Fróðskaparrit - 01.01.2008, Blaðsíða 170

168
DISTRIBUTION AND THE IMPACT OF OUTFIELD DRAINACE ON CARABIDS
(■COLEOPTERA, CARABIDAE) IN NORTH WESTERN EYSTUROY, FAROE ISLANDS
UD-AREA (Eiði 2)
Above 125 altitude Below 125 altitude First part of season Later part of season
Date: 24 July & 3, 22, 23-aug-2007 N=42 Date: 24 July & 3, 22, 23-aug-2007 N=56 Date: 24 July & 08-aug-2007 N=65 Date: 22 & 23-aug- 2007 N=33
Number of indi- viduals Percent- age abun- dance(%) Number of indi- viduals Percent- age abun- dance (%) Number of indi- viduals Percent- age abun- dance(%) Number of indi- viduals Percent- age abun- dance (%)
Agonum fuliginosum 0 0.0 0 0.0 0 0.0 0 0.0
Bembion bruxellense 0 0.0 1 0.1 1 0.0 0 0.0
Calathus fuscipes 48 4.9 141 25.9 153 17.0 36 7.9
Calathus melanocephalus 1 0.1 24 2.8 25 1.9 0 0.0
Carabus problematicus 50 5.3 60 10.8 51 4.8 59 13.4
Loricera pilicornis 1 0.1 2 0.4 3 0.3 0 0.0
Nebria rufescens 74 9.2 17 4.3 73 8.5 18 4.4
Nebria salina 287 38.8 107 22.2 204 26.1 190 42.7
Notiophilus biguttatus 35 7.3 13 4.7 24 3.7 24 11.0
Patrobus atrorufus 48 10.7 36 10.8 64 13.2 20 6.0
Patrobus sepentrionis 57 11.5 16 6.2 64 12.6 9 2.5
Pterostichus adstrictus 5 1.4 7 1.5 10 1.4 2 1.3
Pterostichus diligens 1 0.4 4 0.7 3 0.7 2 0.3
Pterostichus nigrita 7 2.1 23 7.1 13 3.1 17 6.5
Trechus obtusus 49 8.2 16 2.6 46 6.7 19 4.0
SUM 663 100.0 467 100.0 734 100.0 396 100.0
Table 3. Numbers and percentile abundance of carabidae collected in UD area. Data are presented
according to altitude and part ofseason. N referes to the number of stations, each containing 5 pitfall
traps.
formed numbers. Data were separated ac-
cording to season and altitude. This was
done because the vegetation and tempera-
ture change from lowest to highest altitude
and carabidae have different preferences re-
garding vegetation and temperature (Lind-
roth, 1985; 1986 and Thiele, 1977). Carabidae
also have different activity peaks which usu-
ally are associated with reproduction (Lin-
droth, 1985; 1986 and Thiele, 1977). There-
fore data were divided between early part of
the season and late part of season. The data
was divided so that N was distributed as
equally as possible between later and earlier
part of season and between altitudes, see Ta-
bles 2, 3 and 4. As the data could not be
transformed into a normal distribution, non-
parametic analyses were performed. Differ-
ences in altitude and seasonality were tested
by Mann-Whitney test, while when compar-