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 |
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