摘要:

ABSTRACTBetween March and December 1990, a survey of PineMarten Martes martesL. on the Balearic Islands of Minorca and Majorca was carried out. Pine Marten were found distributed over 55% of Minorca and occupied Aleppo Pine and Holm Oak forests, mediterranean shrublands and riparian/ cliff habitats. In Majorca, Pine Marten were found on 48% of the island and three broad physiographic areas, the Sierra de Tramuntana, Sierra de Levant and the Massif de Randa. Droppings were collected along four designated routes during five bimonthly intervals in Minorca to describe the Pine Marten's differential use of habitat types. The upland/open pine forest had the highest use index while the Holm Oak forest had the lowest. The number of Pine Marten faeces collected was greatest during the months of July‐August. The Balearic Island Pine Marten populations were once on the verge of extinction; however, protection during the last 20 years has enabled the species to recover throughout most of the forested habitats on both islands. Resource managers must carefully monitor the Pine Marten populations to provide the species and its habitat with adequate protection and management in the futur

ISSN:0305-1838    

DOI:10.1111/j.1365-2907.1993.tb00417.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

ABSTRACTWatts 1969 described the population cycle of the Wood Mouse Apodemus sylvaticus as a decline in numbers in spring, a stable period in summer and an increase phase in autumn. Aggression by adult males was considered an important aspect of population regulation limiting male survival in spring and juvenile recruitment in summer. However, recent studies of range behaviour and experimental investigations suggest that maleA. sylvaticusare not relevant in population regulation and that the principal regulating factors act on female reproductive success. Female reproductive activity is determined by spatial interactions which, in turn, are determined primarily by the density of females and the proportion of female immigrants in the population. The only impact adult males may have on population size is through infanticide and competition with the females for food.

ISSN:0305-1838    

DOI:10.1111/j.1365-2907.1993.tb00418.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

ABSTRACTMembers of the genusSciurusstore seed when plentiful by scatterhoarding. Such caches are impossible to defend and vulnerable to both interspecific and intraspecific competitors. In view of the delicate position held by Red SquirrelsSciurus vulgarisL. in Britain it is of value to extend to this species studies of the methods whereby such competition is reduced. Caching behaviour in a population of Red Squirrels living in a protected reserve and receiving supplementary food was studied for 18 months. Two main aspects were investigated; their ability to find caches they had not made, and their efforts to reduce competition for caches they did make. Stapanian&Smith (1978) predicted that caches are made at an optimal density and that the entire 360d̀ arc around a resource is used. This study upheld this second prediction but not the first for the population of Red Squirrels in question. In addition, it is suggested that caching cannot be considered to be permanent under conditions of surplus food

ISSN:0305-1838    

DOI:10.1111/j.1365-2907.1993.tb00419.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY