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1.
Few long-term examples exist of wildlife population trends in urban environments despite the recent recognition of the importance of biodiversity in cities. Founded in 1896, Griffith Park’s over 1,700 ha in Los Angeles adjacent to Hollywood represent the largest municipal park in California. Through the 1920s, biologists studied the natural area with great interest but in the decades that followed, little fieldwork was conducted here as Los Angeles developed into a megacity surrounding the park. We combined thorough examination of Griffith Park historical field notes and specimen records (1900–1960) with recent field surveys (2011–2012) to determine (1) the extent of urbanization impacts on butterfly extirpation and persistence and (2) how butterfly traits and host plant relationships might be contributing to butterfly species status. Here we document multiple local butterfly extinctions in Griffith Park; 10 species or 18 % of the historically reconstructed community. Many of these species were lost early in the twentieth century, highlighting the importance of the historical record in understanding urban biodiversity patterns and trends. An analysis of larval host plant status and relationships suggests that a primary factor determining butterfly presence or extirpation is the abundance of the larval host plant in the park, in addition to host plant specificity. Despite these extirpations, we also found that the majority (over 80 %) of native butterfly species have persisted including species of conservation interest. While urban parks certainly suffer from surrounding anthropogenic pressure and impacts, this study also demonstrates the potentially high and underappreciated conservation and ecological value of urban parks.  相似文献   

2.
Mediterranean pine forests are often attacked by caterpillars of Thaumetopoea pityocampa (Lep., Thaumetopoidae), one of the most important defoliators in the Mediterranean region causing large economic losses and ecological effects. The needle terpene concentrations and emissions may play a key role in the defense of pines. We studied two subspecies of Pinus sylvestris, nevadensis (an endemic and relict subspecies) and iberica , with different levels of caterpillar attack in Sierra Nevada mountains (Spain). GC–MS analyses showed large total concentrations of terpenes (6 to 39 mg g?1 of dry weight) in the needles of both subspecies under field conditions. Concentrations were 25 % higher in “Non-Attacked Trees” (NATs) of the iberica than in the nevadensis subspecies. The branches of NATs had terpene concentrations 20 % higher than those of “Attacked Branches of attacked trees” (ABs). Within attacked trees, the “Non-Attacked Branches” (NABs) also had terpene concentrations 20 % higher than those of ABs. Mainly α-pinene and germacrene D had higher concentrations in NATs and NABs than in ABs. Some terpenes had higher concentrations in NABs than in NATs, indicating possible systemic reactions. In subsp. nevadensis, the percentage of monoterpenes relative to total terpenes was higher in ABs than in other attack states. The rates of emission in nevadensis (standardized to 30 °C) were ca. three times higher in ABs than in NABs and NATs. These results suggest that the lower terpene concentrations and high percentages of monoterpenes in ABs were produced by a combination of emission losses and terpene induction in response to herbivorous attack.  相似文献   

3.
Orophilous species are often unable to escape the consequences of climate change because mountains are surrounded by unsuitable habitats. Among them, several endemic species belonging to the genus Erebia Dalman (Lepidoptera, Nymphalidae, Satyrinae) can be considered as key species to assess the risk of biodiversity loss of mountain habitats. The aim of this paper is to measure changes that have occurred in the altitudinal distribution of Erebia cassioides on the Pollino Massif (Southern Italy) during the last 37 years. Sixteen sites sampled in 1975 have been resampled after about three decades (2004, 2012). In 1975 56 % of the sampled population inhabited sites above and 44 % sites below the treeline, while in 2004 and 2012 99 % of the population were observed above the treeline. Furthermore, we observed an uphill shift of 180 m in the barycentre altitude of the species distribution and an unexpected increased density of the population above the treeline which led to a range reduction coupled to population increase of E. cassioides. This pattern contrasts with the usually observed one that couples habitat reduction to population decreasing. The reason for the observed pattern is unclear, but the implication for conservation strategies could be important if confirmed for other species. In fact, during coming decades local extinctions as a consequence of climate change might be fewer and more delayed than expected, and relict populations of cold adapted species could be preserved for a longer time span within optimal habitat refugia.  相似文献   

4.
Teinopalpus aureus (Lepidoptera: Papilionidae) is endemic to the mountains of southern China and Vietnam. This butterfly species was the focus of several high profile poaching cases in China and influenced conservation policies in the country because of this attention. In this study we closely monitored 2.25 km2 of the butterfly’s known habitat in Mt. Dayao Nature Reserve, Guangxi Province, China, from 2012 to 2014. A total of 33 magnolia host plants were found in the plot, and 28 individuals were reared from the egg/early larval stage until they pupated or died. We found T. aureus sufficiently difficult to breed and failed to induce oviposition in captivity. In 2015, a public museum was built in Mt. Dayao Nature Reserve to raise conservation awareness of local biodiversity, which specifically featured an exhibition of T. aureus. To investigate whether the museum was effective in increasing local conservation awareness, in 2013, 2015 and 2017, a total of 1022 local residents were interviewed regarding their conservation awareness of the butterfly. Conservation awareness significantly increased with time from 2013 to 2017, but this was also strongly influenced by residence location and respondent age.  相似文献   

5.
Bhutanitis thaidina Blanchard is a rare and endangered species in China. Based on 2 years of field surveys in the town of Houzhenzi on the south slope of Taibai Mountain, this paper presents documented knowledge of this butterfly’s life history and behaviors, and indicates for the first time the reasons this butterfly is endangered in the field. Life tables show that the L1–L3 larval periods experience a high mortality. Natural enemies (mainly spiders and ants) and unfavorable climatic conditions are mainly important threats for the larval stages. Interspecific competition is also a potential threat to B. thaidina. The host plant Aristolochia manshuriensis occurs from 1,755 to 2,280 m. The suitable habitats for B. thaidina are located at open glades with a canopy cover of 0.4–0.6 in the forests. On the basis of the low population density and scarce suitable habitats, we hypothesize that B. thaidina lives in small extinction-prone populations and survives in the isolated patches in the forests on the south slope of Taibai Mountain. The suggested conservation for long-term survival of B. thaidina is the specific habitat management such as cutting shrubs and preserving open glades in dense forest.  相似文献   

6.
Slovenia has one of the most extensive Natura 2000 networks in Europe with 259 SAC’s covering 31.4% of the country. To determine how well does the current network cover the areas of high butterfly diversity and/or aggregation of the butterfly species of conservation concern, the data from the recent survey for a distribution atlas were used. Altogether 99,423 records of 173 species collated after 1979 were used. The data distribution is slightly biased towards SAC’s, with 44.8% of localities within them, most likely due to sparsely sampled urban areas and intensive farmland areas which are found only outside SAC’s. The diversity and distribution of red listed species was evaluated at a 5 × 5 km grid square level. Additionally the importance of the size of the SAC’s was compared to their butterfly species diversity. In general the high diversity areas also hold the largest aggregation of red listed species with core areas concentrated in SW Slovenia. The SAC’s cover majority of areas with high diversity and the distribution of all but one threatened butterfly species. That species is Colias myrmidone, which is now considered extinct in Slovenia with no records after 1993. The most prominent areas with high conservation value in Slovenia not included in the SAC’s network are the Koro?ka region, Gori?ka Brda region, lower Sava River valley and Slovenske Gorice region. The butterfly diversity in small SAC’s is relatively high with increases in size only gradually increasing the species numbers, thus emphasizing the importance and conservation value of small SAC’s for sustaining high butterfly diversity in Slovenia.  相似文献   

7.
The larval distribution of herbivorous insects play an important role in their development and hence future fitness. Here we study larval distribution of the critically endangered Sinai Baton Blue butterfly, Pseudophilotes sinaicus, which feeds exclusively on the buds and flowers of a single host plant, also endangered, the near-endemic Sinai thyme, Thymus decussatus. We studied the larval distribution over 131 plants, recording the size, quality and phenological stage of the plants along with the presence of beneficiaries. Larvae were found on plants with a high number of flowers, a relatively advanced flowering phenology and tending ants. This highlights the importance of the vitality and quality of the host plant to the spatial distribution of the Sinai Baton Blue. Future conservation plans might concentrate on improving the quality and quantity of the host plant in order to increase resources for this narrowly endemic species.  相似文献   

8.
Satyrium favonius ontario: (W. H. Edwards) (Lepidoptera: Lycaenidae) is considered to be a rare butterfly in the northeastern United States. It receives legal protection in the state of Massachusetts as a Species of Special Concern. We studied the ecology and natural history of a colony of S. f. ontario at Great Blue Hills Reservation in Canton, Massachusetts. In addition, we assembled a database of confirmed S. f. ontario occurrences (n?=?362) and used this along with climate and oak abundance data to build a species distribution model for the northeastern portion of the butterfly’s range in the United States. The model predicts that essentially the entirety of southern New England is suitable for the species, and thus its modeled distribution extends well north of all documented colonies/localities. Just two climate variables, precipitation seasonality and minimum temperature of the coldest month, explained 95% of the model and largely determined relative suitability predictions. We make the case that the hairstreak is a canopy-dwelling insect that sporadically makes ground-level visits, and that its assumed regional rarity is due to detection difficulties rather than demographic rarity. While the butterfly may be imperiled and worthy of legal protection in portions of its range, we question the validity of population estimates and necessity of conservation efforts based on ground-level adult sightings, and recommend larval sampling using burlap bands as a more reliable method to census this butterfly. We also discuss the possibility that other Satyrium and more distantly related hairstreaks (e.g., Callophrys hesseli and Parrhasius m-album) may be additional examples of temperate, canopy-based butterflies.  相似文献   

9.
A characteristic butterfly of Asian steppes, Proterebia afra (Fabricius 1787), was studied in its two relic areas of occurrence within the Balkans—the Askion Mts (a single mountain massif in NW Greece) and Dalmatia (karstic inland S Croatia)—together with co-occurring butterfly communities during its early spring adult flight period. P. afra adults tolerate harsh continental conditions prevailing at its localities during its flight. Local densities were higher in the Askion Mts (up to 100 individuals per 50 m walk) than in Dalmatia (up to 30 individuals per 50 m). Within both areas of occurrence, it inhabits dry grasslands subject to intermediate grazing pressure that retains enough dry grass litter but still suppresses shrubs and trees. Hotter slopes are preferred in more northerly Dalmatia than in the more southerly Askion Mts. More co-occurring butterfly species and more Mediterranean species were recorded in the Askion Mts (69 vs 63; 23 vs 12), but more butterfly individuals and higher species’ richness per transect were observed in Dalmatia. In ordination analyses, the main gradients organising the grassland butterfly communities distinguished between grassy plains and rocky slopes containing more woody plants. Given the distribution extents, local densities and present land use conditions, the Balkan P. afra is not currently endangered, but this may swiftly change with grazing abandonment, especially in Dalmatia, and some conservation actions should be considered in the near future.  相似文献   

10.
Numerous termite species have been introduced outside their native ranges by human transport, and some have become invasive. The dampwood termite Zootermopsis nevadensis (Hagen), which is native to western North America, has been introduced to and become established in Kawanishi City, Hyogo Prefecture, Japan. Zootermopsis nevadensis is subdivided into two subspecies based on cuticular hydrocarbon (CHC) phenotypes: Znevadensis nevadensis and Znevadensis nuttingi (Haverty and Thorne). Here, we identified Znevadensis in Japan as hybrids between the two subspecies. Chemical analysis showed the presence of 7,15-dimethylhenicosane and 5,17-dimethylhenicosane in the CHCs of Znevadensis in Japan, corresponding to the CHC phenotype of Znnevadensis. Conversely, all mitochondrial cytochrome c oxidase subunit I sequences of Znevadensis in Japan were identical to sequences from Znnuttingi and hybrids between the two subspecies from a native hybrid zone in California, USA. In addition, phylogenetic analysis showed that Znevadensis in Japan formed a clade with Znnuttingi and hybrids between the two subspecies. Our results show discordance between the chemical and genetic features of Znevadensis in Japan, indicating that individuals of Znevadensis in Japan are hybrids between the two subspecies.  相似文献   

11.
In temperate mountains, fens have been reported as relict habitats subject to geographical fragmentation and broad climatic gradients, but few studies have analyzed the influence of these factors on plant diversity. Here we investigate the effect of isolation on the vegetation diversity of rich fens (Caricion davallianae) in the mountains of the Iberian Peninsula, the distribution limit of these habitats in south-western Europe. We used plot-based vegetation data from the Pyrenees and the Cantabrian mountain range to evaluate their regional species-pool, occurrence of specialists, beta-diversity and the effect of geo-climatic variables on their species-richness and species-composition. We found a lower ratio of rare specialists in the Pyrenees than in the Cantabrian range, but similar estimates in the species pools, total species-richness per plot and beta-diversity. The isolation of the two mountain regions resulted in different species assemblages best predicted by summer precipitation and bedrock types, showing region-based differences in the response of vegetation and plant specialists to the environment. The tighter correlation between local climate and diversity estimates in the Cantabrian range suggests relict character of rich fens in that region, where climatic conditions have restricted local distribution of formerly more widely distributed specialists. Although there is no relevant evidence of vegetation impoverishment in that region, historical isolation has probably resulted in the existence of fragmentary plant communities. We conclude that fen vegetation may experience long-time persistence in climatically sub-optimal mountain refugia, but related plant specialists may be sensitive to climatic changes and subject to the extinction of local populations.  相似文献   

12.
A mountain butterfly species, Parnassius apollo is protected by the CITES convention of Washington and is threatened or extinct in many European massifs. The definition of the ecological factors which can affect its survival, in particular its relations with its larval foodplants, are important to design conservation policies. The larva of P. apollo is oligophagous and feeds on various species of Crassulaceae. The results of observations and experiments on the female laying preferences and on the efficiency of some of these plants for larval development are exposed here. The two species most cited as foodplants in literature, Sedum album and S. maximum, appeared to be the most efficient. Other species, although frequently mentioned, were rejected and another one performed poorly. A comparison with other cases of foodplant specificity in butterflies is presented and the implications of these results for conservation are discussed.  相似文献   

13.
Species face many threats, including accelerated climate change, sea level rise, and conversion and degradation of habitat from human land uses. Vulnerability assessments and prioritization protocols have been proposed to assess these threats, often in combination with information such as species rarity; ecological, evolutionary or economic value; and likelihood of success. Nevertheless, few vulnerability assessments or prioritization protocols simultaneously account for multiple threats or conservation values. We applied a novel vulnerability assessment tool, the Standardized Index of Vulnerability and Value, to assess the conservation priority of 300 species of plants and animals in Florida given projections of climate change, human land-use patterns, and sea level rise by the year 2100. We account for multiple sources of uncertainty and prioritize species under five different systems of value, ranging from a primary emphasis on vulnerability to threats to an emphasis on metrics of conservation value such as phylogenetic distinctiveness. Our results reveal remarkable consistency in the prioritization of species across different conservation value systems. Species of high priority include the Miami blue butterfly (Cyclargus thomasi bethunebakeri), Key tree cactus (Pilosocereus robinii), Florida duskywing butterfly (Ephyriades brunnea floridensis), and Key deer (Odocoileus virginianus clavium). We also identify sources of uncertainty and the types of life history information consistently missing across taxonomic groups. This study characterizes the vulnerabilities to major threats of a broad swath of Florida’s biodiversity and provides a system for prioritizing conservation efforts that is quantitative, flexible, and free from hidden value judgments.  相似文献   

14.
Projections of climate-change scenarios indicate that many Maculinea arion populations will disappear from Europe over the next 50 years. Extinctions will be particularly concentrated around the southern limits of the species?? range, such as the Italian peninsula, except mountain populations, mainly in the Alps. M. arion is a social parasite of Myrmica ants and its survival depends on the presence and abundance of two resources, i.e. (1) a specific larval foodplant and (2) a suitable Myrmica host ant. We collected data on Thymus plants distribution, Myrmica ants abundance, turf height around Myrmica nests, distance between nests and the closest thyme plant (Thymus pulegioides), and vegetation structure at 14 patches of a M. arion fragmented population occurring in the Western Italian Alps (Val Ferret: Aosta). We found that patches with the highest abundance of M. arion had significantly higher foodplant abundance. Among 407 nests belonging to nine Myrmica species, we found M. arion larvae in one Myrmica lonae and in two Myrmica sulcinodis nests. The distribution of M. sulcinodis nests showed the best spatial overlap with Thymus plants. M. sulcinodis was also significantly more abundant on pastures showing high M. arion density, and therefore offered higher adoption probabilities to develop butterfly larvae. On M. arion habitat patches, the mean turf height around Myrmica nests varied from 10.5 to 22.3 cm and best matched the habitat requirements of T. pulegioides. Thus, we suggest that extensive grazing is needed to maintain the two most important resources for M. arion. Moreover, patches where M. arion was abundant included more numerous plant species characteristic of these mountain pastures, as well as higher plant diversity (Shannon index). As a consequence, M. arion represents an umbrella species and a good indicator for the conservation status of mountain grasslands.  相似文献   

15.
Wildlife conservation and management of endangered species requires reliable information on the size and structure of populations. One of the flagship species in European wildlife conservation is the forest-dwelling capercaillie (Tetrao urogallus), where several populations are endangered. In the Bohemian Forest, e.g., the population severely declined 30 years ago with only 100 birds remaining in 1985. Subsequently, breeding and release programs were conducted to supplement the local population. The current distribution and population size, however, remained unknown. With recent habitat changes and increasing recreational activities, a reliable population estimate to inform conservation plans was needed. A team of scientists and volunteers collected fresh capercaillie droppings covering an area of about 120,000 ha. We genotyped ten microsatellite loci to estimate the current population size and to determine the population’s spatial and genetic structure. Population size and density estimators revealed a population size of approximately 500 individuals, which is thus one of the two largest relict populations in the low mountain ranges of temperate Europe. The population clustering revealed gene flow across the entire study area. Several genotypes were documented with multiple recaptures at spatial distances between 10 and 30 km additionally corroborating gene flow across the entire landscape of the study area. Males were more closely related than females on small spatial scales up to 3 km, indicating lower dispersal rates in males. We conclude that the population currently appears to have a viable size and shows unrestricted gene flow across state borders and management units of the entire Bohemian Forest. However, long-term viability of this population requires a transboundary strategy to sustainably protect and monitor this isolated capercaillie population in Central Europe.  相似文献   

16.
Habitat restoration is critical to the conservation of rare species. However, restoration efforts often proceed without knowledge of their effects on these species. We investigated the reproductive response of federally endangered Fender’s blue butterfly (Plebejus icarioides fenderi) to prairie restoration in Willamette Valley, Oregon, USA. In 2009 and 2010, we quantified availability of larval host plant, Kincaid’s lupine (Lupinus oreganus), and butterfly oviposition in three restored areas (1–10 years old) and adjacent intact habitat. Oviposition measures in restored areas reached or exceeded intact habitat (0.1 eggs/leaf of host plant and 12 % of time ovipositing) within five years post-restoration. However, none of the restorations provided an equivalent host plant density to intact areas (55 leaves/m2). The different response time of host plants and butterflies to restoration highlights the importance of monitoring both vegetation and oviposition over an ecologically relevant timescale (at least 10 years). For imperiled species, quantifying reproductive response to restoration is critical for adaptive management and successful conservation of the species which restoration efforts are intended to benefit.  相似文献   

17.
The occurrence pattern of the marsh fritillary was studied within a patch network on the Baltic island Öland, Sweden. Presence/absence was established for potentially suitable habitat patches (n = 158) on calcareous moist grassland and analyzed in a multiple logistic regression model where patch area, patch isolation and nine habitat quality variables were included as explanatory variables. Larval food plant density was positively, and patch isolation negatively, correlated to the presence of Euphydryas aurinia. Area did not contribute to the explanation of the occurrence pattern. Significant interactions between larval food plant density times patch isolation, and larval food plant density times vegetation height, show that with low food plant density the butterfly primarily occurs in patches with a vegetation height of 4–10 cm, within a distance of 250 m from nearest occupied patch. In patches with a high food plant density the butterfly occurs in patches where the vegetation height is higher, 4–16 cm, and the distance to nearest occupied patch can be longer, up to 1.4 km. This study supports earlier findings in other regions, suggesting that a network of adjacent patches with a high food plant density and a vegetation height within the preferred threshold, despite their size, is an apparent conservation goal.  相似文献   

18.
Habitat loss, fragmentation of meadow patches, and global climate change (GCC) threaten plant communities of montane grasslands. We analyzed the genetic structure of the montane herb Geranium sylvaticum L. on a local scale in order to understand the effects of habitat fragmentation and potential GCC impacts on genetic diversity and differentiation. Amplified fragment length polymorphism (AFLP) fingerprinting and cpDNA sequencing was performed for 295 individuals of 15 G. sylvaticum populations spanning the entire distribution range of the species in the Taunus mountain range in Germany. We found patterns of substantial genetic differentiation among populations using 150 polymorphic AFLP markers (mean F ST = 0.105), but no variation in 896 bp of plastid DNA sequences. While populations in the center of their local distribution range were genetically diverse and less differentiated, higher F ST values and reduced genetic variability was revealed for the populations at the low-altitudinal distribution margins. Projections of GCC effects on the distribution of G. sylvaticum in 2050 showed that GCC will likely lead to the extinction of most edge populations. To maintain regional genetic diversity, conservation efforts should focus on the diverse high-altitude populations, although a potential loss of unique variations in genetically differentiated peripheral populations could lower the overall genetic diversity and potentially the long-term viability in the study region. This study documents the usefulness of fine-scale assessments of genetic population structure in combination with niche modeling to reveal priority regions for the effective long-term conservation of populations and their genetic variation under climate change.  相似文献   

19.
The Wood White butterfly Leptidea sinapis, a UK BAP Priority species, is present in a number of Forestry Commission woodlands in the West Midlands and these constitute an important part of the national resource of this butterfly. A joint SITA Trust funded project between the Forestry Commission and Butterfly Conservation (linking with the National Wood White Conservation Project) is researching the use of habitat by Leptidea sinapis within these sites with regard to targeting conservation management. Two aspects of this research are presented: the results of a mark-recapture study and an analysis of egg-laying habitat. Mark-recapture results show considerable movement between areas of concentrations of adults and between egg-laying areas, with males moving further and faster than females. Movements do occur across potential habitat barriers. Egg locations were found by following females and by searching for eggs. The habitat used for egg-laying is extremely variable even within a site. A number of foodplants species are used and habitat ranges from low height foodplants within bare ground to a foodplant height of over 1 m within thick vegetation and scrub. These results are being integrated into an ongoing project to restore Leptidea sinapis habitat within managed Forestry Commission woodlands.  相似文献   

20.
《Phytochemistry》1986,25(6):1309-1313
Flavonoid pigments have been identified in the swallowtail butterfly Eurytides marcellus and its larval foodplant Asimina triloba (Annonaceae). Although quercetin 3-glycoside, quercetin 3-rutinoside and quercetin 3-rutinoside-7-glucoside are present in the plant, only quercetin 3-glucoside is sequestered by the insect. Flavonoids have also been found in 10 out of 27 other papilionid species examined. These were mainly 3- and 7-glycosides of the flavonols quercetin and kaempferol. The sequestration of flavonoids by papilionid butterflies appears to be related both to the phylogeny of the Papilionidae and to the choice of larval foodplants by the various phylogenetic groups.  相似文献   

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