Big Garden Birdwatch: spend an hour with the birds this weekend European visitors It's not all bad news. Sightings of coal tits, long-tailed tits and blackbirds are increasing. And there's a new bird on the block - the blackcap. Usually a summer resident which nests in large gardens but migrates to Iberia in autumn, the blackcap has recently been turning up at British bird feeders in winter. Only, they're not the same blackcaps we see in summer; these birds have travelled here from Europe. Like "British" blackcaps, they also mostly head to Iberia, but a splinter group has started to come to Britain instead, where they feast on the peanuts and fat balls in our feeders. There are many advantages of spending winter in Britain over Iberia: the birds have a guaranteed source of food and a comparatively short return journey to their spring breeding grounds. Because they arrive home sooner than the Iberian set, they have the pick of the best nesting sites, and are also probably in much better physical condition to breed. The success of these new winter migrants means more and more of them are coming over and turning up at our bird feeders. Surely it's only a matter of time before they enter the top 20 of the BGBW. So how do you spot a blackcap at your bird table? Roughly green-grey in colour, the male has a black "cap" and the female has a chestnut-coloured one. They're also quite aggressive, so are hard to miss. The RSPB's Richard Bashford explains that, like robins, blackcaps "establish garden territories in winter, so they are likely to be aggressive towards other birds at feeding stations because they consider them to be their own." The big count What if there are no birds to count? Like many gardens in Britain, it took a long time for any birds to show up in mine this winter. Such has been the concern among bird lovers that the RSPB had to put out a press release to explain what was going on. The answer was simple: the mild weather meant birds could find food in the wild - they didn't need us. "Birds tend to be pushed into gardens the harder the weather is," says Bashford, "so the milder the weather, the fewer birds you will see in your garden." This doesn't bode well for the Big Garden Birdwatch, as finches and winter migrants such as redwings and fieldfares are less likely to turn up. However, it's still worth taking part. "Even if the weather is mild and there are fewer birds in your garden on the day of the count, please do still submit your results," urges Bashford. These low sightings can still be compared to those of other mild winters, helping track national population trends. What to feed birds Regardless of the weather, birds will soon be entering nesting season and need to be in good condition to breed. Give them nutrient-rich sunflower and niger seed, peanuts, halved apples, mealworms, suet products and grated cheese. Continue to feed them after they have started nesting, as while they gather natural food for their young they will still need to feed themselves. Hulled sunflower hearts will save them time and energy, as they won't have to remove the husk. Last year many garden birds failed to raise young successfully. Owing to the cold, wet spring, there were fewer insects to forage. If conditions turn bad, leave a dish of live mealworms for birds, which they may choose to feed to their young as an alternative. Avoid leaving out whole peanuts, which birds may feed to their young if natural sources of food are hard to find. These can choke chicks. Only put peanuts out if you have a fine mesh feeder, or are prepared to grind them into smaller, more manageable pieces. Don't forget ground-feeding birds such as blackbirds, robins and thrushes. Halved apples and mealworms are ideal for them. Keep bird baths topped up. Birds drink from bird baths but also use the water to preen their feathers - helping them to insulate their bodies more efficiently and fly faster, potentially making them better able to fly from predators as well as travel to and from the nest more quickly. Read more: How to help our most threatened garden birds