0:00:02 > 0:00:06The robin. Britain's national bird.
0:00:06 > 0:00:09Inquisitive, bright-eyed...
0:00:09 > 0:00:11and naturally tame.
0:00:11 > 0:00:16Our quintessential garden treasure and beloved Christmas icon.
0:00:18 > 0:00:21Behind the romantic image though,
0:00:21 > 0:00:25winters for small birds are often far from festive.
0:00:26 > 0:00:31Even fiery red feathers can't save them from the iciest of nights.
0:00:35 > 0:00:39A few fly south, but most stay home for Christmas,
0:00:39 > 0:00:42despite risking their life in the cold.
0:00:44 > 0:00:47Imagine if there was an English country garden
0:00:47 > 0:00:51where it was warm all year round.
0:00:54 > 0:00:59Well, for a lucky few, the fantasy has come true.
0:00:59 > 0:01:04They found an unexpected robin heaven in the garden of Eden.
0:01:27 > 0:01:30The Eden Project, architectural marvel.
0:01:30 > 0:01:33A botanical space port in a Cornish quarry.
0:01:46 > 0:01:49Thanks to its futuristic biomes,
0:01:49 > 0:01:52it's many worlds in one.
0:01:54 > 0:01:59Home to a fabulous collection of plants,
0:01:59 > 0:02:04a floral extravaganza from all around the world.
0:02:15 > 0:02:18This was all designed and planned.
0:02:18 > 0:02:23A place for humans and plants to grow and flow together.
0:02:36 > 0:02:39But who could have guessed that this Eden
0:02:39 > 0:02:43would be gatecrashed in quite such a charming way?
0:02:45 > 0:02:51Bright-eyed interlopers with a touch of Mary Poppins.
0:02:58 > 0:03:02Christmas time is a busy time for both humans and the small birds.
0:03:06 > 0:03:09They seem so happy and sing so loudly that some visitors think
0:03:09 > 0:03:13there's piped birdsong being played.
0:03:13 > 0:03:16But it's the robins proclaiming to each other
0:03:16 > 0:03:19that they are now ready to breed.
0:03:21 > 0:03:25After all, Christmas is the season to be merry,
0:03:25 > 0:03:29a chance to celebrate together. And for robins,
0:03:29 > 0:03:34it's the time to flirt, find a mate and set up home together.
0:03:36 > 0:03:42If they need a break, Eden's humans lay on entertainment for them.
0:04:06 > 0:04:13Not many other robins get to star in their own, real-life Christmas card.
0:04:41 > 0:04:44As winter slides into spring...
0:04:44 > 0:04:47Eden is transformed.
0:04:53 > 0:04:58There are riots of colour, both inside and out.
0:05:14 > 0:05:21Lots more people arrive just when the robins are looking for some privacy.
0:05:25 > 0:05:28Male and female robins look identical.
0:05:28 > 0:05:32Only by watching their behaviour can you tell the sexes apart.
0:05:34 > 0:05:38If you see a robin making a nest, then you know she's a she.
0:05:38 > 0:05:41Only hens are homemakers.
0:05:43 > 0:05:47It's only the females who are courted by being fed, too.
0:05:48 > 0:05:52One of the reasons robins are so endearing
0:05:52 > 0:05:55is that couples set up home in the unlikeliest of places.
0:05:59 > 0:06:04One pair have settled in part of a daffodil display.
0:06:11 > 0:06:16Robins waste no time when it comes to breeding.
0:06:16 > 0:06:19Their eggs hatch in around two weeks
0:06:19 > 0:06:23and the young leave the nest about a fortnight later.
0:06:27 > 0:06:32Soon, fluffy fledgings teeter about amongst the agaves.
0:06:32 > 0:06:35A surprising scene in a plant from Mexico.
0:06:44 > 0:06:47By high summer, the borders and bedding schemes of Eden
0:06:47 > 0:06:49are truly heavenly.
0:06:54 > 0:06:58The paths soon turn into rivers of people.
0:07:08 > 0:07:12But while it might be a delight for humans,
0:07:12 > 0:07:14how do the crowds affect the robins?
0:07:19 > 0:07:23Happily, British robins are the friendliest in the world.
0:07:28 > 0:07:31You might be surprised to learn that, in Europe,
0:07:31 > 0:07:35robins are shy, retiring and rare by comparison.
0:07:35 > 0:07:40It's only in Britain that they have lost their fear of man.
0:07:40 > 0:07:45Even our name robin is a pet name from the mists of our folklore.
0:07:48 > 0:07:51There are around 10 million alive today,
0:07:51 > 0:07:54far more than there were thousands of years ago.
0:07:54 > 0:07:58It was our national love of gardening that helped them.
0:08:01 > 0:08:05Robins need dense, low vegetation in which to live and breed.
0:08:05 > 0:08:08Gardeners like a bit of privacy too,
0:08:08 > 0:08:12so they often plant dense hedges and borders.
0:08:14 > 0:08:19We Brits even feed hungry birds in winter, too.
0:08:20 > 0:08:25The different garden spaces of the Eden Project
0:08:25 > 0:08:28along with the human visitors and their picnic scraps do the same,
0:08:28 > 0:08:31except on a very grand scale.
0:08:32 > 0:08:37This futuristic oasis has everything robins need to thrive.
0:08:37 > 0:08:42No wonder the gardens of Eden were so cheekily invaded.