The Significance of the Lake Neusiedl Area of Austria for Migrating Geese
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The significance of the Lake Neusiedl area of Austria for migrating geese GERALD DICK Introduction Very little of the special pannonic pasture, Hutweide, remains but fields of winter sown Lake Neusiedl, together with the Seewinkel ccreals and maize provide feeding grounds area immediately to its east, has been for geese. For more detailed descriptions of designated under the Ramsar Convention the area see Festetics and Leisler (1968) and on Wetlands of International Importance Löffler (1979). Especially as Waterfowl Habitat, of which Although mainly important as a staging Austria became a Party in 1982. Located at post for migrating geese, the Lake reedbeds 47°48N 16°49E, about 50 km south-east of also hold 300-400 pairs of Greylag Geese Vienna, the Lake covers some 14,300 ha of Anser anser rubrirostris, the only breeding open water, about 1,300 of which are in goose of Austria. The migrant geese, Hungary (Figure 1). The water is shallow, besides Greylag, are mainly Bean Geese around 1 m, alkaline and strongly fluctu Anser fabalis rossicus and Russian White- ating. The margins have reedbeds, Phrag fronted Goose Anser albifrons albifrons. mites australis, which in places extend 6 km Rare visitors are the Lesser White-fronted into the Lake. In the Seewinkel there are G oose Anser erythropus and the Red about 50 small salty lakes, the largest being breasted Goose Branta ruficollis. Some Lange Lacke of 150 ha, which was until published data on goose numbers are avail recently a World Wildlife Fund reserve. able from earlier years, namely those of Figure 1. Geographical situation of Austria (A): The Danube in Lower Austria is symbolised by the small arrow. In = Lake Neusiedl, east of it Seewinkel area, Lange Lacke; 1 = Friuli-Venezia Giulia and East Veneto (I); 2 = Lac de l’lchkeul (TUN); 3 = El Kala wetlands (ALG); 4 = Kopacki Rit (YU); 5 = Burgas (BG); 6 = Evros Delta (GR, TR). 19 W ild fo w l 38 (1987): 19-27 20 Gerald Dick Bauer and Glutz (1968), Leisler (1969), between Bean Geese, which went up to Lebret (1982) and Van den Bergh and 40,000, while Whitefronts reached almost Philippona (1985). 10,000 only once. Greylag were only The main objective of the present study counted very intermittently, but their was to determine the phenology of the presence in this period is proved. goose migration. The monthly counts of the subsequent four years are shown in Figure 2. The first species to arrive in autumn in Seewinkel is M eth ods the Greylag in September (e.g. 8.9.84: 127 birds; 24.9.86: 119 birds). Neckbanding of Data for the seasons 1980-81 to 1982-83 individuals has shown that they originate were gathered non-systematically by from Czechoslovakia as well as from several observers. Since the season 1983-84 Austria. The Austrian geese return to monthly counts were carried out simul Seewinkel after a summer movement to taneously in Austria and Hungary. The Southern Moravia (Dick et al. 1984). Occa counts were made in the morning during the sionally some Bean Geese can be observed departure of the geese from their night at the end of September (18.9.84: 2; roosts. Usually four teams counted at the 24.9.86: 23), but the bigger flocks do not main roost, Lange Lacke. Depending on arrive until October (e.g. 21.10.81: 1,000; the actual distribution of geese one to four 8.10.85: 1,600). At this time the Greylag is teams counted on the eastern shore of Lake already present in bigger numbers (e.g. Neusiedl as well as on the other larger 8.10.83: 10,000; 6.10.84: 1,800). The Lacken. Supplementary data originating Whitefront is normally the last species to from observations during the day were arrive (e.g. 13.10.85:2; 17.11.85:146). This added where appropriate. The date of the general pattern of arrival applies to the count was determined by the International whole period of observations, although Waterfowl Research Bureau as the Sunday there are some exceptions (see Figure 2). closest to the 15th of the month. Additional The maximum number of Bean Geese data from other countries are available recorded during the monthly counts from Czechoslovakia, Italy, Yugoslavia and amounts to 21,000 individuals (November T unisia. 1985). The maximum number of White- front was 6,400 (February 1984) and of R esu lts Greylag 9,000 (November 1984). C ount data Environmental conditions For the seasons 1980-81 to 1982-83 there Autumn migration is slower than spring are only few data available (Table 1), but migration, and large flocks of geese can there is an obvious difference in numbers remain in the area under favourable Table 1. Aperiodic counts from the Seewinkel, 1980-81 to 1982—83. Date A. fabalis A. albifrons O ther Source 26.10.80 23750 0 4000 A. anser Lebret 1982 12-13.11.80 22000 3000 Lebret 1982 18.1.81 11 10 A. Grüll End 2.81 19000 V. d. Bergh & Philippona 1985 7.3.81 16-18000 3500 2500 A . anser Lebret 1982 15.3.81 5930 1000 A. Grüll 15.11.81 18950 3000 A. Grüll 17.1.82 1078 400 440 indet. A. Grüll End 2.82 11000 V. d. Bergh & Philippona 1985 14.3.82 1448 75 A . Grüll 14.11.82 ca 21844 ca 7275 A. Grüll 16.1.83 17445 at least 9555 8910 indet. A. Grüll End 2.83 40000 V. d. Bergh & Philippona 1985 13.3.83 613 205 882 indet. A. Grüll Migrating geese on Lake Neusiedl 21 Figure 2. Monthly goose counts: 1983-84 to 1986-87 in Seewinkel. Number of geese in thousands, rounded to the nearest hundred. Unidentified geese = indet.; * = approximately; < = less than 100. 22 Gerald Dick Figure 3. Relation between temperature and goose numbers. Monthly means of temperature (weather station Frauenkirchen): circles and broken lines. Total of geese in Seewinkel (rounded to the nearest thousand) in the years 1983-84 to 86-87: squares and solid lines. 5 4 3 cr co L U LU CÛ LU 2 2 O 1 0 83^ 84 8 4 /8 5 85/86 86^ 87 weather conditions. Using the monthly geese w ere counted (T able 1, Figure 4). T he mean of temperature to assess weather unfavourable coincidence of low tempera conditions, it can be clearly shown that ture and deep snow in 1986-87 correlates more geese remain under mild circum with a complete disappearance of geese in stances (Figure 3): e.g. in the season 1983- January. 84, 44,000 geese were counted in January Spring migration to the breeding areas after the weather since 16th December had generally occurs faster (Elkins 1983) and turned warmer, accompanied by rainfall this also applies to Seewinkel. Unfavour (maximum temperature 2.1.84: 10.5°C). able weather conditions at this time do not The following winters were rather severe: dramatically alter the count totals. The in January 1985 only 80 geese were counted, main migration of Bean and White-fronted in January 1986 1,450, and during the Geese in spring 1987 occurred before the extremely cold January 1987 (minimum official count day in March and approxi temperature 13.1.87 — 19.5°C), no geese at mately 25,000 were present on frozen and all were present. snow covered Lange Lacke on 4th March Apart from the temperature the duration (Figure 2), with a temperature of — 11°C. of snow cover in late autumn and between This is extremely interesting as this March December and January also seems to be an was the coldest since 1958 (minimum tem important factor in determining whether perature — 18°C on 5th March), with heavy geese leave the area. Deep snow obviously snowfall and blizzards reported even from affects the availability of winter cereals. An the middle of Greece and Yugoslavia. Also unusually high number of geese occurred in in February 1986 there were 3,000 uniden January 1984, a year where from October to tified geese and 370 Greylags on Lange the end of January no snow had fallen Lacke (25th February frozen and snow (Figure 4). Similar conditions were covered, — 13°C). The same phenomenon recorded in 1982-83 (January mean tem occurred in February 1983 (Table 1; mini perature: 4.3°C), when more than 35,000 mum temperature: 23rd February — 12°C). Migrating geese on Lake Neusiedl 23 Importance o f other areas for geese resent a valuable supplement (Figure 5). This shows the importance of the whole Seewinkel is the only important place for area for the geese. The Bean Goose also geese in Austria, although there are a few dominates in the Hungarian counts. In observations from the Danube Valley in October this species is more frequent there Lower Austria (Figure 1) since 1970-71 (F. than the others, whereas the Greylag can be Böck; FI.P. Kollar; R. Parz; A. Ranner, in the more numerous in Austria. In general litt.). During the cold winters 1984-85 the relationship betw een the various species (December to January more than 1,000) is similar to that in Austria, with a spectacu and 1986-87 (January at least 100), quite a lar exception in January 1987. Then ice and lot of Bean Geese were reported from snow resulted in the absence of geese in Styria (Figure 1 ; Hable 1986; Sackl, in litt.). Austria, but there were 530 in Hungary. L ake N eusiedl is divided into tw o parts by When the Austrian and Hungarian data are the Hungarian border in the south.