It's very early in the morning and I'm sitting outside. It's also very cold and dark. With me is Jim Nightingale, and he is the reason I'm up so early. He passes me a hot cup of coffee. "Not long to wait now," he says. I hope he's right. After a few minutes there is a very weak light in the east, and then I hear a bird singing. It sings very loud and very clear. "That's the robin ," says Jim. A few more birds start singing with the robin and Jim knows the names of them too. Half an hour later, there are more and more birds singing, and it's very loud! Suddenly, all around us the air is full of the sound of birdsong. This is the dawn chorus , and it's beautiful. "Wow, this is amazing!" I tell Jim, who is smiling. "Is there a dawn chorus every morning?" "Birds can sing any time of the year but the best time is the end of winter and during the spring. This is when the birds sing most." "Really? So, why do they sing?" I ask. "Well, there are two reasons," explains Jim. "Most of the songbirds who sing are males. They want to find a female so they sing to show how strong they are. The females listen and choose the best singer! The birds also sing to tell other males to go away. They need their own area; they don't like sharing with another male." I listen to the birds; the songs seem too much to me. "Do the birds sing a special song in the morning?" "That's a good question," replied Jim. "The successful birds have many kinds of calls and songs. Sometimes they copy the songs of other birds. This makes it sound like there are many birds in that place already and other males stay away. Also the female likes songs with different notes. Some birds, for example the European wren, have songs that contain over 700 different notes per minute!" So, how does Jim know so much about birds? Well, he works as a volunteer for the Royal Society for the Protection of Birds. He is trying to help the birds live in the modern world. "More and more of the birds' habitat disappears every year. The sparrow, for example, was a very common bird in the UK, now it's in danger." By now the sun is up and the birds are quiet. It's light so they can start looking for food, they need a big breakfast after all that singing. The text is mainly about  _  .
the robin's songs the birds' habitat why birds sing how to protect birds