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Beginning Your Survey

Ensure you are in position to begin your survey walk approximately 20 minutes after sunset. Sunset time tables are provided in your pack, but more localised information is available on the internet.

Just prior to starting the survey make the following pre-survey observations and record them on your recording sheet:

1. Start time

2. Temperature (use a thermometer or check next day’s newspaper/web reports).

3. Weather conditions
Weather conditions that may affect bats are recorded including cloud cover, wind speed and rain. Estimate the conditions based on the following options:

• Clear (0 -1/3 of the sky covered with cloud)
• Patchy (1/3 – 2/3)
• Full (3/3)

• Calm
• Light
• Breezy

• Dry
• Showers
• Drizzle

If wind is more than breezy, or rain is more than a shower or drizzle then you should not do the survey.


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