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1.
The Jungle Cat Felis chaus is widespread in India and neighbouring countries but is known by only one historical specimen from Cambodia, Laos or Vietnam (Indochina), widely published as from Vietnam, but in fact from Cambodia. All but two of the recent Indochinese records come from extensive natural lowland habitat dominated by deciduous dipterocarp forest in northeast Cambodia. The species probably occurred more widely in Indochina, largely through additional use of secondary habitats, where hunting pressure is now very heavy. Suggestions of decline in Indochina are corroborated by more conclusive evidence from Thailand. In Indochina, all other small and medium-sized cats are recorded much more frequently than Jungle Cat: closed evergreen forest supports source populations of them, but there is no evidence that Jungle Cat uses extensively such forest. The open forests of northern and eastern Cambodia are highly significant for conserving threatened biodiversity, notably large waterbirds, vultures and ungulates, groups where species formerly widespread across Indochina have contracted in range and declined steeply. These taxa were better collected than small cats and it seems plausible that Jungle Cat showed a similar change. Jungle Cat conservation in Indochina needs extensive habitat retention with intensive anti-poaching activities, because suitable habitat is easily accessible to hunters. The habitat adaptability shown elsewhere by Jungle Cat could allow a much healthier regional conservation status if hunting (including trapping) can be greatly reduced in scrub and agricultural habitats, but changing culturally ingrained hunting practices will take a long time.  相似文献   

2.
The monotypic Stone Partridge Ptilopachus petrosus (Galliformes: Phasianidae), restricted to arid rocky areas of the northern savanna belt including the Sahel on the southern border of the Sahara Desert, is a taxonomic enigma. Historically, it has been grouped with Asian forest partridges (Galloperdix and Bambusicola spp.). However, recent DNA‐based phylogenetic research has suggested that its closest relative is Nahan's Francolin Francolinus nahani, another taxonomically enigmatic African galliform, and a globally threatened, narrow endemic species associated with the interior of remnant primary forests of the eastern equatorial lowlands of the Democratic Republic of the Congo and Uganda. This hypothesis is investigated in greater detail using additional DNA evidence and information on behaviour and vocalizations. Phylogenetic analyses of the combined sequences from three nuclear and four mitochondrial markers (5554 bases for 84 galliform taxa) overwhelmingly support the sister relationship between F. nahani and P. petrosus. They, in turn, are the distantly related sister taxon of the New World quails (Odontophoridae), and are not related to any other Old World galliform.  相似文献   

3.
The gradual increase in reforested areas worldwide, as a strategy for mitigating native forest loss, has stressed the need of assessing their real value as habitat for native species. Forest plantations, particularly those based on native species, could be valuable for conservation purposes, especially in heavily fragmented and disturbed ecosystems. We evaluated the value of a monoculture of a native tree species, the Andean alder (Alnus acuminata), for the conservation of avifauna in the Central Andes region, which is considered a bird species diversity hotspot but also suffers from high anthropogenic disturbance levels. Our results suggest that alder plantations are valuable for conservation from three points of view: (1) they have similar or greater bird species richness and abundance than secondary native forests; (2) low community similarities are found between this type of forest compared to secondary forest stands (with 27 species exclusive to alder plantations); and (3) three near threatened species (Odontophorus hyperythrus, Eriocnemis derbyi, and Cyanolyca viridicyanus). Further, 27 out of the 85 species found at the alder plantations were of least concern but showing decreasing population trends. While forest plantations do not replace native forests, they offer habitat for many bird species, some of them being of conservation concern (i.e., included in an IUCN threat category) or with decreasing populations. Hence establishing native species plantations among native forest remnants – especially in heavily fragmented landscapes – could have a positive effect in the conservation of threatened avifauna.  相似文献   

4.
The phylogenetic relationships, biogeography and classification of, and morpho‐behavioral (M/B) evolution in, gamebirds (Aves: Galliformes) are investigated. In‐group taxa (rooted on representatives of the Anseriformes) include 158 species representing all suprageneric galliform taxa and 65 genera. The characters include 102 M/B attributes and 4452 nucleic acid base pairs from mitochondrial cytochrome b (CYT B), NADH dehydrogenase subunit 2 (ND2), 12S ribosomal DNA (12S) and control region (CR), and nuclear ovomucoid intron G (OVO‐G). Analysis of the combined character data set yielded a single, completely resolved cladogram that had the highest levels of jackknife support, which suggests a need for a revised classification for the phasianine galliforms. Adding 102 M/B characters to the combined CYT B and ND2 partitions (2184 characters) decisively overturns the topology suggested by analysis of the two mtDNA partitions alone, refuting the view that M/B characters should be excluded from phylogenetic analyses because of their relatively small number and putative character state ambiguity. Exclusion of the OVO‐G partition (with > 70% missing data) from the combined data set had no effect on cladistic structure, but slightly lowered jackknife support at several nodes. Exclusion of third positions of codons in an analysis of a CYT B + ND2 partition resulted in a massive loss of resolution and support, and even failed to recover the monophyly of the Galliformes with jackknife support. A combined analysis of putatively less informative, “non‐coding” characters (CYT B/ND2 third position sites + CR +12S + OVO‐G sequences) yielded a highly resolved consensus cladogram congruent with the combined‐evidence cladogram. Traditionally recognized suprageneric galliform taxa emerging in the combined cladogram are: the families Megapodiidae (megapodes), Cracidae (cracids), Numididae (guineafowls), Odontophoridae (New World quails) and Phasianidae (pheasants, pavonines, partridges, quails, francolins, spurfowls and grouse) and the subfamilies Cracinae (curassows, chachalacas and the horned guan), Penelopinae (remaining guans), Pavoninae sensu lato (peafowls, peacock pheasants and argus pheasants), Tetraoninae (grouse) and Phasianinae (pheasants minus Gallus). The monophyly of some traditional groupings (e.g., the perdicinae: partridges/quails/francolins) is rejected decisively, contrasted by the emergence of other unexpected groupings. The most remarkable phylogenetic results are the placement of endemic African galliforms as sisters to geographically far‐distant taxa in Asia and the Americas. Biogeographically, the combined‐data cladogram supports the hypothesis that basal lineages of galliforms diverged prior to the Cretaceous/Tertiary (K‐T) Event and that the subsequent cladogenesis was influenced by the break‐up of Gondwana. The evolution of gamebirds in Africa, Asia and the Americas has a far more complicated historical biogeography than suggested to date. With regard to character evolution: spurs appear to have evolved at least twice within the Galliformes; a relatively large number of tail feathers (≥ 14) at least three times; polygyny at least twice; and sexual dimorphism many times. © The Willi Hennig Society 2006.  相似文献   

5.
We studied the non-marine reptile and amphibian species of the volcanic Comoro archipelago in the Western Indian Ocean, a poorly known island herpetofauna comprising numerous microendemic species of potentially high extinction risk and widespread, non-endemic and often invasive taxa. According to our data, the Comoro islands are inhabited by two amphibian species and at least 28 species of reptiles although ongoing genetic studies and unconfirmed historical records suggest an even higher species diversity. 14 of the 28 currently recognized species of terrestrial reptiles (50%) and the two amphibians are endemic to a single island or to the Comoro archipelago. The majority of species are most abundant at low elevation. However, a few endemic species, like the gekkonid lizards Paroedura sanctijohannis and Phelsuma nigristriata, are more common in or even confined to higher altitudes. We created habitat maps from remotely sensed data in combination with detailed species distribution maps produced using comprehensive data from field surveys between 2000 and 2010, literature, and historical locality records based on specimens in zoological collections. Using these data, we assessed the conservation status of the endemic terrestrial reptiles and amphibians according to the IUCN Red List criteria. Our results show that although little area of natural forest remains on the Comoros, many species are abundant in degraded forest or plantations. Competition and predation by invasive species appears to be the most important threat factor for the endemic herpetofauna, together with habitat degradation and destruction, which further favours invasive species. We propose the status Endangered for three species, Vulnerable for one species, Near Threatened for six species, Least Concern for four and Data Deficient for two species. The endemic subspecies Oplurus cuvieri comorensis is proposed for the status Critically Endangered. Based on the results of this study, seven areas of importance for reptile and amphibian conservation on the Comoros are identified. This study shows how remote sensing data can contribute to increasing accuracy and objectiveness of conservation assessments.  相似文献   

6.
We study how endemic, native and introduced arthropod species richness, abundance, diversity and community composition vary between four different habitat types (native forest, exotic forest of Cryptomeria japonica, semi-natural pasture and intensive pasture) and how arthropod richness and abundance change with increasing distance from the native forest in adjacent habitat types in Santa Maria Island, the Azores. Arthropods were sampled in four 150 m long transects in each habitat type. Arthropods were identified to species level and classified as Azorean endemic, single-island endemic (SIE), native, or introduced. The native forest had the highest values for species richness of Azorean endemics, SIEs and natives; and also had highest values of Azorean endemic diversity (Fisher’s alpha). In contrast, the intensive pasture had the lowest values for endemic and native species richness and diversity, but the highest values of total arthropod abundance and introduced species richness and diversity. Arthropod community composition was significantly different between the four habitat types. In the semi-natural pasture, the number of SIE species decreased with increasing distance from the native forest, and in the exotic forest the abundance of both Azorean endemics and SIEs decreased with increasing distance from the native forest. There is a gradient of decreasing arthropod richness and abundance from the native forest to the intensive pasture. Although this study demonstrates the important role of the native forest in arthropod conservation in the Azores, it also shows that unmanaged exotic forests have provided alternative habitat suitable for some native species of forest specialist arthropods, particularly saproxylic beetles.  相似文献   

7.
Abstract: The greatest concentration of Chinese Galliformes occurs in the Trans-Himalayas. We selected 4 northwestern Yunnan counties (Lijiang, Shangri-la, Deqin, and Weixi) in the Trans-Himalayas to assess the conservation status of 9 gallinaceous forest birds. We developed maps depicting recent forest cover and modeled habitat availability of each gallinaceous forest bird based on 3 factors that restrict its distribution: geographic location, elevation range, and forest coverage. The conservation status of 4 species was inadequate, because <10% of their respective potential habitats were within existing nature reserves. To predict the historic habitats of the species we studied, we also delineated a forest map from the late 1950s. We calculated the loss and fragmentation of potential habitats within the past 40 years as degree of habitat degradation. Our results showed that all 9 species became reduced and fragmented of their potential habitats from the late 1950s to 2002. Assessing habitat degradation and conservation status of wild species could help identify the threatened species with poor protection and degraded habitats, thereby warranting more attention in future conservation strategies. To protect those threatened species, it is urgent that the government should design new nature reserves to fill the conservation gaps, and enlarge and strengthen the management of existing natural reserves to reduce effects of human activities on their habitats.  相似文献   

8.
中国鸡形目鸟类的现状与保护对策   总被引:13,自引:0,他引:13  
鸡形目是一个与人类关系非常密切的鸟类类群 ,其保护工作受到国际自然保护组织的广泛关注。作为世界上鸡形目鸟类资源最为丰富的国家之一 ,我国加强该类群鸟类的保护工作不仅是野生动物资源保护的一个重要组成部分 ,而且对全球生物多样性的保护具有特别重要的意义。本文结合国家林业局“十五”期间将要实施的《全国野生动植物及自然保护区建设工程总体规划》 ,对我国鸡形目鸟类的多样性、特有性和分布特点进行了阐述 ,对该类群的濒危状况和致危因素进行了分析 ,从就地保护、易地保护以及科学研究三个方面介绍了我国在该类群研究与保护方面所取得的成就 ,探讨了目前保护管理工作中所存在的问题并提出了相应的保护对策  相似文献   

9.
Multiple-use protected areas, in which sustainable levels of extractive livelihood activities are permitted, play an increasingly important role in the global protected area estate, and are expected to rise in prevalence. However, we know little about their effectiveness at conserving biodiversity. We surveyed bird and reptile communities in three areas across a forest disturbance gradient resulting from charcoal production and shifting cultivation within a multiple-use protected area in Madagascar’s sub-arid spiny forest. We scored individual species using a Conservation Value Index (CVI; a simple metric based on rarity, threat and distinctiveness), and estimated the total conservation value of each treatment by calculating the sum of frequency-weighted CVI scores across all present species. Bird and reptile community responses to forest disturbance were idiosyncratic. Bird richness was greatest in the moderate-disturbance treatment, but the low-disturbance treatment had the superior conservation value due to higher frequencies of locally-endemic species. Reptile richness was the same in low- and moderate-disturbance treatments, but the conservation value of the latter was greater. The high-disturbance areas had lowest richness and conservation value for both groups. For birds, increasing disturbance levels were accompanied by community turnover from high-value to low-value species, a pattern highlighted by CVI that is masked by assessing species richness alone. Although some endemic species appear to be resilient to degradation, multiple-use protected areas in Madagascar may lose biodiversity since most endemic species are forest-dependent. Stricter protected area models may be more appropriate in areas where much of the high-value biodiversity is sensitive to habitat degradation.  相似文献   

10.
Of the basal clades of extant birds (Neornithes) the 'landfowl' or galliforms (Aves, Galliformes) are the most speciose. Cladistic analysis of more than 100 morphological characters coded at the generic level for most putative galliform genera confirms that the megapodes ('mound builders'; Megapodiidae) are the most basal clade within the order. They are followed successively by the curassows, guans and chachalacas (Cracidae), which comprise the sister-group to all other extant Galliformes (i.e. Phasianoidea). Within this large 'phasianoid' clade, analyses suggest that the guineafowl (Numididae) are the most basal taxon, although monophyly of this 'family' is not strictly supported on the basis of the morphological characters employed. An additional major clade within the phasianoid Galliformes is recovered by this analysis, comprising the traditional groupings of New World quails (Odontophoridae) and Old World quails ('Perdicini'), yet only monophyly of the former is supported unambiguously by morphological characters. Relationships within the remainder of the phasianoid taxa, including the grouse (Tetraonidae), turkeys (i.e. Meleagris / Agriocharus spp.) as well as other 'pavonine' galliforms (i.e. peafowl; Pavo , Afropavo , Rheinardia , Argusianus and Polyplectron spp.) remain largely unresolved on the basis of morphological characters, yet monophyly of the major subdivisions is supported here. Although there are a number of important differences, especially with regard to relationships within the nonquail phasianoids, the results of this morphological phylogenetic (cladistic) analysis are broadly congruent both with traditional classifications and existing molecular hypotheses of galliform phylogenetic relationships.  相似文献   

11.
The impacts of human pressure, habitat changes, and efficiency of conservation measures on the non-passerine bird community were assessed in the Sudanian belt of Burkina Faso. Three regions with increasingly large protected areas and higher conservation status were compared. In each region, natural savanna woodlands were also compared to traditionally cultivated areas. Six groups of diurnal raptors and six groups of other large bird species were counted along 167 5-km transect counts during the dry season. Within savanna woodlands, the only significant and consistent declines from the little disturbed Eastern National Parks to the more populated and exploited Western forest reserves were those of the largest terrestrial game birds (Guinea fowl, Bustard, Ground Hornbill), eagles and vultures, which became virtually extinct in the least protected areas. Although some species groups maintained substantial, if not higher populations in cultivated areas (rollers, non-game terrestrial birds, several raptors), the overall abundance of both raptor and non-raptor species declined markedly (50–65%) from natural savanna woodlands to tree-dotted cultivated and fallow fields. Again large game birds, eagles and vultures were absent from every agricultural areas censused. Yet, all of them were still commonly recorded in the same natural and cultivated areas during surveys I conducted in the same regions from 1968 to 1973. The main factors correlated with large bird extinctions or declines from national parks to mere forest reserves and from natural woodlands to fields were first related to hunting, then to habitat degradation and fragmentation through intensive cattle grazing and wood cutting and extension of cultivated areas.  相似文献   

12.
Diversity is a property of community that can described, characterized, and understood according to the functioning of ecosystems. To study the richness and local abundance and species replacement between habitats around the Zapatosa's wetland complex (El Cesar Department), I carried out four field trips between November of 2006 and October of 2007. A total of 640 sampling hours/man analyzed five habitat types chasmophyte forest, dry forest, riparian forest, palm-grove and tree-lined savanna; with the exception of the palm-grove sampled at its 75%, the others were sampled up to their 80%. I found 847 reptiles that were distributed in 48 species. The group with the highest number of species was Colubridae with 14, followed by Gekkonidae with five. Five endemic species and eight with some conservation threat grade at a national level are reported. The riparian forest was the richest and most abundant habitat with 34 species and 196 individuals. For each habitat, Colubridae had the highest number of species, followed by the families Polychrotidae, Gekkonidae and Teiidae, in that order. The reptile species composition was not different between the tree-lined savanna and the chasmophyte forest, but differed among the tree-lined savanna and the riparian forest, palm-grove and dry forest habitats. The most important differences in the species composition among almost all the habitats were influenced by the species Anolis tropidogaster and Gonatodes albogularis, and the higher occurrence of Stenocercus erythrogaster in the chasmophyte forest. The species replacement had an average value of 50%; the biggest amounts of shared species were the lizards, while the snake Leptodeira septentrionalis was the only one present in all habitat types. The forest grows-among-rocks showed the biggest complementarity and number of unique species compared to the other habitats. The wetland complex provides two thirds of the reptile's species reported until now for the Caribbean region, and more than 80% of those reported for the El Cesar department. This wetland complex seems to behave as a center for low land species concentration as it hosts a high proportion of species from those places.  相似文献   

13.
Aim To examine biogeographical affiliations, habitat‐associated heterogeneity and endemism of avian assemblages in sand forest patches and the savanna‐like mixed woodland matrix. Location Two reserves in the Maputaland Centre of Endemism (MC) on the southern Mozambique Coastal Plain of northern KwaZulu‐Natal, South Africa. Methods Replicated surveys were undertaken in each of the two habitat types in each reserve, providing species abundance data over a full year. Vegetation structure at each of the survey sites was also quantified. Differences between the bird assemblages and the extent to which vegetation structure explained these differences were assessed using multi‐variate techniques. Biogeographical comparisons were based on species presence/absence data and clustering techniques. Results Bird assemblages differed significantly between habitats both within a given reserve and between reserves, and also between reserves for a given habitat. Differences in vegetation structure contributed substantially to differences between the avian assemblages. Of the four species endemic to the MC, three (Neergaard’s sunbird, Rudd’s apalis, and Woodward’s batis) were consistently present in sand forest. The fourth (pink‐throated twinspot) preferred mixed woodland. None of these endemic species was classed as rare. In the biogeographical analysis, both the sand forest and the mixed woodland bird assemblages were most similar to bird assemblages found in the forest biome or the Afromontane forest biome, depending on the biome classification used. Main conclusions The close affinities of sand forest and mixed woodland assemblages to those of the forest biome are most likely due to similarities in vegetation structure of these forests. Bird assemblages differ between the sand forest and mixed woodland habitats both within a given reserve and between reserves, and also between reserves for a given habitat. These differences extend to species endemic to the MC. Thus, conservation of sand forest habitat in a variety of areas is necessary to ensure the long‐term persistence of the biota.  相似文献   

14.
As large nature reserves occupy only a fraction of the earth’s land surface, conservation biologists are critically examining the role of private lands, habitat fragments, and plantations for conservation. This study in a biodiversity hotspot and endemic bird area, the Western Ghats mountains of India, examined the effects of habitat structure, floristics, and adjacent habitats on bird communities in shade-coffee and cardamom plantations and tropical rainforest fragments. Habitat and birds were sampled in 13 sites: six fragments (three relatively isolated and three with canopy connectivity with adjoining shade-coffee plantations and forests), six plantations differing in canopy tree species composition (five coffee and one cardamom), and one undisturbed primary rainforest control site in the Anamalai hills. Around 3300 detections of 6000 individual birds belonging to 106 species were obtained. The coffee plantations were poorer than rainforest in rainforest bird species, particularly endemic species, but the rustic cardamom plantation with diverse, native rainforest shade trees, had bird species richness and abundance comparable to primary rainforest. Plantations and fragments that adjoined habitats providing greater tree canopy connectivity supported more rainforest and fewer open-forest bird species and individuals than sites that lacked such connectivity. These effects were mediated by strong positive effects of vegetation structure, particularly woody plant variables, cane, and bamboo, on bird community structure. Bird community composition was however positively correlated only to floristic (tree species) composition of sites. The maintenance or restoration of habitat structure and (shade) tree species composition in shade-coffee and cardamom plantations and rainforest fragments can aid in rainforest bird conservation in the regional landscape.  相似文献   

15.

Background  

The Galliformes is a well-known and widely distributed Order in Aves. The phylogenetic relationships of galliform birds, especially the turkeys, grouse, chickens, quails, and pheasants, have been studied intensively, likely because of their close association with humans. Despite extensive studies, convergent morphological evolution and rapid radiation have resulted in conflicting hypotheses of phylogenetic relationships. Many internal nodes have remained ambiguous.  相似文献   

16.
Despite Angola’s central scarp forests being recognised as a critical global priority for bird conservation, fine-scale information on threatened bird distributions and patterns of bird diversity are lacking. These data are essential to identify sites within the Western Angola Endemic Bird Area that should be targeted for conservation. First endemic and near-endemic species and subspecies, and species with isolated populations along the Angolan scarp were identified to highlight taxa of greatest priority for conservation and for use in studying the evolutionary origins of the region. Thereafter survey data collected during 2005 from 13 forest sites along the central scarp was analysed. These data show that there are three distinct bird communities across the width of the escarpment, each associated with a distinctive forest type. Of note is the finding that threatened and Near Threatened endemic species occur almost exclusively in the dry forests adjacent to the main escarpment, rather than in the moistest forests found on the main escarpment, which instead are richer in Congo Basin forest birds. Based on these data, summaries of ranges, populations and conservation threats are given for the seven most threatened bird species. Attention is drawn to threats to the habitats of greatest importance to these species. A conservation area network should be established that encompasses the full spectrum of bird diversity described, to ensure survival of current unique taxa and the future evolutionary potential of the area.  相似文献   

17.
Concomitant with the rapid loss of tropical mature forests, the relative abundance of secondary forests is increasing steadily and the latter are therefore of growing interest for conservation. We analysed species richness of fruit-feeding nymphalid butterflies in secondary forest fragments of different age and isolation and in mature forest at the eastern margin of the Lore Lindu National Park in Central Sulawesi, Indonesia. From April to August 2001 we collected 2322 individuals of fruit-feeding butterflies, belonging to 33 species. Butterfly species richness increased with succession, but was significantly higher in mature forests than in all types of secondary forest. Isolation of the forest fragments did not have a significant effect on butterfly species richness in the range of distances (up to 1700 m) studied. Rather it appeared to affect only a few species. Species richness of endemic species was higher than of non-endemic species. Although endemic species were most diverse in mature forests, many species captured were restricted to secondary forests. Our results show that mature forest is essential for the conservation of nymphalid butterflies and for the endemic species in this area. However, considering the relatively large number of species found in these rather small habitat islands, secondary forest fragments, especially older successional stages, can be taken into account in conservation efforts and thus contribute to the preservation of tropical biodiversity on a landscape scale.  相似文献   

18.

Aim

Comprehensive biodiversity protection necessitates the consideration of multiple indexes of diversity, and how the distribution patterns of priority areas may shift under climate change. Galliformes is a globally endangered avian order vulnerable to climate change that provide an important indicator for wildlife conservation effectiveness. Here, we identified priority areas for conserving Galliformes taxonomic, phylogenetic, and functional diversity in China and their spatial dynamics subject to climate change, and examined how well existing protected areas align with current and future priority areas.

Location

China.

Methods

We applied species distribution modelling and Zonation algorithms to identify conservation priority area dynamics for 47 galliform species across three biodiversity indexes subject to three future climate change scenarios to 2050s and 2070s. We overlaid these identified priority areas onto existing national nature reserves and national parks to assess and project their effectiveness.

Results

Current priority areas proved spatially incongruent between indexes, with an optimal area overlap comprising just 10.3% of China's land area, lying largely outside of existing protected areas. Furthermore, over 80% of modelled optimal priority areas currently lacked formal conservation status. Future priority areas will shift substantially under climate change, to an extent dependent on greenhouse gas emission scenarios. Nevertheless, we identified five large regions where optimal Galliformes diversity indexes should remain stable under all scenarios, thus providing potential climatic refugia, if protected from human encroachment.

Main Conclusions

The current deficits we identified for Galliformes protection in China resonate with a broader need for hierarchical conservation strategic planning across regions and ecosystems to ensure long-term biodiversity protection, accommodating for climate change.  相似文献   

19.
Theobroma cacao plantings, when managed under the shade of rainforest trees, provide habitat for many resident and migratory bird species. We compared the bird diversity and community structure in organic cacao farms and nearby forest fragments throughout mainland Bocas del Toro, Panama. We used this dataset to ask the following questions: (1) How do bird communities using cacao habitat compare to communities of nearby forest fragments? (2) To what extent do Northern migratory birds use shaded cacao farms, and do communities of resident birds shift their abundances in cacao farms seasonally? (3) Do small scale changes in shade management of cacao farms affect bird diversity? Using fixed radius point counts and additional observations, we recorded 234 landbird species, with 102 species that were observed in both cacao and forest fragments, 86 species that were only observed in cacao farms, and 46 species that were restricted to forest fragments. Cacao farms were rich in canopy and edge species such as tanagers, flycatchers and migratory warblers, but understory insectivores were nearly absent from cacao farms. We observed 27 migratory species, with 18 species in cacao farms only, two species in forest only, and seven species that occurred in both habitats. In cacao farms, the diversity of birds was significantly greater where there was less intensive management of the canopy shade trees. Shade tree species richness was most important for explaining variance in bird diversity. Our study shows that shaded cacao farms in western Panama provide habitat for a wide variety of resident and migratory bird species. Considering current land use trends in the region, we suggest that action must be taken to prevent conversion away from shaded cacao farms to land uses with lower biodiversity conservation value.  相似文献   

20.
The Rhytidae (Mollusca; Gastropoda; Pulmonata) are a group of large carnivorous land snails distributed in the southern hemisphere, with a particularly rich fauna in New Zealand. The endemic genus Powelliphanta consists of at least 10 species and many more recognised subspecies, most of which are restricted to the western margin of South Island, New Zealand. Powelliphanta taxa tend to have restricted ecological and spatial ranges among the mountains of this region, with some species being limited to lowland forest and others to habitats at or above the treeline. Among recent discoveries is a population of snails occupying habitat on and around a peak called Mt Augustus, which is situated at the edge of a large and economically important coalfield. Since recognition of the potential biological significance of the Mt Augustus snails in 2004, almost all of their habitat has been destroyed by opencast mining revealing a direct conflict between economic and biodiversity prioritisation. Our analysis of mtDNA sequence data indicate Powelliphanta “Augustus” is a distinctive evolutionary lineage, more closely related to a nearby lowland species Powelliphanta lignaria than the spatial and ecological neighbour Powelliphanta patrickensis. Powelliphanta “Augustus” appears to be a specialised local endemic species. Despite a growing international awareness of the importance of biodiversity conservation, the demand for foreign earnings continues to take priority over the protection of our biota.  相似文献   

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