Severe weather protocols
Birds are likely to become more energetically stressed in cold conditions, when the costs of maintaining body temperatures are increased and food may become harder to find. Impacts may be particularly significant for water birds, including ducks, geese and waders, which tend to feed in exposed habitats and may be unable to access mud or water to find their food when temperatures drop below freezing (Clark 2004, Davidson & Evans 1982, Mitchell et al. 2000).
The Severe Weather Scheme
Disturbance caused by human activity could exacerbate the situation and, in recognition, the Joint Nature Conservation Committee (JNCC) funds a Severe Weather Scheme during the wildfowl shooting season, which runs from 7 November to 20 February. Under the Wildlife and Countryside Act Section 2, the relevant Secretary of State(s) has power to impose a temporary suspension of waterfowl (ducks, geese and wader) shooting during prolonged periods of cold weather. The thresholds used to define such periods are based on daily temperature data gathered from 25 meteorological stations located throughout Britain, and have been agreed by the relevant nature conservation bodies, government departments and non-governmental organisations, including BASC, RSPB and WWT.
Response to Severe Weather Alerts in Britain
When more than half of the 25 meteorological stations in any individual country (Scotland, England or Wales) have recorded frozen conditions for seven consecutive days, an alert is sent by JNCC to a number of organisations, including BASC, WWT, RSPB and BTO. Receipt of this alert may prompt BASC to issue a national call for voluntary restraint from shooting; after 14 days, a national statutory suspension of wildfowl shooting is imposed (for more details see here). If frozen conditions are recorded in more than 12 of the 25 stations, regardless of the country in which they are located, equivalent suspensions are considered/implemented across all three countries simultaneously. Given that ringing activities also have the potential to cause temporary disturbance, suspensions of catching activities targeting water birds mirror those applied to shooting of wildfowl. Once confirmation of wildfowling suspensions has been received from the relevant Statutory Nature Conservation Body (SNCB), BTO contact all ringers to alert them of the situation.
Any statutory suspension is in place for an initial period of 14 days. The situation is reconsidered by DEFRA and the SNCBs after seven days and, if conditions have improved and are forecast to continue to do so, the suspension may be truncated at this point; if there has been no thaw and the weather remains severe then the statutory suspension continues for the full 14 days. If severe weather conditions look to continue beyond the 14 day period then there can be an extension of the suspension of activities via a second statutory agreement, which is managed in the same way.
Response to Severe Weather Alerts in Ireland
We are in consultation with relevant organisations in Northern Ireland and the Republic of Ireland with regard to their protocols on severe weather monitoring and will update this webpage accordingly when protocols are finalised.
Response to severe weather conditions in other situations
To date, conditions that meet Severe Weather thresholds relating to statutory suspension have not been recorded outside the wildfowl shooting season. A key element of the extensive training undertaken by all ringers before they are able to operate independently involves the ability to make appropriate decisions concerning operations during inclement weather however and Ringing Scheme guidance stresses that full consideration of conditions is both essential and expected, regardless of the species and capture technique involved.
Clark, J.A., Baillie, S.R., Clark, N.A. and Langston, R.H.W. (1993) Estuary Wader Capacity Following Severe Weather Mortality. BTO Research Report 103, Thetford.
Davidson, N.C. and Evans, P.R. (1982) Mortality of Redshanks and Oystercatchers from starvation during severe weather. Bird Study, 29, 183–188.
Mitchell, P.I., Scott, I. and Evans, P.R. (2000) Vulnerability to severe weather and regulation of body mass of Icelandic and British Redshank Tringa totanus. Journal of Avian Biology 31, 511–521.
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