Reproductive and dietary parameters in wild greater galago populations

Information concerning habitat, body size, reproductive status, and diet was recorded from 348 greater galagos, captured at six different localities in Tanzania and southern Africa between 1953 and 1955. The localities extended from Pemba Island in the north to Chikwawa, Malawi, in the south and varied broadly in the same order in degree of climatic aridity— from well-watered clove and coconut plantations to seasonally very dry woodland. Animals from the three northern localities fell within the geographic range of Galago garnettii,while the rest were assumed to be G. crassicaudatus.Statistical analysis of body size parameters confirmed this allocation. Data on fetal occurrence, vaginal and labial condition, and lactation indicate a restricted breeding season for both species, with peak proportions in estrus in August in G. garnettiiand in May-July in G. crassicaudatus.Gut content data indicate a variety of foods, with a preponderance in the northern localities of soft fruit such as mango, pawpaw, and coconut pulp; gum was a major carbohydrate source in the southernmost localities. Contrary to expectations, tooth damage, in the form of both loss and breakage, was much more prevalent in G. garnettiithan in G. crassicaudatus.The teeth most commonly lost were the upper incisors— perhaps because of the high acid and sugar content of a frugivorous diet. The high incidence of breakage of the lower incisors and upper canines indicates the inclusion of hard-shelled food sources in the diet of G. garnettii.     

Using harvest data to predict habitat-population relationship of the wild boarSus scrofa in Northern Italy

The relationships between the wild boarSus scrofa, Linnaeus 1758 density and the habitat characteristics were investigated by collecting bag records in 18 hunting areas during the 1995 and 1996 hunting seasons. The study areas were located in the Northern Apennines (N-Italy) from 470 to 1160 m a.s.l. In each study area a Density Index (DI) was calculated by weighting the number of wild boar culled in each hunting season on the number of hunting days and on the surface of the study areas. Moreover 16 habitat variables were measured in each study area. Correlation and regression analyses were performed considering the DI as a dependent variable. Mixed deciduous woods were positively correlated with wild boar density together with chestnuts woods and conifer reafforestations. No significant negative correlations were found. Twelve multiple regression models each including three habitat variables were ranked by the information-theoretic approach (modified Akaike’s information criterion). The study stressed the importance of mixed woods for wild boar and the usefulness of hunting data as a mean to predict the habitat suitability for the species.     

Density-dependent parameters and demographic equilibrium in open populations

Populations near their equilibrium are expected to show density-dependence through a negative feedback on at least one demographic parameter, e.g. survival and/or productivity. Nevertheless, it is not always clear which vital rate is affected the most, and even less whether this dependence holds in open populations in which immigration and emigration are also important. We assessed the relative importance of population density in the variation of local survival, recruitment, proportion of transients (emigrants) and productivity through the analysis of detailed life-histories of 4286  seabirds from a colony that reached an apparent demographic equilibrium after a period of exponential increase. We provide evidence that the role of population density and resource availability changes according to the demographic parameter considered. Estimates indicated that transients increased from 5% to 20% over the study period, suggesting an average turnover of about 1400 individuals per year. The parameters most influenced by population density alone were local survival and probability of transience. Recruitment was negatively associated with population density during the increasing phase but unexpected high values were also recorded at high population levels. These high values were explained by a combination of population size and food availability. Mean productivity varied with food availability, independently from population variations. The population density alone explained up to a third of the yearly variation of the vital rates considered, suggesting that open populations are equally influenced by stochastic and density-independent events (such as environmental perturbations) than by intrinsic (i.e. density-dependent) factors.     

Habitat and reproductive phenology of wild boar (Sus scrofa) in the western Iberian Peninsula

We examined the reproductive phenology of wild boar populations in four regions of the western Iberian Peninsula during the 1999/2000 hunting season (October–February). To estimate conception dates and birth distribution frequencies, we used foetal weights. Regions differed significantly, and we detected a relationship between region and birth distribution frequencies. Throughout the year, food availability had a major influence on the distribution of farrowing. Although a short period of high food availability leads to highly synchronous births, even in relatively harsh environmental conditions, adult females that exploit low-quality food items appear to be able to give birth at any time of the year.     

Reproductive allocation in pulsed-resource environments: a comparative study in two populations of wild boar

Pulsed resources influence the demography and evolution of consumer populations and, by cascading effect, the dynamics of the entire community. Mast seeding provides a case study for exploring the evolution of life history traits of consumers in fluctuating environments. Wild boar (Sus scrofa) population dynamics is related to seed availability (acorns/beechnuts). From a long-term monitoring of two populations subjected to markedly different environmental contexts (i.e., both low vs. high frequency of pulsed resources and low vs. high hunting pressure in Italy and in France, respectively), we assessed how pulsed resources shape the reproductive output of females. Using path analyses, we showed that in both populations, abundant seed availability increases body mass and both the absolute and the relative (to body mass) allocation to reproduction through higher fertility. In the Italian population, females equally relied on past and current resources for reproduction and ranked at an intermediate position along the capital-income continuum of breeding tactics. In contrast, in the French population, females relied on current more than past resources and ranked closer to the income end of the continuum. In the French population, one-year old females born in acorn-mast years were heavier and had larger litter size than females born in beechnut-mast years. In addition to the quantity, the type of resources (acorns/beechnuts) has to be accounted for to assess reliably how females allocate resources to reproduction. Our findings highlight a high plasticity in breeding tactics in wild boar females and provide new insight on allocation strategies in fluctuating environments.     

Craniometrical analysis of Bulgarian wild boar (Sus scrofa) populations

Skull characters of wild boars ( Sus scrofa L.) from four regions of Bulgaria were compared using stepwise discriminant, cluster of cases and principal component analyses (PCA). Classification functions were derived for discriminating individuals from different areas. Specimens from the north-eastern part of the country (Dobrudja and the Balkan Range) were found well separated from those from the south (Rila-Rhodopes & Strandja Mountains). PCA showed the differences being mostly related to the size rather than to the shape of both the cranium and the mandible. Natural migrations, intergradation areas between different subspecies, as well as restocking and hybridization with semi-domestic pigs are discussed as possible factors influencing the solution of the problem of the intraspecific systematics of the wild boar in Bulgaria.     

Reproductive parameters of wild female Rhinopithecus roxellana

On the basis on 6 years of observation, we estimated the reproductive parameters of a Golden snub-nosed monkey (Rhinopithecus roxellana) group in the Qinling Mountains, China. We observed 88 births in 47 females from 2001 to 2006. Two methods were used to calculate the birthrate. The first method is based on the number of births observed in a year, giving 0.49+/-0.07 (mean+/-SD), and the second method is based on the female-years of observation, giving 0.49+/-0.17 births per female per year in this troop. The mean interbirth interval is 21.88+/-6.01 months (mean+/-SD). The mortality of infant born between 2002 and 2005 was 22.4%. The interbirth intervals of females that had lost an infant before the age of 6 months were significantly shorter than that of females whose infants survived for more than 6 months. A female usually gives birth once every 2 years if the previous offspring survives to a weaning age of 5-6 months, or will give birth in the next year if the previous young dies before reaching an age of 6 months. Births were significantly concentrated during March to May of each year. The mean birth date was on April 14, median was April 12; and the standard deviation was 13.98 days. Birth peak occurs 6-7 months after mating peak. From observations on 15 individuals that gave birth for the first time, we concluded that the wild female Golden snub-nosed monkeys in Qinling Mountains start giving birth at an age of 5 or 6 years. We suggest that the seasonal reproductive pattern is an adaptive response to the availability of seasonal food. Our results are consistent with the hypothesis that these reproductive characteristics are a result of adaptation to the seasonality of mountain climate and food resources.     

Spatial familial networks to infer demographic structure of wild populations

1. In social species, reproductive success and rates of dispersal vary among individuals resulting in spatially structured populations. Network analyses of familial relationships may provide insights on how these parameters influence population‐level demographic patterns. These methods, however, have rarely been applied to genetically derived pedigree data from wild populations.
2. Here, we use parent–offspring relationships to construct familial networks from polygamous boreal woodland caribou (Rangifer tarandus caribou) in Saskatchewan, Canada, to inform recovery efforts. We collected samples from 933 individuals at 15 variable microsatellite loci along with caribou‐specific primers for sex identification. Using network measures, we assess the contribution of individual caribou to the population with several centrality measures and then determine which measures are best suited to inform on the population demographic structure. We investigate the centrality of individuals from eighteen different local areas, along with the entire population.
3. We found substantial differences in centrality of individuals in different local areas, that in turn contributed differently to the full network, highlighting the importance of analyzing networks at different scales. The full network revealed that boreal caribou in Saskatchewan form a complex, interconnected familial network, as the removal of edges with high betweenness did not result in distinct subgroups. Alpha, betweenness, and eccentricity centrality were the most informative measures to characterize the population demographic structure and for spatially identifying areas of highest fitness levels and family cohesion across the range. We found varied levels of dispersal, fitness, and cohesion in family groups.
4. Synthesis and applications: Our results demonstrate the value of different network measures in assessing genetically derived familial networks. The spatial application of the familial networks identified individuals presenting different fitness levels, short‐ and long‐distance dispersing ability across the range in support of population monitoring and recovery efforts.

     

Seroepidemiologic survey for Chlamydia suis in wild boar (Sus scrofa) populations in Italy

We used serology to estimate the prevalence of exposure to chlamydiae in Italian populations of wild boars (Sus scrofa). Sera from 173 hunter-killed wild boars harvested during the 2006-2009 hunting seasons in three Italian regions were tested for antibodies to Chlamydia suis, Chlamydophila pecorum, Chlamydophila abortus, and Chlamydophila psittaci by the microimmunofluorescence test. Antibody titers to chlamydiae ≥ 1:32 were detected in 110 of the 173 samples tested (63.6%). Specific reactivity could be assessed only in 44 sera with antibody titers to C. suis that were two- to threefold higher than antibody titers against the other chlamydial species; the other 66 sera had similar reactivity against all the chlamydia species tested. Antibody to C. suis was detected in sera from wild boar populations with rare or no known contact with domestic pigs. These results suggest that the wild boar could be a chlamydia reservoir and may acquire chlamydiae independent of contacts with the domestic pig.     

The genetic impact of demographic decline and reintroduction in the wild boar (Sus scrofa): a microsatellite analysis

The reintroduction of wild boar from central Europe after World War II has contributed substantially to the range expansion of this species in Italy, where indiscriminate hunting in earlier times resulted in extreme demographic reduction. However, the genetic impact of such processes is not well-understood. In this study, 105 individuals from Italian and Hungarian wild boar populations were characterized for nine autosomal microsatellite loci. The Hungarian samples, and two central Italian samples from protected areas (parks) where reintroduction is not documented, were assumed to be representative of the genetic composition of the source and the target populations in the reintroduction process, respectively. Animals hunted in the wild in the Florence area of Tuscany (Italy) were then studied to identify the effects of reintroduction. The results we obtained can be summarized as follows: (i) none of the populations analysed shows genetic evidence of demographic decline; (ii) the three parental populations from Italy and Hungary are genetically distinct; however, the low level of divergence appears in conflict with the naming of the Italian and the European subspecies (Sus scrofa majori and Sus scrofa scrofa, respectively); in addition, the Italian groups appear to be as divergent from each other as they are from the Hungarian population; (iii) most of the individuals hunted near Florence are genetically intermediate between the parental groups, suggesting that hybridization has occurred in this area, the average introgression of Hungarian genotypes is 13%, but approximately 45% of the genetic pool of these individuals can not be directly attributed to any of the parental populations we analysed; (iv) analysis of microsatellite loci, though in a limited number, is an important tool for estimating the genetic effect of reintroduction in the wild boar, and therefore for the development of conservation and management strategies for this species.     

Potential ecological and epidemiological factors affecting the persistence of classical swine fever in wild boar Sus scrofa populations

• 1 Classical swine fever has increased in economic importance since it has become endemic in some wild boar Sus scrofa populations in Europe. The mechanism of disease persistence is still not well understood, and several aspects of both the ecology of boar and the virus are claimed to be responsible for disease persistence.
• 2 We review literature on the spread and persistence of the disease in free‐ranging wild boar. We determine whether the available knowledge can explain the observed patterns via mechanistic processes and their interactions, and assemble knowledge in a conceptual model.
• 3 We speculate that the most important factor explaining disease persistence is an alteration in disease outcome, resulting in individual courses with prolonged infectiousness or a sustained reproductive population through immunity. This effect is reinforced by high wild boar numbers either within sites or scattered over larger areas.
• 4 We highlight the sparse knowledge of disease transmission between wild boar. We derive management suggestions for different phases of an outbreak based on the conceptual model and advocate the use of model‐based investigations to test alternative management options.

     

Reproductive asynchrony and population divergence between two tropical bird populations

High-latitude vertebrates generally breed seasonally and synchronouslyas the primary environmental cue used to time seasonal processesis photoperiod. Investigations of tropical vertebrates havealso documented seasonal reproduction, but it is unclear howsynchronous reproduction is, both within and between populations.In this study, we investigated whether seasonal reproductionin a tropical species is synchronous between two populationsin close proximity and, if not, whether asynchrony is correlatedwith genetic and cultural differentiation. We describe two equatorialpopulations of rufous-collared sparrows (Zonotrichia capensis),at the same latitude and separated by 25 km, that each breedseasonally but out of phase with each other. This asynchronousreproductive phenology is associated with local weather patternsand is independent of photoperiod. At a finer scale, reproductivetiming is more highly synchronized within monogamous pairs thanwithin the population as a whole. Associated with the differencein reproductive phenologies, we document that males in eachpopulation sing different song dialects. Using microsatelliteDNA analysis, we found limited gene flow and significant geneticdifferentiation between the two populations. From these resultswe hypothesize that cultural and genetic differentiation betweenpopulations, which can be greater in tropical populations thantemperate ones, can be associated with locally adapted reproductivephenologies.     

Sensitivity analysis of effective population size to demographic parameters in house sparrow populations

The ratio between the effective and the census population size, , is an important measure of the long‐term viability and sustainability of a population. Understanding which demographic processes that affect most will improve our understanding of how genetic drift and the probability of fixation of alleles is affected by demography. This knowledge may also be of vital importance in management of endangered populations and species. Here, we use data from 13 natural populations of house sparrow (Passer domesticus) in Norway to calculate the demographic parameters that determine . Using the global variance‐based Sobol’ method for the sensitivity analyses, we found that was most sensitive to demographic variance, especially among older individuals. Furthermore, the individual reproductive values (that determine the demographic variance) were most sensitive to variation in fecundity. Our results draw attention to the applicability of sensitivity analyses in population management and conservation. For population management aiming to reduce the loss of genetic variation, a sensitivity analysis may indicate the demographic parameters towards which resources should be focused. The result of such an analysis may depend on the life history and mating system of the population or species under consideration, because the vital rates and sex–age classes that is most sensitive to may change accordingly.     

Mitochondrial DNA sequence variation and phylogenetic relationships among Iberian pigs and other domestic and wild pig populations

Nucleotide sequences of mitochondrial DNA (mtDNA) cytochrome B gene (1140 bp) and control region (707 bp) were used to determine the phylogenetic relationships among 51 pig samples representing ancient and current varieties of Iberian pigs (26), Spanish wild boars (seven) and other domestic pigs (18) of cosmopolitan (Duroc, Large White, Landrace, Pietrain and Meishan) and local (Spotted Black Jabugo, Basque and Mangalitza) breeds. A neighbour-joining tree constructed from pairwise distances provide evidence of the European origin of both Iberian pigs and Spanish wild boars. The introgression of Asian mtDNA haplotypes in the genetic pool of the Iberian breed seems unlikely. Four estimates of sequence divergence between European and Asian clades were calculated from the two main domains of the D-loop region and the synonymous and nonsynonymous nucleotide substitutions in the cytochrome B gene. The time since the divergence of pig ancestors was estimated at about 600,000 years before present.     

Reproductive ecology and genetic variability in natural populations of the wild potato,Solanum kurtzianum

The cultivated potato (Solanum tuberosum ssp. tuberosum) has more than 200 related wild species distributed along the Andes, adapted to a wide range of geographical and ecological areas. Since the last century, several collection expeditions were carried out to incorporate genetic variability into the potato germplasm around the world. However, little is known about the reproductive ecology and genetic population structure of natural potato population from field studies. The aim of this work is to study, in the field, the genetic variability and reproductive strategies of populations of one of the most widely distributed potato species in Argentina, Solanum kurtzianum, growing in Mendoza province. AFLP markers showed that the genetic variability is mainly present among plants within populations, indicating that in the sampled populations, sexual reproduction is more relevant than clonal multiplication (by tubers). Additional evidence was obtained evaluating the genetic diversity in populations with a distribution in patches, where several genotypes were always detected. From a field study performed in the Villavicencio Natural Reserve, we found that the average number of plump seeds per fruit was 94.3, identified and calculated the foraging distance of four insect pollinators, and demonstrated the seed dispersal by storm water channels. We argue that the breeding system, the two modes of reproduction and the ecological interaction described here may have a prominent role in determining the genetic structure of S. kurtzianum populations, and discuss the importance of field studies on population genetics, reproductive biology and ecology to design collections and conservation strategies.