BRUSSELS- Minutes after plunging two metres (6.5 ft) to the ground as his mother gave birth, baby giraffe Twiga was frolicking round his pen as the newest arrival at Belgium's Planckendael Zoo.

"They fall down two metres because mother giraffes don't lie down," said zookeeper Sil Waumans.

"It is always a scary moment to see whether they walk afterwards, but after 20 minutes he was already on his legs."

Twiga, already two metres high, is named after the Giraffe Conservation Foundation's Twiga Tracker initiative, which follows giraffes' movements across Africa using satellite tags. Twiga is Swahili for giraffe.

The conservation charity estimates the number of giraffes in the wild has fallen more than 40 percent in the last three decades to just 100,000.

"It is a lively little one, he has already hopped and galloped around so it is very nice to see," Waumans said of Twiga, who can be seen with his mother Barbie and five other family members at Planckendael, 20 km (12 miles) north of Brussels.

(Reporting by Megan Dollar Editing by Robin Pomeroy) ((Megan.Dollar@thomsonreuters.com;))