Habitats and abundance of butterflies on agricultural land at Writtle College
Declines in butterfly abundance were in evidence in several of the transect sections (Table 3). The
major grassland areas on the two transects have shown dramatic reductions in butterfly numbers
with the most notable declines being in Sections 2, 5, 8 on the College Transect and D and H on the
Lordships Transect. Sections containing predominantly hedgerow, arable or grazed habitats sustained
more stable butterfly populations exemplified by Sections 3, 7, B and G. However, two hedgerow
areas (Sections C and E) did experience declines in numbers.
Table 3. Number of individuals per 100 metres per year on
selected sections of the College and Lordships Transects
These declines in butterfly abundance were reflected by individual species such as Small Tortoiseshell
Aglais urticae, Thymelicus species and Large Skipper Ochlodes venata which experienced declines
in the numbers of individuals per visit over the monitoring period (Figure 2).
Fig. 2. Number of individuals per visit for A. urticae, Thymelicus species and O. venata
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Essex Naturalist (New Series) 18 (2001)