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Home > WeBS Alerts Contents > SSSI Contents > Site Accounts
Trends have been assessed over the short-, medium-, and long-terms (5, 10 and up to 25 years respectively). Where data have been collected for less than 25 years (see Methods) the maximum number of years available are used for calculating long-term alerts (specific details are available within the detailed account). Where time periods for which Alerts are triggered are given in parentheses this indicates that the degree of change in numbers that has triggered that Alerts might be considered within the range of normal fluctuation for a "healthy population" of the species in question over the period indicated (see Methods 2.3 - biological filter), and as such will not necessarily be discussed in detail.
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