[alanjns]

1. In bird/animal eggs, the chalaza is composed of one or two spiral bands of tissue that suspend the yolk in the center of the white. It does not act like an umbilical cord; the growing embryo receives its nutrients from the yolk. The purpose of the chalaza is to hold the yolk in place.

2. The Hawfinch is the UK's largest finch

3. The answer is a ''Fulmar''. In the Icelandic language, ''Fulmar'' translates as ''Foul Gull''. It is so called because of a foul smelling oil that it produces and stores in it's stomach and uses as a defence mechanism - if a predator gets too close they have the ability to 'spit' the oil in their direction. The oil can matt the feathers of predators and potentially drown them.

4. The Shelduck has a migration moult of over 100,000 birds in the Waddensee.

5. 'Migratory restlessness' is also known by the German word, 'Zugunruhe'. It is the in-built desire to build up energy and fat and to migrate.

6. The Bar-tailed Godwit makes a non-stop migratory flight of approximately 7,250 miles.

7. The bird in the attachment is a female Merlin.

8. Birds that fly in a 'V' formation, do so because of the slip stream effect. The wing beats of the birds in front create up-drafts that the bird behind can use to creat lift and make flying easier. The flock takes it in turns to be leader.

9. The aerial display of Starlings is called a murmuration. Some people suggested 'Black sun' - after an internet search, I found that this is a term localised to the Netherlands region - I checked with the good people at Fat Birder who agreed with murmuration.

10. Great Britain does not have a national bird - the Robin is the national bird of the UK - you all spotted that. Scotland has the Golden Eagle and Wales the Red Kite. No one could prove the existence of a Republic of Ireland national bird.