How to take part

• Top 10 tips
• Your questions answered

Your questions answered

Does time of day matter?

The time of day you do your birdwatch may affect the numbers and variety of birds you see. Generally birds are more active earlier in the day, searching for food after the winter night.  

However, differences you may see in your own garden throughout the day do not affect the overall results thanks to the large number of gardens involved.  

As with other variable factors such as weather conditions and availability of food, their effects are evened out because our analysis uses information from thousands of different gardens. 

How do I submit my results?

The online form will be open from 24 January 2009 for you to enter your counts.

How does the RSPB use the results?

The aim of the Big Garden Birdwatch is to count garden birds in a consistent way so we can compare bird populations, year after year. Once all the forms have been sent in, we can build up a picture of bird numbers and which regions different species are seen in. 

We are not attempting to count all individual birds in the UK (an impossible task) but to count a proportion of their population in the same way every year.

Weather makes such a difference to the results. Why don't you record it on the form?

Over the 25 years of data collection, we have experienced a wide range of weather conditions. Since weather can vary between days and different parts of the UK over the birdwatch weekend, its effect on the birds we record is a random factor. 

If we were recording the changes in bird numbers between years, there would be some value in collecting this information. However, we record trends over many years so factors like weather do not alter these long-term trends.

What can the Big Garden Birdwatch tell us?

The main advantage Big Garden Birdwatch has over other surveys is its massive geographical coverage thanks to the huge number of gardens watched around the UK. 

The individual changes a participant may notice from one garden would not give a true representation of what is actually happening on a broader scale, but because results are only ever presented using combined information from thousands of gardens we are able to get the bigger picture. 

The results can be broken down and analysed at a country, region or county level, providing a huge sample of gardens from which we can draw trends. In addition, mapping the results for a particular species in any one year gives us a detailed picture of a species distribution and abundance.

When I carried out my Big Garden Birdwatch, I didn't see many birds. How can the results be accurate?

The huge number of people who take part in the Big Garden Birdwatch means that overall results will be accurate. Some people will see fewer birds than average during their hour's birdwatch, whilst others may see more – but these will balance each other out, giving a good overall picture of garden bird numbers in the UK Our results are in line with the results of more complex monitoring surveys.

Why is the Big Garden Birdwatch in winter?