin W. Bean  Jennifer A. Dodd  Elizabeth C. Etheridge  Andrew R.D. Gowans  Rune Knudsen  Alexander A. Lyle  Peter S. Maitland  Ian J. Winfield  Colin E. Adams 《水产资源保护:海洋与淡水生态系统》2021,31(9):2575-2585

1. The use of translocations to establish new or ‘refuge’ populations for species with high conservation value is controversial but widely used in conservation management. One of the risks of this approach is that an establishing population does not adequately capture the genetic diversity of the donor gene pool. This effect, rarely examined, is tested here.
2. In this study the genetic consequences of two conservation translocations after five generations (16 years) of the European whitefish, Coregonus lavaretus, were quantified. Both translocations were made using almost the same genetic groups and thus represent a partly replicated natural study.
3. Analysis of 12 informative microsatellites showed that expected heterozygosity, the mean number of alleles per locus and allelic richness did not differ between donor and translocated populations. There was also no loss of heterozygosity in the translocated populations, nor deviations from Hardy–Weinberg equilibrium expectations, nor signs of linkage disequilibrium.
4. All populations were genetically differentiated but pairwise F_ST values were low, indicating that the magnitude of divergence was small.
5. There was no evidence of inbreeding but there were significant differences in private allelic richness between donor and translocated populations. Of 50 alleles found in the donor population, 16% of the rarer alleles were lost in one translocated population and 8% in the other.
6. Allele loss without a reduction in heterozygosity strongly points to stochastic drift effects having occurred following translocation. The evidence indicates that alleles that were not detected in the donor population have arisen de novo in the translocated populations.
7. It is concluded that conservation translocations comprising even a modest number of propagules can successfully capture a high proportion of genetic variation of the host population, and that reduced genetic variation in the translocated population may be mitigated by the emergence of new variation over short time periods.

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Relative importance of environmental gradients and historical trawling effort in determining the composition and distribution of benthic macro-biota in a large inverse estuary     

David R. Currie  Cameron D. Dixon  Shane D. Roberts  Graham E. Hooper  Shirley J. Sorokin  Timothy M. Ward 《Fisheries Research》2011,107(1-3):184-195

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Threatened deer of the world: Research programmes for conservation     

Ian McTaggart Cowan  Colin W. Holloway 《Biological conservation》1974,6(2):112-117

This paper is the sequel to an earlier publication (see Biological Conservation, Vol. 5, No. 4 pp. 243–250, October 1973) on the conservation status of deer and describes an IUCN programme for the conservation of world-threatened deer. Research requirements for conservation of deer that are currently threatened with extinction are discussed. The immediate conservation objective is to ensure the species' or subspecies' survival, and the long-term objective is to restore their productive status in the wild. A framework for research to provide data to guide conservation practices is outlined. It comprises a set of research questions, to aid the planning of studies, and statements of the conservation action potential of the results of these investigations. The proposed organization of the IUCN programme and its current status is described. University and other research institutions that would be interested in participating or co-operating in the programme are invited to write to IUCN.  相似文献   

Advertisers, Exhibitors, and Collaborative Ventures     

Colin E. Harvey 《Veterinary surgery : VS》1985,14(3):2A-2A

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家禽营养中的烟酸   总被引：6，自引：0，他引：6  

Colin Whitehead  李武  李宜 《中国畜牧兽医》2002,29(2):18-21

烟酸 ,又称尼克酸 ,是家禽营养中一个经常被遗忘的维生素。随着禽类遗传潜力的提高 ,有必要根据种类、生产性能和日粮基础成分来重新评估烟酸在日粮中的添加水平。烟酸是氧化还原反应的辅助因子 ,生长家禽缺乏烟酸会使生产性能降低、皮肤损伤、腿骨缩短和跗关节肿大 ,成年蛋鸡的产蛋量和孵化率降低。存在于谷物饲料中的烟酸大多是不能利用的 ,但有关烟酸生物学利用率的数据有限 ,需要更多方面的资料。肉鸡获得最佳生产性能所需烟酸添加量的估计值变化范围很广。但最新的研究结果显示 ,饲喂以小麦为基础日粮的肉鸡 ,烟酸的添加水平最高可达 1…  相似文献   

Dominion Council of Veterinarians     

A. E. Cameron 《Canadian journal of veterinary research》1943,7(1):2

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Evaluating the utility of Arabidopsis thaliana as a model for understanding heterosis in hybrid crops     

David Stokes  Colin Morgan  Carmel O’Neill  Ian Bancroft 《Euphytica》2007,156(1-2):157-171

Despite the phenomenon of heterosis having been used to improve crop productivity for almost a century, there is little understanding of the molecular mechanisms involved. Heterosis has been described recently in the widely used plant model Arabidopsis thaliana. To assess the opportunity afforded by this system, we have developed, through pollination to a male sterile female parent (Ler ms1), a range of hybrids of A. thaliana accessions. We tested this method of hybrid production in A. thaliana by comparing seed produced by natural pollination and hand pollination of emasculated plants. Our results demonstrate that using male sterile lines, which more closely represent methods used for hybrid crop production, circumvents the problems associated with the analysis of hybrids produced from emasculated plants. We identified hybrid combinations exhibiting mid-parent heterosis for vegetative fresh weight ranging from −9 to 103% and characterised heterosis in the reciprocal hybrids of one strongly heterotic combination. We found no evidence of a relationship between the extent of genetic relatedness of A. thaliana accessions and the strength of heterosis exhibited by their hybrids. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献