In April, Listen and Look Out for …

Chiffchaffs and Willow Warblers

By the last week of March, the reserve was alive with the distinctive song of the chiffchaff. In April, it will be joined by its close relative, the willow warbler. How can you tell them apart? Probably not by looking at them. Even experienced birdwatchers struggle to tell the difference. However, if you hear them, you can’t go wrong: their songs are completely different. The chiffchaff, rather monotonously, sings its name, whereas the willow warbler’s song is a more complex, sad-sounding sequence of descending notes. In recent years, willow warblers have become less common in Southern Britain, probably due to climate change.

Comma butterflies

These can be seen at almost any time of the year, but become common in Spring, when you can see them basking in sunny spots. They are easy to identify as their wings have a distinctive “ragged” appearance. To see how they got their name you need to find one with its wings folded and, if you look closely, you will see a white comma-shaped mark on its underwing. The comma is a success story among British butterflies as numbers have increased greatly in the last fifty years. In contrast to the willow warbler, it has benefited from the warming climate.

Bumble Bees

You might have spotted large, queen bumblebees in March, looking for suitable sites in which to build their nests. In April you will probably also notice some smaller, worker bees, as well as a greater range of species. There are 24 species of bumble bee in the UK, about eight of which are very common, and they can be hard to tell apart. The photograph shows one of the easiest to identify, the red-tailed bumble bee (Bombus lapidarius).

Nightingales

Finally, Paxton Pits is famous for its nightingales and they usually arrive in the first half of April. No British bird comes close to matching them for the beauty and complexity of their song so once you have heard it you will never forget the experience. Sadly, numbers have fallen on the reserve in the last few years, but you might still be lucky enough to hear them and the rangers and volunteers are working hard to provide suitable habitat for them.