0:00:36 > 0:00:41The Shiant Islands are home to one of the biggest puffin colonies around our coast.
0:00:41 > 0:00:47Every April, thousands of these little squat birds appear from the North Atlantic Ocean
0:00:47 > 0:00:51on an epic journey back to these islands where they were born.
0:00:51 > 0:00:54The puffins have come here to breed, and with a bit of luck,
0:00:54 > 0:00:58most of the eggs will have hatched by now and the proud parents should
0:00:58 > 0:01:01be scurrying in and out of their burrows with food for the chicks.
0:01:01 > 0:01:05That makes it the best time of year for me to get close to these charismatic birds
0:01:05 > 0:01:10and find out just how well they survive on these windswept islands.
0:01:14 > 0:01:18Dumpy, with Day-Glo bills, tangerine feet and tails that look
0:01:18 > 0:01:20as if they've had an encounter with a carving knife,
0:01:20 > 0:01:25puffins are surprisingly agile birds, both in the air and in the sea -
0:01:25 > 0:01:29useful skills when you spend over seven months of the year
0:01:29 > 0:01:32covering thousands of miles of the vast Atlantic!
0:01:34 > 0:01:38The Shiant Islands are a far cry from the puffins' solitary ocean life.
0:01:38 > 0:01:43Here, they've got to get along with the neighbours - 150,000 of them.
0:01:49 > 0:01:51Living so tightly packed together on the island,
0:01:51 > 0:01:55puffins have developed advanced ways of communicating by calling
0:01:55 > 0:01:58to each other, using their bills and different body postures.
0:01:58 > 0:02:03I've just been looking at a group down there. There's one standing up
0:02:03 > 0:02:08very straight and upright. Basically that's saying, "This is my territory and I own this burrow."
0:02:13 > 0:02:16But their posturing is not all about property.
0:02:16 > 0:02:20Puffins mate for life, and they have their own special way of showing affection.
0:02:24 > 0:02:26In this bleak environment,
0:02:26 > 0:02:29there's little in the way of building material for nests,
0:02:29 > 0:02:34so the puffins have to be resourceful to keep their little ones safe. If they can't build up,
0:02:34 > 0:02:35they dig down.
0:02:38 > 0:02:40- Hi.- Hi, Martin. How are you doing?
0:02:40 > 0:02:43Martin Scott, conservation officer with the RSPB,
0:02:43 > 0:02:45knows this colony well.
0:02:46 > 0:02:50- This slope is just littered with burrows, isn't it? - Yeah. Here's one just here.
0:02:50 > 0:02:52Looks promising, doesn't it?
0:02:52 > 0:02:55Do they come back to the same burrow every year?
0:02:55 > 0:02:59They do. They come back, clean it out and then re-line it
0:02:59 > 0:03:02with this nice sort of bed of dry grass.
0:03:02 > 0:03:04Puffins are really the perfect digging machine.
0:03:04 > 0:03:08They dig out very easily in the soft, peaty soil here so that's why
0:03:08 > 0:03:12- this embankment is covered in burrows.- There's also a large number nesting on the rocks.
0:03:12 > 0:03:17- Is there any advantage to that environment?- The rocks will be a lot more exposed, but they drain easier.
0:03:17 > 0:03:23Peaty soil has the potential to get waterlogged, although the peat can act as an insulator to the nests.
0:03:27 > 0:03:30Home life on the Shiant Islands is made even more agreeable
0:03:30 > 0:03:35by the rich pickings in the sea. The plankton-rich water is ideal
0:03:35 > 0:03:38if you're a great swimmer and love to eat small fish.
0:03:42 > 0:03:46This is the perfect place to get up close to these versatile birds
0:03:46 > 0:03:49and observe how well they perform under water.
0:03:52 > 0:03:55Watching them chase fish,
0:03:55 > 0:03:57their quirky body shape suddenly makes sense.
0:03:57 > 0:04:01Their wings act as fins and their webbed feet become a rudder,
0:04:01 > 0:04:05making them fly through the water with incredible grace.
0:04:08 > 0:04:11These puffins can dive to a depth of over 60 metres -
0:04:11 > 0:04:15that's as much as a 15-storey building!
0:04:15 > 0:04:18Although here, they only dive to around 20 metres
0:04:18 > 0:04:21to find the sand eels that they feed on.
0:04:24 > 0:04:26To snap their prey,
0:04:26 > 0:04:29they can reach speeds of five-and-a-half miles an hour.
0:04:30 > 0:04:36Seeing these birds under water, it's hard to believe they're also creatures of the sky,
0:04:36 > 0:04:39as slick as seals, but as flight-loving as seagulls.
0:04:39 > 0:04:44The puffins are totally at home here, both above and below the water line.
0:04:44 > 0:04:47Subtitles by Red Bee Media Ltd
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