The British pine marten Martes martes population was heavily persecuted in the nineteenth century, particularly in England and Wales. By 1914 it was reduced to inhabiting a small area of northern Scotland, with a smaller population said to occur in Wales and several small fragments in northern England. A survey based on scat searches on 700 m transects, carried out at a density of one per 10 km x 10 km square over 1980-82, showed that the Scottish population had increased its range in recent years. This was considered to be due to both reforestation and the reduction in persecution following the 1914-1918.war. However, no scats could be found in the 36 survey sites in England and Wales. Hence the present survey concentrating on these countries was carried out over 1987-88, in order to provide a baseline for further work and to ascertain whether these populations still existed at that date. This survey first built a database of records of sightings and bodies over the last 190 years (augmented by recent interviews), and mapped these to circumscribe the most likely areas of present occupation. These areas were subsequently to be surveyed intensively for signs of marten.

 

A total of 861 records of sightings and bodies were divided into 8 periods for mapping. They showed that the English population was divided into four main fragments or sub populations: a) Northumberland Eastern Cumbria/Durham: b) North Yorkshire c) Cumbria/Lancashire: d) West and South Yorkshire. The main Welsh population (E) occurred in northern Wales (Gwynedd) with a much small separate fragment in south-central Wales. There were sightings in all six of these fragments in the last period (1983-1988) before the survey date. However, the dates for the most recent confirmed bodies from the populations a to e were 1986, 1983, 1981, 1971 and 1987, and their last confirmed breeding records were in 1987, 1981, 1960s, 1970 and 1988. Populations a, b and e showed an increasing progression in the numbers of all records from 1960 to 1988, but populations c and d showed a decline in records over the same period.

 

A total of 896 field survey transects 2 km in length were selected in the areas containing the sighting records (ie they were not random) and these were examined for signs of martens between June 1987 and July 1988. The transects were sited in 144 10 km x 10 km squares at a mean density of 6.22 transects per square. 212 of these transects were then resurveyed between August and December 1988. A total of 78 (8.7%) sites in 35 squares were found to be 'positive' at first survey. This was increased to 100 (11.2%) in 39 squares after resurvey. The percentage of sites occupied in populations a to e was 14.3, 13.2, 13.9, 0 and 9.7% respectively after resurvey.

 

The method used for the field survey was tested in areas known to be inhabited by martens in Scotland and was 91.7% successful. Further validation was obtained by comparing the results of the two separate record and field surveys. Although the data were independently collected they showed correlations on three major points.

 

Signs of martens were sparse in England and Wales (mean: 0.54 per 500 m) compared to Scotland (mean: 2.64 per 500 m). This suggested that the reason for the lack of positive survey sites in 1980-82 may have been that the transects were too short and at too low a density, rather than absence of martens.

 

It was concluded overall that though all five of the main populations south of Scotland were still extant in 1988, they existed at very low densities and only one of them (a) may have been spreading, whilst three (b, c and d) may have been contracting their ranges. Populations c and d may have been declining in numbers since 1960-76, and this had proceeded to the point where there may have been very few pine martens left in population d in 1988.

 

It was considered that there has been a continuous inhabitation of parts of southern England by pine martens this century. Those found along the English-Welsh border and those on the east coast originated almost certainly by movement from populations e and b, respectively. Those of the south went and south coast are almost certainly derived from escaped or released captive-bred stock.

 

Information was also collected on reactions to disturbance, caused of mortality, habitat requirements and land class selected in England and Wales. Pressures facing the pine marten population of these countries are discussed and recommendations are made for future actions in terms of survey, research and practical conservation measures.

 

For further information please contact:
Tracking Mammals Partnership co-ordinator 15 Cloisters House, 8 Battersea Park Road, London SW8.