Adder Numbers

Yea r

Sites Surveyed

Sites with Adders

Matur e Males

Mature Females

Total

Average per Site

1990 56

50

185

55

240

4.8
1991 76

61

211 56

267

4.4
1992 78

55

159 33

192

3.5
1993 80

59

186 70

256

4.3
1994 76

50

153

29

182

3.6
1995 76

44

103 14

117

2.6
1996 80

41

112 32

144

3.5
1997 84

44

102 31

133

3
1998 85

42

103 34

137

3.3
1999 67

35

100 20

120

3.4
2000 87

24

69 13

82

3.4
2001 20*

18

54

9

63

3.8
2002

20**

13

36 17

53

4
2003

20**

9

26 10

36

4
2004 20

11

30 10

40

3.6

* Limited by FMD restrictions

   **Surveys restricted to selected sites

 
Return to Article