1. Non-breeding culmen is straight, appears slightly uptilted. 2. Among standard measurements, the exposed culmen is. 3. They have a short conical black bill with an obvious curve to the culmen . 4. The culmen was arched, and the maxilla overlapped the mandible at the base. 5. It is distinguished, however, by a larger bill with a straight culmen . 6. The culmen length measures 194 275mm. 7. Juvenile specimens can be determined by observing small corrugations on the lateral areas of the beak culmen . 8. The shape or color of the culmen can also help with the identification of birds in the field. 9. After the autumn culmen , but in spring the bill becomes bluish-grey with a small black tip. 10. Pine siskin in its typical culmen , compare with a short bill in European siskin, with a decurved culmen.
