Use the key written below the biologist`s notebook to help him find the name of the birds in his book.
1 Straight beak: Go to 2
Curved beak: Go to 3
2 Crest of feathers on head: It is a lapwing
No crest of feathers on head: It is an oystercatcher
3 Beak curved downwards: It is a curlew
Beak curved upwards: It is an avocet.