Animals in Antarctica

Adélie Penguin Basics

Average Weight: 5kg - 11lb - feels more than this though when you've upset one and it's ran up and attacked you by hanging off your thigh muscle with its beak, like 5 bags of sugar dangling from a pair of pliers attached to your leg.
Average Height: 70cm - 27.5inches


Breeding Season: November - February - Adélie penguin colonies are very loud, raucous, busy and smelly affairs. The call of an adélie is as musical and gentle as a braying jackass and the whole colony is awash with guano (posh word for bird poop). When I was in Antarctica one thing I did was help with long-term surveys which entailed walking through the colony (terribly frowned upon these days). Each nest is just over two pecking distances apart so the penguins can't reach each other. Of course walking through the middle meant that you were in range of everyone. I used to worry a lot about falling over in a penguin colony, covered from head to toe in guano and pecked mercilessly.
Reproduction: Large colonies of up to half a million birds. Nests are lined with pebbles, and slightly higher than the surrounding land so that if the temperature rises and the snow melts, the nest is not flooded. The males arrive first on the nesting site at the beginning of the season and start the nest, then both partners work on the nest. Usually two eggs are laid, rarely three. Incubation of the first egg is 35 - 37 days, and the second chick is a few days behind the first. Male and female parent share egg and chick duty. Chicks are fed regurgitated krill (yum!) The chicks become independent at about two months old.
Estimated world population: - 5 million breeding pairs
Distribution: Circumpolar, tend to be found within the pack ice.
Oldest Rookery - At least 6,335 years old. The places where penguins nest together are called rookeries. These are started and later abandoned for reasons that are not entirely clear. Archaeological type studies have found that these rookeries are often continually used for many hundreds of years, even thousands. The oldest so far found has been used every year since well before 4 000 BC.
Adélie penguins are scared of: Leopard seals - main predators of adult birds, and Skuas - prey on eggs and chicks on land. They are not scared of the "Ice Man", "The Thing" or falling over on their backs and not being able to get up again - the first Antarctic "Urban Myth".

1/ Adélie penguins live further south than any other type. Why are these on the ice?.

There are more Adélie penguins than any other penguin species. They live in the deep south and as such frequently have to cross many kilometres of ice still bound to the continent or islands to reach land in the spring where they can build their nests.


Sometimes they have to travel as much as 100 kilometres, though usually 20-40 is more usual. A long walk nevertheless.
This pair were early arrivals in spring at an Antarctic Island near the northern edge of their breeding range and only had about half a kilometre to waddle and "toboggan".
Tobogganing is a way of getting around where there is smooth snow or ice. The penguin lies on its stomach and propels itself along using its feet, an efficient use of energy and one where the penguin can easily keep up with a running man.

2/ When do adélie penguins start to nest?

Adélies winter on the pack ice where the air temperature is higher than on land and where they can find cracks in the ice to fish through. In October, they begin to move south to their breeding grounds, the males arriving first to establish territories and nest spaces with the females arriving shortly afterwards. This is one of the first males arriving back in the spring before the remainder of the sea-ice has broken away.

3/ Why are these penguins hopping about on the ice?

These Adélies have a problem, they went out fishing at high tide and now. some hours later have returned. In the meantime the tide has gone out.   Still attached to the land is the "ice-foot" an ice step left behind as the tide rises and falls in the winter months to which the floating sea ice is loosely attached. When the sea ice breaks out, the ice-foot is left behind for a period of days to weeks before rising temperatures and the waves cause this to break off too. What was a short hop down for the penguins is now a step too high for them. I spent a couple of hours one afternoon watching and following an ever increasing number of penguins as they came back from their fishing trip. They wandered up and down the shore-line trying to find somewhere to get up, but to no avail. Eventually, the tide came back in and so they floated back up to the right level and were able to get back to their nests. The ice-foot broke off completely a few days later in a mild storm.

4/ How long were they stuck?

More of the Adélies stuck at low tide.   The ice-foot is more evident in this picture and the number of penguins is building up, by the time the tide was rising enough to float the grounded "bergy bits" that the birds are standing on, there were about 50 or so penguins standing around before they could get back up.

5/ Are there any problems in photographing penguins in these conditions?

This proved a difficult subject to capture on film.   A high contrast subject in bright light against a high contrast background poses an extreme problem in terms of exposure. The answer in this as in many other similar cases was to take an exposure reading off a neutral mid grey subject, set the camera for this and ignore anything the light meter told you when pointing at the real subject. After much experimentation, the ideal grey subject for metering turned out to be the pale grey moleskin  trousers that I wore (moleskin is a kind of thick warm cotton fabric, it's not really made from moles!). A very happy coincidence.

6/ Why is this penguin showing off?

What a handsome fellow! This male adélie is a bit late compared to the others around him who have in the main already paired and nested.   The males arrive at the breeding grounds first, find a good spot and then go through this display with much raucous calling and flipper waving to attract a suitably impressed female. (A similar ritual is re-enacted on Friday and Saturday evenings at bars and clubs the world over) This shot also shows the half-feathered beak characteristic of Adélie and how stocky and powerful they are despite their diminutive stature. A friend I was with on a similar occasion was attacked by an unhappy adélie that had decided he was too close to the nest. My friend described it as "..like having 5kg of solid muscle hanging from your skin by a pair of pliers" - don't try this at home.

7/ Adelie penguins (Pygoscelis adeliae) tobogganing

Tobogganing Adelie penguins (and a lone chinstrap in the fore-ground). All types of penguin that come across snow and ice can and will toboggan in this manner. It is a very efficient and rapid way of moving when the conditions are right - soft snow, but where the penguin only sinks a little way into it, needing less energy than walking the same distance. The penguin lays on it's front and pushes its way forwards using its feet, the flippers are used for balance or sometimes as oars to help forwards movement. A considerable speed can be reached for short distances in this way, enough to out pace a running man.

8/ Penguin dive

Antarctic penguins run a constant risk when entering or leaving the water from the almost ever-present danger of their main predator, the leopard seal. Leopard seals tend not to chase penguins in open sea, but hang around the places where they jump into the sea from their nesting areas, or where they leave the sea again as this is gives much more productive hunting. This gives the penguins a problem when going into the sea, they have to enter it to go fishing and to get places, but being the first one in means that they're first in line for any potential leopard seals. Hanging back isn't any better though as they may get left behind and end up jumping in on their own. What happens therefore is that they gather at the edge of the water becoming quite animated and jostling for position until one near to the edge gets pushed or jumps in - that's the signal for the rest, as the odds of survival are far greater when you're part of a large group, they then all dive in in rapid succession.

9/ Surprise! - where did you come from?

These penguins were walking, waddling and tobogganing up and down the area beneath the ice foot looking somewhere to get out. So I thought I'd play a little trick, squat down out of view and wait for them to turn the corner - no I didn't jump up and shout "surprise!", but the comic effect of the first bird's reaction to realising he was coming towards me at high speed is evident. Fortunately I managed to get this shot off and capture the moment before moving sea-wards (to the left) and allowing their progress to continue, they were back again a few minutes later though as all they could really do was wait for the tide to come in and raise them up to the right level.

10/ Is this a penguin? Wait until his father gets home!

When the parents go off to sea to catch fish for the chicks, the chicks have little to do other than stand around and try not to get into trouble.  This doesn't always work in the way that it is supposed to, rather like human children, penguin chicks fall over sometimes and get a bit dirty!

1/ What are Weddell seals like?

Weddell seals are animals of the ice. They live further south than any other mammal. Between the end of August and early November in the southern hemisphere spring, the mother seals to be haul themselves out of holes in the ice and give birth to their pups. When born, Weddell seal pups look like unstuffed pyjama cases, all skin and flippers and not much content. Over the next few weeks the change in mother and pup is like one balloon deflating and filling up another. Weddell seals are animals of the ice.

2/ How do Weddell mothers look after their young?

Newly born Weddell seal pups have to be some of the worlds cutest creatures as they flop about the ice in the early days after their birth, not able to co-ordinate their over-sized flippers before they grow into them.   The mother arrives pregnant and with enough resources of blubber and protein to double the 25kg (55lb) birth weight of a pup in 10 days. She doesn't feed for about the first month and goes from an extremely plump barrel shape just before she gives birth - to a skinny shadow of her former self with ribs visible while the pup reverses the process.

3/ Isn't it difficult for the pups to survive when they're born onto the ice?

Weddell seal milk is one of the richest produced by any mammal. It contains about 60% fat (go and compare that to the label on the milk carton in the fridge) and it is this that is responsible for the rapid weight gain made by pups shortly after birth.   The pups are weaned (stop drinking milk and begin eating normal seal food, i.e. fish) at around 7 weeks when they should have reached about 110kg (242lb). When adult, they will weigh up to 400kg (880lb) and be up to 3m (10ft) long. Unusually, the males are slightly smaller than the females. Pups are encouraged into the water very early on by their mothers, perhaps only a week or so after birth. The water is their natural habitat and with their thick protection of blubber is a more comfortable place to be most of the time for these seals than out on the ice where the temperature can be -40° C or less with winds frequently of gale force or greater.

4/ Why do they have such large eyes?

Weddell seals live on the edge of the ice all year round and dive down beneath it to feed. When underwater there is frequently little light, particularly if there is a layer of snow over the ice which can make it very dark indeed. The seals therefore need good vision to catch their food.

5/ Where are the males when the pups are born and suckling from the mother?

Weddell seals usually have their pups on sea-ice, getting in and out of the sea through a breathing hole. These breathing holes are guarded and kept open by the males during the time when the females give birth.   The male guarding the hole will defend a territory beneath the ice against other males for access to mates. The females are ready to breed again shortly after the birth of the pup so the males that successfully defend a breathing hole will mate with the mother seals that use this hole, typically this will be a ratio of about 10 to one.

6/ How do Weddell seals manage to survive out on the open ice? How do they get to the sea?

Weddell seals prefer to live on ice that is broken up somewhat, in this way there are often natural cracks and holes through the ice that they can use to get in and out of the sea. There are also holes and cracks around ice bergs that are trapped in sea-ice and often "tide-cracks" appear near when near land, all of these help.These holes are fine to begin with, but when temperatures are well below freezing, they begin to freeze up - quickly. The seals keep the holes open by rasping them with their teeth. They open their mouths wide and move their heads back and forward in a wide arc attacking the ice that is building up around the sides of the hole. This is a very fast and vigorous process that takes a lot of energy and a toll on the seals teeth. Keeping breathing holes open like this wears away the teeth of Weddell seals and it is this that means that the Weddells only live to about 18 years old, about half the life-span of a crabeater seal for instance. Weddells can swim great distances across apparently continuous sea-ice by detecting the natural cracks and holes along the way. When covering distance rather than fishing, they only dive to a shallow depth and find the next breathing hole in the gloom under the ice by sonar - they emit a series of high pitched sounds and pick up the difference in sound when the sounds reach a hole.

7/ Do the pups take naturally to the water straight away?

The first picture is of a juvenile Weddell seal  weaned from its mother about 2 or 3 months previously and already completely in control in its aquatic environment.   The scene a few months ago was rather different though. Weddell seal pups don't automatically realise that they can or should dive and the early attempts are amusing to watch. "Attempts" is the wrong word. What actually happens is that the mother pushes the pup into the water against its will. She then pushes its head under the water - again against its will. There is much coughing, spluttering and panic before the pup realises that it can hold its breath under the water and that this in fact does help! The pups soon get the hang of it though and as adults will dive to up to 600 metres (2 000ft) or more staying under for up to an hour and going as much as 12 kilometres from the breathing hole. A typical feeding dive takes the seal to 200-400m and lasts for 5-25 minutes.

8/ Weddell Seal (Leptonychotes wedelli) at breathing holes

Weddell seals are very hardy, resourceful and quite remarkably behaviourally adapted for life in the Antarctic pack and fast-ice as these two pictures show. In the top picture, the seal has found a breathing hole through pieces of only partially consolidated pack-ice where there is a non-frozen portion that is nonetheless filled with slush. From below such a region will let considerably more light through than the thick pack-ice pieces and stand out like a beacon to a seal swimming by, even if it is solid, it will be thin and probably thin enough for the seal to break through. Weddell seals have no land-based predators and so there is no danger to them of coming up to such breathing holes, just the odd surprise if there's a wandering scientist nearby to capture the moment on camera. The lower picture is of a Weddell seal that has made a hole in apparently unbroken, though quite thin fast-ice and hauled out for a rest. We came across this seal while out several miles from the shore on recently formed and very hard and strong, but disconcertingly thin ice. In fact we didn't realise how thin the ice was until we came across this seal and the hole it had made. It was entirely unperturbed by a group of 5 people manhauling a heavily laden sledge with camping gear as we went off on our holidays and treated us as if we weren't really there at all. Seals probably live a fairly surreal life anyhow.

9/ Why are the White Island Weddell seals special?

White Island is an Island in the Ross sea that has the most southerly population of Weddell seals. These seals are only 1 300 kilometres from the South Pole, but this is not the only remarkable thing about them.
They are isolated from the rest of the world as the nearest open sea for them to is too far under the very thick ice of the Ross ice shelf for them to get out.
These seals are thought to have travelled to this area between 50 and 100 years ago when a large chunk of permanent ice shelf broke off. They were then trapped when it reformed behind them and have remained here ever since. They use cracks in the ice immediately beside White Island to reach the sea, they must dive about 70 metres here through cracks in the ice before they get down to the open sea below. In the summer when the sea ice has broken up, it is still at least 22 kilometres to the next breath at the edge of the ice shelf, too far for the seals to manage.
So here they remain unable to leave the area and with a deep dive past walls of ice before they can even begin fishing.