摘要:

AbstractThe ecology of the free‐ranging Exmoor ponies has not previously been studied. In this investigation, the locations of the few pure‐bred herds are given, together with information on their populations, and the reasons for selecting the Withypool Common herds are outlined. The features of this main study area, the types of ponies and their special groupings are described in some detail. The home ranges of the Exmoor herds are examined on an annual and monthly basis, and their relationships to each other and to that of the mongrel herd are studied. This is followed by information on the changing patterns of the two Exmoor pony ranges and a discussion of the significance of inter‐stallion relationships. Finally, the home range systems are assessed for features of territori

ISSN:0305-1838    

DOI:10.1111/j.1365-2907.1979.tb00228.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

AbstractHabitat preferences of fifteen species of ungulate were studied between July and September 1975 in dry savanna woodland of Mwabvi Game Reserve, Southern Malawi, Central Africa.Thirteen vegetation types were recognized using vegetation transects and plotless sampling techniques (but three of these are omitted from further analysis here either because of the difficulty of sampling in a representative manner or because of their infrequency). A combination of six methods was used to study habitat preferences since each had particular advantages or disadvantages, although quadrat sampling of fresh pellets/spoor counts was the most satisfactory and so used predominantly.The most common and widely distributed species was the Greater kudu, although abundance estimates in different habitats varied according to the method used. Pellet/spoor counts showed heavy use of open grassland by kudu which was not detected by daytime drives. Temporal patterns of activity indicated that the species was moving into more closed woodland during the day and only coming out into open grassland at night. Relative abundance estimates of a species may also be affected by changing group size. The mean group size of kudu increased in more open vegetation, although group size in warthog did not show this relationship. Some species, e.g. impala, reedbuck, and klipspringer showed narrow habitat preferences, occurring in only one or a few vegetation types, whilst others, e.g. kudu, sable, duiker, suni, and grysbok showed much broader preferences.MixedColophospermum mopane /Acaciawoodland had the highest species diversity but rather low abundance. Open grassland andAcacia/Albiziawoodland had high species diversity together with the greatest abundance of ungulates. OpenJulbernardia/Diplorynchus, Brachystegia/Julber‐nardiawoodland, and particularlyPterocarpus/Diplorynchus/Combretumhill woodland had the lowest species diversity and abundance of ungulates. Ready access to cover and availability of suitable food plants probably account for the preferences of certain vegetation types over others, whilst the different behavioural ecology and food preferences of each species account for individual species differences. Access to water probably also determines habitat preferences in particular species, and studies during the wet season may show different distribution

ISSN:0305-1838    

DOI:10.1111/j.1365-2907.1979.tb00229.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

AbstractIn Ndumu Game Reserve, South Africa, it was found that nyala males exhibited no seasonal sexual cycle. Although conceptions occurred throughout the year, there was a bimodal pattern of conceptions with the peaks in autumn and spring.After referring to other African bovids which also have bimodal patterns of reproductive activity, it was concluded that the cues for the two peaks are as yet unknown but must be provided by light or photoperiod. The factors which ultimately decide the amplitude of the peaks are vegetation phenology and feeding style of the animal. In nyala, peaks are masked by the occurrence of post‐partum oestrous cycles and a gestation period of approximately 7 month

ISSN:0305-1838    

DOI:10.1111/j.1365-2907.1979.tb00230.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY

摘要:

AbstractYankari Game Reserve in northeastern Nigeria consists largely of savanna woodland with trees on the better soils growing to 15 m and with spreading crowns. On shallow and stony soils the tree height is generally less and the canopy is discontinuous. The Gaji River riparian zone supports a wide variety of vegetation types ranging from evergreen, closed canopy forest to sedge meadows and patches of open grassland.Elephant (Loxodonta africana) range backwards and forwards along the riparian strip, feeding on perennial grasses and a variety of browse material and utilizing closed canopy forest patches for shade cover. The major movement patterns of other important herbivore species are perpendicular to the riparian strip. Areas used intensively are: waterbuck (Kobus defassa)–open savanna woodland immediately behind the riparian strip: Western hartebeest (Alcelaphus buselaphus major)– open grassy habitat in relatively poor woodland at middle distances from the river; Roan antelope (Hippotragus equinus)–patches of well‐developed and infrequently burned woodland, often at major distances from the river. Buffalo (Syncerus caffer brachyceros) during the dry season ranged between the riparian grassland areas and the more open sections of nearby savanna woodland, but travelled out to distant sections of the reserve after rainwater pools had formed.A major problem in management was the development of a burning policy that would maintain an appropriate balance between perennial and annual grasses and the shade providin

ISSN:0305-1838    

DOI:10.1111/j.1365-2907.1979.tb00231.x

出版商:Blackwell Publishing Ltd    

年代:1979

数据来源: WILEY