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1.
Sonia Saïd Vincent Tolon Serge Brandt Eric Baubet 《European Journal of Wildlife Research》2012,58(1):107-115
Spatial variation of the ‘predation risk’ due to human activities or distribution may increase the sexual difference in habitat
selection. Indeed, females with offspring are usually more risk adverse than males. Based on a long-term wild boar study,
we analysed the diurnal distribution of female and male wild boar before, during and after the hunting period. Hunting, food
and foliation were investigated as factors affecting patterns of forest parcel selection. As expected, dense vegetative covers
were selected during resting periods, but wild boar decreased this pattern of habitat selection in response to hunting disturbance.
Moreover, the habitat selection of wild boar did not fit with the variation of food availability (presence or absence of mast)
and the vegetation cycle. As expected, sows responded more to the hunting disturbance than males, leading to a more pronounced
sexual difference during the riskier season. The unexpected decrease of bush use may be explained either by the increased
hunting effort in this habitat or by the increased movements between resting sites due to disturbance, leading to a more random
habitat selection pattern. The observed difference between sexes could result from a higher response of females with offspring
to hunting, leading to an increased frequentation of secondary habitats, whereas males can tolerate more risks and remain
hidden in thicket plots. Our results highlight how hunting disturbance can lead game species to change their patterns of refuge
habitat selection and may affect the habitat segregation between the sexes. 相似文献
2.
Identifying key habitats for the conservation of Bonelli's Eagle Aquila fasciata using radiotracking 下载免费PDF全文
Identifying the priority habitats of endangered species is crucial to implementing effective conservation actions. We characterize the key habitats used by Bonelli's Eagle Aquila fasciata, an umbrella and flagship species that is endangered in Mediterranean countries. We radiotracked 17 breeding individuals (10 males and seven females) in Catalonia (NE Iberian Peninsula) and used compositional analysis to determine the key habitats in home‐ranges of both sexes. The main habitats identified within the home‐range area were scrubland, coniferous forests, cropland, sclerophyllous forests, rock outcrops and urban areas, with little difference in habitat use between the sexes. Bonelli's Eagles preferred rocky habitats as breeding areas and scrubland as foraging areas, as these hold the highest abundance of their main prey, Rabbits Oryctolagus cuniculus and Red‐legged Partridges Alectoris rufa. Habitat selection varied seasonally in foraging areas: scrubland was the most preferred habitat type during the breeding season, whereas rocky areas were preferred during the non‐breeding season (although scrubland was also highly selected). Urban areas were avoided both as breeding and as foraging areas. Home‐range size was inversely correlated with the proportion of scrubland, suggesting that this is a key habitat for Bonelli's Eagle. To conserve this species effectively, policies that ensure the preservation of the cliffs used as breeding sites, as well as suitable management of the scrubland used for foraging, should be implemented in the areas inhabited by this species. The promotion of traditional land uses and management techniques that will enhance open areas in Mediterranean landscapes should in the future play an essential role in the conservation of Bonelli's Eagle in Mediterranean habitats. 相似文献
3.
Anja B. Riber 《Acta theriologica》2006,51(4):363-371
HedgehogsErinaceus europaeus Linnaeus, 1758 were radio-tagged and monitored during the summer of 2001 in a Danish rural area with the objective of quantifying
home ranges, nightly distances travelled, habitat use, activity patterns, day-nesting habits, and body-weight changes of the
five males and five females being recorded. Males had larger home-range sizes and travelled longer nightly distances than
females. The two most common habitat types within the home ranges of the hedgehogs were deciduous forest and arable land,
whereas the two most frequently used habitat types were deciduous forest and grassland. No differences between the sexes were
found in the proportions of different habitat types within the home ranges or in habitat use. Non-random habitat use was found;
forested areas and edge habitats seemed preferred to open areas. The most frequently used day-nesting habitat was deciduous
forest. Foraging was by far the most time-consuming nightly activity for both sexes. Males lost weight during the study period
(May–July), whereas females gained weight. A peak in the frequency of sexual behaviour was found from late-June to mid-July.
The high level of male ranging activity and the weight loss of males are interpreted as a consequence of the promiscuous mating
system of hedgehogs. 相似文献
4.
In forest fragments, rare habitats contribute to heterogeneity and may provide unique resources for frugivorous species like peccaries with spatially and temporally complex patterns of range use. This study examined seasonal habitat use by two sympatric peccary species ( Tayassu pecari and Tayassu tajacu ) in an Atlantic forest fragment on the plateau region of São Paulo state, Brazil. Previous studies showed that range use by T. pecari was highly nonrandom, and that both species persisted at population densities typical of larger forest fragments. To explain this, we quantified the use and availability of habitats and riparian zones with compositional analysis. Use by T. pecari was nonrandom with respect to availability. Habitat preferences were different during dry and wet seasons and corresponded closely with seasonal movements, core range and fruit use. Although aquatic habitats made up a small proportion of the herd home range, they were most preferred by T. pecari during both seasons. Headwater palmito Euterpe edulis swamps were most favored in the dry season, whereas swamps and marshes near larger streams were preferred in the wet season. Tayassu pecari preferred riparian zones <50 m from streams over drier zones. These habitats were important sources of fruits, travel routes and corridors between forest patches in the agricultural matrix. The least-preferred habitat of T. pecari during both seasons was disturbed forest edge dominated by bamboo. Habitat and riparian zone use were herd-specific for T. tajacu and related to habitat quality and composition where stable home ranges had been established. The persistence of viable peccary populations after 75 years of fragmentation-associated pressures is related to preservation of rare habitats and overall habitat diversity. Thus, T. pecari is an indicator of high habitat diversity in forest fragments and will function as an umbrella species when targeted for conservation. 相似文献
5.
Joseph Soltis 《Primates; journal of primatology》1999,40(3):453-467
Heterosexual relationships during one mating season were examined in a wild troop of Japanese macaques (Macaca fuscata yakui) on Yakushima Island, Japan. Validation tests of putative mate choice behaviors demonstrated that female initiation and maintenance
of proximity, female lookback at the male, and sexual presents to the male, were associated with increased mating. Male grooming
the female was also associated with increased mating. Ten dyadic social behaviors were subject to principal components analysis
to empirically define behavioral dimensions of male-female relationships. The analysis yielded four relationship dimensions:
‘Mutual Choice and Male Coercion,’ ‘Female Choice’ (two types), and ‘Mutual Choice’ Dyads tended to be characterized by more
than one dimension. The results suggested that females sought matings with multiple males of various dominance ranks. Female
relationships with high ranking males contained elements of male coercion and mate guarding, however, because these males
attempted to inhibit females from mating with lower ranking males. The correlation between each relationship dimension and
mating success depended, in part, on the dominance rank of males. Relationships involving high ranking males, which were most
likely to contain elements of male coercion and mate guarding, were associated with mating success. Relationships involving
low ranking males, which usually lacked such coercive elements. were less strongly correlated with mating success. These results,
obtained from a wild troop, are compared to those previously obtained in captive and provisioned groups of Japanese macaques. 相似文献
6.
Many sexually dimorphic mammals show sexual segregation of habitat use. We studied habitat selection and use by male and female elephants in the Okavango Delta, and males of different ages and therefore sizes, to assess whether size was a driving force behind any sex differences in habitat selectivity. There was variation in habitat choices, with males preferring island vegetation and mopane woodland and avoiding grassland/floodplain and Terminalia woodland; females showed no selection for or against most habitats other than selecting for mopane woodland in the rainy season. Male habitat choice changed dramatically during the dry season, when resources were most limited and there was the least sexual difference in habitat selection. Females were more selective in the flood season, when access to resources was restricted. Contrary to other studies and the forage selection hypothesis, males showed greater habitat selectivity than females, but age, and therefore size, did not affect their habitat selection. Whilst our data suggested that males were superior competitors, we could not discount that females excluded males from preferred habitats. In the Okavango Delta, habitat selection by male elephants may be more dependent on social groupings, and hence the decisions of others, than individual size and energetic requirements. 相似文献
7.
Mating habits of the rockfishSebastes inermis 总被引:1,自引:1,他引:0
Synopsis Underwater observations were conducted on the mating habits of rockfish,Sebastes inermis, southwest of Kyushu Island, Japan, in 1984–1986. The reproductive season of the fish lasted from October to January, when
most males over 1 year of age established territories ranging from 12 to 70 m2. Home ranges of females overlapped with male territories. Males performed courtship behaviors when females approached the
territories. Principal motor patterns of courtship were characterized by ‘lateral display’ and ‘rushing and turning’ movements.
The mating pair formed about 30 min before copulation. As the mating pair ascended to 1.5–2.0 m above the bottom, the male
suddenly coiled around the female's body to copulate. In spite of frequent courtship behavior [14.8 (±10.7 SD)×15 min−1, December 1985] of males, only seven copulations were observed, occurring mostly at dusk in December. In December and January,
more than half of the males had accumulated urine, some large volume of it. It was assumed that the male attracted the female
by releasing substances via urine during the ‘lateral display’ movements, which were performed just in front of the female,
near the snout. Other functional aspects of courtship behavior are discussed. 相似文献
8.
JAMES C. BEASLEY TRAVIS L. DEVAULT MONICA I. RETAMOSA OLIN E. RHODES JR. 《The Journal of wildlife management》2007,71(4):1125-1133
Abstract: Although numerous studies have examined habitat use by raccoons (Procyon lotor), information regarding seasonal habitat selection related to resource availability in agricultural landscapes is lacking for this species. Additionally, few studies using radiotelemetry have investigated habitat selection at multiple spatial scales or core-use areas by raccoons. We examined seasonal habitat selection of 55 (31 M, 24 F) adult raccoons at 3 hierarchical orders defined by the movement behavior of this species (second-order home range, second-order core-use area, and third-order home range) in northern Indiana, USA, from May 2003 to June 2005. Using compositional analysis, we assessed whether habitat selection differed from random and ranked habitat types in order of selection during the crop growing period (season 1) and corn maturation period (season 2), which represented substantial shifts in resource availability to raccoons. Habitat rankings differed across hierarchical orders, between seasons within hierarchical orders, and between sexes within seasons; however, seasonal and intersexual patterns of habitat selection were not consistent across hierarchical orders of spatial scale. When nonrandom utilization was detected, both sexes consistently selected forest cover over other available habitats. Seasonal differences in habitat selection were most evident at the core-area scale, where raccoon selection of agricultural lands was highest during the maturation season when corn was available as a direct food source. Habitat use did not differ from availability for either sex in either season at the third-order scale. The selection of forest cover across both seasons and all spatial orders suggested that raccoon distribution and abundance in fragmented landscapes is likely dependent on the availability and distribution of forest cover, or habitats associated with forest (i.e., water), within the landscape. The lack of consistency in habitat selection across hierarchical scales further exemplifies the need to examine multiple biological scales in habitat-selection studies. 相似文献
9.
MHC-associated mating strategies and the importance of overall genetic diversity in an obligate pair-living primate 总被引:1,自引:0,他引:1
Mate choice is one of the most important evolutionary mechanisms. Females can improve their fitness by selectively mating
with certain males. We studied possible genetic benefits in the obligate pair-living fat-tailed dwarf lemur (Cheirogaleus medius) which maintains life-long pair bonds but has an extremely high rate of extra-pair paternity. Possible mechanisms of female
mate choice were investigated by analyzing overall genetic variability (neutral microsatellite marker) as well as a marker
of adaptive significance (major histocompatibility complex, MHC-DRB exon 2). As in human medical studies, MHC-alleles were
grouped to MHC-supertypes based on similarities in their functional important antigen binding sites. The study indicated that
females preferred males both as social and as genetic fathers for their offspring having a higher number of MHC-alleles and
MHC-supertypes, a lower overlap with female’s MHC-supertypes as well as a higher genome wide heterozygosity than randomly
assigned males. Mutual relatedness had no influence on mate choice. Females engaged in extra-pair mating shared a significant
higher number of MHC-supertypes with their social partner than faithful females. As no genetic differences between extra-pair
young (EPY) and intra-pair young (IPY) were found, females might engage in extra-pair mating to ‘correct’ for genetic incompatibility.
Thus, we found evidence that mate choice is predicted in the first place by the ‘good-genes-as-heterozygosity hypothesis’
whereas the occurrence of extra-pair matings supports the ‘dissassortative mating hypothesis’. To the best of our knowledge
this study represents the first investigation of the potential roles of MHC-genes and overall genetic diversity in mate choice
and extra-pair partner selection in a natural, free-living population of non-human primates. 相似文献
10.
Samantha E. Franks Guillermo Fernández David J. Hodkinson T. Kurt Kyser David B. Lank 《PloS one》2013,8(11)
Many bird species show spatial or habitat segregation of the sexes during the non-breeding season. One potential ecological explanation is that differences in bill morphology favour foraging niche specialisation and segregation. Western sandpipers Calidris mauri have pronounced bill size dimorphism, with female bills averaging 15% longer than those of males. The sexes differ in foraging behaviour and exhibit partial latitudinal segregation during the non-breeding season, with males predominant in the north and females in the south. Niche specialisation at a local scale might account for this broad geographic pattern, and we investigated whether longer-billed females and shorter-billed males occupy different foraging niches at 16 sites across the non-breeding range. We used stable-nitrogen (δ15N) isotope analysis of whole blood to test for dietary specialisation according to bill length and sex. Stable-nitrogen isotope ratios increase with trophic level. We predicted that δ15N values would increase with bill length and would be higher for females, which use a greater proportion of foraging behaviour that targets higher-trophic level prey. We used stable-carbon (δ13C) isotope analysis to test for habitat segregation according to bill length and sex. Stable-carbon isotope ratios vary between marine- and freshwater-influenced habitats. We predicted that δ13C values would differ between males and females if the sexes segregate between habitat types. Using a model selection approach, we found little support for a relationship between δ15N and either bill length or sex. There was some indication, however, that more marine δ13C values occur with shorter bill lengths. Our findings provide little evidence that male and female western sandpipers exhibit dietary specialisation as a function of their bill size, but indicate that the sexes may segregate in different habitats according to bill length at some non-breeding sites. Potential ecological factors underlying habitat segregation between sexes include differences in preferred habitat type and predation risk. 相似文献
11.
B. Randrianambinina S. Mbotizafy S. Rasoloharijaona R. O. Ravoahangimalala E. Zimmermann 《International journal of primatology》2007,28(4):783-790
Sportive lemurs are threatened species in the IUCN Red Data Book. However, quantitative information on their reproduction,
urgently required for conservation, has been lacking. We collected first data on reproductive activity of Milne-Edwards’ sportive
lemurs in a population inhabiting the dry deciduous forest of the Ankarafantsika National Park in northwestern Madagascar
during 1998, 2001, and 2003. The species showed a seasonal reproduction. The main mating season extended from May to June,
as indicated by the presence of males with high testes volumes and estrus females. In the mating and early postmating season
and in the postparturition season, sexes did not differ in body mass. Females had a significantly higher body mass than males
in August and November, indicating pregnancy, which together with the presence of small infants in October and November implies
that gravidity in females lasted for about 4–5 mo. All litters consisted of singletons. Individuals with body mass at the
lower limit of the population either did not develop measurable testes volumes (males) or were not in estrus (females). They
were probably juveniles from the previous birth season that achieved sexual maturity not before their second year after birth.
The first data on reproduction suggest a low reproduction rate for Lepilemur edwardsi and a request for a higher conservation status than previously attributed and the need for further management strategies. 相似文献
12.
Clara B. Jones 《Primates; journal of primatology》1985,26(2):130-142
The present study was undertaken to evaluate non-random mating patterns in two groups of mantled howler monkeys in two tropical
dry forest habitats. Sexual dimorphism, female estrus stage, male dominance rank, sexual solicitations and copulations were
assessed. Males are significantly larger than females, but female weight varies more than male weight. The length of female
estrus cycles is comparable in both habitats, but females in the more strongly seasonal habitat demonstrate greater estrus
synchrony relative to their numbers. Males solicit potential mates more frequently than females, a pattern explained by the
relatively high rate of sexual solicitation by high-ranking males. Females in “peak” estrus solicit “alpha” males, while females
in other stages of estrus solicit males equally by rank. Intersexual aggression occurs rarely, and “forced copulations” are
attempted but, apparently, are unsuccessful. Sexual solicitations by “alpha” males and “peak” estrus females are most likely
to lead to copulation, and “alpha” males are more likely to copulate than “gamma” males. In general, latencies from first
solicitation to copulation are expensive in time, especially for high-ranking males. Estimated annual reproduction success
favors high-ranking males, and results indicate that male and female mating behavior is mutually coordinated and controlled. 相似文献
13.
Brian W. Morse Nathan P. Nibbelink David A. Osborn Karl V. Miller 《European Journal of Wildlife Research》2009,55(4):325-332
A better understanding of habitat use and home range size for an exotic fallow deer (Dama dama L.) population in coastal Georgia is needed to understand the relationship between this introduced species and the barrier
island ecosystem. These spatial requirements will aid in management decisions to limit negative impacts to the deer or sensitive
habitats. We describe annual and seasonal home range and habitat use of seven fallow deer fitted with GPS collars. Home ranges
of females averaged 130.3 ± 0.45 ha based on a 95% local convex hull (LoCoH) nonparametric kernel method. Home ranges of adult
males were highly variable, ranging from 56.9 to 354.8 ha. We examined site fidelity by analyzing shifts in core areas and
percent overlap across seasons. Only one individual exhibited a seasonal range shift; all other deer demonstrated a high level
of site fidelity. Based on compositional analysis of habitat use versus availability, fallow deer avoided salt marshes but
showed individual variation in selection of other habitats. Maritime shrub was the most commonly preferred habitat type on
the barrier island. Fallow deer have adapted to effectively use available habitats on the barrier island and have successfully
excluded native white-tailed deer from recolonizing LSSI. 相似文献
14.
Satoshi Awata Saori Miura Satoko Seki Teppei Sagawa Noriyosi Sato Kazuhiko Sakai 《Ichthyological Research》2010,57(2):161-168
To investigate seasonal changes in reproductive and physical condition, sexual dimorphism, and mating tactics in the jewelled
blenny Salarias fasciatus, monthly collections were conducted on the fringing reef in northern Okinawa, Japan. Monthly variation in the female gonadosomatic
index suggested that the breeding season of this species is from April to June. The physical condition and hepatosomatic index
of both sexes considerably deteriorated during the course of the breeding season. Such declines may be primarily due to egg
production in females and brood care in males. Males’ elongated anal spines were longer than females’, but no other apparent
sexual dimorphisms were detected, indicating that S. fasciatus exhibits a low degree of sexual dimorphism. Examinations of testes size and the testicular gland area during the estimated
breeding season revealed that the gonadosomatic index values of smaller males did not differ from those of larger males. This
result may differ from other blenny species that exhibit alternative male reproductive tactics. However, patterns of male
testicular glands of S. fasciatus were similar to those of other blennies with alternative tactics, i.e., smaller males had poorly developed testicular glands
compared with larger males. 相似文献
15.
Banks SC Ward SJ Lindenmayer DB Finlayson GR Lawson SJ Taylor AC 《Molecular ecology》2005,14(6):1789-1801
Habitat fragmentation is one of the major contributors to the loss of biodiversity worldwide. However, relatively little is known about its more immediate impacts on within-patch population processes such as social structure and mating systems, whose alteration may play an important role in extinction risk. We investigated the impacts of habitat fragmentation due to the establishment of an exotic softwood plantation on the social kin structure and breeding system of the Australian marsupial carnivore, Antechinus agilis. Restricted dispersal by males in fragmented habitat resulted in elevated relatedness among potential mates in populations in fragments, potentially increasing the risk of inbreeding. Antechinus agilis nests communally in tree hollows; these nests are important points for social contact between males and females in the mating season. In response to elevated relatedness among potential mates in fragmented habitat, A. agilis significantly avoided sharing nests with opposite-sex relatives in large fragment sites (but not in small ones, possibly due to limited nest locations and small population sizes). Because opposite-sex individuals shared nests randomly with respect to relatedness in unfragmented habitat, we interpreted the phenomenon in fragmented habitat as a precursor to inbreeding avoidance via mate choice. Despite evidence that female A. agilis at high inbreeding risk selected relatively unrelated mates, there was no overall increased avoidance of related mates by females in fragmented habitats compared to unfragmented habitats. Simulations indicated that only dispersal, and not nonrandom mating, contributed to inbreeding avoidance in either habitat context. However, habitat fragmentation did influence the mating system in that the degree of multiple paternity was reduced due to the reduction in population sizes and population connectivity. This, in turn, reduced the number of males available to females in the breeding season. This suggests that in addition to the obvious impacts of reduced recruitment, patch recolonization and increased genetic drift, the isolation of populations in habitat patches may cause changes in breeding behaviour that contribute to the negative impacts of habitat fragmentation. 相似文献
16.
Ricardo Rocha Diogo F. Ferreira Adrià López‐Baucells Fábio Z. Farneda João M. B. Carreiras Jorge M. Palmeirim Christoph F. J. Meyer 《Biotropica》2017,49(6):881-890
Understanding the consequences of habitat modification on wildlife communities is central to the development of conservation strategies. However, albeit male and female individuals of numerous species are known to exhibit differences in habitat use, sex‐specific responses to habitat modification remain little explored. Here, we used a landscape‐scale fragmentation experiment to assess, separately for males and females, the effects of fragmentation on the abundance of Carollia perspicillata and Rhinophylla pumilio, two widespread Neotropical frugivorous bats. We predicted that sex‐specific responses would arise from higher energetic requirements from pregnancy and lactation in females. Analyses were conducted independently for each season, and we further investigated the joint responses to local and landscape‐scale metrics of habitat quality, composition, and configuration. Although males and females responded similarly to a fragmentation gradient composed by continuous forest, fragment interiors, edges, and matrix habitats, we found marked differences between sexes in habitat use for at least one of the seasons. Whereas the sex ratio varied little in continuous forest and fragment interiors, females were found to be more abundant than males in edge and matrix habitats. This difference was more prominent in the dry season, the reproductive season of both species. For both species, abundance responses to local‐ and landscape‐scale predictors differed between sexes and again, differences were more pronounced in the dry season. The results suggest considerable sex‐mediated responses to forest disruption and degradation in tropical bats and complement our understanding of the impacts of fragmentation on tropical forest vertebrate communities. 相似文献
17.
Movement activity and habitat use of Carabus ullrichii (Coleoptera: Carabidae): The forest edge as a mating site? 下载免费PDF全文
Some carabid species are not restricted to a single habitat only, but use various types of habitats. In these species, relatively little is known about the utilization of occupied habitats and factors affecting their movement within these habitats. In this study, we focus on the movement activity of ubiquitous Carabus ullrichii during its reproductive period at the border of two types of habitats, a meadow and a forest. We tracked 21 adult individuals using radio telemetry and recorded in total 1,687 position fixes. Movement activity was associated with the type of habitat and specific environmental conditions such as time of the day and air temperature. Both sexes activated preferably at dusk and during the night, although males were most active at temperatures around 15°C, while females showed no preference for temperature. Males were able to walk as fast as females, but they were more associated with forest edge. We assume that the inner edge of the forest could be used as a mating site and after mating males stay there and wait for new females with which to mate, while fertilized females disperse into the surroundings. They moved further into the closed forest where they were likely looking for oviposition sites and food resources to support reproduction. Exclusively females were recorded to visit the meadow at a greater distance from the forest edge and their movements there were almost always direct. 相似文献
18.
In polygynous ungulates, males may achieve fertilization through the use of alternative reproductive tactics (ARTs), discrete phenotypic variations evolved to maximize fitness. ARTs are often associated with different male spatial strategies during the rut, from territoriality to female‐following. Although variation in space use patterns of rutting male ungulates is known to be largely affected by the spatial distribution of females, information on the year‐round habitat selection of alternative reproductive types is scant. Here, we investigate the seasonal variation in habitat choice of a large mammal with ARTs (territoriality and nonterritoriality), the Northern chamois Rupicapra rupicapra. Global Positioning System (GPS) data on 28 adult males were collected between February 2010 and December 2013 in the Gran Paradiso National Park (Italy) and used to fit resource selection functions to explore the ART‐specific use of key topographic features, such as elevation, aspect, and slope, and vegetation phenology expressed as NDVI values. Territorial and nonterritorial chamois profoundly differed in their habitat selection not only during the rutting season. Compared to nonterritorial males, territorial males used lower elevations in summer and autumn, preferred southern slopes in spring and summer, and used steeper areas in summer but not in winter. We found no difference in seasonal selection of NDVI values between males adopting ARTs. Our results suggest that territorial males tend to occupy warmer, lower‐food‐quality habitats in late spring and summer, whereas nonterritorial males are free to follow and exploit vegetation phenology and more favorable temperatures. Different patterns of habitat selection may reflect different trade‐offs between the optimization of energy balances throughout the year and the increase of mating opportunities during the rut in males adopting alternative reproductive tactics. 相似文献
19.
Xu Jiliang Zhang Xiaohui Zhang Zhengwang Zheng Guangmei Ruan Xiangfeng Zhang Keyin Xi Bo 《Frontiers of Biology in China》2006,1(2):174-181
Home range and habitat use of male Reeves’s pheasant (Syrmaticus reevesii) were studied during winter of 2001∼2002 and 2002∼2003 in the Dongzhai National Nature Reserve, Henan Province. Results from
five individuals of Reeves’s pheasant with over 30 relocations, indicated that the average size of home range was 10.03 ±
1.17 hm2 by Minimum Convex Polygon method, 8.60 ± 0.35 hm2 by 90% Harmonic Mean Transformation method, and 9.50 ± 1.90 hm2 by 95% Fixed Kernel method. It was observed that the winter range is smaller than that in the breeding season. The mean core
area of the home range was found to be 1.88 ± 0.37 hm2. Although the habitat composition of the core area varied greatly for individuals, a large part of the habitats used were
composed of confier and broadleaf mixed forests, masson pine forests, fir forests, and shrubs. Habitat use within the study
area was non-random, while habitats within home ranges were randomly used. Habitat use was dictated by tree diameter at breast
height, shrub height and coverage at 2.0 m. The proximity between forests and shrubs were also found to be important in providing
refuge for the birds during winter. Recommendations for conservation management include protecting the existing habitats in
Dongzhai National Nature Reserve, increasing suitable habitat for Reeves’s Pheasant through artificial plantations (e.g. firs),
and restoring some parts of the large shrub area into forests.
__________
Translated from Biodiversity Science, 2005, 13 (5) [译自: 生物多样性, 2005,13(5)] 相似文献
20.
Luciana Ines Oklander Martin M. Kowalewski Daniel Corach 《International journal of primatology》2010,31(5):813-832
Human-induced habitat fragmentation might seriously affect behavioural patterns and the survival of species whose ecological
requirements strongly depend on specific environmental conditions. We compared the genetic structure and dispersal patterns
of 2 populations of Alouatta caraya (Plathyrrhini, Atelidae) to understand how habitat reduction and fragmentation affect gene flow in this species. We sampled
individuals from 7 groups living in continuous forest (CF, n = 46, 22 males and 24 females), and 11 groups that inhabit a fragmented forest (FF, n = 50, 24 males and 26 females). FST values based on 11 microsatellite loci showed a recent genetic differentiation among
groups in the FF. In contrast, the CF showed no differentiation among groups. Further, FST values between sexes, as well as
kinship relationships, also exhibited differences between habitats. In the CF, both males and females disperse, leading to
nondifferentiated groups composed of adults that are not close relatives. Conversely, in the FF, some groups are differentiated,
males disperse more than females, and groups are composed of closely related adult females. Our results suggest that habitat
fragmentation modifies the dispersal patterns of black-and-gold howlers. These differences between habitats may reflect a
reduced gene flow, providing genetic evidence that suggests that habitat fragmentation severely limits the howler’s ability
to disperse. An increasing level of isolation due to uncontrolled deforestation may cause similar loss of genetic diversity
on other arboreal primates, and nonprimates that depend on forest continuity to disperse, reducing their abilities to cope
with environmental changes. 相似文献