Wildlife and Conservation Review of 2000
in 1974; significant though this is, it is in fact a lower rate than many counties - Northamptonshire,
for example, lost 93 species in 61 years, and Lincolnshire, Gloucestershire and Middlesex all lost
about one species a year on average.
The losses are ascribed to numerous factors, but most particularly habitat loss, poor management,
and increasing fertility. These were also amply demonstrated by the results of the Countryside
Survey 2000, the culmination of a £4 million, four-year project based on the detailed sampling of
selected 1km squares around the country. The results paint a worrying picture of general habitat
change, albeit showing greater stability since 1990 than in previous decades. Habitat destruction has
slowed, but other more insidious changes were noted: the widespread evidence of nutrient enrichment
with taller, more competitive species spreading at the expense of lower-growing, stress-tolerant and
often more interesting plants. There were, however, some positive messages as well: broad-leaved
woodland has increased, along with ponds, hedgerows and improvement in quality of small
watercourses.
Important scientific observations of relevance to our countryside and wildlife can of course come
from many sources - from large-scale, resource-intensive surveys as above to the detailed observations
of one or two observers. Some excellent examples of the latter come from Chris Mason and Sheila
Macdonald looking at the Tendring Peninsula, where they studied the population/habitat
relationships of declining farmland and urban birds; the results were published towards the end
of the year. Their study of Corn Buntings located 278 territories in the area, more than 2% of the
current UK population. At densities of up to 7.5 per square kilometre, Tendring appears to hold one
of the most dense populations in Europe. But significantly, there was evidence of some decline
during the five years of survey work. During the breeding season, their habitat preferences were
unclear, though there was some suggestion that they avoid fields with hedges, that song posts are
important, and territories are more likely to contain water-filled ditches and/or weedy farm tracks
than would be expected statistically. In winter, success is related to the availability of small grassed
areas (before New Year) and stubbles (after New Year).
A second paper looked at a wider range of species in the same area. More than half of all Skylarks
were found in autumn-sown cereals (not surprising given the predominance of this habitat), but
densities were higher in set-aside and spring-sown crops, and greatest in 'conservation grassland'.
They were also negatively associated with hedgerows. Yellow Wagtails showed a preference for
spring-sown crops, especially potatoes, and larger fields; Linnets with scrub and in winter Oil-seed
Rape; Whitethroats with hedges; Lesser Whitethroats and Yellowhammers with tall hedges; and
Turtle Doves with residential areas, scrub and woodland. Some of these findings are perhaps pretty
obvious to a keen observer, but the more subtle factors do help to inform urgently-needed conservation
action.
The third study looked at Blackbirds, Song and Mistle Thrushes in urban and adjacent rural areas
radiating west and south from Harwich. Significantly more territories than expected of all species
were within the urban boundary. Within the rural parts of the study area, amounting to 67% of the
total, the fewer Blackbird and Mistle Thrush territories than expected were mostly associated with
the small amounts of grass, and Song Thrushes were simply not present. This serves to reinforce the
relative value of our immediate surroundings, which has clear implications both for the way we
manage our gardens and for planning control decisions, for example in the debate about brownfield
versus greenfield housing as discussed earlier.
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Essex Naturalist (New Series) 18 (2001)