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1.
The Lord Howe Island stick insect (Dryococelus australis) is one of the world’s rarest insects. However, the opportunity to reintroduce the species to Lord Howe Island, and commence the path to recovery, may occur within the next 5 years. Understanding the insect’s host plant and habitat preferences on Lord Howe Island is critical to maximising the likelihood of reintroduction success. However, very little ecological information was documented before the species became extinct on the island in the 1930s. Here we examine the Lord Howe Island stick insect’s preference for potential host plants, a key aspect of habitat suitability. We conducted preference trials using 15 common plant species found on Lord Howe Island. Both nymphs and adults consumed some but not all of these plant species. Nymphs were able to survive on 7 of these 15 plants for the duration of the 26-day trials although failed to survive on some of the plants most preferred by adults. Overall, these data reveal that there are numerous plants on Lord Howe Island that the stick insect can consume, though their suitability varies with different developmental stages of the insect. These data are encouraging for any future reintroduction attempts and would greatly aid the selection and monitoring of release sites.  相似文献   

2.
Summary   Until its rediscovery on Balls Pyramid in February 2001, the Lord Howe Island Phasmid or Stick Insect ( Dryococelus australis ) was thought to be extinct. It disappeared from Lord Howe Island soon after the accidental introduction of the Ship Rat ( Rattus rattus ) in 1918. In this paper, we report on the recovery actions undertaken for this critically endangered species since its rediscovery. Monitoring of the small surviving population on Balls Pyramid has shown it to fluctuate between about 9 and 35 adult individuals. As a safeguard against extinction, two adult pairs were removed from Balls Pyramid in February 2003 to establish captive populations in Melbourne and Sydney. Although all four founders bred readily in captivity, one pair died only a month after capture. The second female would have also died soon after capture had it not been for veterinary intervention using novel untested techniques. The single surviving pair bred successfully but the hatch rate of eggs was poor. For the next generation, both fecundity and hatch rates were low. The lack of knowledge regarding the specific husbandry requirements of this particular species undoubtedly contributed to these problems. Careful management, together with a cautious scientific approach, eventually led to all problems being resolved. Presently, there are more than 700 individuals and 14 000 eggs in captivity. Approximately 80% of incubated eggs are expected to hatch. To establish additional captive colonies, adults and eggs have been sent to other institutions, both within Australia and overseas. Now that the species is reasonably secure in captivity, the opportunity exists to reintroduce this iconic insect back onto Lord Howe Island, but this can occur only after the introduced rodents have been removed. A programme to eradicate both the Ship Rat and the House Mouse ( Mus musculus ) from Lord Howe Island is currently being developed.  相似文献   

3.
Knowledge of the dispersal capacity of species is crucial to assess their extinction risk, and to establish appropriate monitoring and management strategies. The Providence petrel (Pterodroma solandri) presently breeds only at Lord Howe Island (~32,000 breeding pairs) and Phillip Island-7 km south of Norfolk Island (~20 breeding pairs). A much larger colony previously existed on Norfolk Island (~1,000,000 breeding pairs) but was hunted to extinction in the 18th Century. Differences in time of return to nesting sites are presently observed between the two extant colonies. Information on whether the Phillip Island colony is a relict population from Norfolk Island, or a recent colonization from Lord Howe Island, is essential to assess long-term sustainability and conservation significance of this small colony. Here, we sequenced the mitochondrial cytochrome b gene and 14 nuclear introns, in addition to genotyping 10 microsatellite loci, to investigate connectivity of the two extant P. solandri populations. High gene flow between populations and recent colonization of Phillip Island (95 % HPD 56–200 ya) are inferred, which may delay or prevent the genetic differentiation of these insular populations. These results suggest high plasticity in behaviour in this species and imply limited genetic risks surrounding both the sustainability of the small Phillip Island colony, and a proposal for translocation of Lord Howe Island individuals to re-establish a colony on Norfolk Island.  相似文献   

4.
The ‘tree lobsters’ are an enigmatic group of robust, ground-dwelling stick insects (order Phasmatodea) from the subfamily Eurycanthinae, distributed in New Guinea, New Caledonia and associated islands. Its most famous member is the Lord Howe Island stick insect Dryococelus australis (Montrouzier), which was believed to have become extinct but was rediscovered in 2001 and is considered to be one of the rarest insects in the world. To resolve the evolutionary position of Dryococelus, we constructed a phylogeny from approximately 2.4 kb of mitochondrial and nuclear sequence data from representatives of all major phasmatodean lineages. Our data placed Dryococelus and the New Caledonian tree lobsters outside the New Guinean Eurycanthinae as members of an unrelated Australasian stick insect clade, the Lanceocercata. These results suggest a convergent origin of the ‘tree lobster’ body form. Our reanalysis of tree lobster characters provides additional support for our hypothesis of convergent evolution. We conclude that the phenotypic traits leading to the traditional classification are convergent adaptations to ground-living behaviour. Our molecular dating analyses indicate an ancient divergence (more than 22 Myr ago) between Dryococelus and its Australian relatives. Hence, Dryococelus represents a long-standing separate evolutionary lineage within the stick insects and must be regarded as a key taxon to protect with respect to phasmatodean diversity.  相似文献   

5.
Captive‐breeding programs have been widely used in the conservation of imperiled species, but the effects of inbreeding, frequently expressed in traits related to fitness, are nearly unavoidable in small populations with few founders. Following its planned extirpation in the wild, the endangered red wolf (Canis rufus) was preserved in captivity with just 14 founders. In this study, we evaluated the captive red wolf population for relationships between inbreeding and reproductive performance and fitness. Over 30 years of managed breeding, the level of inbreeding in the captive population has increased, and litter size has declined. Inbreeding levels were lower in sire and dam wolves that reproduced than in those that did not reproduce. However, there was no difference in the inbreeding level of actual litters and predicted litters. Litter size was negatively affected by offspring and paternal levels of inbreeding, but the effect of inbreeding on offspring survival was restricted to a positive influence. There was no apparent relationship between inbreeding and method of rearing offspring. The observable effects of inbreeding in the captive red wolf population currently do not appear to be a limiting factor in the conservation of the red wolf population. Additional studies exploring the extent of the effects of inbreeding will be required as inbreeding levels increase in the captive population. Zoo Biol 29:36–49, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

6.
Information on demographic, genetic, and environmental parameters of wild and captive animal populations has proven to be crucial to conservation programs and strategies. Genetic approaches in conservation programs of Brazilian snakes remain scarce despite their importance for critically endangered species, such as Bothrops insularis, the golden lancehead, which is endemic to Ilha da Queimada Grande, coast of São Paulo State, Brazil. This study aims to (a) characterize the genetic diversity of ex situ and in situ populations of B. insularis using heterologous microsatellites; (b) investigate genetic structure among and within these populations; and (c) provide data for the conservation program of the species. Twelve informative microsatellites obtained from three species of the B. neuwiedi group were used to access genetic diversity indexes of ex situ and in situ populations. Low‐to‐medium genetic diversity parameters were found. Both populations showed low—albeit significant—values of system of mating inbreeding coefficient, whereas only the in situ population showed a significant value of pedigree inbreeding coefficient. Significant values of genetic differentiation indexes suggest a small differentiation between the two populations. Discriminant analysis of principal components (DAPC) recovered five clusters. No geographic relationship was found in the island, suggesting the occurrence of gene flow. Also, our data allowed the establishment of six preferential breeding couples, aiming to minimize inbreeding and elucidate uncertain parental relationships in the captive population. In a conservation perspective, continuous monitoring of both populations is demanded: it involves the incorporation of new individuals from the island into the captive population to avoid inbreeding and to achieve the recommended allelic similarity between the two populations. At last, we recommend that the genetic data support researches as a base to maintain a viable and healthy captive population, highly genetically similar to the in situ one, which is crucial for considering a reintroduction process into the island.  相似文献   

7.
Summary   The Lord Howe Island Biodiversity Management Plan targeted significant species for the Lord Howe Island Group and formed the recovery plan for 30 threatened species and one endangered ecological community. The plan addressed threats and management actions relevant to the Lord Howe Island Group's overall biodiversity, with a particular focus on rare and significant species and communities. The Biodiversity Management Plan approach enabled holistic and cost-effective planning for the management of biodiversity on Lord Howe Island. We describe the approach, as applied to Lord Howe Island, including the utilization of expert and community knowledge, species research data and GIS innovations.  相似文献   

8.
Alice Wells 《水生昆虫》2013,35(3):221-230
Hydroptilid species are described from Lord Howe Island for the first time. All four species are in the endemic Australian genus Orphninotrichia, and all are endemic to Lord Howe Island. Modifications exhibited by these new species to the normally conservative Orphninotrichia features are suggestive of sympatric speciation and, for several, of a shift in larval niche.  相似文献   

9.
Priolepis akihitoi is described as new from Australia, New Caledonia and Japan. The species is distinctive in having a transverse papilla pattern, second dorsal rays usually I, 11, predorsal fully scaled and dark bars dorsally on the caudal fin. Priolepis cyanocephala is described as new from eastern Australia and Lord Howe Island. It differs from other species in having a reduced transverse papilla pattern, second dorsal rays I, 10, predorsal largely naked and head with vertical bands, but no bands on the body. Priolepis profunda is redescribed based on material from northwestern Australia and Thailand, and photos of specimens from Indonesia, New Guinea and the Philippines. Priolepis psygmophilia is redescribed based on recently obtained material from the Kermadec Islands and other material from Lord Howe Island, Easter Island and Rapa Island.  相似文献   

10.
The population of flesh-footed shearwaters (Puffinus carneipes) breeding on Lord Howe Island was shown to be declining from the 1970''s to the early 2000''s. This was attributed to destruction of breeding habitat and fisheries mortality in the Australian Eastern Tuna and Billfish Fishery. Recent evidence suggests these impacts have ceased; presumably leading to population recovery. We used Bayesian statistical methods to combine data from the literature with more recent, but incomplete, field data to estimate population parameters and trends. This approach easily accounts for sources of variation and uncertainty while formally incorporating data and variation from different sources into the estimate. There is a 70% probability that the flesh-footed shearwater population on Lord Howe continued to decline during 2003–2009, and a number of possible reasons for this are suggested. During the breeding season, road-based mortality of adults on Lord Howe Island is likely to result in reduced adult survival and there is evidence that breeding success is negatively impacted by marine debris. Interactions with fisheries on flesh-footed shearwater winter grounds should be further investigated.  相似文献   

11.
In this paper, we describe the utility of microsatellite data and genetic pedigree information to guide the genetic management of two long-term conservation programs for endangered populations of salmon: Snake River Sockeye Salmon, Oncorhynchus nerka, and inner Bay of Fundy Atlantic Salmon, Salmo salar. Both programs are captive broodstock (live gene banking) programs for endangered populations of salmon. In order for these programs to be successful for recovery efforts, genetic change, including accumulation of inbreeding, loss of genetic variation, and adaptation to captivity, must be minimized. We provide an overview of each program, describe broodstock selection and pairing for spawning, and discuss how pedigree data are being used to evaluate different management practices. While there are inherent species and programmatic differences, both of these programs use widely accepted genetic conservation strategies (minimize mean kinship, reduce variance in family size, minimize inbreeding in the next generation, maintain large census and effective population size) to potentially mitigate some unintended side-effects associated with the rearing of small populations in captivity. These case studies highlight the benefits and practical limitations of applying these strategies in the genetic management of salmon, and may be used to inform other conservation programs.  相似文献   

12.
Endemic species are assumed to have a high risk of extinction because their restricted geographic range is often associated with low abundance and high ecological specialization. This study examines the abundance of Chaetodon butterflyfishes at Lord Howe Island in the south‐west Pacific, and compares interspecific differences in local abundance to the feeding behavior and geographic range of these species. Contrary to expected correlations between abundance and geographic range, the single most abundant species of butterflyfish was Chaetodon tricinctus, which is endemic to Lord Howe Island and adjacent reefs; densities of C. tricinctus (14.1 ± 2.1 SE fish per 200m2) were >3 times higher than the next most abundant butterflyfish (Chaetodon melannotus), and even more abundant than many other geographically widespread species. Dietary breadth for the five dominant butterflyfishes at Lord Howe Island was weakly and generally negative correlated with abundance. The endemic C. tricinctus was a distinct outlier in this relationship, though our extensive feeding observations suggest some issues with the measurements of dietary breadth for this species. Field observations revealed that all bites taken on benthic substrates by C. tricinctus were from scleractinian corals, but adults rarely, if ever, took bites from the benthos, suggesting that they may be feeding nocturnally and/or using mid‐water prey, such as plankton. Alternatively, the energetic demands of C. tricinctus may be fundamentally different to other coral‐feeding butterflyfishes. Neither dietary specialization nor geographic range accounts for interspecific variation in abundance of coral reef butterflyfishes at Lord Howe Island, while much more work on the foraging behavior and population dynamics of C. tricinctus will be required to understand its’ abundance at this location.  相似文献   

13.
Australia’s species extinction rate is one of the highest in the world. Yet, there is limited evidence regarding people’s recognition of, and preferences and support for, Australian endangered wildlife. This paper presents survey responses from 223 Zoos Victoria visitors (response rate: 39.1 %) and 90 community members (Victoria, Australia). We examined people’s top 10 overall (global) and Australian favourite animals, and conducted an in-depth exploration of recognition of, and preferences and support for, seven Australian endangered species identified as being at risk of extinction within the next decade, including: the leadbeater’s possum (Gymnobelideus leadbeateri), eastern barred bandicoot (Perameles gunnii), helmeted honeyeater (Lichenostomus melanops cassidix), southern corroboree frog (Pseudophryne corroboree), Lord Howe Island (LHI) stick insect (Dryococelus australis), Tasmanian devil (Sarcophilus harrisii), and the orange-bellied parrot (Neophema chrysogaster). Results indicate that the only Australian animals to feature in the overall top 10 favourite list were the kangaroo (ranked 9th for both sample groups) and koala (ranked 6th and 10th for the community and zoo sample, respectively). The Tasmanian devil had the highest rate of recognition (>86 %), in comparison to the remaining six species (1.2–7.3 % across both samples). Endangered species were not prominent in the top favourite Australian species. Australian endangered species’ likeability ratings typically followed the pattern of mammals being most likeable (Tasmanian devil and leadbeater’s possum), followed by birds, frogs, and insects (helmeted honeyeater, southern corroboree frog, and LHI stick insect). Importantly, for most endangered native species featured (4/7 and 6/7; zoo and community, respectively), simply being able to recognise species significantly (p <.05) increased people’s willingness to support their conservation. Findings underscore several powerful opportunities for future conservation programs to contribute to Australian endangered species conservation by striving to increase public familiarity with Australian species most at risk of extinction.  相似文献   

14.
Phylogenetic relationships are inferred from nuclear ribosomal internal transcribed spacer sequences for species belonging to Sophora sect. Edwardsia from South America, New Zealand, Lord Howe Island, Hawai'i, La Réunion, Easter Island, and Raivavae Island (French Polynesia). Results support the monophyly of sect. Edwardsia , but relationships among the species from this section are poorly resolved due to most species having identical sequences. The origin of Sophora sect. Edwardsia is discussed, as competing hypotheses have proposed the group originated in South America from a North American ancestor, or in the north-west Pacific. We suggest sect. Edwardsia may have arisen in the north-west Pacific from a Eurasian ancestor.  © The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 140 , 435–441.  相似文献   

15.
Porina howeanasp. nov.,P. mariaesp. nov. andP. ocellatoidessp. nov. are described from shaded basalt on Lord Howe Island, New South Wales, Australia.  相似文献   

16.
The lesser kudu (Tragelaphus imberbis) has been kept in North American zoological parks since 1930 but has never been a common species in collections. In 1987 this population totaled 28 animals: 15 males and 13 females. A pedigree evaluation in 1987 of the existing population indicated that eight effective founders and one potential founder were represented in the North American herd. Three new potential founders from European captive populations were added to the population in 1987 to increase the number of existing founder lines to 12 animals. As this species is not endangered or threatened in its native habitat, it is not a high priority to qualify for designation as an SSP species. Because of this, the institutions holding lesser kudu in North America decided to join informally and draft a breeding program to better manage this small captive population. This program was designed to minimize inbreeding and equalize genetic representation of founder animals to maximize genetic diversity. It requires a shift in management philosophy to establish stable groups of breeding females at participating institutions while rotating appropriate breeder males through these herds in a controlled manner to ensure minimization of inbreeding and maximization of genetic diversity. It is hoped that this program can serve as a model for the management of other small captive populations of non-SSP species.  相似文献   

17.
The density of recruits of scleractinian corals on settlement plates at Lord Howe Island, a small isolated sub-tropical island 630 km off the Australian coastline, was within the range of values reported for comparable studies on the Great Barrier Reef. However, there was a difference in the relative abundance of taxonomic groups, with recruitment at Lord Howe Island during the summer of 1990/91 dominated by corals from the Family Pocilloporidae, Family Poritidae, and sub-genus Acropora (Isopora) (in order of abundance). By contrast, on the Great Barrier Reef, recruits are generally predominantly species from the Family Acroporidae (other than the Acropora (Isopora) group). Both the recruits and the established coral communities at Lord Howe Island are dominanted by corals which release brooded planulae, as opposed to the pattern of mass-spawning with external fertilisation more typical of Great Barrier Reef corals. I hypothesise that the release of brooded planulae would be advantageous in an isolated reef community because (a) brooded larvae can travel large distances and survive the journey to the isolated reef and/or (b) brooded larvae have a shorter period before they are competent to settle and are therefore more likely to be retained on the parental reef once a population has been established.  相似文献   

18.
The Lord Howe Island Stick-insect (Dryococelus australis) was formerly abundant on Lord Howe Island, Australia, but was extirpated by Black Rats (Rattus rattus) in the 1920s. The species was thought to be extinct, until freshly dead remains were found by climbers on Balls Pyramid during the 1960s. In February 2001, a survey of Balls Pyramid led to the discovery of a small population of D. australis on a precipitous terrace 65 m above sea level. Two adults and one nymph (all females) were located feeding on an endemic tea-tree (Melaleuca howeana). An accumulation of plant debris at the base of the shrub, kept moist by water seepage, provided the insects with damp hollows suitable for use as daytime refugia. All evidence indicated that the species was confined to this single small terrace. A second survey, in March 2002, located a total of 24 D. australis. Twelve individuals were in the same shrub as that occupied the previous year, and 12 were dispersed among five nearby, smaller shrubs. Ten individuals were able to be sexed – eight females and two males. A number of threats to the population of D. australis on Balls Pyramid are identified and several management actions are proposed to ensure the conservation of the species.  相似文献   

19.
For threatened species with small captive populations, it is advisable to incorporate conservation management strategies that minimize inbreeding in an effort to avoid inbreeding depression. Using multilocus microsatellite genotype data, we found a significant negative relationship between genetic relatedness (inbreeding) and reproductive success (fitness) in a captive population of the critically endangered Black Stilt or KakīHimantopus novaezelandiae. In an effort to avoid inbreeding depression in this iconic New Zealand endemic, we recommend re‐pairing closely related captive birds with less related individuals and pairing new captive birds with distantly related individuals.  相似文献   

20.
Fruit bats of the genus Pteropus are important contributors to ecosystem maintenance on islands through their roles as pollinators and seed dispersers. However, island faunas are the most prone to extinction and there is a real need to assess the possible genetic implications of population reductions in terms of extinction risk. An effective method of ameliorating extinction risk in endangered species is the establishment of captive populations ex situ. The effectiveness of captive breeding programmes may be assessed by comparing the genetic variability of captive colonies to that of wild counterparts. Here, we use polymorphic microsatellite loci to assess genetic variability in wild, critically endangered Rodrigues fruit bats (Pteropus rodricensis, Dobson 1878) and we compare this variability to that in a captive colony. We document remarkable conservation of genetic variability in both the wild and captive populations, despite population declines and founder events. Our results demonstrate that the wild population has withstood the negative effects of population reductions and that captive breeding programmes can fulfil the goals of retaining genetic diversity and limiting inbreeding.  相似文献   

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