摘要:

AbstractDistribution patterns among the terrestrial mammal species of Sakhalin and the main islands of Japan are shown to fall into 12 clear groups. The most fundamental distributional break (Blakiston's Line) is that separating Hokkaido and Sakhalin to the north, with their boreal fauna typical of northern Eurasia, from ‘Hondo’ (Honshu, Shikoku, Kyushu) to the south, which demonstrates a high degree of endemism and supports a small number of Indo‐Malayan elements. Distribution patterns may be explained by considering the Quaternary geohistory of the area, particularly the formation of land bridges and the changes in climatic conditions during this period. A dynamic classification based upon origin of the fauna recognizes seven categories, although on evidence currently available the allocation of some species to categories is not yet possible.Hondo underwent two main periods of land bridge connection to the Asiatic mainland. The first, prior to the Pleistocene, allowed immigration of forms which have since developed into distinctive elements of the endemic fauna (‘Old Hondo Endemics’). The second, during the Middle Pleistocene, brought in widespread Palaearctic species as well as components from South‐East Asia (‘Early Colonists’), some of which have since undergone vicariant speciation (‘New Hondo Endemics’); it also allowed several of the Old Hondo Endemics to extend their range to the mainland and Hokkaido (‘Expanding Hondo Endemics’).Sakhalin and Hokkaido have been more intimately connected to the mainland (most recently until less than 10 000 years ago), such that endemism is very restricted. Species groups here are the ‘Late Colonists’, cold‐adapted tundra species which expanded with the glacial advances, but which are now restricted in distribution, and ‘Recent Colonists’, postglacial forest species which recolonized before the severance of land bridges. Moving the other way were ‘Expanding Northern Endemics’, which arose in Hokkaido or Sakhalin during the last glacial and colonized the adjacent mainland before severance of land links. There are, additionally, several possible Expanding Hondo Endemics in Hokkaido, although human intervention in determining their current distributions cannot be ruled out.Bats, to which the sea barriers of the Japanese area are less complete, exhibit somewhat different patterns of distribution, confirming predictions about the role of even narrow marine straits in re

ISSN:0305-1838    

DOI:10.1111/j.1365-2907.1994.tb00137.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

ISSN:0305-1838    

DOI:10.1111/j.1365-2907.1994.tb00138.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractThe origins, early history, captive populations, spread and habitat preferences of Reeves' Muntjac in Britain are reviewed. It is suggested that much of the published information on the history of Muntjac in Britain is based on misconceptions, and that each subsequent report has continued to promulgate a false impression on the origins, time‐scale and pattern of spread of the species in Britain. Indian and Reeves' Muntjac were introduced to Woburn Park in Bedfordshire within a year of each other, and it appears that the Indian Muntjac did not thrive, at least in the decade following their introduction. How long they survived as a free‐living species in Britain is unclear, but it was probably only a few years. However, there is some evidence to suggest that they might have persisted within the Park at Woburn until 1930.Following the first releases from Woburn in 1901, the numbers of free‐living Reeves' Muntjac in Britain remained low until the 1920s, when populations were largely confined to the woods around Woburn, and possibly also around Tring in Hertfordshire. However, in the 1930s and 1940s there were further deliberate introductions in selected areas some distance from Woburn. As a consequence, the subsequent spread of Reeves' Muntjac was from several main foci, i.e. from the vicinity of Woburn, the Norfolk/Suffolk border, three sites in Northamptonshire, two sites in Oxfordshire and two in Warwickshire. The spread in the second half of this century has been aided by further deliberate and accidental releases, and by these means new populations continue to be established outside the main range. Thus the natural spread has been much less impressive than previously assumed; even in areas with established populations it takes a long time for Muntjac to colonize all the available habitat. Data from a number of areas in Britain suggest that the natural rate of spread is about 1 km a year, which is comparable to other species of deer in Britain.The many introductions have complicated an analysis of the habitat preferences of Reeves' Muntjac, and no clear trends could be found. It would appear that Reeves' Muntjac are less dependent on specific types of habitat than previously believed. Examination of the land‐class preferences using resource selection indices showed that arable land classes were predominantly selected for, and that marginal upland land classes tended to be avoided. Subsequent logistic regression models based on the land classes selected (and to a lesser extent avoided) by Muntjac were able to predict accurately the current distribution of Reeves' Muntjac in Britain, and one of these, together with our knowledge of their history and spread, was used to infer those areas most likely to be colonized by Muntjac in the near future. The greatest potential for range expansion is in Kent and Sussex, and to a lesser extent north into Lincolnshire, Nottinghamshire and south Yorkshire, and west into Cheshire and north Shropshire. However, long‐established populations in areas such as Betws‐y‐Coed in Wales show that Muntjac may persist in low numbers in atypical habitats. Future habitat changes, such as the planting of new woodlands, and continued deliberate and accidental releases, are likely to lead to population changes in addition to those predicted by the logistic reg

ISSN:0305-1838    

DOI:10.1111/j.1365-2907.1994.tb00139.x

出版商:Blackwell Publishing Ltd    

年代:1994

数据来源: WILEY