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1.
The salt marsh harvest mouse (Reithrodontomys raviventris) is an endangered species, endemic to the marshes of the San Francisco Bay, California, USA. This species is thought to feed primarily on pickleweed (Salicornia pacifica), although its diet is poorly understood, and a large proportion of remaining habitat for salt marsh harvest mice is managed for non-pickleweed vegetation to provide habitat for waterfowl. Using 2 sets of cafeteria trials, we tested food preferences of the salt marsh harvest mouse when offered a variety of plants and invertebrates from the Suisun Marsh, Solano County, California. In a set repeated menu, and unique seasonal menus, salt marsh harvest mice showed strong preferences for food types commonly grown for waterfowl, and also for non-native plants; in contrast, pickleweed was the most preferred during only some of the set and some of the seasonal trials. These results suggest that salt marsh harvest mice have a more flexible diet than previously thought, and will allow land managers in areas such as the Suisun Marsh to promote the growth of plants that provide foods that are preferred by both waterfowl and salt marsh harvest mice. © 2019 The Authors. The Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society.  相似文献   

2.
JAMES H. PATTERSON 《Ibis》1995,137(S1):S215-S218
Bird conservation is a global environmental issue which requires innovative approaches to species and habitat protection and management and the promotion of sustainable development practices. This paper presents some of the highlights in the evolution of two programmes, what may or may not have made them succeed, what lessons were learned and what recommendations can be made for the future of bird conservation. The evolution of the North American Waterfowl Management Plan (NAWMP) and Wetlands for the Americas (WA) bears a lot of similarity to the evolution of International Waterfowl and Wetlands Research Bureau and Ramsar.  相似文献   

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Species conservation requires an understanding of the factors and interactions affecting species distribution and behavior, habitat availability and use, and corresponding vital rates at multiple temporal and spatial scales. Opportunities to investigate these relationships across broad geographic regions are rare. We combined long-term waterfowl population surveys, and studies of habitat use and breeding success, to develop models that identify and incorporate these interactions for upland-nesting waterfowl in the Prairie Pothole Region (PPR) of Canada. Specifically, we used data from the annual Waterfowl Breeding Population and Habitat Survey (1961–2009) at the survey segment level and associated habitat covariates to model and map the long-term average duck density across the Canadian PPR. We analyzed nest location and fate data from approximately 25,000 duck nests found during 3 multi-year nesting studies (1994–2011) to model factors associated with nest survival and habitat selection through the nesting season for the 5 most common upland nesting duck species: mallard (Anas platyrhynchos), gadwall (Mareca strepera), blue-winged teal (Spatula discors), northern shoveler (Spatula clypeata), and northern pintail (Anas acuta). Duck density was highly variable across the Canadian PPR, reflecting positive responses to local wetland area and count, and amounts of cropland and grassland, a regional positive response to latitude, and a negative response to local amounts of tree cover. Nest survival was affected by temporal and spatial variables at multiple scales. Specifically, nest survival demonstrated interactive effects among species, nest initiation date, and nesting cover type and was influenced by relative annual wetness, population density, and surrounding landscape composition at landscape scales, and broad geographic gradients (east-west and north-south). Likewise, species-specific probability of nest habitat selection was influenced by timing of nest initiation, population density, relative annual wetness, herbaceous cover, and tree cover in the surrounding landscape, and location within the Canadian PPR. We combined these models, with estimates of breeding effort (nesting, renesting, and nest attempts) from existing literature, in a stochastic conservation planning model that estimates nest distribution and success given spatiotemporal variation in duck density, habitat availability, and influential covariates. We demonstrate the use of this model by examining various conservation planning scenarios. These models allow estimation of local, landscape, and regional influence of conservation investments and other landscape changes on the productivity of breeding duck populations across the PPR of Canada. These models lay the groundwork for the incorporation of conservation delivery costs for full return-on-investment analyses and scenario analyses of climate, habitat, and land use change in regional and continental population models.  相似文献   

5.
This paper examines the relation between public land management policy, amenity migration, and socioeconomic well-being using the case of the Northwest Forest Plan—a forest management policy that caused 11.6 million acres of federal land in the US Pacific Northwest to be reallocated from commodity production to biodiversity services. Our analysis focuses on three propositions implicit in much of the amenity migration literature in the USA: land management policies that reduce commodity production and/or increase environmental protection (1) improve the natural amenity values of public lands; (2) increase amenity migration to communities near public lands; and (3) stimulate economic development and increase socioeconomic well-being in these communities. Our findings indicate that all three propositions are problematic and demonstrate the importance of community-scale analysis for understanding the relation between land management policies, amenity migration, and community well-being. We discuss the implications of our findings for public land management and rural community development.
Ellen M. DonoghueEmail:
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6.
采用微卫星分子标记对中华水韭(Isoetessinensis)安徽休宁、浙江建德和东方水韭(I.orientalis)浙江松阳三个孑遗居群的迁地保护居群开展了遗传多样性检测与遗传结构分析。7对多态性微卫星引物在36个迁地保护亚居群的720个样本中共检测到59个等位基因,每位点平均等位基因数(A)为8·43。迁地保护亚居群均维持很高的遗传多样性,多态信息含量(PIC)平均为0·707。迁地保护亚居群间遗传分化较低,遗传分化系数GST仅为0·070,居群间具有较大基因流(Nm=3·59)。单因素方差分析发现水韭孢子或孢子体在沿主要水流方向上的长距离传播能力要强于弱水流方向上的短距离传播能力,水流动态对水韭植物的基因流有重要影响。这与UPGMA聚类分析中迁地保护亚居群按邻近位置或水流相通程度优先聚类的结果相一致,水流所带动的强大基因流导致了不同孑遗居群来源的迁地保护亚居群间的遗传混杂。建议在开展水韭植物的迁地保护或回归自然重建时,对具有地方适应分化或者显著性进化的水韭植物居群应相互隔离而不宜配置在一起,以避免远交衰退的遗传风险。  相似文献   

7.
The large land snail Placostylus ambagiosus (Pulmonata: Bulimulidae) was investigated during a long-term study in northernmost New Zealand. The snails fed at night on fallen leaves from a variety of broadleaf trees and bushes. During the day, most snails in shrubland rested under plants close to their food sources at densities of up to 53 snails per m2 and mean live biomasses of 47–72 g/m2. Individual snails stayed close to their food plants for up to 12 years, seldom moving away. Resting behaviour and site fidelity in forest was not investigated in detail, but some adult snails in forest returned to their original sites after being moved up to 60 m into a fenced area built to protect them from feral domestic animals. The ovoid eggs (mean 7.0 mm long×5.6 mm wide; ranges 5.5–7.7 mm long; 5.1–6.7 mm wide) were laid in clutches averaging 43 eggs (range 1–113 eggs) in shallow cavities covered with soil. More than one snail may contribute to a clutch. Adult shell height ranged from 43 mm to 97 mm and varied with habitat quality. Where snail abundance was high adults were small. Implications of these results for conservation management are discussed.  相似文献   

8.
North American field crickets (genus Gryllus) exhibit a diversity of life cycles, habitat associations, and calling songs. However, patterns of evolution for these ecological and behavioral traits remain uncertain in the absence of a robust phylogenetic framework. Analyses of morphological variation have provided few clues about species relationships in the genus Gryllus. Here we use comparisons of mitochondrial DNA restriction site maps for 29 individuals representing 11 species (including potential outgroups) to examine relationships among eastern North American field crickets. Initially chosen as likely outgroup taxa, the two European species of Gryllus do not obviously fall outside of an exclusively North American clade and (based on amount of sequence divergence) appear to have diverged from North American lineages at about the same time that major North American lineages diverged from each other. The egg-overwintering crickets comprise a strongly supported monophyletic group, but relationships among these three closely related species cannot be resolved. The mtDNA data are consistent with a single origin of egg diapause and do not support a model of recent life cycle divergence and allochronic speciation for Gryllus pennsylvanicus and G. veletis. The two crickets are not sister species, despite remarkable similarity in morphology, habitat, and calling song. This conclusion is consistent with published data on allozyme variation in North American field crickets. The habitat associations of eastern North American field crickets have been labile, but calling songs sometimes have remained virtually unchanged across multiple speciation events.  相似文献   

9.
The importance of Indigenous peoples’ and their ancestral estates for the maintenance and protection of biodiversity, ecosystem function, threatened species and cultural diversity is clear. Due to their nature, processes and tools to measure the impact of intercultural Indigenous land and sea management partnerships need to be innovative and adaptable. In 2015, the Wunambal Gaambera Healthy Country Plan reached its mid‐point, which triggered an evaluation to enable adaptive management through the assessment of effectiveness. The evaluation was used to appraise the need for adaptation, contribute to the evidence base for healthy Country, and to report on achievements. The Uunguu Monitoring and Evaluation Committee, an innovative, intercultural and interdisciplinary body, and their collaborators adopted a multiple evidence‐based approach to enable an enriched picture. This committee has successfully integrated western scientific and local Indigenous knowledge for adaptive management by embodying the principles of co‐production. The Uunguu Monitoring and Evaluation Committee model outlines a way of doing knowledge integration from the bottom up which, given the significance of the cultural and natural diversity of the Indigenous estate, makes a valuable contribution to the global community of practitioners attempting to use diverse knowledges for better management of biodiversity, ecosystems, threatened species and cultural traditions.  相似文献   

10.
Coregonine fishes are notorious taxonomicproblems due to their extreme morphological andecological variation. In North America, diversity is particularly baffling among ciscoes, and both morphological and phylogenetic analyses have resulted in major polytomy among the 8 taxa of the ``Coregonus artedi' species complex. Ciscoes arealso a devastated group, accounting for 10% ofthe fish species listed by the Committee on theStatus of Endangered Wildlife in Canada. Here,we complete the genetic characterization ofNorth American ciscoes with mitochondrial andmicrosatellites markers previously used toanalyse populations of C. artedi in orderto elucidate the evolutionary history andidentify appropriate conservation units. Ourresults revealed a complex evolutionary historymarked by postglacial reticulation eventscoupled with recent and independent evolutionof similar phenotypes (taxa). Genetic variationreflects geography rather than taxonomy, andconsequently, we recommend that a single taxon,C. artedi (sensu lato) be recognized.Local genetic differentiation is often coupledwith ecophenotypic diversification, and gillraker polymorphisms, depth-related habitatpreference and reproductive behaviour areconsidered as phenotypic traits with probableadaptive value contributing to the nicheexpansion of ciscoes. Ecomorphotypes of eachparticular locale thus represent a uniqueexpression of a diverse genetic pool stillundergoing divergence and sorting.Consequently, ciscoes from lakes with distinctecomorphotypes are recognized as ESUs, as wellas each of sympatric forms when they aregenetically differentiated. We recommend thatan ESU strategy focusing at a very local levelbe adopted for continental ciscoes as a validalternative to protect significant evolutionaryprocesses of divergence encountered inpolytypic species of newly colonized habitats.  相似文献   

11.
We performed population genetic analyses on the American eel (Anguilla rostrata) with three main objectives. First, we conducted the most comprehensive analysis of neutral genetic population structure to date to revisit the null hypothesis of panmixia in this species. Second, we used this data to provide the first estimates of contemporary effective population size (Ne) and to document temporal variation in effective number of breeders (Nb) in American eel. Third, we tested for statistical associations between temporal variation in the North Atlantic Oscillation (NAO), the effective number of breeders and two indices of recruit abundance. A total of 2142 eels from 32 sampling locations were genotyped with 18 microsatellite loci. All measures of differentiation were essentially zero, and no evidence for significant spatial or temporal genetic differentiation was found. The panmixia hypothesis should thus be accepted for this species. Nb estimates varied by a factor of 23 among 12 cohorts, from 473 to 10 999. The effective population size Ne was estimated at 10 532 (95% CI, 9312–11 752). This study also showed that genetically based demographic indices, namely Nb and allelic richness (Ar), can be used as surrogates for the abundance of breeders and recruits, which were both shown to be positively influenced by variation during high (positive) NAO phases. Thus, long‐term genetic monitoring of American glass eels at several sites along the North American Atlantic coast would represent a powerful and efficient complement to census monitoring to track demographic fluctuations and better understand their causes.  相似文献   

12.
This article details the complex natural and cultural history of red wolf (Canis rufus) restoration in the American South. The decisions and methods utilized in the red wolf’s recovery after 1960 were unprecedented and creative but not geographically limited. The federal red wolf recovery experiment highlights the debate over what constitutes a species in a dynamic world, and the practical challenges and unexpected results in endangered species management in peopled landscapes. This wildlife restoration story illustrates not only the “hands-on” management role humans played, and continue to play, but also reveals cultural assumptions about what constitutes a “wild” wolf and about the necessity of wilderness. The red wolf recovery project provides constructive lessons for future species restoration involving flora and fauna on public and private land, and demonstrates human and animal engagement in the making of nature and culture.  相似文献   

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