Habitats and abundance of butterflies on agricultural land at Writtle College
Table 5. Numbers of Thymelicus species per 100 metres on the College Transect
The most severe reduction in abundance was displayed by O. venata which preferred the grassy
areas of the College Transect (Table 6) being most abundant in Sections 2 and 8. However, O.
venata was also fairly common in the wooded habitats of Section 4. This species was much reduced
in numbers in every section of the College Transect including the preferred habitats. After five
years of monitoring O. venata had become restricted in limited abundance to only four sections.
Table 6. Numbers of O. venata individuals per 100 metres on the College Transect
Concentrations of butterflies varied substantially between different sections on both transects (Table
7). On the College Transect the preferred habitats were the meadow habitats (Sections 2, 5 and 8).
Section 2 in particular had 21 species over the five years including the notable species A. agestis and
L. phlaeas. Section 4 (woodland area) had 22 butterfly species including the five notable species.
Butterflies tended to be less abundant in the sections of hedgerow and arabic habitats.
Butterflies were concentrated in Sections D, E and H on the Lordships Transect (Table 7). Sections D
and E form part of a green lane habitat, which contains a grassy meadow enclosed by ancient hedgerows.
Butterflies were also fairly abundant on the grassy roadside verge of Section H with three notable
species. Section A (woodland and scrub) is of interest despite a moderate abundance of butterflies
because all five notable species were recorded over the survey period. As noted on the College Transect
butterfly abundance is restricted in areas containing hedgerow, arable and other habitats.
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Essex Naturalist (New Series) 18 (2001)