Pentalagus Research Articles

A case study of feral cat predation on a weaning juvenile of the Amami rabbit as revealed by a camera trap survey in Amami-Oshima Island in Japan

A case study of feral cat predation on a weaning juvenile of the Amami rabbit as revealed by a camera trap survey in Amami-Oshima Island in Japan

P4011 Analysis of Cytochrome b gene variations shows that Amami rabbit (pentalagus furnessi) and European rabbit (oryctolagus cuniculus) have close genetic structure

P4011 Analysis of Cytochrome b gene variations shows that Amami rabbit (pentalagus furnessi) and European rabbit (oryctolagus cuniculus) have close genetic structure

Endemic Amami Jay, invasive Small Indian Mongoose, and other alien organisms: a new century investigation of island aliens towards improved ecosystem management

The Amami Islands in southern Japan host many endemic species, including Amami Jay (Garrulus lidthi). Following the introduction of Small Indian Mongoose (Herpestes auropunctatus) in 1979, populations of Amami Rabbit (Pentalagus furnessi), Amami Woodcock (Scolopax mira), Amami Ishikawa’s Frog (Odorrana splendida), and other endemic species declined in the 1990s, as the mongoose expanded its population. A mongoose control project since 2000 successfully reduced the mongoose population to a very low density by 2014, resulting in the initial recovery of severely affected animal populations. Amami Jay was removed from Japan’s endangered species list in 2008. However the population and range of Amami Jay are still small (ca. 700 pairs, sometimes with other family member(s), in 700 km2), and other invasive species, such as cats and black rats, continue to damage the native ecosystem. Additionally there is a constant threat of new invasions to the Amami Islands. Our research shows that Amami Jay breeding success depends on the dominant oak (Castanopsis sieboldii) acorn production as much as predation. Therefore conservation plans should consider both short- and long-term effects and potential interaction by both invasive species and other natural factors. Understanding the Amami Jay population dynamics and sustainability from the multiple view points of, such as, population ecology, disease ecology, genetics, and also with ex situ conservation efforts as they relate to invasive species demands, will sophisticate our ecosystem research and management. We discuss how this endeavor of ours might develop as a model activity for maintaining biodiversity under threat from multiple invasive species.

Conservation and management of terrestrial mammals in Japan: its system and practices

Discussion and Conclusions: The proportion of natural forests was reduced to about 40 % of the total area of forests by 2013. The most influential laws for wildlife conservation and management in Japan are the “Act on the Conservation of Endangered Species of Wild Fauna and Flora” and “Wildlife Protection and Proper Hunting Act”. The Amami rabbit (Pentalagus furnessi), the Bonin flying fox ( Pteropus pselaphon), a subspecies of Ryukyu flying fox ( Pteropus dasymallus daitoensis), and two subspecies of the leopard cat (Prionailurus bengalensis iriomotensis and P. b. euptilurus) are conserved under the “Act on Conservation of Endangered Species of Wild Fauna and Flora”, whereas the conservation of many endemic terrestrial species that are ranked high in conservation status are not implemented in Japanese laws. Recently many management practices have been developed for overabundant populations of the sika deer (Cervus nippon) and the wild boar (Sus scrofa) under “Wildlife Protection and Proper Hunting Act”.

Feral cat diet and predation on endangered endemic mammals on a biodiversity hot spot (Amami–Ohshima Island, Japan)

Context There has been concern that feral cats have negative impacts on the endangered endemic mammals of Amami-Ohshima Island, Japan, including the Amami rabbit, Pentalagus furnessi, Ryukyu long-tailed giant rat, Diplothrix legata, and Amami spiny rat, Tokudaia osimensis. However, no diet study of feral cat has been conducted to support the necessity of an urgent feasible feral-cat management for the island. Aims The aims of the present study were to analyse feral-cat diet on Amami-Ohshima Island by using scat analysis and estimate the potential predation impact of feral cats on endangered mammals on the island. Methods The diet of feral cats was studied using scat analysis. We estimated the number of prey, percentage of prey, frequency of occurrence (the percentage of scats in a sample containing a particular prey item), percentage of biomass (biomass of the same prey item divided by the total consumed biomass ×100) and daily consumed biomass (DCB). Key results Three endangered endemic mammals were the main prey species of the feral cat diet (65% of total DCB). The percentage contributions of these species on DCB were long-tailed giant rat (34.7%), Amami spiny rat (21.9%) and Amami rabbit (12%). Conclusions Mammals, especially endangered endemic mammals, were main prey species of feral cat on Amami Island. In Amami Island, where native and invasive rodents coexisted, feral cats consumed more native (56.6%) than invasive (22.2% for Rattus rattus) species. Implications Feral cats are likely to be having a significant impact on endangered endemic mammals on the island. To ensure the long-term survival of these endemic species, active management of the feral-cat population should be considered.

Hypolagus balearicusQuintana, Bover, Alcover, Agustí & Bailon, 2010 (Mammalia: Leporidae): new data from the Neogene of Eivissa (Balearic Islands, Western Mediterranean)

ABSTRACT New remains of Hypolagus balearicus Quintana, Bover, Alcover, Agusti & Bailon, 2010 from Ses Fontanelles (Eivissa) gives new information concerning this Early Pliocene endemic leporid from Eivissa and Mallorca (Balearic Islands, Western Mediterranean sea). The body mass estimated for H. balearicus ranges from 1.3 to 2.7 kg, which is small in comparison to other species of the same genus. The cranium of H. balearicus is proportionally short and has relatively smaller orbits than Oryctolagus cuniculus (Linnaeus, 1758). Remarkable in the usually conservative (in leporids) postcranial skeleton is the particular morphology of the elbow (with crests and pits with a soft outline) and its length in relation to the length and the transversal diameter of the humerus, which yields similar proportions to those of the Amami rabbit Pentalagus furnessi (Stone, 1900) from Amami-Ohshima Island and Tokuno-Shima Island (Japan). In contrast, the diaphysis of the ulna shows a robustness comparable to that observed in...

Dermatitis Associated with Infestation of a Trombiculid Mite, Leptotrombidium miyajimai, in an Amami Rabbit (Pentalagus furnessi)

Severe dermatitis caused by trombiculid mite infestation was observed in an Amami rabbit (Pentalagus furnessi). The mite was identified as Leptotrombidium miyajimai. This is the first report of trombiculid mite-associated cutaneous lesions in Amami rabbits and also the first direct evidence of L. miyajimai parasitism of this host species.

Evaluating the “recovery level” of endangered species without prior information before alien invasion

For maintaining social and financial support for eradication programs of invasive species, quantitative assessment of recovery of native species or ecosystems is important because it provides a measurable parameter of success. However, setting a concrete goal for recovery is often difficult owing to lack of information prior to the introduction of invaders. Here, we present a novel approach to evaluate the achievement level of invasive predator management based on the carrying capacity of endangered species estimated using long-term monitoring data. In Amami-Oshima Island, Japan, where the eradication project of introduced small Indian mongoose is ongoing since 2000, we surveyed the population densities of four endangered species threatened by the mongoose (Amami rabbit, the Otton frog, Amami tip-nosed frog, and Amami Ishikawa's frog) at four time points ranging from 2003 to 2011. We estimated the carrying capacities of these species using the logistic growth model combined with the effects of mongoose predation and environmental heterogeneity. All species showed clear tendencies toward increasing their density in line with decreased mongoose density, and they exhibited density-dependent population growth. The estimated carrying capacities of three endangered species had small confidence intervals enough to measure recovery levels by the mongoose management. The population density of each endangered species has recovered to the level of the carrying capacity at about 20–40% of all sites, whereas no individuals were observed at more than 25% of all sites. We propose that the present approach involving appropriate monitoring data of native organism populations will be widely applicable to various eradication projects and provide unambiguous goals for management of invasive species.

アマミノクロウサギ（<I>Pentalagus furnessi</I>）における慢性化膿性中耳炎・内耳炎による前庭障害の一例

2010年3月に前庭障害を呈したアマミノクロウサギ（Pentalagus furnessi）の雌成獣が保護され，保護されてから6日後に死亡した。病理検査の結果，右耳において慢性化膿性中耳炎・内耳炎が認められ，これによって前庭障害が生じたものと考えられた。

Induced Estrus in Female Small Asian Mongooses (Herpestes javanicus) for the Purpose of Controlling Invasive Alien Species in Okinawa Island

The small Asian mongoose (Herpestes javanicus) belongs to the family Herpestidae, order Carnivora, and originally inhabited Iraq through northern India to extreme southern China and Indonesia, the Malay Peninsula, Hainan, Java (Nowak 2005). Mongooses, including small Asian mongooses, have been widely introduced by people to exterminate rats for pest control (Yamada and Sugimura 2004). In Japan, small Asian mongooses were introduced to eliminate yellow-spotted pit vipers (Habu snakes; Protobothrops flavoviridis) and sugarcane rats on Okinawa Island in 1910 and Amami-Oshima Island, Kagoshima Prefecture in 1979 (Yamada 2002). Naturalized and overbred mongooses, which prey on insects, reptiles, small mammals, wild birds and domestic fowl, have impacted the poultry industry, and threaten the survival of rare endemic species, such as the Amami rabbit (Pentalagus furnessi), Okinawa rail (Galirallus okinawae) and so on (Yamada 2002). A mongoose eradication project led by the Ministry of the Environment, Government of Japan, has been conducted on Amami-Oshima Island since 1996 and northern Okinawa Island since 2000. Moreover, mongooses were designated as invasive alien species by the Invasive Alien Species Act in Japan (Ministry of the Environment, 2004); however, the eradication project has not yet succeeded. The distribution of mongooses has expanded on Okinawa and Amami-Oshima Islands and, in addition, mongooses were found in Kagoshima city (Kyusyu Island) in 2007. Currently, cage-type traps and cylindrical trapping with bait, chicken meat, have been mainly used for capturing mongooses on Okinawa and Amami-Oshima Islands. Mongoose-drawing techniques require a more effective for increase of the capture number. For effective capture, studies searching for and identifying attractant substances for species-specific capture have been performed in small Asian mongooses, and the previous study attempted to identify volatile fatty acids from anal sac secretions in this species (Ogura et al. 2000b). In the present study, to establish a trapping method with an estrous female or its excreta, we tried to create a protocol to artificially induce estrus in female small Asian mongooses using exogenous hormonal treatment. Estrus was determined based on the profile of urinary estrogen concentrations.

A shared unusual genetic change at the chemokine receptor type 5 between Oryctolagus, Bunolagus and Pentalagus

Whereas in most leporid species studied the effects of exposure to Myxoma virus (MV) are benign, in the European rabbit (Oryctolagus cuniculus) it causes an epizootic disease with particularly high mortality rates, known as myxomatosis. Chemokine receptors are known to play an important role in infection by large DNA viruses such as MV, by acting as portals for viral entry into the host cell. As with the human immunodeficiency virus, CCR5 is among the major candidates to affect resistance to myxomatosis. Previous sequence comparisons of the CCR5 gene among Leporid species revealed that a drastic change occurred at the second extracellular loop which was unique to the European rabbit species. Here we report that European rabbit shares this particular alteration with two of its closest relatives: the South African Riverine rabbit (Bunolagus monticularis) and the Japanese Amami rabbit (Pentalagus furnessi). Both species represent monotypic genera and are included in the IUCN Red List as Endangered. It would then be urgent to study the susceptibility of these species to myxomatosis. Despite the lack of direct evidence that the altered CCR5 can affect the outcome of exposure to MV, the reported findings justify preventive measures to be considered.

Isolation and characterization of microsatellite loci in the Amami rabbit (Pentalagus furnessi)

We report on the isolation and characterization of eight polymorphic and five monomorphic microsatellites in the Amami rabbit (Pentalagus furnessi). Microsatellite polymorphism was determined using 25 individuals. There were 2–11 alleles for each polymorphic locus with heterozygosity ranging between 0.08 and 0.76. Linkage disequilibrium was not suggested between any pairs among the eight polymorphic loci. We suggest that these primers be used in future studies to monitor population size, determine dispersal patterns, and genetic diversity within and between populations of this and related species.

Lagomorph biology: evolution, ecology, and conservation

Palaeontology and Evolution.- to the Lagomorpha.- Prehistoric and Historic Artificial Dispersal of Lagomorphs on the Mediterranean Islands.- The Lagomorph Fossil Record and the Origin of the European Rabbit.- Inferring the Evolutionary History of the European Rabbit (Oryctolagus cuniculus) from Molecular Markers.- Phylogenetic Aspects of Nuclear and Mitochondrial Gene-Pool Characteristics of South and North African Cape Hares (Lepus capensis) and European Hares (Lepus europaeus).- Population Ecology and Dynamics.- The World of Pikas.- When? Where? and for How Long? Census Design Considerations for an Alpine Lagomorph, the Collared Pika (Ochotona collaris).- Weather Effects on Reproduction, Survival, and Body Mass of European Rabbits in a Temperate Zone Habitat.- Ecosystem Engineering Effects of European Rabbits in a Mediterranean Habitat.- Forest-Fire Regime: The Missing Link to Understand Snowshoe Hare Population Fluctuations?.- Introduced Lagomorphs as a Threat to Native Lagomorphs: The Case of the Eastern Cottontail (Sylvilagus floridanus) in Northern Italy.- Testing Multiple Hypotheses to Identify Causes of the Decline of a Lagomorph Species: The New England Cottontail as a Case Study.- Physiology and Behaviour.- Many Common Odour Cues and (at Least) One Pheromone Shaping the Behaviour of Young Rabbits.- Mother-Young and Within-Litter Relations in the European Rabbit Oryctolagus cuniculus.- Fertility and Infertility in the European Hare Lepus europaeus in Australia.- A Review of Competition between Rabbits (Oryctolagus cuniculus) and Hares (Lepus europaeus).- Diseases.- European Brown Hare Syndrome.- How Many Caliciviruses are there in Rabbits? A Review on RHDV and Correlated Viruses.- Geographic and Seasonal Variation in the Impact of Rabbit Haemorrhagic Disease on European Rabbits, Oryctolagus cuniculus, and Rabbit Damage in Australia.- Conservation and Management.- Conservation of Endangered Lagomorphs.- Managing the European Rabbit: Converging Interests Between Australian Research for Rabbit Control and European Research for their Conservation.- Improving Rabbit Restocking Success: A Review of Field Experiments in France.- Recovering the Endangered Riparian Brush rabbit (Sylvilagus bachmani riparius): Reproduction and Growth in Confinement and Survival after Translocation.- Conservation of Critically Endangered Lagomorphs: The Tehuantepec Jackrabbit (Lepus flavigularis) as an Example.- A Review of the Biology and Conservation of the Amami Rabbit (Pentalagus furnessi).- Concluding Remarks.- Overview of Lagomorph Research: What we have learned and what we still need to do.

Accumulation of Hg and other heavy metals in the Javan mongoose ( Herpestes javanicus) captured on Amamioshima Island, Japan

Concentrations of 22 elements (Mg, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, Tl, total Hg (T-Hg), Pb) and organic Hg (O-Hg) were examined in the liver, kidney and brain of the Javan mongoose ( Herpestes javanicus) and in liver of the Amami rabbit ( Pentalagus furnessi) from Amamioshima Island in Japan. Relatively high levels of T-Hg levels (from 1.75 to 55.5 μg g −1 wet wt.) were found in the Javan mongoose. As for a comparison of hepatic T-Hg concentrations between the two areas, there was no significant difference between the Javan mongoose in Amamioshima and those in the Okinawa islands. In addition, T-Hg levels in the livers of the Amami rabbit were the same as in the livers of other herbivorous mammals. Taken together, it suggested that T-Hg accumulation in the livers of the Javan mongoose was not affected by the environment but by a specific physiological mechanism. The comparison of Hg and other heavy metal accumulations between terrestrial mammals (13 species, 61 individuals) including the Javan mongoose and marine mammals (18 species, 508 individuals) were also discussed.

Distribution and abundance of the Amami rabbit Pentalagus furnessi in the Amami and Tokuno Islands, Japan

AbstractThe Amami rabbit Pentalagus furnessi is a rare forest-dwelling form endemic to the Amami and Tokuno Islands in Japan. In order to estimate the distribution and abundance of the Amami rabbit we counted their faecal pellets along forest roads and streams as well as within the forests on Amami and Tokuno Islands during January 1993–March 1995. The number of pellets/ km along a stream gave a practical index for measuring relative abundance. The rabbit was estimated to be distributed over about 370 sq km on Amami Island and 33 sq km on Tokuno Island. There was a large variance in faecal abundance among the survey routes. Some populations were completely isolated and thought to be very small. The size of a local population was positively correlated with those of neighbouring populations and the amount of mature forest relative to other serai stages. We compared the results of this survey with those of previous surveys to find that the total population of this species appears to be declining. Some conservation measures are proposed for forest habitat management, designed to avert the decline of the Amami rabbit and to ensure its preservation.

Distribution and abundance of the Amami rabbit Pentalagus furnessi in the Amami and Tokuno Islands, Japan

The Amami rabbit Pentalagus furnessi is a rare forest-dwelling form endemic to the Amami and Tokuno Islands in Japan. In order to estimate the distribution and abundance of the Amami rabbit we counted their faecal pellets along forest roads and streams as well as within the forests on Amami and Tokuno Islands during January 1993–March 1995. The number of pellets/ km along a stream gave a practical index for measuring relative abundance. The rabbit was estimated to be distributed over about 370 sq km on Amami Island and 33 sq km on Tokuno Island. There was a large variance in faecal abundance among the survey routes. Some populations were completely isolated and thought to be very small. The size of a local population was positively correlated with those of neighbouring populations and the amount of mature forest relative to other serai stages. We compared the results of this survey with those of previous surveys to find that the total population of this species appears to be declining. Some conservation measures are proposed for forest habitat management, designed to avert the decline of the Amami rabbit and to ensure its preservation.

Present Status and Conservation of the Endangered Amami Rabbit Pentalagus furnessi.

The Amami rabbit Pentalagus [urnessi is an endemic species of the central Ryukyus, Japan, and occurs only on two islands, Amami Oshima I. and Tokunoshima I. For the conservation of this species, some research programs to reveal the population size, spatial and temporal patterns of activity, and impacts of introduced predators were carried out. The habitat available to the rabbit has obviously been reducing with considerable fragmentation on each island, and size of each population also seems to have been decreasing as well (2700-6500 in total of the two islands in 1995). The estimated home range size was relatively small (1.3 ha for males and 1.2 ha for females), and the rabbits moved 100-200 m from their burrows mainly during the night. The negative impact of the introduced mongoose on the rabbit was quite serious on Amami Oshima I., and effective control of this exotic predator is an urgent necessity for the conservation of the rabbit, as well as the whole ecosystem, of this island.

A survey of fungi which kill microscopic animals in the dung of the Amami rabbit

Dung of the early-evolved Amami rabbit of Japan was surveyed for the presence of fungi which attack microscopic organisms. Several species of predacious nematophagous fungi and species endoparasitic in nematodes and rotifers were found. In addition, zygomycetous species attacking amoebae and tardigrades, and one flagellate zoosporic species holocarpic in various host organisms, were found.

The Role of Government Subsidies in the Population Decline of Some Unique Wildlife Species on Amami Oshima, Japan

Amami Oshima (Island of Amami) in Japan has five species and two supspecies of animal wildlife that are designated as natural monuments by the national government. However, government subsidy has indirectly induced population decline of some of them through habitat destruction. Self-supporting industries make up only a small portion of the whole economy of Amami Oshima, so that financial support from the national and prefectural governments has been necessary to create a large number of jobs for local people.Forestry has been subsidized by the central governments to a large degree. As a result of cost-reduction in logging through the subsidy which has been devoted mostly to construction of logging roads, most original forests have been replaced by young secondary forests and logged areas in the central part of Amami Oshima, where all the wildlife taxa under consideration are to be observed at present. The governments have planned to manage these young forests with a 35–40 years' rotation-cycle for pulpwood, of which the commercial value is relatively low.Of the involved seven species and subspecies, the Great White's Thrush (Turdus dauma amami), Owston White-backed Woodpecker (Drendrocopos leucotos owstoni), and the Long-haired Rat (Rattus legata), appeared to be so dependent on mature forest (uncut for at least 40 years after selective felling) that they will probably not be able to maintain their populations if all the old forests are cut down. Small populations of the Ryukyu Robin (Erithacus komadori) may be able to survive in young secondary forests, but population decline will be substantial through the decrease in the area of mature forest. On the other three species—the Amami Rabbit (Pentalagus furnessi), Purple Jay (Garrulus lidthi), and Spinous Rat (Tokudaia osimensis)—the effects of clear-cutting of the mature forests are less obvious. Further decreases in the area of mature forests will probably cause a significant reduction in the present population-level of the Amami Rabbit, but negative effects of logging on the other two species should not be very serious. An increase in the length of rotation-cycles, and changes in the use of the subsidy, are proposed for improving the wildlife habitat and the economic efficiency of local forestry.

A new stomach worm, Obeliscoides pentalagi n. sp. (Nematoda; Trichostrongyloidea) of Ryukyu rabbits, Pentalagus furnessi (Stone, 1900)

A new trichostrongylid nematode, Obeliscoides pentalagi n. sp., from the stomach of the Ryukyu Rabbit, Pentalagus furnessi, collected on Amami-ohshima Island, south Japan is described. O. pentalagi n. sp. resembles O. leporis Schulz, 1931 and O. travassosi Liu & Wu, 1941, but differs in the relative size and morphology of the dorsal ray and genital cone of the males. The number and distribution of longitudinal cuticular ridges of O. pentalagi n. sp. is similar to those of O. cuniculi multistriatus Measures & Anderson, 1983, but it differs in the morphology of the spicules, dorsal ray and genital cone in males, and in the morphology of the prevulval lobe of the females. The discovery of O. pentalagi further supports the hypothesis of a Eurasian origin of the genus Obeliscoides (Graybill, 1923) Graybill, 1924 (Durette-Desset, 1983; Durette-Desset & Chabaud, 1977; Measures & Anderson, 1983a, b, c, 1984). The number and distribution of longitudinal cuticular ridges and variation of the prevulval lobe in females of O. leporis Schulz, 1931 are also examined and compared with those of other species.