Fróðskaparrit - 01.01.2005, Qupperneq 141

THE STABLE FLY (STOMOXYS CALCITRANS) (DIPTERA: MUSCIDAE)
RECORDED FROM THE FAROES
139
Fig. 2. Interior from a Faroese byre (Photo: Søren Achim Nielsen).
Mynd 2. Innan í einum Føroyskum íjósi (Mynd: Søren Achim Nielsen).
cies was recorded from five of the byres,
and in two of them (1, 4) it occurred in
considerable densities. All dipteran fami-
lies found in the Faroese byres were pre-
viously recorded from stables in Central
Europe (Kiihlhorn, 1964). No relation
between the abundance of S. calcitrans in
the byres and the number of other dip-
terans was found. This might reflect, that
the dipteran fauna recorded is made up of
species actually hatched in the byres as
well as immigrants from field habitats. In
the sampling period the day temperature
out-of-doors was about 12 °C, permitting
activity of Diptera in the open.
The population dynamics of S. calci-
trans depends on the number of cows in
the byre, the extent and frequency of clean-
ing, and the room temperature (Thomsen,
1938). The stable fly breeds in dead and
decomposing plant material, e.g. in dung
ntixed with straw and urine, especially in
places where bedding accumulates during
a long time. In most of the byres visited
potential breeding media for S. calcitrans
were found.
According to Thomsen (1938) no ovipo-
sition occurs at temperatures below 14-15
°C; at temperatures of about 18 °C the
development frorn egg to adult takes about
a month (Lysyk, 1998). In byres in Den-
mark the air temperature during the winter