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Noninvasive faecal DNA sampling has the potential to provide a wealth of information necessary for monitoring and managing endangered species while eliminating the need to capture, handle or observe rare individuals. However, scoring problems, and subsequent genotyping errors, associated with this monitoring method remain a great concern as they can lead to misidentification of individuals and biased estimates. We examined a kit fox scat data set (353 scats; 80 genotypes) for genotyping errors using both genetic and GIS analyses, and evaluated the feasibility of combining both approaches to assess reliability of the faecal DNA results. We further checked the appropriateness of using faecal genotypes to study kit fox populations by describing information about foxes that we could deduce from the 'acceptable' scat genotypes, and comparing it to information gathered with traditional field techniques. Overall, genetic tests indicated that our data set had a low rate of genotyping error. Furthermore, examination of distributions of scat locations confirmed our data set was relatively error free. We found that analysing information on sex primer consistency and scat locations provided a useful assessment of scat genotype error, and greatly limited the amount of additional laboratory work that was needed to identify potentially 'false' scores. 'Acceptable' scat genotypes revealed information on sex ratio, relatedness, fox movement patterns, latrine use, and size of home range. Results from genetic and field data were consistent, supporting the conclusion that our data set had a very low rate of genotyping error and that this noninvasive method is a reliable approach for monitoring kit foxes. 相似文献
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Small captive populations are likely to become extinct. Detailed breeding plans based on the principles of population genetics and demography can greatly increase their chances of long-term survival. Zoos have now begun to implement such plans but lack the resources to extend them to the many species that are likely to become extinct in the wild in the near future. 相似文献
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Laura D. Bertola;Anna Brüniche-Olsen;Francine Kershaw;Isa-Rita M. Russo;Anna J. MacDonald;Paul Sunnucks;Michael W. Bruford;Carlos Daniel Cadena;Kyle M. Ewart;Mark de Bruyn;Mark D. B. Eldridge;Richard Frankham;Juan M. Guayasamin;Catherine E. Grueber;Thierry B. Hoareau;Sean Hoban;Paul A. Hohenlohe;Margaret E. Hunter;Antoinette Kotze;Josiah Kuja;Robert C. Lacy;Linda Laikre;Nathan Lo;Mariah H. Meek;Joachim Mergeay;Cinnamon Mittan-Moreau;Linda E. Neaves;David O'Brien;Joel W. Ochieng;Rob Ogden;Pablo Orozco-terWengel;Mónica Páez-Vacas;Jennifer Pierson;Katherine Ralls;Robyn E. Shaw;Etotépé A. Sogbohossou;Adam Stow;Tammy Steeves;Cristiano Vernesi;Mrinalini Watsa;Gernot Segelbacher; 《Conservation Science and Practice》2024,6(1):e13053
Molecular tools are increasingly applied for assessing and monitoring biodiversity and informing conservation action. While recent developments in genetic and genomic methods provide greater sensitivity in analysis and the capacity to address new questions, they are not equally available to all practitioners: There is considerable bias across institutions and countries in access to technologies, funding, and training. Consequently, in many cases, more accessible traditional genetic data (e.g., microsatellites) are still utilized for making conservation decisions. Conservation approaches need to be pragmatic by tackling clearly defined management questions and using the most appropriate methods available, while maximizing the use of limited resources. Here we present some key questions to consider when applying the molecular toolbox for accessible and actionable conservation management. Finally, we highlight a number of important steps to be addressed in a collaborative way, which can facilitate the broad integration of molecular data into conservation. 相似文献
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Robert L. Brownell Jr. Katherine Ralls † Simone Baumann-Pickering ‡ M. Michael Poole § 《Marine Mammal Science》2009,25(3):639-658
Southall et al . (2006) concluded that a near mass stranding (MS) of melon-headed whales (MHWs), Peponocephala electra , in Hanalei Bay, Kauai, Hawaii, on 3–4 July 2004, was likely related to the operation of mid-frequency sonars (MFS). However, subsequent authors argued that the nearly simultaneous entry of MHWs into Sasanhaya Bay, Rota (∼5,740 km away) made this conclusion untenable. They suggested that both sightings, and other MSs of MHWs, could be related to lunar cycles. To resolve this question, we reviewed information on the biology and behavior of MHWs and compared the two sightings to observations of MHWs around Palmyra Atoll and Nuku Hiva, French Polynesia. We also tested for a relationship between observations and MSs of MHWs with lunar cycles. MHWs near many oceanic islands rest nearshore during the day and feed offshore in deeper water at night. The MHWs at Rota exhibited normal diurnal resting behavior as seen at Palmyra and Nuku Hiva, while those at Kauai showed milling behavior typically seen prior to MS events. Thus, these events were not similar. Neither observations nor MSs of MHWs were related to lunar cycles. Our review of MHW behavior strengthens the case that MFS use played a major role in the near MS in Hanalei Bay. 相似文献
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AN INTRAPERITONEAL RADIO TRANSMITTER FOR SEA OTTERS 总被引：1，自引：0，他引：1
Katherine Ralls Donald B. Siniff Thomas D. Williams V. B. Kuechle 《Marine Mammal Science》1989,5(4):376-381
A small intraperitoneal radio transmitter was developed and used successfully in California sea otters. The transmitter weighs about 120 g and has an internal antenna. Thirty-five implanted transmitters were located for an average of 526 d. The carcasses of five animals that died were recovered; there were no complications associated with the transmitters in these individuals. Reproductive performance of the adult females with implanted transmitters appeared normal. The main advantages of this transmitter are its reliability and long life. It has enabled the collection of significant new information on California sea otters. 相似文献
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Sara V. Good Daniel F. Williams Katherine Ralls Robert C. Fleischer 《Evolution; international journal of organic evolution》1997,51(4):1296-1310
The giant kangaroo rat, Dipodomys ingens (Heteromyidae), is an endangered rodent that inhabits approximately 3% of its estimated historic range. Its current distribution is centered in two geographic areas, situated about 150 km apart, in south-central California. We sequenced a 293 base-pair fragment at the 5' end of the control region in 95 giant kangaroo rats from nine localities to examine the genetic structure of extant populations. We determine that mutations in this section of the control region follow a negative binominal distribution, rather than a Poisson. However, the distance between haplotypes is small enough that the difference between a tree that corrects for the non-Poisson distribution of mutations and one that does not, is minimal. This implies that the use of methods that assume a Poisson distribution of mutations, such as those based on coalescent theory, are justified. We find that the correlation between levels of genetic diversity and estimated census size is poor. This suggests that population sizes have fluctuated over time or that populations have not been isolated from one another, or both. We also examine the hierarchical structure of populations and find that the southern populations are not genetically subdivided but that there is significant subdivision between northern and southern populations and between some northern subpopulations. The phylogeographic relationship between northern and southern populations can primarily be attributed to isolation by distance, although the time since divergence between them appears to be less than the age of either. To examine the phylogeographic relationships in more detail we construct a minimum spanning tree based on Tamura-Nei gamma-corrected distances and superimpose on it the geographic position of haplotypes. This reveals that there is more genetic distance between some northern haplotypes than between any northern and southern haplotypes, despite the geographic distance separating north from south and the larger size of the southern population. It also reveals that one northern population, in the Panoche Valley, contains old allelic lineages and shares ancestral polymorphism with several other populations. It also shows that two, small, geographically remote populations contain a surprising amount of genetic diversity, but that different population/geographic processes have affected the structure of that diversity. We estimate the average migration rate among all populations to be 7.5 per generation, and conclude that a disproportionate number of migration events involve gene flow with one northern population, the Panoche Valley. We find evidence for the hypothesis that there has been an increase in population size in the remaining populations in the north and suggest that the Panoche Valley could play a role in these expansions. Finally we discuss the probabilitiy that the genetic structure of the southern populations has been affected by fluctuations in size. These results are briefly compared to other studies on the genetic structure of rodent populations. 相似文献