Number Of Breeding Females Research Articles

Breeding Common Scoters Melanitta nigra in Scotland’s Flow Country: a population in decline despite productivity being stable

ABSTRACT Capsule The breeding productivity of the Common Scoter population in Scotland’s Flow Country remained relatively stable during a 44% population decline in Britain and Ireland. Aim To investigate breeding productivity changes in the eastern Flow Country’s Common Scoter population over 22 years and identify possible threats and causes of change during a period of national population decline. Methods Common Scoters from 32 breeding sites were surveyed annually between 2002 and 2023. Each site was visited two to three times in May (pre-nesting period) and two to three times in July and August (post-hatching period) to record the numbers of adult and juvenile Common Scoters. Results Between 2002 and 2023, whilst the Common Scoter population declined (approximately 44% from 27 to 15 breeding pairs) across the study area, breeding productivity (defined as large ducklings per female) remained stable, averaging 0.44 (range of annual means 0.00–1.06) large ducklings per female. The number of small ducklings per female also remained relatively stable. A year of higher breeding productivity did not result in an increase in the number of breeding females in the following years, suggesting that the cause of the population decline lies away from the breeding region. Conclusion Breeding productivity needs to increase, and poor breeding seasons need to be prevented to help maintain this population. The causes of the Common Scoter’s decline away from the breeding area need to be resolved to prevent local extinction. This could be assisted with the removal of non-native forestry plantations in the area, which has been observed to benefit other ground-nesting species by alleviating predation pressure, and by maintaining lake habitat quality, as reflected in shallow water and abundant large invertebrates.

The genetic status and rescue measure for a geographically isolated population of Amur tigers

The Amur tiger is currently confronted with challenges of anthropogenic development, leading to its population becoming fragmented into two geographically isolated groups: smaller and larger ones. Small and isolated populations frequently face a greater extinction risk, yet the small tiger population’s genetic status and survival potential have not been assessed. Here, a total of 210 samples of suspected Amur tiger feces were collected from this small population, and the genetic background and population survival potentials were assessed by using 14 microsatellite loci. Our results demonstrated that the mean number of alleles in all loci was 3.7 and expected heterozygosity was 0.6, indicating a comparatively lower level of population genetic diversity compared to previously reported studies on other subspecies. The genetic estimates of effective population size (Ne) and the Ne/N ratio were merely 7.6 and 0.152, respectively, representing lower values in comparison to the Amur tiger population in Sikhote-Alin (the larger group). However, multiple methods have indicated the possibility of genetic divergence within our isolated population under study. Meanwhile, the maximum kinship recorded was 0.441, and the mean inbreeding coefficient stood at 0.0868, both of which are higher than those observed in other endangered species, such as the African lion and the grey wolf. Additionally, we have identified a significant risk of future extinction if the lethal equivalents were to reach 6.26, which is higher than that of other large carnivores. Further, our simulation results indicated that an increase in the number of breeding females would enhance the prospects of this population. In summary, our findings provide a critical theoretical basis for further bailout strategies concerning Amur tigers.

Study on the Evolution of Genetic Resources of Domestic Animals in Romania

Abstract The paper proposes the identification of animal breeds at risk of abandonment and the analysis of animal genetic resources from the perspective of the evolution of total herds and genetic quality determination programs. Data from the National Institute of Statistics show that in the period 2015–2022, Romania recorded a decline in the total livestock of cattle (−12.34%) and pigs (−32.44%) and slight increases in the total sheep and goats. On the other hand, the National Agency for Animal Husbandry indicates significant decreases in the number of breeding females, both in cattle (−14.7%) and pigs (−32.5%). Within the 4 species of animals analysed (cattle, sheep, goats and pigs), 14 breeds in danger of abandonment were identified, generally native breeds with lower production potential than that of improved breeds. For the identified animal breeds, genetic quality determination programs have been approved, which are implemented by animal breeders’ associations accredited for the establishment and management of Genealogical Registries. Maintaining the genetic diversity of local breeds in danger of abandonment can contribute to the diversification of existing populations, to restoring the vitality of selected lines, to increasing the productivity and disease resistance of animals.

Kinship and similarity drive coordination of breeding-group choice in male spotted hyenas.

When and where animals reproduce influences the social, demographic and genetic properties of the groups and populations they live in. We examined the extent to which male spotted hyenas (Crocuta crocuta) coordinate their breeding-group choice. We tested whether their propensity to settle in the same group is shaped by passive processes driven by similarities in their socio-ecological background and genotype or by an adaptive process driven by kin selection. We compared the choices of 148 pairs of same-cohort males that varied in similarity and kinship. We found strong support for both processes. Coordination was highest (70% of pairs) for littermates, who share most cumulative similarity, lower (36%) among peers born in the same group to different mothers, and lowest (7%) among strangers originating from different groups and mothers. Consistent with the kin selection hypothesis, the propensity to choose the same group was density dependent for full siblings and close kin, but not distant kin. Coordination increased as the number of breeding females and male competitors in social groups increased, i.e. when costs of kin competition over mates decreased and benefits of kin cooperation increased. Our results contrast with the traditional view that breeding-group choice and dispersal are predominantly solitary processes.

Female demographic changes contribute to the maintenance of social stability within a primate multilevel society

Various primate species, including golden snub-nosed monkeys, Rhinopithecus roxellana , form highly complex multilevel social systems. Breeding bands of snub-nosed monkeys maintain stability even though multiple one-male units (OMUs) within a band do not appear to engage in affiliative behaviours among units. As such, female dispersal within breeding bands may be a key factor related to social stability in these complex social systems. However, how individual and group behaviours influence both the formation of this complex social system and the maintenance of social stability within it remain to be fully elucidated. In the current study, based on 16 years of accumulated data, we investigated female dispersal in a wild population of golden snub-nosed monkeys in the Qinling Mountains of China. Using social network analysis and dynamic social modelling, we found that male take-over had no influence on the dominance rank of an OMU, whereas the number of breeding females within an OMU had a significant positive effect on rank. Both the number of breeding females and the number of females entering an OMU had significant positive effects on eigenvector centrality of an OMU. Female dispersal between OMUs decreased the clustering coefficient and reduced the risk of subgroup formation. In addition, female kinship matrices between units were not significantly correlated with association behaviour patterns. Thus, this study sheds light on the internal mechanisms that drive social stability in a complex primate social system. • One-male units in a golden snub-nosed monkey band showed few affiliative behaviours. • Multiple females dispersed among units during the 16-year study period. • Social network analysis showed that female dispersal can maintain social stability. • Female dispersal, not male take-over, affected unit hierarchical rank. • Female kinship did not influence association patterns among one-male units.

Socially Complex Breeding Interactions in Humpback Whales Are Mediated Using a Complex Acoustic Repertoire

Intraspecific conflict can be costly; therefore, many species engage in ritualized contests composed of several stages. Each stage is typically characterized by different levels of aggression, arousal, and physical conflict. During these different levels of “intensity,” animals benefit from communicating potential information related to features such as resource holding potential, relative fighting ability, level of aggression, intent (i.e., fight or flight), and whether or not the competitor currently holds the resource (e.g., a receptive female). This information may be conveyed using both visual displays and a complex acoustic repertoire containing fixed (e.g., age, sex, and body size) and flexible information (e.g., motivation or arousal). Calls that contain fixed information are generally considered “discrete” or stereotyped, while calls that convey flexible information are more “graded,” existing along an acoustic continuum. The use of displays and calls, and the potential information they convey, is likely dependent on factors like intensity level. The breeding system of humpback whales (Megaptera novaeangliae) involves intense male competition for access to a relatively limited number of breeding females (the resource). Here, we investigated the behavior and acoustic repertoire of competitive groups of humpback whales to determine if an increase in intensity level of the group was correlated with an increase in the complexity of the vocal repertoire. We categorized the behavior of humpback whales in competitive groups into three mutually exclusive stages from low to high intensity. While discrete calls were infrequent compared to graded calls overall, their use was highest in “low” and “moderate” intensity groups, which may indicate that this stage of contest is important for assessing the relative resource holding potential of competitors. In contrast, visual displays, call rates, and the use of graded call types, were highest during “high intensity” competitive groups. This suggests that flexible information may be more important in “high intensity” levels as males continue to assess the motivation and intent of competitors while actively engaged in costly conflict. We have shown that the relatively complex social call repertoire and visual displays of humpback whales in competitive groups likely functions to mediate frequently changing within-group relationships.

Population viability analysis of small population: a case study for Asian elephant in China.

Small populations are at risk of extinction from deterministic and stochastic factors. Less than 250 Asian elephants (Elephas maximus) remain in China, and are distributed in a few isolated areas; yet, population viability analyses of this endangered population have not been conducted. Here, the current genetic status of the Pu'Er-Mengyang Asian elephant populations in China was analyzed, and the risk of extinction was predicted over the next 500 years. Factors affecting the viability of this population were determined through simulations. The genetic diversity of the population was very low (mean allele number: 3.1; expected heterozygosity: 0.463), even though a recent population bottleneck was not detected. The effective population size was approximately 24.1 adult elephants. Enough adult breeding individuals exist to maintain population viability. VORTEX simulation model showed that this population would not go extinct in the next 500 years. However, illegal poaching and harvesting could negatively affect population size. A sensitivity analysis showed that the mean stochastic growth rate of the study population is sensitive to sex ratio, number of breeding females, mortality of females of different age classes, carrying capacity, and lethal equivalents. Based on our results, we suggest that action should be taken to alleviate inbreeding and any further loss of genetic diversity, by connecting fragmented elephant habitat or by translocating individual elephants. In addition, human-elephant conflict should be mitigated using various modern approaches, including crop guarding techniques, and by encouraging farmers to switch to crops and income sources not vulnerable to elephant raids.

How can we augment the few that remain? Using stable population dynamics to aid reintroduction planning of an iteroparous species.

Restoration of depleted populations is an important method in biological conservation. Reintroduction strategies frequently aim to restore stable, increasing, self-sustaining populations. Knowledge of asymptotic system dynamics may provide advantage in selecting reintroduction strategies. We introduce interactive software that is designed to identify strategies for release of females that are immediately aligned with stable population dynamics from species represented by 2-, 3-, 4-, and 5-stage life history strategies. The software allows managers to input a matrix of interest, the desired number of breeding females, and the desired management timeline, and calls upon stable population theory to give release strategies that are in concert with both stable population status and the management goals. We demonstrate how the software can aid in assessing various strategies ahead of a hypothetical restoration. For the purpose of demonstration of the tool only, we use published vital rates of an ungulate species, but remark that the selection of species for demonstration is not central to the use of this tool. Adaption of this tool to real-life restorations of any 2-, 3-, 4-, or 5-stage iteroparous species may aid in understanding how to minimize undesirable recovery complications that may naturally arise from transient population dynamics. The software is freely available at: https//cwhl.vet.cornell.edu/tools/stapopd.

Demography of the Neotropical austral migrant Elaenia albiceps chilensis (Tyrannidae) on its breeding grounds: climate and food offer effects

The White-crested Elaenia (Elaenia albiceps chilensis) is a Neotropical austral migrant that breeds in Patagonian forests and overwinter in South America tropics. We investigated White-crested Elaenia demography and the environmental conditions the specie is subjected at the northwest of Patagonia as a first attempt to elucidate its population dynamic. We studied the species abundance, individuals’ body condition, survival, productivity of young and site fidelity according to changes in rainfall patterns and food supply, during three breeding seasons (2009 to 2012). We color banded 361 adult and juvenile White-crested Elaenias. During the first studied season, precipitations were remarkably above the mean and ripe fruit supply was lower than in the other seasons, whereas the abundance of arthropods remained similar along the study. The species abundance decreased 50% across the study, while adult apparent survival rate, the number of breeding females, young productivity and site fidelity were 50% lower in the first season in comparison to the following seasons. Females presented lower body condition at arrival in the first two studied periods. Site fidelity diminished after unfavorable breeding season (i.e. low young productivity and fruit supply), especially for males, although they were more faithful than females and had a slightly higher apparent survival rate. Our results suggest that White-crested Elaenia demography is affected by changes in its main food resource supply (fleshy fruits) during the breeding season, indicating that this part of the annual cycle could be fundamental for its population dynamic.

Breeding site sampling across the Arctic by individual males of a polygynous shorebird.

Males of many polygynous species compete for access to fertile females without providing them with resources other than sperm and without investing in care for the offspring (male dominance polygyny). In such systems, local competition for access to females is intense and typically only a few males obtain matings, leading to strong sexual selection. Sampling multiple breeding areas could then provide a mechanism for males to increase their chances to reproduce. However, little is known about such sampling behaviour and about the spatial scale at which males compete. Here we show that most males of a migratory, polygynous shorebird, the pectoral sandpiper (Calidris melanotos), that arrived at a known breeding location in northern Alaska subsequently moved through a considerable part of the entire species' breeding range (up to 13,045 km in a four-week period), sampling as many as 23 additional potential breeding sites. Our data suggest that males do not have a final breeding destination after migration from their wintering quarters, but make nomadic movements that are probably not a consequence of breeding failure. Tenure, the duration of stay at a site, correlated strongly with the number of breeding females at the site, suggesting that decisions to leave are dependent on local mating opportunities. Nomadic movements may allow males to display and sire offspring at multiple sites within a single breeding season. Sexual selection may then favour high-performance males that are able to reduce sleep to compete locally and to fly long distances between breeding sites, leading to a population with unrestricted interbreeding and without local adaptation and speciation.

The life cycle and number dynamics of the urban mallard population (Anas platyrhynchos, Anseriformes, Aves) in Moscow

The life cycle of the urban mallard (Anas platyrhynchos L.) population of Moscow was monitored from 1998 to 2015. The numbers of the wintering mallards and females with broods, as well as the number of ducklings in each brood, were counted in 150 ponds and 23 rivers of Moscow. The countdown method based on the age of the chicks was used to determine the date of the first laid eggs. During the study period, the crossing of the average daily air temperature of the 0°C threshold moved from the end of March or beginning of April to the end of February, and in recent years, to mid-February (r =–0.44, p = 0.06, n = 18). The number of breeding females over the same period rose from 250 to 900 individuals, whereas the number of mallards wintering in the Moscow inner water bodies increased from 3.8 to 21.5 thousand. The mallards started nesting significantly earlier (r =–0.60, r = 0.008, n = 18). In the years with an early onset of spring, the beginning of breeding in mallards coincided with that of the birds inhabiting the southern regions of Russia. The number of breeding females increased by almost 40% (Z = 2.22, р = 0.02) and the brood size, by 6% (Z = 2.04, р = 0.04). The early onset of spring accounted for 92.3% of the variance in the dates of the start of ovipositin (p < 0.01) and for 55.1% of the variance in the number of breeding females (p < 0.01). The relative number of May broods grew and that of July broods decreased. Over these 18 years, with the number of the nesting females increasing, the brood size decreased (r =–0.46, р = 0.05, n = 18) and the egg-laying period increased (r = 0.56, p < 0.05, n = 18). The total duration of the breeding season in the city exceeds that in different geographical points in nature.

不同草地所有权下家庭牧场生产效率比较分析

PDF HTML阅读 XML下载 导出引用 引用提醒 不同草地所有权下家庭牧场生产效率比较分析 DOI: 10.5846/stxb201408041551 作者: 作者单位: 兰州大学草地农业科技学院;青藏高原生态系统管理国际中心,兰州大学生命科学学院;青藏高原生态系统管理国际中心,兰州大学草地农业科技学院,法国农业研究发展中心,法国 蒙彼利埃,法国农业研究发展中心，法国 蒙彼利埃,法国农业研究发展中心，法国 蒙彼利埃,兰州大学草地农业科技学院 作者简介: 通讯作者: 中图分类号: 基金项目: 中法蔡元培交流合作项目 Comparative analysis of pastoral livestock production of the households with different grassland ownership Author: Affiliation: College of Pastoral Agriculture Science and Technology,Lanzhou University,Lanzhou;China;International Centre for Tibetan Plateau Ecosystem Management,Lanzhou;China,College of Life Sciences, Lanzhou University;International Centre for Tibetan Plateau Ecosystem Management,Lanzhou,College of Pastoral Agriculture Science and Technology,Lanzhou University,Lanzhou,Centre for International Research and Cooperation in Agriculture for Development,Montpellier,,France,Centre for International Research and Cooperation in Agriculture for Development, Montpellier, France,Centre for International Research and Cooperation in Agriculture for Development, Montpellier, France,College of Pastoral Agriculture Science and Technology,Lanzhou University,Lanzhou Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:选取了甘肃祁连山区肃南县春夏秋冬四季草场均已分配到户的15个牧户和天祝县夏秋草场或四季草场均为公共草场的15个农牧户,从草地生态系统生产功能的角度,通过野外调查、DEA模型(数据包络分析模型)分析,比较两地牧民草场面积,冷季补饲,牧工费,家庭劳动力等投入,出售活畜、毛、奶等畜产品的产出等项目,探讨不同的草地所有权下牧民生产效率平均值、效率分布的差异性以及影响生产效率的因素。结果显示:天祝县农牧民生产效率的平均值大于肃南县(P<0.05),且天祝县牧户生产效率的分布优于肃南县。进一步分析得出造成牧业生产效率低的原因从大到小顺序为:补饲投入、能繁母畜、草场面积和劳动力投入。验证了草地所有权会影响家庭牧场生产效率的假设,并且就生产效率角度来说,不完全承包到户的草地所有权优于完全承包到户的。 Abstract:The Tianzhu Tibetan Autonomous County and Sunan Yugu Autonomous County, both located in the Qilian Mountains (Gansu Province), were selected for comparison of the livestock production efficiency between two types of ownership of rangeland. Using the snowball sampling method, 15 households were selected in each county. In the Sunan County, the use of the pasture is allocated to households. Each household has its pastures for the summer, autumn, and winter. In the Tianzhu County, summer and autumn pastures are communal (common). Their use is collective on the village scale. Only the crop land for forage production and winter pastures are allocated to households. The research area, a part of the Qinghai-Tibetan Plateau, has a fragile grassland ecosystem, and livestock is the main source of income for local residents. Grazing is one of the causes of grassland degradation, and the difference in ownership led to different grazing behavior. Grazing activities overseen by herdsmen are determined by grassland ownership, and at the same time, these people are active in livestock production decisions. Accordingly, the objective of this study was to better understand and compare the land status in the two counties, to assess the resulting effects on the livestock productivity in terms of efficiency and to define new kinds of land ownership adapted to the local context. During this research, input and output data within each farm of the sample area were fully collected, such as the size of a pasture, supplementary feed, the number of breeding females, family labor, and the income from selling livestock, wool, milk, and other products. The DEA model (the model of data envelopment analysis) was used to analyze the collected data and to assess livestock production efficiency under different types of land ownership. The following are main conclusions: (1) The average pure technological efficiency of households in the Tianzhu County was higher than that in the Sunan County (0.96 > 0.91), and so was the average scale efficiency (0.86 > 0.70), which resulted in the higher average livestock production efficiency of households in the Tianzhu County than in the Sunan County (0.83 > 0.63; P < 0.05). (2) The percentage of households whose comprehensive efficiency was <0.5 in the Tianzhu County was greater than that in the Sunan County (16.7% > 10%), and so was the percentage of households whose comprehensive efficiency was >0.7 (23.4% > 10%). Thus, the distribution of efficiency was also better in the Tianzhu County. (3) According to these results (excluding the impact of the scale efficiency), redundant input is the main reason for households' low livestock production efficiency. The factors such as feed supplements, the number of breeding females, size of pasture, and family labor have different effects, from strong to weak, on the efficiency of livestock production. In conclusion, status of the rangeland ownership directly affects the livestock production efficiency. The collective use/management is better for improving production efficiency. These results can serve as a reference for local governance in order to develop a more rational system of rangeland ownership, to implement sustainable economic development, and to preserve the ecological environment as well. 参考文献 相似文献 引证文献

Immunocompetence of breeding females is sensitive to cortisol levels but not to communal rearing in the degu (Octodon degus)

One hypothesis largely examined in social insects is that cooperation in the context of breeding benefits individuals through decreasing the burden of immunocompetence and provide passive immunity through social contact. Similarly, communal rearing in social mammals may benefit adult female members of social groups by reducing the cost of immunocompetence, and through the transfer of immunological compounds during allonursing. Yet, these benefits may come at a cost to breeders in terms of a need to increase investment in individual immunocompetence. We examined how these potential immunocompetence costs and benefits relate to reproductive success and survival in a natural population of the communally rearing rodent, Octodon degus. We related immunocompetence (based on ratios of white blood cell counts, total and specific immunoglobulins of G isotype titers) and fecal glucocorticoid metabolite (FGC) levels of adults immunized with hemocyanin from the mollusk Concholepas concholepas to measures of sociality (group size) and communal rearing (number of breeding females). Offspring immunocompetence was quantified based on circulating levels of the same immune parameters. Neither female nor offspring immunocompetence was influenced by communal rearing or sociality. These findings did not support that communal rearing and sociality enhance the ability of females to respond to immunological challenges during lactation, or contribute to enhance offspring condition (based on immunocompetence) or early survival (i.e., to 3months of age). Instead, levels of humoral and cellular components of immunocompetence were associated with variation in glucorcorticoid levels of females. We hypothesize that this covariation is driven by physiological (life-history) adjustments needed to sustain breeding.

Mean ecological conditions modulate the effects of group living and communal rearing on offspring production and survival

Sociality and cooperative rearing may have evolved to increase direct fitness when conditions are challenging to reproduction and/or to reduce environmentally induced variance in fecundity. Examination of these hypotheses comes mostly from studies on singularly breeding birds where reproduction is monopolized by a male–female adult pair. Instead, little is known about plurally breeding species where most group members breed and rear their offspring communally. We used data from an 8-year field study to explore the relationship between the ecology and per capita offspring production and survival (2 components of reproductive success and direct fitness) of the plurally breeding rodent Octodon degus. We determined how mean and variance in food abundance, precipitation levels, degu density, soil hardness, predation risk, and thermal conditions modulated the effects of group size and number of breeding females (potential for breeding cooperation) on reproductive success. The effect of number of females per group on the per capita number of offspring produced was more positive during years with lower mean food and degu density. More positive effects of group size (on per capita number of offspring produced and on per capita surviving offspring) and of the number of females (on per capita number of offspring produced) occurred during years with decreasing mean precipitation levels. Thus, the hypothesis that group living and communal rearing are more beneficial (or less costly) under low mean habitat conditions is supported. In contrast, the social effects on reproductive success seem insensitive to variance in ecological conditions.

Relationships between Long-Term Demography and Weather in a Sub-Arctic Population of Common Eider

Effects of local weather on individuals and populations are key drivers of wildlife responses to climatic changes. However, studies often do not last long enough to identify weather conditions that influence demographic processes, or to capture rare but extreme weather events at appropriate scales. In Iceland, farmers collect nest down of wild common eider Somateria mollissima and many farmers count nests within colonies annually, which reflects annual variation in the number of breeding females. We collated these data for 17 colonies. Synchrony in breeding numbers was generally low between colonies. We evaluated 1) demographic relationships with weather in nesting colonies of common eider across Iceland during 1900–2007; and 2) impacts of episodic weather events (aberrantly cold seasons or years) on subsequent breeding numbers. Except for episodic events, breeding numbers within a colony generally had no relationship to local weather conditions in the preceding year. However, common eider are sexually mature at 2–3 years of age and we found a 3-year time lag between summer weather and breeding numbers for three colonies, indicating a positive effect of higher pressure, drier summers for one colony, and a negative effect of warmer, calmer summers for two colonies. These findings may represent weather effects on duckling production and subsequent recruitment. Weather effects were mostly limited to a few aberrant years causing reductions in breeding numbers, i.e. declines in several colonies followed severe winters (1918) and some years with high NAO (1992, 1995). In terms of life history, adult survival generally is high and stable and probably only markedly affected by inclement weather or aberrantly bad years. Conversely, breeding propensity of adults and duckling production probably do respond more to annual weather variations; i.e. unfavorable winter conditions for adults increase probability of death or skipped breeding, whereas favorable summers can promote boom years for recruitment.

Sperm storage reflects within- and extra-pair mating opportunities in a cooperatively breeding bird

In passerine birds, storage and maturation of sperm takes place in the cloacal protuberance (CP), an external swelling of the reproductive organ. The considerable variation in CP size among species is presumed to be a consequence of varying levels of sperm-competition, but whether individual variation in CP size within a species also reflects sperm competition is not well established. Here, we study temporal variation in male CP size in relation to within-pair and extra-pair mating opportunities and cuckoldry risk in purple-crowned fairy-wrens Malurus coronatus. This is a socially monogamous cooperatively breeding passerine that can breed year-round and has low levels of extra-pair paternity (in 6 % of broods). We show that male CP size sharply increased a few weeks before, and rapidly regressed after his partner laid eggs, consistent with a cost of its maintenance and/or sperm production. Surprisingly, despite low levels of extra-pair paternity, CP size of non-breeding and pre-breeding males was positively correlated with the number of breeding females in the population, suggesting that CP size is sensitive to extra-pair mating opportunities. However, CP sizes do not seem to reflect cuckoldry risk: CP size of dominant males was unaffected by the presence of a subordinate that was unrelated to the dominant female, although those subordinates occasionally sire offspring, and had a larger CP than subordinates living with their mother. Our results suggest that, even in a species with low levels of extra-pair paternity, individual investment in sperm storage reflects both within-pair and, albeit to lesser extent, extra-pair mating opportunities.

Patterns of synchrony in natterjack toad breeding activity and reproductive success at local and regional scales

Empirical studies of the spatiotemporal dynamics of populations are required to better understand natural fluctuations in abundance and reproductive success, and to better target conservation and monitoring programmes. In particular, spatial synchrony in amphibian populations remains little studied. We used data from a comprehensive three year study of natterjack toadBufo calamitapopulations breeding at 36 ponds to assess whether there was spatial synchrony in the toad breeding activity (start and length of breeding season, total number of egg strings) and reproductive success (premetamorphic survival and production of metamorphs). We defined a novel approach to assess the importance of short‐term synchrony at both local and regional scales. The approach employs similarity indices and quantifies the interaction between the temporal and spatial components of populations using mixed effects models. There was no synchrony in the toad breeding activity and reproductive success at the local scale, suggesting that populations function as individual clusters independent of each other. Regional synchrony was apparent in the commencement and duration of the breeding season and in the number of egg strings laid (indicative of female population size). Regional synchrony in both rainfall and temperature are likely to explain the patterns observed (e.g. Moran effect). There was no evidence supporting regional synchrony in reproductive success, most likely due to spatial variability in the environmental conditions at the breeding ponds, and to differences in local population fitness (e.g. fecundity). The small scale asynchronous dynamics and regional synchronous dynamics in the number of breeding females indicate that it is best to monitor several populations within a subset of regions. Importantly, variations in the toad breeding activity and reproductive success are not synchronous, and it is thus important to consider them both when assessing the conservation status of pond‐breeding amphibians.

Assessment of Demographic, Geographical and Genetic Risks in Markhoz Goat Population

Decline of native area, population size and breeding herds are indicators of imminent danger of breed extinction in the near future. Because of occurrence and continuation of these conditions for Markhoz goat population, this research was conducted to determine its spread, latest demographic data and the most important criteria and degree of endangerment. Data were collected through interview with the herders and monitoring the flocks in their native area and other locations in mating season. Distribution map was prepared using GIS and demographic data were used to evaluate Degree of Endangerment (DE). In the latest year, population size, the number of breeding females and males, effective population size and inbreeding rate were 2456, 1332, 70, 266 heads and 0.19% in each generation, respectively. Except for inbreeding rate, other criteria in 2009 were lower than those in 2008. In this study, herders mentioned economic factors as the main reason for decreasing of the population. Investigation of criteria in four major evaluation systems to determine DE showed that Markhoz goat is in demographic and geographical risks and imminent danger of decreasing variation within breed. Intense concentration of 77% of its population within a circle of 7 km radius has exposed the breed at the risk of epidemic diseases and other natural disasters. Thus, the primary conservational measures by the government as well as complimentary studies for providing comprehensive conservation program appear to be necessary.

Secondary sex ratios do not support maternal manipulation: extensive data from laboratory colonies of spiny mice (Muridae: Acomys)

Spiny mice of the genus Acomys (Muridae) represent a very suitable mammalian model for studying factors influencing the secondary sex ratio (SSR). The maternal effort in these rodents is extremely biased in favour of the prenatal period and, therefore, maternal manipulation of the SSR is potentially more advantageous. We studied the SSR in four populations/species of spiny mice kept in family groups consisting of two closely related females, one non-relative male and their descendants. The groups were established from founding animals aged about 3 months (maturing age) and were allowed to breed freely for several months. Each litter was sexed after birth, and relevant data were thoroughly recorded. Altogether, data were collected on 1684 litters: 189 of Acomys sp. from Iran, 203 of A. cilicicus, 875 of A. cahirinus, and 417 of A. dimidiatus. We recorded the sex of 4048 newborns of which 1995 were males and 2053 were females. The overall sex ratio was close to 1:1 (49.2%). Generalized linear mixed models and/or generalized linear models were constructed to evaluate the effect of four life history and eight social variables on the sex ratio. No consistent effects of these variables on the sex ratio were found and, interestingly, none of the variables associated with maternal life history had any effect on the sex ratio. Three factors associated with group composition (i.e. the number of immature males, the number of immature females and the number of breeding females) did have significant effects on the sex ratio, but these effects were not consistent across the studied species. In conclusion, our evaluation of this large dataset revealed that the sex ratio in spiny mice is surprisingly stable.

Amphibian Chytridiomycosis in the Oregon Spotted Frog (RANA PRETIOSA) IN WASHINGTON STATE, USA

In recent years Batrachochytrium dendrobatidis (Bd), a chytridiomycete fungus pathogenic to amphibians (Longcore and others 1999), has been implicated as the proximate cause of amphibian declines around the world (Berger and others 1998; Daszak and others 2003; Muths and others 2003; Pounds and others 2006). Despite the insidious nature of Bd (Green and others 2002), few published data exist addressing its occurrence in the Pacific Northwest (PNW). When Pearl and others (2007) opportunistically examined 7 PNW amphibian species, they found Bd most often (57% of 21 individuals from 14 sampled populations) in the highly aquatic Oregon Spotted Frog (Rana pretiosa), an Endangered Species in Washington State (WDFW 2009). However, all R. pretiosa they sampled were from Oregon, and Bd was not detected in the Rana cascadae (Cascades Frog) and Anaxyrus boreas (Western Toad) specimens they sampled from Washington. Here, we report the detection of Bd in R. pretiosa from Washington. Since 1997 and 1998, respectively, we have been monitoring R. pretiosa populations at the Trout Lake Natural Area Preserve (TLNAP: UTM Zone 10, 610857-612950E, 5095880-5097574N, WGS84; elev. 594 to 599 m) and Conboy Lake National Wildlife Refuge (CLNWR: UTM Zone 10, 625223-635180E, 5086652-5095491N, WGS84; elev. 552 to 576 m), in Klickitat County, Washington. These sites represent 2 of only 3 areas where R. pretiosa is known to occur in Washington (McAllister and Leonard 1997). At both sites, monitoring included egg mass surveys during the annual breeding season following snowmelt (late February to mid-March at CLNWR; midMarch to early April at TLNAP). Surveys involved area-specific counts of individual egg masses and egg mass groups, each of which was marked with flags and geo-referenced using a Geographic Positioning System (GPS) to avoid double-counting. Sampling at CLNWR addressed 4 hydrologically distinct units, which were surveyed repeatedly until no new egg masses were found; at TLNAP, 3 units consistently used for breeding were sampled. We inferred a 1:1 correspondence between egg mass numbers and number of breeding females based on a combination of our direct observations of oviposition (n 5 13), the recapture of non-gravid females known to have laid eggs (n 5 84), and the relatively short interval over which the laying of new egg masses occurs (about 3 wk). Collectively, these data indicate that females lay only 1 clutch annually, and that egg mass numbers reflect the effective population numbers of adult females. Decline in egg mass numbers in 3 of the 4 surveyed units at CLNWR from 2004 to 2005 (Fig. 1) and 2 of the 3 units at TLNAP over the same period (Fig. 2), coupled with the increasing recognition of Bd as a cause of amphibian declines, motivated us to collect dead frogs found during 2006 and test them for Bd. Five dead adult R. pretiosa were tested for Bd; 1 from CLNWR and 4 from TLNAP. The CLNWR specimen collected on 13 March 2006 displayed feeble vital signs, minimal response to touch, and righting response was lacking. The frog died within 20 min of discovery, was preserved in 10% formalin, and then stored in 70% ethanol before histological examination using a standard wet-mount preparation of its epidermal tissue (Berger and others 1999), which was sloughing extensively as multiple epidermal layers. A dead adult female R. GENERAL NOTES