What Is the Big Garden Birdwatch?

The Big Garden Birdwatch is an annual citizen science event organised by the Royal Society for the Protection of Birds (RSPB), one of the UK’s oldest and most respected wildlife conservation charities. Founded in 1889, the RSPB manages over 200 nature reserves across England, Scotland, Wales, and Northern Ireland, and its Big Garden Birdwatch project has grown from a modest school holiday activity into a national institution.

In 2023, over 700,000 people took part, collectively counting more than 9 million birds. That level of participation makes it scientifically significant — not just a pleasant hobby. The data gathered helps ornithologists, conservationists, and government bodies including Natural England, NatureScot, and Natural Resources Wales to understand how garden bird populations are changing year on year.

The premise is beautifully simple: you watch your garden, balcony, local park, or any outdoor space for exactly one hour, and you record the highest number of each bird species you see at any one time during that hour. That is the entirety of the task. No specialist equipment is needed, no formal qualifications, and no prior experience of birdwatching is required.

The survey has revealed some genuinely striking trends over its forty-plus year history. House sparrow numbers counted in UK gardens have fallen by more than 57 per cent since the first Birdwatch. Starlings, once so abundant that murmurations over Brighton Pier were a guaranteed winter spectacle, have declined dramatically. Meanwhile, corvids like jackdaws and magpies have become far more frequent garden visitors than they were in the 1980s. These shifts tell a story about the changing British countryside, the intensification of agriculture, urban development, and the loss of insect life that these birds depend upon.

When Does It Take Place?

The Big Garden Birdwatch takes place across one weekend at the end of January each year. The RSPB typically announces the precise dates in the autumn. In recent years, the survey has been held on the last full weekend of January — for example, 25–27 January 2025.

January is chosen deliberately. By late January, the Christmas berry crops have largely been stripped from holly and hawthorn hedges, natural food sources in the countryside are at their scarcest, and birds are under real pressure to find enough to eat. This means garden feeding stations are especially busy, and many species that spend spring and summer in farmland or woodland will venture closer to houses. It is also the period when Scandinavian visitors — redwings, fieldfares, and the occasional waxwing turning up in supermarket car parks from Aberdeen to Norwich — are most likely to be seen.

You can carry out your one-hour count at any point during the three-day survey window. A quiet Saturday morning in your pyjamas, peering through the kitchen window at a dunnock on the patio, counts just as much as a dedicated session set up with binoculars and a notebook.

The RSPB advises checking their website at rspb.org.uk/birdwatch in the autumn preceding the survey for the confirmed dates of the next event.

How to Register for the Big Garden Birdwatch

Registration is free and straightforward. You do not need to be an RSPB member to take part, though many participants choose to join the charity after getting involved.

Registering Online

The quickest way to register is through the RSPB website. Visit rspb.org.uk/birdwatch and click the registration link, which typically goes live in October or November. You will be asked for your name, email address, and postcode. Your postcode is important — it allows the RSPB to map results geographically, comparing urban gardens in Manchester with rural settings in Herefordshire or coastal locations in Pembrokeshire.

Once registered, you will receive a confirmation email with a link to your personalised results submission form. The RSPB will also send you their free Birdwatch pack, which historically included a species identification chart and a recording sheet, though in recent years the organisation has moved towards encouraging digital-only packs to reduce waste.

Registering by Post or Phone

If you prefer not to register online, you can telephone the RSPB on their membership and enquiries line. The charity also accepts registrations by post if you write to their headquarters at The Lodge, Potton Road, Sandy, Bedfordshire. This is especially useful for older participants who may not be comfortable with online forms.

Registering as a Group or School

Schools, wildlife clubs, care homes, and community groups across the UK regularly take part as organised groups. The RSPB provides specific resources for schools, tied to the Key Stage 2 science curriculum, which makes the Birdwatch a wonderful outdoor learning activity. A class of Year 4 pupils in a Derbyshire village school recording sparrows and blue tits in their school grounds is generating data that is every bit as valid as that submitted by a retired birdwatcher with forty years of experience.

How to Count the Birds: The Method Explained

The counting method used in the Big Garden Birdwatch is designed to be consistent and comparable across all participants, which is what gives the data its scientific value.

The One-Hour Rule

You watch your chosen spot for exactly one hour. You do not need to stand outside in the cold — you can watch from indoors through a window, which is actually what most people do in late January in a Northumberland garden. You can move around your house to get a better view of different areas, but you must be watching a single defined space.

Record the Maximum Number at Any One Time

This is the key rule that catches out many first-time participants. You do not count every bird you see throughout the hour and add them all up. Instead, you record the highest number of each species you see at any single moment during your hour.

Here is a practical example: imagine you are watching a garden in suburban Leicester. During your hour, you see five blue tits visit your peanut feeder at various points. But the maximum number present in your garden simultaneously at any one moment was three — perhaps two on the feeder and one waiting on the fence. You would record three blue tits, not five.

This approach is used because birds move in and out of gardens constantly. If you counted every individual visit, the same robin could be counted twenty times in an hour. By recording the peak simultaneous count, the RSPB gets a more accurate and comparable snapshot of how many birds are actually using each garden at a given time.

What Counts as Your ‘Garden’?

Your survey area can be any outdoor space you have access to: a traditional back garden, a front garden, an allotment, a communal green space, a school playground, a balcony, or even just the view from a window over a public park. The important thing is that you define your space at the start of the hour and stick to it.

If you live in a flat with no outdoor space, the RSPB actively encourages you to take part by watching from a window — even a view of the sky, a rooftop, or a tree in the street outside qualifies. A swift spotted from a Bristol flat window is just as valuable to the count as a goldfinch seen in a Somerset orchard.

What Not to Count

Birds seen flying over your garden without landing or pausing do not count unless they are birds that naturally spend their time in flight, such as swifts or swallows. However, in late January, you are very unlikely to encounter those species as they winter in sub-Saharan Africa. Stick to birds that are actively using your space — perching, feeding, bathing, or simply sitting.

What to Look For: Common Garden Birds in January

January is one of the most rewarding months to watch garden birds in the UK. Here is a guide to the species you are most likely to encounter across British gardens during the survey weekend.

Robin (Erithacus rubecula)

Britain’s unofficial national bird, the robin is territorial and tends to visit gardens alone. Its bright red breast makes it one of the easiest birds to identify, and its year-round presence means it is counted in virtually every Big Garden Birdwatch. Robins are typically solitary — if you see two, there is a good chance they are about to have a disagreement over territory.

Blue Tit (Cyanistes caeruleus)

The blue tit is one of the most acrobatic visitors to garden feeding stations, perfectly capable of hanging upside down from a fat ball feeder. In January, they often travel in loose flocks with other tit species, so a sudden influx of blue tits on a cold morning is not uncommon. They are strongly associated with peanut feeders and suet products.

Great Tit (Parus major)

Larger and bolder than the blue tit, the great tit tends to dominate at bird tables. Its distinctive “tea-cher, tea-cher” call is one of the most recognisable sounds of a British winter morning. The great tit’s bold black head stripe and yellow breast make it straightforward to identify.

Moving Forward

Once you have the fundamentals in place, the possibilities open up considerably. The UK offers fantastic opportunities for anyone interested in this hobby, and with the right foundation you will be well placed to make the most of them.