The table shows the number of people who participated in wildlife observation in Britain between 2001 and 2009, divided into adults and children.
Overall, participation increased over the period for both groups. Adults generally outnumbered children, except in 2009 when the figures were equal.
In 2001, around 36 thousand adults took part, compared with 48 thousand children. By 2003, adult participation rose sharply to 212 thousand, while the number of children fell to 36 thousand, giving a total of 248 thousand participants.
In 2005, the number of adults reached a peak of 332 thousand, whereas children declined slightly to 32 thousand. Both figures then decreased marginally in 2007, to 331 thousand and 31 thousand respectively. In the final year, participation levels for adults and children were equal at 270 thousand each, resulting in a total of 540 thousand.