Eider Ducks
For thousands of years people have been kept warm by the miraculous insulating powers of the sustainably harvested down of a very special type of duck
Marvel at this bird’s miraculous insulating powers
Iknew the word ‘Eiderdown’ long before I knew what an Eider was. When I was very young, my older relatives used it as another word for a duvet, and I didn’t question it any more than I question the word duvet today. Later, when I learned what an Eider was, I still failed to put the two together. In fact, it wasn’t until a recent trip to Iceland that I finally made the link, while at the same time discovering that my older relatives had drastically oversold the quality of their bedding.
The Eider is a distinctive looking duck. The males are large and strong, with a vivid black and white pattern and a patch of yellowish green on the nape. They have a black cap that makes their eye invisible and a long, sloped yellow bill. The females are a little less impressive, with a simple plumage, but the same elongated, sloping bill that makes them easy to identify.
Even if the males didn’t look as distinct as they do, the size might also give them away. The Eider is the heaviest duck in Europe, with an average weight of around
two kilograms (our smallest duck is the Teal, which weighs in at around 350g). Despite its size, the bird is also agile, even athletic. For a start, it’s extremely fast in flight. Eider have been clocked at speeds of up to 70mph, making it one of the fastest birds in the world in level flight (that’s not just out of ducks, by the way, it’s out of all birds). Its aerial ability is matched by its aquatic aptitude.
Eiders can dive to depths of up to 20 metres to scour the ocean floor for crustaceans and molluscs. These are swallowed whole, including shells, which are crushed in the gizzard and excreted.
Superpower
Despite these impressive statistics, it isn’t athleticism that has given the Eider its renown. For that, we have to return to the female Eider, which has a kind of superpower that sets it apart from any other bird.
The Eider’s Latin name, Somateria mollissima, comes from the Greek words meaning something like ‘body wool very soft’. This name refers to ‘down’ feathers, which Eider, like most birds, have beneath the outer or vaned feathers, and which help to keep birds warm by trapping a layer of heated air close to the body. The down feathers are most visible on chicks, which are entirely covered with them, before the vaned feathers grow in.
If you look at a vaned feather through a microscope, you’ll see a series of tightly linked hairs stemming from a hard central spine. If you look at Eider down through a microscope, you’ll see a soft tangled fluff,
with no hard spine, but rather soft wispy branches spreading out in all directions.
On each branch are tiny hooks that help the down to cling together, but also trap pockets of air that are heated by the bird’s body. This structure makes the Eider down extremely collapsible and the best insulator known to man. Synthetic or natural, there is no material on earth that can match the warmth-toweight ratio of Eider down.
People, naturally, were quick to realise this and Eider down has been used as an insulator for thousands of years. It is still farmed today, though ‘farmed’ isn’t quite the right word, more like traded.
Around 75% of the world’s Eider down is collected in Iceland, with the rest coming from Norway, Canada, Denmark and Greenland. The way it works is simple. A farmer will cultivate a field on a coastline where the Eider is known to nest – some farmers even go as far as making small huts in which the Eider can find added protection from the elements.
In spring, the birds arrive. The Eider is a social bird and so sometimes hundreds of birds will call the same field home. The male will be present, too, sitting by the female while she lays and incubates like a father in the waiting room of a maternity ward.
The females make a nest from down feathers plucked from its breast into which they will lay up to six eggs (a book from the late 1920s about the nesting habits of the Eider on Orkney, suggested that the eggs are first laid on a bed of heather and grass, and that absolutely no down is plucked until the third egg has been laid, at which point the plucking begins. I couldn’t find any additional source, so I can’t vouch for it, but it’s a nice anecdote and may well be true).
The incubation period lasts up to 25 days, during which time the females will not leave the nest, even to eat. While the birds are incubating, the farmers will be diligently working behind the scenes to protect the colony from predators, primarily Arctic Fox, mostly through the
THE WORLDWIDE POPULATION OF EIDER ONLY PRODUCES AROUND FOUR METRIC TONS OF DOWN PER YEAR...
construction and maintenance of strong fences, though there is, sadly, some shooting involved.
Valuable harvest
Other than that, the Eiders are left entirely alone. Any disturbance could cause the female to flee, but not before she has secreted oily excrement on the eggs intended to put off any predators, but which could also ruin the valuable down nest.
When the chicks hatch, the female leads them down to the sea, where they will team up with other new families to form large ‘crèches’, in which a couple of adult females will guard the collection of chicks, while others forage for food.
Though Eiders often nest in the same area, they build a new nest each year and so, once the chicks have fledged, the old nest is waste material to the duck.
It’s at this point that the farmer steps in and collects the valuable harvest, which is dried, cleaned and prepared for sale.
The duck loses nothing, in fact, it increases its chance of a successful nest by being on land protected by the farmer, and the farmer keeps the nest in exchange. It’s perhaps the most symbiotic relationship in the animal-human world.
The worldwide population of Eider only
produces around four metric tons of down per year, which is only enough to make about 4,000 duvets. This scarcity coupled with the extraordinary insulating properties makes Eider down extremely expensive. To give you an idea, if you wanted to buy a 100% Eider down duvet you should be prepared to spend a little over £ 8,000 at the time of writing (so I suspect my family’s ‘Eiderdowns’ weren’t the real deal!). In the UK, Eider can be seen year round; in summer, in Scotland, Northern Ireland and the north of England, and in winter all around the coastline. They’re exclusively a sea duck and will almost never be on freshwater.
There’s a particularly interesting colony of Eider on the Farne Islands in Northumberland. This colony has been in continuous presence for well over a thousand years. In fact, they were the subject of one of the world’s first bird conservation ordinances, when an influential monk called Saint Cuthbert ordered that the Eider not be harmed or disturbed. This may be a lovely bit of trivia, but should perhaps be taken with a pinch of salt.
The first account linking Saint Cuthbert and the Eider was written in the 12th Century, 500 years after his death (there is also a story in which the holy man submerged himself in the sea to pray, and when he got out two Otters dried his feet with their fur – as I said, a pinch of salt).
At the very least, the story links the Eider with the Farne Islands and suggests at its close connection with humans. In Northumberland, Eiders are still referred to as Cuddy Ducks.
The human relationship to birds isn’t always very comforting. We, at various times, eat them, hunt them, trap them and poison them – and the way goose down is obtained, often through ‘live plucking’, is shocking, cruel and should be swiftly banned. In this landscape of abuse, there is something deeply comforting about our long relationship with the Eider.
While we have been so callous and often cruel to so many species of birds, it’s nice to think that for thousands of years, without even knowing it, we’ve kept these wonderful creatures safe and in exchange they have kept us warm.