Bestandslücken
[N=21.67; 22.1968,18,20; 23.1969,16,18; 24.1971,2/3,9/10,17,20/25,27/29,35/38,40; 25.1972,27/28,49; 27.1973; 28.1974,1/8,10/20,22-27,32/33,36,38/39,41,44,47,49/50; 29.1975,9/10,16/17,20/21,25/26,34/35,39/40,42,47,49/51; 30,1976,1/4,6,8/18,20/49,51/52; 31.1977.1/11,14,16/49,51/52; 32.1978,1/10,13/19,21/32; 33.1979,26,31; 34.1980,25/26; 35.1981,27/28,36/44,46/51; 36.1982; 37.1983; 38.1984,1/26,50/25; 39.1985,1/3,41; 40.1986,31,46; 41.1987,19,50/51; 43.1989,31,43,45/50]