Transparent Burnet Surveys in Argyll in 2012
Andrew Masterman 16 May 2012
Transparent Burnet (Zygaena purpuralis) like the other burnet moths is a striking insect. Instead of
red spots, the Transparent Burnet (TB) sports bars of red on its transparent wings - hence its name.
It used to be called the Oban Burnet owing to its presence at a number of sites close to Oban but it is
also found on the islands of Kerrera, Lismore, Mull, Ulva, Skye, Canna, Eigg and Rhum as well as
some other coastal parts of the mainland in Ardnamurchan and Kintyre. It is locally common in
Counties Clare and Galway in Ireland but this striking moth has not been seen since 1962 in Wales
(Absersoch, Carnarvonshire and Cardiganshire) and is now presumed to be extinct here.
Figure 1 Traransparent Burnet
Credit: Neil Gregory
There is a reasonable understanding of Transparent Burnet ecology but not a lot has been written:
Waring states that both sexes fly in warm weather, preferring sunshine, from early June to July, and
visit nectar flowers such as Wild Thyme (do TB use any other nectar plants?). During dull or wet
weather, they sit about, often fully exposed and wet, on flowerheads or surrounding vegetation,
sometimes for days. Habitat is steep, heathy and grassy south and south-west facing slopes and
under cliffs on or near the coast and very locally inland on limestone. Great fluctuations in
population density have been recorded , sometimes in response to changing grazing levels. There is
one generation a year and it overwinters as a larva, sometimes twice. It pupates in a spun cocoon
concealed near the ground.
Heath and Emmett say of TB “inhabiting steep grassy south-facing slopes and undercliffs on or near
coast, dunes and limestone areas inland.”
The aims of the 2012 survey are to get a bit more detailed information on the habitat of Transparent
Burnet as the terms, heathy and grassy are very vague and the only nectar plant mentioned is Wild
Thyme which is also the larval foodplant. So the key questions are:
1)
2)
3)
4)
Which heath plants comprise TB habitat?
Which grasses comprise TB habitat?
Do other flowering plants occur in TB habitat?
If 3) is true, do TB nectar on these other flowering plants?
Wild Thyme is generally confined to rocky ground/escarpments which is somewhat at variance with
heathy or grassy vegetation. And coastal cliffs are of course rocky. But perhaps TB needs a mosaic of
rocky ground with areas of heath or grass as well. One known site near Oban, Beinn Lora does have
large rocky outcrops where Wild Thyme. There are many small hills near the Argyll coast either side
of the main road from Oban to Lochgilphead which have small rocky outcrops which may possibly
have Wild Thyme and Transparent Burnet. One aim of the 2012 survey is to find new sites as TB is
undoubtedly under-recorded to some extent. So rocky outcrops on hills should be explored and
coastal sites. Lismore has limestone geology so may well provide some limestone habitats of TB but
the last record here is for 1960. The island of Kerrera also has a last TB record for 1960 so it would be
exciting if some 2012 records could be obtained for these two islands which are just a short hop
from the Argyll mainland.
A pro-forma, transparent-burnet-surveys-2012-proforma.doc has been produced to record the
vegetation within a 10 m of a Transparent Burnet observation. TB can be very numerous, so don’t
record lots of data for individuals close together but record data from several different sites within a
colony area. TB sites such as rocky escarpments and sea cliffs can be dangerous places should you
slip so don’t put yourself in danger at such sites: in such cases, don’t attempt to record data within a
10 m radius of a TB seen! TB is a large and conspicuous insect so binoculars can be used to scan
suitable sites for TB and counts noted.
Figure 2 shows the location of all historical TB observations in Argyll and the grid references are
listed in Table 1.
Figure 1 Distribution of historical Transparent Burnet observations in Argyll.
Table 1 Grid references of Transparent Burnet observations in Argyll
Site
Gridref
Date
Recorder
Argyll>Kerrera
NM801268
1960
Unknown
Stage
Argyll>Lismore>Loch Fiart
NM805375
1960
Unknown
Argyll>Loch Feochan>Minard
NM820237
1960
Unknown
Argyll>Oban>Minard>Ardentallan
NM8223
1978
Langmaid, J. & Agassiz, D.
Argyll>Oban>Glen Lonan
NM9128
1984
Hadley, M. & Church, S.H.
Argyll>Oban>Beinn Lora
NM915372
1994
Bourn, N.
Argyll>Glen Lonan>Deadh Choimhead
NM945285
1994
Nigel Bourn
Argyll>Oban>Minard Point
NM817237
21-Jun-82
McCormick, Roy F.
Argyll>Oban>Beinn Lora
NM910373
23-Jun-88
W G Tremewan
Argyll>Loch Feochan>Minard
NM816237
23-Jun-88
W G Tremewan
Argyll>Oban>Loch Nell
NM884276
24-Jun-88
W G Tremewan
Argyll>Glen Lonan,>Deadh Choimhead
NM943286
24-Jun-88
W G Tremewan
Argyll>Glen Lonan>Deadh Chomhead
NM945285
30-Jun-93
Nigel Bourn
Adult
Argyll>Oban>Beinn Lora
NM915372
01-Jul-93
Nigel Bourn
Adult
Argyll>Kerrera
NM801268
02-Jul-93
Nigel Bourn
Adult
Argyll>Oban>Beinn Lora
NM917372
27-Jun-95
David Barbour
Argyll>Oban>Beinn Lora
NM917372
04-Jul-95
David Barbour
Argyll>Oban>Beinn Lora
NM917372
11-Jul-95
David Barbour
Argyll>Glen Lonan>Deadh Chomhead
NM946282
28-Jun-02
John Knowler
Adult
Argyll>Oban>Gallanach
NM827262
30-May-04
Helen Bibby
Adult
Argyll>Oban>Barrandroman
NM842228
22-Jun-04
Jamie Mellor
Adult
Argyll>Oban>Barrandroman
NM842228
25-Jun-04
Jamie Mellor
Adult
Argyll>Oban>Barrandroman
NM846229
25-Jun-04
Jamie Mellor
Adult
Argyll>Oban>Barrandroman
NM842228
20-Sep-04
Jamie Mellor
Adult
Argyll>Oban>Barndromin WGS block
NM846229
26-Jun-05
Jaimie Mellor
Adult
Argyll>Oban>Beinn Lora
NM90843720
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM91413761
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM91683695
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM91803768
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM91883759
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM91883768
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM91903753
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM91903755
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM91903759
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM91983737
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM91983738
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92003735
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92003736
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92013734
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92013735
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92033732
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92043732
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92053732
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92063732
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92093731
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92223702
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92323704
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92343722
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92363721
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92363722
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92403715
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92453714
14-Jun-10
Prescott; Tom
Adult
Argyll>Oban>Beinn Lora
NM92503713
14-Jun-10
Prescott; Tom
Adult
Argyll>Glen Feochan
NM90892425
01-May-11
Olya Maiboroda & Carl Farmer
Larval
Argyll>Glen Feochan
NM90892426
02-May-11
Carl Farmer & Olya Maiboroda
Larval
Adult
Adult