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Macrolepidoptera at Kungsmarkens Naturreservat
1999 Report
by Hannu Saarenmaa1
Introduction
The purpose of this study has been to make a comprehensive inventory of
the Macrolepidoptera at Kungsmarkens Naturreservat. The site is located
in Sweden, province of Skåne, municipality of Lund, near the co-ordinates
(WGS-84) N55.43, E013.17. More details of Kungsmarken, including
listings of its flora and bird fauna can be found at Bengt
Jönsson's site.
An additional aim was to investigate differences in fauna between the
various habitats within the area. Information about spatial heterogeneity
in biodiversity may be useful for management of the nature reserve.
Methods
The inventory has been carried out using quantitative methods. Four
light traps were operated throughout the year 1999, and placed in an electric
line 450 meters long (Figure 1). The traps
and the method have been described by Söderman and Tahvanainen (1994).
With minor exceptions, the traps were checked every Sunday.
In addition, three bait traps were operated on an occasional basis.
Weather permitting, line surveys of daytime-active Lepidoptera were
made every Sunday on a standard trail (Figure 1).
Figure 1. Location of the electric
line and the four traps at the northern forested edge of Kungsmarkens Naturreservat
(at distances -30, 0, 50 and 100 meters from the edge). The survey
line for daytime observations is drawn with a thin line.
Material
All observed or caught Macrolepidoptera were identified to the species
and counted to the individual, if possible without examination of genitalia.
Some difficult sibling species were only identified to the species group.
These include Timandra grisea- comai, Mesapamea secalis- secalella,
Amphipoea fucosa- crinanensis- lucens, and Noctua janthe- janthina.
A total of 33983 Macrolepidoptera belonging to 380 species were found.
A total of 1076 specimens were collected. Annex
1 gives a summary listing of the material.
The four light trap sites can be characterised as follows:
-
-30
-
This trap was placed at the outer edge of the "Skogahus" ranch under some
20-year old 15-meter tall poplars. It effectively collected from
the cropfields and the yard.
-
0
-
This trap was placed at the north-western corner of the "Skogahus" ranch
property line over the stony wall that separates the cropfields from the
mixed oak and elm forest.
-
50
-
This trap was within a 60-year old oak (Quercus robur) stand at
the corner of the measurement plot 807 of the Swedish University of Agricultural
Sciences. Understory vegetation was very dense, blocking the light
to most directions.
-
100
-
This trap was placed next to some smaller linden trees (Tilia cordata)
in a mature birch (Betula pendula) stand. It was about 10
meters from the edge of a swampy alder (Alnus gluteosa) stand and
about 40 meters from the oak stand and plot 807. There were no obstacles
to the light.
The bait traps were operated at the northeastern edge of the forest.
All the material was saved in a Microsoft Access 97 database.
Results
Figure 2 shows the distribution of the material in the four light traps.
More parameters of the catches are given Table 1. Not surprisingly,
the largest catches came from the forest edge. The smallest numbers
were in the oak stand, obviously because the light did not penetrate very
far from that location.
Figure 2. Macrolepidopteran species
numbers and abundance in light trap catches at four different distances
from forest edge (meters, negative number denoting outside forest) at Kungsmarkens
Naturreservat, Sweden, Skåne, Lund, in 1999.
Table 1. Numbers of species, individuals
and proportions of light total light trap catches.
|
|
Number of Species
|
Number of Individuals
|
Proportion of Total Number of Individuals
|
Number of Species only on this Site
|
Number of Typical Species at 5% Risk
|
|
-30
|
261
|
4397
|
0.141944
|
18
|
36
|
|
0
|
290
|
11399
|
0.367983
|
23
|
55
|
|
50
|
248
|
5887
|
0.190044
|
11
|
48
|
|
100
|
267
|
9294
|
0.300029
|
14
|
34
|
|
Bait Traps
|
57
|
544
|
|
1
|
|
|
Daytime Observations
|
38
|
2313 (approximate sighting figures included)
|
|
|
|
The distribution of moth species between different sites was tested
using the following hypothesis: There is no difference between the share
of a site of the total catch over all sites and the share of the catch
of a single species on a site of the total catch of that species.
According to the hypothesis, a species has no difference in abundance between
the sites as such. The differences are only due to the general suitability
of the site for the moths. The species which do not conform to this hypothesis
either are relatively more abundant on a particular site (typical species
to that site) or are relatively less abundant (untypical species to that
site). The hypothesis was tested by using the binome distribution quantity
where
-
P is the share of the catch on the site of the total catch of the
species,
-
p is the share of the total catch on the site of the total catch
on all sites,
-
q = 1 - p, and
-
n is the total catch of the species on all sites.
This test quantity is normally distributed when np>5 and nq>5.
Species were included in the list of species typical to the site (see the
annexes), if the binome distribution quantity was statistically significantly
different from zero at 0.1% risk. Numbers of species typical at 5%
risk were also counted for Table 1. In addition, species only found
at each site were listed.
Annex 2, annex
3, annex 4, and annex
5 give the species typical to the sites -30, 0, 50, and 100, respectively.
In general, the differences between the four sites were quite profound.
Site -30 was mainly characterised by the presence of poplar-feeding species.
Both sites -30 and 0 captured species from cropfields. Site 50 was
dominated by oak-feeders, which were also common at site 0. Site
50 had a relatively large number of typical species despite of its small
catches. Site 100 was characterised by birch- and alder-feeders.
A few rare species were observed. Scopula nigropunctata
was captured at site 50 between 19-24 July 1999. This was the 3rd
specimen fro Sweden of this species that is red-listed in Denmark (Figure
3). Because it occurred in the midst of a dense oak forest habitat
typical to it, it could be a local inhabitant. Other interesting
species include Cupido minimus, Drepana binaria, Cymatophorima diluta
(the second most abundant species), Perizoma sagittata, Chloroclystis
v-ata, Hypomecis punctinalis, Pelosia muscerda, Deltote bankiana, Nola
albula, Trachea atriplicis, Photedes extrema, Xylena exsoleta,
och
Eriopygodes imbecilla.
Discussion
The current study probably gave an almost full picture of species living
in the forest of Kungsmarken. All the major habitats therein were
covered.
The results should be interpreted to describe the habitats. Making
conclusions about distance from the edge would require several replications
of the line, and at different stands.
For future studies, the oak habitat could be resampled again in a site
allowing a better dispersion of light. Elevating a trap over 5 meters
high might also reveal something new. A light trap should also be
placed at the pasture south of the forest, and on the slope falling to
Glomsjön. Also more bait traps could be used. One species,
Xanthia
gilvago, was now observed only with bait.
Daytime observations produced only a limited number of species as the
dense forest does not host may butterflies. Unquestionably, longer
excursions in near the golf course and Glomsjön would reveal more
species. Search and rearing of larvae could also give a better picture.
Reference
Söderman, G. & Tahvanainen, P. 1994. Moth monitoring scheme.
Environmental Report 8, 63 p. National Board of Waters and Environment,
Helsinki.
Acknowledgement
This study was carried out with the permission 231-5609-99 of Länstyrelsen
i Skåne län.
Contact Information
Hannu Saarenmaa,
Skogahus, Östra Odarslöv 171, S-22592 Lund, hannu@bioshare.com.
Comments, questions, corrections and additions are welcome.
Last updated 2000-04-20.
For current records, see http://www.bioshare.net/places/site/kungsmarken/
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