Spider Biodiversity Potential of an Ungrazed and a Grazed Inland Salt

Biodiversity and Conservation 6, 75±88 (1997)

Spider biodiversity potential of an ungrazed and a grazed inland salt meadow in the National Park `Neusiedler See-Seewinkel' (Austria): implications for management (Arachnida: Araneae)

KLAUS PETER ZULKA*, NORBERT MILASOWSZKY and CHRISTA LETHMAYER Institute of Zoology, University of Vienna, Althanstr. 14, A-1090 Vienna, Austria

Received 7 June 1995; revised and accepted 20 November 1995

To assess the biodiversity potential of an ungrazed and a grazed inland salt meadow in the Seewinkel (Eastern Austria), spider assemblages were recorded by pitfall trapping for 1 year. Both species assemblages consisted, to a large extent, of rare species of conservation interest. The species assemblage of the grazed site was dominated by Pardosa agrestis, but highly speci®c halotopobiontic species also occurred in higher numbers. Halotolerant species were also present in the ungrazed meadow, but their individual number was much lower. The species composition of this site re¯ects the more balanced microclimatical situation of the high sward. Comparison of the two assemblages with 207 other meadow spider assemblages of Central Europe shows a separated position, especially of the grazed site assemblage. High similarities with assemblages of meadows with a similar vegetation structure indicate a high importance of management. Considering the high proportion of rare species on both sites, the best management of the salt meadow and pan shores of the Seewinkel should combine areas of light grazing with ungrazed areas. However, the proportion of these parts and the intensity of grazing still remains to be determined by quantitative experiments. Keywords: grazing; pasture; halophily; conservation; similarity index.

Introduction The loss of biological diversity due to human impact is a ubiquitous phenomenon in the 20th century (e.g. Ehrlich and Ehrlich, 1981). However, not all biotopes are equally af- fected by this decline, and not all kinds of biotopes are equally important for the main- tenance of biodiversity. Inland salt sites are probably among the most sensitive and the most signi®cant sites in this respect. They usually house a specialized fauna and ¯ora of tolerant species (or locally adapted populations). Salt sites are often very small, isolated and patchily distributed, which implies all problems of extinction probability analysed by island ecology (Sim- berlo, 1988; Saunders et al., 1991). They are often surrounded by highly managed or polluted agricultural land. A small change in management practice or hydrology, e.g. lowering of the groundwater table, can lead to a complete disappearance of the typical

*To whom correspondence should be addressed. 0960-3115 Ó 1997 Chapman & Hall 76 Zulka et al. fauna and ¯ora; even if they are left physically intact (e.g. MuÈller-Motzfeld et al., 1993). Consequently many species lists in Red Data Books consist, to a large extent, of halotopobiontic species (e.g. MuÈller-Motzfeld, 1987; JaÈch, 1994). The `Seewinkel', the area between Neusiedler See and the Hungarian border (Eastern Austria), is probably the most important region of inland salt sites in Central Europe. About 6% part of the soils of the Seewinkel contain high amounts of soda (Nelhiebel, 1980). However, since the turn of century the number of alkaline pans has declined dramatically from 116 (LoÈer, 1982) to about 40 today. Even the remaining ones are often in a poor condition. When, in 1994, the National Park `Neusiedler See-Seewinkel' was established, large parts of the alkaline pan areas became included. Clearly, not all conservation problems can be solved simply by declaring a national park (Herzig, 1991). One threat for the typical landscape is the spread of reed vegetation, overgrowing the alkaline pans and the Puccinellia peisonis meadows around them. Fes- tetics (1970) described the negative eects of too low grazing rates, leading to a trans- formation of the original and typical salt pan shores into the swampland of much lower conservation value, especially for birds. Thus, in 1988 a grazing programme was established at the `Illmitzer Zicksee' to reduce the negative in¯uence of the growing reed cover (Rauer and Kohler, 1990) and to enlarge the breeding area for birds. However, grazing might have a negative in¯uence on epigean arthropods. Many animal groups reach much higher population densities in ungrazed meadows (Morris, 1968). The spider fauna of an intensively grazed pasture was shown to be impoverished compared to the margin and consisted mainly of widespread pioneer species (Maelfait and de Keer, 1990). All spider species requiring more complex vegetation structures (e.g. web-formers) are signi®cantly reduced by grazing (Gibson et al., 1992). Thus, the main aim of this study was the assessment of the faunal potential of a short- grass versus an ungrazed salt meadow. Previous work on the terrestrial invertebrate fauna of the Seewinkel area is very limited, but earlier studies have already indicated that these salt habitats house highly speci®c arthropod communities (Machura, 1935; Franz et al., 1937; KuÈhnelt, 1955; Kritscher, 1958; Nemenz, 1958).

Materials and methods Study area The study area comprises two meadows situated about 10 km North-West of Illmitz (47ë46¢N, 16ë46¢E) near the `Illmitzer Zicksee' salt pan. The unmanaged meadow covers an area of about 110 ´ 50 m and lies at 117 m above sea level. It is sharply bordered by vineyards on two sides and indistinctly by invading reed vegetation on the other two sides. Both pitfall trapping and vegetation analysis (Table 1) were performed in the centre of the meadow. The managed meadow lies about 1100 m apart (height 116 m, area 0.2 ha). It is surrounded by introgressing reed vegetation on one side, vineyards on two sides and a road. Grazing started in 1989 with ¯uctuating intensity (0.1±0.5 cows ha)1). In 1990, the year of study, the meadow was extensively grazed from May to October by about 0.8 cows ha)1 (Aberdeen-Angus) (cf. Rauer and Kohler, 1990; Lethmayer, 1992). Soil conditions and vegetation composition of the two sites are fairly similar: both lie on solonchak soda soils and both meadows are dominated by Puccinellia peisonis (Table 1), being a part of the endemic Atropidetum peisonis (Franz et al., 1937) plant association Spider biodiversity and management 77 Table 1. Vegetation at the two sites

Ungrazed Grazed Area of vegetation sample (m2)2520 Vegetation cover (%) 100 75 Maximal vegetation height (cm) 70 20 Average vegetation height (cm) 50 20

Species Covera

Puccinellia peisonis 54 Suaeda maritima 1 Odontites rubra 1 Achillea millefolium + Aster tripolium ssp. pannonicus 2+ Atemisia santonicum ssp. patens + Lepidium cartilagineum ++

aAccording to Braun-Blanquet (1964).

(Mucina et al., 1993). However, the structure of the vegetation is completely dierent. The vegetation cover in the grazed meadow is incomplete due to trampling, which allows additional plant species to enter the habitat (e.g. a small patch of Lepidium cartilagineum, Table 1). The sward is uniformly short, leading to high insolation, evaporation and salt incrustations on the soil surface. Thus, microclimatical conditions are much more extreme than within the homogeneous sward of the ungrazed meadow (cf. Lethmayer, 1992)

Sampling methods Spiders were sampled using ®ve pitfall traps at each site (plastic cups with a diameter of 7 cm and a height of 10 cm, covered with a tin roof, half-®lled with 5% formalin and containing a small amount of detergent). The traps were arranged in a quadrate with one trap in the centre (cf. Lethmayer, 1992). Pitfall trapping was conducted from 9 April to 26 October 1990. The traps were emptied at exact 10-day intervals. The contents of all ®ve traps were pooled and stored in 70% ethanol.

Analysis The two spider assemblages obtained were compared to a set of 207 other Central Eur- opean assemblages from the literature. Most assemblages came from grassland, but some came from agricultural land and wetland formations. All assemblages had been sampled by pitfall trapping during at least one complete vegetation period. Two similarity indices were used: Sùrensen's quotient, comparing only presences and absences, and Renkonen's coecient of similarity, taking also dominance (percentage of total individuals) into account (MuÈhlenberg, 1989, p. 287). However, for the comparison by Renkonen's index 13 assemblages had to be excluded from the analysis because no exact individual numbers were given in the publications. 78 Zulka et al. Results Species composition A total of 4742 adult individuals was caught, about two thirds of them in the grazed meadow (Table 2). The species number was slightly higher on the grazed plot, the a-diversity value (as measured with the Brillouin index, Magurran, 1988) slightly lower. Of 85 species, 31 occurred on both sites, resulting in a Sùrensen quotient of similarity of 0.53 (Table 4). Only four species (Ozyptila simplex, Pardosa prativaga, Alopecosa pulverulenta and Trochosa ruricola) occurred on both sites with dominances >1% (Table 2). Thus, even

Table 2. Dominant species of both sites and assemblage parameters of the full data set

Species Site Number of Dip Signi®cance a Ungrazed Grazed peaks of intensity male activity

Pardosa prativaga (L. Koch) 37.51% 2.23% 1 Pirata latitans (Blackwall) 9.71% ± 1 Pocadicnemis juncea Locket & 8.24% 0.09% 1 Millidge Syedra apetlonensis Wunderlich 6.71% 0.13% 2 1.68 p >0.5 Drassyllus lutetianus (L. Koch) 5.11% 0.38% 1 Trochosa ruricola (De Geer) 4.73% 1.70% 1 Trichopterna thorelli (Westring) 2.49% ± 1 Pardosa maisa Hippa & Mannila 1.67% ± 1 Clubiona subtilis L. Koch 1.53% 0.28% ? Zelotes latreillei (Simon) 1.47% 0.09% ? Micrargus subaequalis (Westring) 1.15% ± 1 Pardosa agrestis (Westring) 0.26% 46.64% 2 3.00 p > 0.01 Ozyptila simplex (O. P.-Cambridge) 8.56% 17.66% 1 Silometopus reussi (Thorell) ± 8.15% 2 4.59 p > 0.01 Zelotes mundus (Kulczynski) ± 5.35% 1 Alopecosa pulverulenta (Clerck) 1.02% 2.08% 1 Pardosa cribrata Simon ± 1.64% 1 Xerolycosa miniata (C. L. Koch) ± 1.45% 1 Arctosa lutetiana (Simon) 0.77% 1.01% 1 Total number of individuals 1565 3177

Assemblage parameters Species number (S) 56 59 Number of individuals (N) 1565 3177 Brillouin index of diversity 2.38 2.07 Rare species (%) 21.43 22.03 Individuals of rare species (%) 15.02 9.41 Halophilic species (%) 5.36 6.68 Individuals of halophilic species (%) 0.19 7.43 Individuals of pioneer species (%) 0.38 47.81 aAccording to the dip intensity test (Giacomelli et al., 1971). Spider biodiversity and management 79 if the assemblages of the two plots are comparable regarding their qualitative composition, the quantitative similarity is low (Renkonen's coecient 0.19, Table 4). Nearly half of the catch in the grazed meadow consisted of Pardosa agrestis (Table 2). The species is typical for open agriculturally managed land (e.g. Thaler et al., 1987) and has a high colonization potential (Lamparski et al., 1990). Other typical pioneer aero- nauts, such as Meioneta rurestris and Erigone atra, were also con®ned mostly to the managed site, but occurred in low numbers there. The ungrazed site is characterized by a number of hygrophilous species preferring damp microclimatical situations (e.g. Trichopterna thorelli, Drassyllus lutetianus, Pocadicnemis juncea, Table 2). Both assemblages contain a high proportion of species which can be considered as rare on the basis of their records in the Austrian literature (Zulka, unpublished database). Mostly, only a few individuals of these species were caught, but highly typical species, such as Syedra apetlonensis or Pardosa cribrata, were caught quite abundantly. These species are, according to the present state of knowledge, restricted to the Seewinkel region within Austria. The percentage of halotopobiontic species is about 5% on both sites, but species of this group were caught on the grazed site in much higher individual numbers (Table 2). This is especially true for Zelotes mundus, a species that is restricted to the inner zones of the alkaline pans (Milasowszky and Zulka, unpublished). The short-grass meadow also houses elements such as Silometopus reussi or Argenna patula, which occur elsewhere predominantly in coastal habitats.

Phenology According to general theories of habitat stability and life cycle strategies (Southwood, 1988), species of the grazed plot rather than from the ungrazed should be expected to be multivoltinous. We found a bimodal phenology curve of the males, which suggests two generations, in three species (Table 2). However, only in two dominant species of the grazed plot, Silometopus reussi and Pardosa agrestis, was bimodality signi®cant, as revealed by Kruskal's dip intensity test (Giacomelli et al., 1971). In P. agrestis the ®rst maximum of male activity was from 29.4.90 to 9.5.90, the second from 8.7.90 to 18.7.90; in Silometopus reussi the ®rst maximum was in early April, the second at the end of June.

Coenological comparison The comparison of the ungrazed meadow assemblage with other Central European grassland spider assemblages shows high similarities with other unmanaged or lightly managed meadow types (Table 3). However, the highest qualitative similarity, as measured by Sùrensen's quotient, exists between the two investigated assemblages, suggesting their rather endemic character. High quantitative (Renkonen's coecient) similarity is shown with spider assemblages of wet or periodically ¯ooded swamp meadows with a high sward (Table 3). The spider fauna of the grazed plot shows the highest qualitative similarity with another grazed (but dry) meadow from the same region, again underlining the regional speci®city of the faunal composition (Table 4). Anities are also high with agricultural, disturbed, pioneer or short-grass sites. Quantitative similarities, as measured by Renkonen's coecient, of this assemblage are quite low (Table 4), indicating an isolated position of this assemblage. The highest values 80

Table 3. Similarities of spider assemblage of the ungrazed meadow with other meadow assemblages of Central Europe

Similarity according to Sùrensen's quotient (only the seven assemblages with highest similarities are listed) Index Habitat Locality Reference 0.534 Grazed meadow A, Seewinkel, lllmitz This study 0.407 Molinietum, cutting every 2±3 years CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 4 0.404 Extensively used meadow on peat CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 27 0.400 Molinietum, cutting every 2 years CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 9 0.400 Moist meadow, extensively grazed CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 26 0.400 Border between reed and Phalaris vegetation CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 28 0.397 Typha reed along a pond bank CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 29

Similarity according to Renkonen's coecient (only the seven assemblages with highest similarities are listed) Index Habitat Locality Reference 0.535 Reed swamp CZ, Lednice, Nesyt ®shpond Miller and Obrtel (1975) 0.486 Disturbed border of a reed swamp, CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 31 sometimes ¯ooded 0.328 Swampy meadow CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 4 0.283 Poorly covered deposit, disturbed meadow CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 11 0.278 Moist meadow, extensive use as a pasture CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 26 0.266 Bank of a pond CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 20 0.266 Reed swamp CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 24 Zulka tal. et pdrboiest n management and biodiversity Spider

Table 4. Similarities of spider assemblage of the grazed meadow with other meadow assemblages of Central Europe

Similarity according to Sùrensen's quotient (only the seven assemblages with highest similarities are listed) Index Habitat Locality Reference 0.534 Ungrazed plot A, Seewinkel, lllmitz This study 0.516 Grazed pasture A, Seewinkel, Apetlon Malicky (1972) 0.440 Bank of a pond, on peat CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 15 0.420 Slope of a channel, border between pioneer CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 17 and reed vegetation 0.412 Arti®cial meadow CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 10 0.407 Moist meadow, extensively used, on peat CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 27 0.404 Poorly covered deposit, disturbed meadow CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 11

Similarity according to Renkonen's coecient (only the seven assemblages with highest similarities are listed) Index Habitat Locality Reference

0.346 Wheat ®eld A, Rinn near Innsbruck Thaler et al. (1987) 0.319 Slope of a channel, border between CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 17 pioneer and reed vegetation 0.253 Deposit, dry and sandy plain, sparse ruderal vegetation D, Berlin, Tierpark von Broen (1986) 0.198 Slope of a rivulet bank, reed meadow CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 18 0.188 Ungrazed plot A, Seewinkel, Illmitz This study 0.170 Border between pioneer and reed vegetation CH, Biel-Neuenburg-Kerzers, Grosses Moos HaÈnggi (1987), site 16 0.157 Dry meadow margin (Brometum) A, Steinfeld near Wiener Neustadt, Malicky (1972) Obereggendorf 81 82 Zulka et al. are reached by highly disturbed open sites. This may be a result of the predominance of Pardosa agrestis in such sites. Similarities with coastal salt marshes (Schaefer, 1970) are low for both meadow types and similarity indices.

Discussion There is a considerable bulk of literature warning of the pitfalls of pitfall trapping as an unsuitable method for the assessment of species abundances (e.g. Adis, 1979; Topping and Sunderland, 1992). Owing to dierent degrees of activity, no inferences can be made on the density between species. Moreover, catch rates are aected by habitat structure. For ex- ample, higher catch rates in the grazed meadow must be attributed to a large part to the lower spatial resistance and cannot be taken as an indication of higher population densities or biomass in the grazed sites. In fact, studies conducted with `absolute' methods lead rather to the opposite relationships (reviewed in Kajak, 1980), as presented here. Fur- thermore, spiders of higher strata are under-represented or are absent in the pitfall catches. Methods taking into account these strata probably would have revealed a much more pronounced diversity reduction due to grazing, especially with regard to large web-spin- ners (Gibson et al., 1992). Sweepnet catching was done several times (Lethmayer, 1992), but most individuals obtained were juveniles, so the data have not been taken into account for this presentation. In addition to the limits of the method, there are limits of the design: `No one would now dream of testing the response to a treatment by comparing two plots, one treated and the other untreated' (Fisher and Wishart, 1930). Evidently, without any replication of treatments (Hurlbert, 1984), as in the present investigation, no general inference on the eect of grazing is possible. However, such studies already exist (e.g. Gibson et al., 1992). Furthermore, the meta-analytical comparison of the two plots with 207 other Central European grassland spider assemblages (Tables 3 and 4) may compensate to some extent for this lack of replication and help the interpretation of the dierences. Such comparisons show high similarities of the grazed meadow and other managed grasslands. Some types of management can lead to extremely impoverished assemblages (e.g. Lu and Rushton, 1989), comprising only a few widespread trivial species. However, only the smaller part of the Seewinkel grazed plot fauna is responsible for such similarities, the other consisting of highly speci®c salt-tolerant species. Furthermore, the assemblage of the grazed plot is not just an impoverished version of the ungrazed meadow assemblage (cf. Gibson et al., 1992), but shows a very dierent dominance structure. However, large short-grass areas or areas with poor vegetation can be found in the whole Seewinkel region, especially in the littoral zone of the alkaline pans as a result of salt in¯uence. Moreover, places grazed by geese are widespread. Thus, even if short-grass salt meadows are restricted to the Seewinkel region, they comprise large areas here. Conse- quently, if conservation eorts were successful to maintain natural short-grass areas, a further increase by grazing seems unnecessary. In contrast, the ungrazed meadow is less typical for the region, but, as faunal comparisons indicate, it is also a rare type of habitat on a larger European scale. Both types of meadow contain a high percentage of rare and typical species, and both types are of high conservation value, yet for dierent reasons. Clearly, the best management should conserve a mosaic of grazed and ungrazed structures (cf. Morris, 1968). This Spider biodiversity and management 83 can be accomplished by grazing of limited patches or by extensive grazing over larger areas because extensive grazing will maintain the structural heterogeneity of the sward (de Keer et al., 1989). The aim of a combination of ungrazed and lightly grazed areas agrees with the recommendation in Ovesen (1990) on the management of coastal salt marshes (reviewed in Bakker et al., 1993). It is also in accordance with results obtained on other groups of animals (Carabidae, Staphylinidae, Chloropidae, Orthoptera), in the same area (Lethmayer, 1992). The conclusions also agree with the `intermediate disturbance hypothesis' (Connell, 1978; Huston, 1979), proposing that the maximal species diversity is reached between the extremes of high stress/disturbance in¯uences and complete stability of the habitat. However, the optimum grazing intensity has to be assessed in replicate studies over the complete area in question with exact quanti®cation of the grazing impact. Other important variables are the optimum size of the grazed areas and the degree of fragmentation of the ungrazed areas. Considering the importance of proper grazing management for the region, we urgently recommend such a study.

Acknowledgements The study was ®nancially supported by grants from the AGN (Arbeitsgemeinschaft Neusiedlersee), the Austrian Ministry of Science, the Federal Government of Burgenland and the Theodor-KoÈrner-Fonds. We are grateful to H. F. Paulus for providing working facilities, to A. Traxler for vegetation reÂleveÂs, to G. Pass for remarks on a previous draft of the manuscript, to K. Thaler and E. Bauchhenss for revision of some specimens and comments on the species list, to J. Gruber for literature information, to C. Kampichler for advice on bimodality testing and to an anonymous reviewer for valuable suggestions.

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Number Species Site Statusa

Ungrazed Grazed m/f m/f b Mimetidae 1 Ero cambridgei Kulczynski 0/1 F 2 Ero furcata (Villers) 0/2 Theridiidae 3 Crustulina sticta (O. P.-Cambridge) 1/0 1/0 R, H, F 4 Enoplognatha mordax (Thorell) 1/0 R, H, F Linyphiidae 5 Araeoncus humilis (Blackwall) 0/1 2/0 P 6 Bathyphantes gracilis (Blackwall) 1/0 P 7 Ceratinella brevipes (Westring) 0/4 8 Ceratinella brevis (Wider) 1/0 2/0 9 Ceratinopsis stativa (Simon) 6/1 10 Diplostyla concolor (Wider) 5/1 11 Erigone atra Blackwall 18/1 P 12 Erigone dentipalpis (Wider) 0/1 8/1 P 13 Gongylidiellum murcidum Simon 3/1 14 Lepthyphantes pillichi Kulczynski 0/1 15 Meioneta mollis (O. P.-Cambridge) 1/0 8/2 16 Meioneta rurestris (C. L. Koch) 5/1 P 17 Micrargus subaequalis (Westring) 15/3 18 Pocadicnemis juncea Locket & Millidge 76/53 3/0 19 Porrhomma microphthalmum 1/0 (O. P.-Cambridge) 20 Prinerigone vagans (Audouin) 4/0 21 Silometopus bonessi Casemir 2/0 1/0 R, F 22 Silometopus elegans (O. P.-Cambridge) 1/0 23 Silometopus reussi (Thorell) 112/147 (H) 24 Syedra apetlonensis Wunderlich 83/22 0/4 R 25 Tallusia experta (O. P.-Cambridge) 0/3 26 Tallusia vindobonensis (Kulczynski) 2/2 R 27 Tapinocyba insecta (L. Koch) 0/2 28 Trichopterna thorelli (Westring) 14/25 R, F 29 Walckenaeria alticeps (Denis) 0/2 30 Walckenaeria atrotibialis 1/0 (O. P.-Cambridge) Tetragnathidae 31 Pachygnatha clercki Sundevall 0/1 32 Pachygnatha degeeri Sundevall 6/3 18/12 Lycosidae 33 Alopecosa pulverulenta (Clerck) 4/12 56/10 34 Arctosa ®gurata (Simon) 1/0 R 35 Arctosa leopardus (Sundevall) 1/0 20/11 36 Arctosa lutetiana (Simon) 11/1 26/6 37 Aulonia albimana (Walckenaer) 11/1 16/4 Spider biodiversity and management 87 Appendix: (Continued)

Number Species Site Statusa

Ungrazed Grazed m/f m/f b

38 Lycosa singoriensis (Laxmann) 0/1 R 39 Pardosa agrestis (Westring) 3/1 1100/382 P 40 Pardosa cribrata Simon 31/21 R, H 41 Pardosa maisa Hippa & Mannila 16/10 R, F 42 Pardosa palustris (Linnaeus) 10/6 43 Pardosa prativaga (L. Koch) 280/307 59/12 44 Pardosa proxima (C. L. Koch) 7/0 R 45 Pardosa pullata (Clerck) 3/4 1/0 46 Pirata latitans (Blackwall) 118/34 47 Pirata piraticus (Clerck) 1/0 48 Trochosa ruricola (De Geer) 59/15 43/11 49 Xerolycosa miniata (C. L. Koch) 28/18 Hahniidae 50 Antistea elegans (Blackwall) 3/8 51 Hahnia nava (Blackwall) 2/0 Dictynidae 52 Argenna patula (Simon) 1/0 12/1 H, F 53 Argenna subnigra (O. P. -Cambridge) 2/0 54 Dictyna arundinacea (Linnaeus) 0/1 Liocranidae 55 Agraecina striata (Kulczynski) 11/1 Clubionidae 56 Clubiona diversa O. P. -Cambridge 6/8 57 Clubiona neglecta O. P. -Cambridge 0/1 58 Clubiona subtilis L. Koch 11/13 6/3 R Gnaphosidae 59 Drassodes pubescens (Thorell) 3/0 3/0 60 Drassyllus lutetianus (L. Koch) 62/18 10/2 61 Drassyllus prae®cus (L. Koch) 0/1 4/0 62 Drassyllus pusillus (C. L. Koch) 2/2 5/0 63 Haplodrassus dalmatensis (L. Koch) 1/2 64 Haplodrassus minor (O. P. -Cambridge) 9/3 23/5 R 65 Haplodrassus signifer (C. L. Koch) 10/3 66 Micaria romana L. Koch 6/2 R, F 67 Trachyzelotes pedestris (C. L. Koch) 2/2 9/4 68 Zelotes electus (C. L. Koch) 1/1 69 Zelotes latreillei (Simon) 12/11 3/0 70 Zelotes longipes (L. Koch) 1/0 13/0 71 Zelotes mundus (Kulczynski) 116/54 R, H Zoridae 72 Zora armillata Simon 9/4 R, F Philodromidae 73 Thanatus arenarius Thorell 1/0 7/1 R 74 Thanatus striatus C. L. Koch 0/2 0/9 R 88 Zulka et al. Appendix: (Continued)

Number Species Site Statusa

Ungrazed Grazed m/f m/f b

75 Tibellus maritimus (Menge) 3/1 Thomisidae 76 Ozyptila simplex (O. P. -Cambridge) 125/9 473/88 77 Ozyptila trux (Blackwall) 1/0 78 Xysticus cristatus (Clerck) 10/1 78 Xysticus kochi Thorell 16/2 80 Xysticus ninnii Thorell 4/0 F Salticidae 81 Euophrys frontalis (Walckenaer) 0/1 82 Euophrys petrensis C. L. Koch 1/0 83 Myrmarachne formicaria (De Geer) 1/0 84 Sitticus sp. 4/2 85 Talavera aequipes (O. P.-Cambridge) 1/0

Total 977/588 2335/842 aR = rare species in Central Europe; H = halophilic species; F = record of faunal interest; P = pioneer species. bm = male; f = female. Comments 24 Agreeing with the description of Wunderlich (1992). 41 The second Central European record of this species, described by Hippa and Mannila (1982) from Finland. 71 Identi®cation con®rmed by E. Bauchhenss (in litt.) 84 nov. sp. (Logunov and Kronestedt, in prep.)