This puffin has a black crown and back, pale grey cheek patches and white underparts. Its broad, boldly marked red and black beak and orange legs contrast with its plumage. It moults while at sea in the winter and some of the bright-coloured facial characteristics are lost, with color returning again during the spring. The external appearance of the adult male and female are identical though the male is usually slightly larger. The juvenile has similar plumage but its cheek patches are dark grey. The juvenile does not have brightly coloured head ornamentation, its bill is narrower and is dark-grey with a yellowish-brown tip, and its legs and feet are also dark. Puffins from northern populations are typically larger than in the south and it is generally considered that these populations are different subspecies.
Spending the autumn and winter in the open ocean of the cold northern seas, the Atlantic puffin returns to coastal areas at the start of the breeding season in late spring. It nests in clifftop colonies, digging a burrow in which a single white egg is laid. The chick mostly feeds on whole fish and grows rapidly. After about six weeks it is fully fledged and makes its way at night to the sea. It swims away from the shore and does not return to land for several years.
Colonies are mostly on islands where there are no terrestrial predators but adult birds and newly fledged chicks are at risk of attacks from the air by gulls and skuas. Sometimes a bird such as an Arctic skua will harass a puffin arriving with a beakful of fish, causing it to drop its catch. The striking appearance, large colourful bill, waddling gait and behaviour of this bird have given rise to nicknames such as "clown of the sea" and "sea parrot". It is the official bird symbol for the Canadian province of Newfoundland and Labrador.
In 2015, the International Union for Conservation of Nature changed its status from "Least Concern" to "Vulnerable".[1] In 2018, BirdLife International reported that the Atlantic puffin was threatened with extinction.[2]
Taxonomy and etymology
Charadriiformes. It is in the auk family, Alcidae, which includes the guillemots, typical auks, murrelets, auklets, puffins and the razorbill.[4] The rhinoceros auklet (Cerorhinca monocerata) and the puffins are closely related, together composing the tribe Fraterculini.[5] The Atlantic puffin is the only species in the genus Fratercula to occur in the Atlantic Ocean. Two other species are known from the northeast Pacific, the tufted puffin (Fratercula cirrhata) and the horned puffin (Fratercula corniculata), the latter being the closest relative of the Atlantic puffin.[6]The scientific name Fratercula comes from the Medieval Latin fratercula, friar, a reference to the black and white plumage which resembles monastic robes.[7] The specific name arctica refers to the northerly distribution of the bird, being derived from the Greek ἄρκτος ("arktos"), the bear, referring to the northerly constellation, the Great Bear.[8] The vernacular name puffin – puffed in the sense of swollen – was originally applied to the fatty, salted meat of young birds of the unrelated species Manx shearwater (Puffinus puffinus), which in 1652 was known as the "Manks puffin".[9] It is an Anglo-Norman word (Middle English pophyn or poffin) used for the cured carcasses.[10] The Atlantic puffin acquired the name at a much later stage, possibly because of its similar nesting habits,[11] and it was formally applied to Fratercula arctica by Pennant in 1768.[9] While the species is also known as the common puffin, "Atlantic Puffin" is the English name recommended by the International Ornithological Congress.[12]
There are considered to be three subspecies:[13]
- Fratercula arctica arctica
- Fratercula arctica grabae
- Fratercula arctica naumanni
Description
Adult puffins have boldly coloured beaks in the breeding season.
The beak is very distinctive. From the side the beak is broad and triangular but viewed from above it is narrow. The half near the tip is orange-red and the half near to the head is slate grey. There is a yellow chevron-shaped ridge separating the two parts and a yellow, fleshy strip at the base of the bill. At the joint of the two mandibles there is a yellow, wrinkled rosette. The exact proportions of the beak vary with the age of the bird. In an immature individual, the beak has reached its full length but it is not as broad as that of an adult. With time the bill deepens, the upper edge curves and a kink develops at its base. As the bird ages, one or more grooves may form on the red portion.[16] The bird has a powerful bite.[17]
Appearance of beak and eyes during the breeding season (left) and after the moult (right; lettered items have been shed)
The Atlantic puffin has a direct flight, typically 10 metres (33 ft) above the sea surface and higher over the water than most other auks.[20] It mostly moves by paddling along efficiently with its webbed feet and seldom takes to the air.[21] It is typically silent at sea, except for the soft purring sounds it sometimes makes in flight. At the breeding colony it is quiet above ground but in its burrow makes a growling sound somewhat resembling a chainsaw being revved up.[22]
Distribution
The Atlantic puffin is a bird of the colder waters of the North Atlantic Ocean. It breeds on the coasts of north west Europe, the Arctic fringes and eastern North America. More than 90% of the global population is found in Europe (4,770,000–5,780,000 pairs, equalling 9,550,000–11,600,000 adults)[1] and colonies in Iceland alone are home to 60% of the world's Atlantic puffins. The largest colony in the western Atlantic (estimated at more than 260,000 pairs) can be found at the Witless Bay Ecological Reserve, south of St. John's, Newfoundland and Labrador.[23] Other major breeding locations include the north and west coasts of Norway, the Faroe Islands, the Shetland and Orkney islands, the west coast of Greenland and the coasts of Newfoundland. Smaller sized colonies are also found elsewhere in the British Isles, the Murmansk area of Russia, Novaya Zemlya, Spitzbergen, Labrador, Nova Scotia and Maine. Islands seem particularly attractive to the birds for breeding as compared to mainland sites.[24]While at sea, the bird ranges widely across the North Atlantic Ocean, including the North Sea, and may enter the Arctic Circle. In the summer, its southern limit stretches from northern France to Maine and in the winter the bird may range as far south as the Mediterranean Sea and North Carolina. These oceanic waters have such a vast extent of 15 to 30 million square kilometres (6 to 12 million square miles) that each bird has more than a square kilometre at its disposal and it is unsurprising that they are seldom seen out at sea.[25] In Maine, light level geolocators have been attached to the legs of puffins which store information on their whereabouts. The birds need to be re-captured in order to access the information, a difficult task. One bird was found to have covered 4,800 miles (7,700 km) of ocean in eight months, traveling northwards to the northern Labrador Sea then southeastward to the mid-Atlantic before returning to land.[17]
In a long-living bird with a small clutch size such as the Atlantic puffin, the survival rate of adults is an important factor influencing the success of the species. Only 5% of the ringed puffins that failed to reappear at the colony did so during the breeding season. The rest were lost some time between departing from land in the summer and reappearing the following spring. The birds spend the winter widely spread out in the open ocean, though there is a tendency for individuals from different colonies to overwinter in different areas. Little is known of their behaviour and diet at sea but no correlation was found between environmental factors, such as temperature variations, and their mortality rate. A combination of the availability of food in winter and summer probably influences the survival of the birds, since individuals starting the winter in poor condition are less likely to survive than those in good condition.[26]
Behaviour
Like many seabirds, the Atlantic puffin spends most of the year far from land in the open ocean and only visits coastal areas to breed. It is a sociable bird and it usually breeds in large colonies.[27]At sea
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A running takeoff at Bear Island (Norway).
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Bobbing about on the waves off the coast of northern Norway
When it takes off, the Atlantic puffin patters across the surface of the water while vigorously flapping its wings, before launching itself into the air.[18][21] The size of the wing has adapted to its dual use, both above and below the water, and its surface area is small relative to the bird's weight. To maintain flight, the wings need to beat very rapidly at a rate of several times each second.[28] The bird's flight is direct and low over the surface of the water and it can travel at 80 kilometres (50 mi) per hour. Landing is awkward; it either crashes into a wave crest or, in calmer water, does a belly flop. While at sea, the Atlantic puffin has its annual moult. Land birds mostly lose their primaries one pair at a time to enable them still to be able to fly, but the puffin sheds all its primaries at one time and dispenses with flight entirely for a month or two. The moult usually takes place between January and March but young birds may lose their feathers a little later in the year.[21]
Food and feeding
The Atlantic puffin diet consists almost entirely of fish, though examination of its stomach contents shows that it occasionally eats shrimps, other crustaceans, molluscs and polychaete worms, especially in more coastal waters.[29] When fishing, it swims underwater using its semi-extended wings as paddles to "fly" through the water and its feet as a rudder. It swims fast and can reach considerable depths and stay submerged for up to a minute. It can eat shallow-bodied fish as long as 18 cm (7 in) but its prey is commonly smaller fish, around 7 cm (3 in) long. It has been estimated that an adult bird needs to eat about forty of these per day—sand eels, herring, sprats and capelin being the most often consumed. It fishes by sight and can swallow small fish while submerged, but larger specimens are brought to the surface. It can catch several small fish in one dive, holding the first ones in place in its beak with its muscular, grooved tongue while it catches others. The two mandibles are hinged in such a way that they can be held parallel to hold a row of fish in place and these are also retained by inward-facing serrations on the edges of the beak. It copes with the excess salt that it swallows partly through its kidneys and partly by excretion through specialised salt glands in its nostrils.[21]On land
Atlantic puffins on a cliff-top at Skellig Michael, County Kerry, Ireland
Relaxation in the colony
Establishing dominance
Pair outside burrow on Skomer Island, Wales
The puffins are energetic burrow-engineers and repairers and the grassy slopes may be undermined by a network of tunnels. This causes the turf to dry out in summer, vegetation to die and dry soil be whirled away by the wind. Burrows sometimes collapse, and humans may cause this to happen by walking incautiously across nesting slopes. A colony on Grassholm was lost through erosion when there was so little soil left that burrows could not be made.[32] New colonies are very unlikely to start up spontaneously because this gregarious bird will only nest where others are already present. Nevertheless, the Audubon Society had success on Eastern Egg Rock Island in Maine, where, after a gap of ninety years, puffins were reintroduced and started breeding again. By 2011 there were over 120 pairs nesting on the small islet.[33] On the Isle of May on the other side of the Atlantic, only five pairs of puffins were breeding in 1958 while twenty years later there were 10,000 pairs.[34]
Reproduction
Typical Atlantic puffin breeding habitat in Iceland
The Atlantic puffin is sexually mature at the age of four to five years. The birds are colonial nesters, excavating burrows on grassy clifftops or reusing existing holes, and on occasion may nest in crevices and among rocks and scree. It is in competition with other birds and animals for burrows. It can excavate its own hole or move into a pre-existing system dug by a rabbit and has been known to peck and drive off the original occupant. Manx shearwaters also nest underground and often live in their own burrows alongside puffins, and their burrowing activities may break through into the puffin's living quarters resulting in the loss of the egg.[36] They are monogamous (they mate for life) and give biparental care to their young. The male spends more time guarding and maintaining the nest while the female is more involved in incubation and feeding the chick.[37]
Egg-laying starts in April in more southerly colonies but seldom occurs before June in Greenland. The female lays a single white egg each year but if this is lost early in the breeding season, another might be produced.[38] Synchronous laying of eggs is found in Atlantic puffins in adjacent burrows.[39] The egg is large compared to the size of the bird, averaging 61 millimetres (2.4 in) long by 42 millimetres (1.7 in) wide and weighing about 62 grams (2.2 oz). The white shell is usually devoid of markings but soon becomes soiled with mud. The incubation responsibilities are shared by both parents. They each have two feather-free brood patches on their undersides where an enhanced blood supply provides heat for the egg. The parent on incubation duty in the dark nest chamber spends much of its time asleep with its head tucked under its wing, occasionally emerging from the tunnel to flap dust out of its feathers or take a short flight down to the sea.[38]
Egg at Museum Wiesbaden Germany
Adult returning with sand eels to feed the chick
Hunting areas are often located 100 km (60 mi) or more, offshore from the nest sites, although when feeding their young, the birds venture out only half that distance.[41] It has been found that adults bringing fish to their chicks tend to arrive in groups. This is thought to benefit the bird by reducing kleptoparasitism by the Arctic skua which harasses puffins until they drop their fish loads. Predation by the great skua (Catharacta skua) is also reduced by several birds arriving simultaneously.[42]
Nearly fully fledged, near its burrow and at risk of predation
Juvenile recently emerged from the nest
The chicks take from 34 to 50 days to fledge, the period depending on the abundance of their food supply. In years of fish shortage, the whole colony may experience a longer fledgling period but the normal range is 38 to 44 days, by which time chicks will have reached about 75% of their mature body weight. The chick may come to the burrow entrance to defecate but does not usually emerge into the open[46] and seems to have an aversion to light until it is nearly fully fledged.[47] Although the supply of fish by the adults reduces over the last few days spent in the nest, the chick is not abandoned as happens in the Manx shearwater. On occasions, an adult has been observed provisioning a nest even after the chick has departed. During the last few days underground, the chick sheds its down and the juvenile plumage is revealed. Its relatively small beak and its legs and feet are a dark colour and it lacks the white facial patches of the adult. The chick finally leaves its nest at night, when the risk of predation is at its lowest. When the moment arrives, it emerges from the burrow, usually for the first time, and walks, runs and flaps its way to the sea. It cannot fly properly yet so descending a cliff is perilous; when it reaches the water it paddles out to sea, and may be three kilometres (two miles) away from the shore by daybreak. It does not congregate with others of its kind and will not return to land for two or three years.[46]
Predators and parasites
Atlantic puffins are probably safest when out at sea. Here, the dangers are often from below the water rather than above, and puffins can sometimes be seen putting their heads underwater to peer around for predators. Seals have been known to kill puffins and large fish may also do so. Most puffin colonies are on small islands, and this is no coincidence as it avoids predation by ground-based mammals such as foxes, rats, stoats and weasels, cats and dogs. When they come ashore, the birds are still at risk and the main threats come from the sky.[48]Aerial predators of the Atlantic puffin include the great black-backed gull (Larus marinus), the great skua (Stercorarius skua), and similar-sized species, which can catch a bird in flight, or attack one that is unable to escape fast enough on the ground. On detecting danger, puffins take off and fly down to the safety of the sea or retreat into their burrows, but if caught they defend themselves vigorously with beak and sharp claws. When the puffins are wheeling round beside the cliffs it becomes very difficult for a predator to concentrate on a single bird while any individual isolated on the ground is at greater risk.[49] Smaller gull species like the herring gull (L. argentatus) and the lesser black-backed gull are hardly able to bring down a healthy adult puffin. They stride through the colony taking any eggs that have rolled towards burrow entrances or recently hatched chicks that have ventured too far towards the daylight. They will also steal fish from puffins returning to feed their young.[50] Where it nests on the tundra in the far north, the Arctic skua (Stercorarius parasiticus) is a terrestrial predator, but at lower latitudes it is a specialised kleptoparasite, concentrating on auks and other seabirds. It harasses puffins while they are airborne forcing them to drop their catch which it then snatches up.[51]
Both the guillemot tick Ixodes uriae and the flea Ornithopsylla laetitiae (probably originally a rabbit flea) have been recorded from the nests of puffins. Other fleas which have been found on the birds include Ceratophyllus borealis, Ceratophyllus gallinae, Ceratophyllus garei, Ceratophyllus vagabunda and the common rabbit flea Spilopsyllus cuniculi.[52]
Relationship with humans
Status and conservation
In flight over the Isle of May, Scotland
On the other hand, puffin numbers increased considerably in the late twentieth century in the North Sea, including on the Isle of May and the Farne Islands where numbers increased by about 10% per year. In the 2013 breeding season, nearly 40,000 pairs were recorded on the Farne Islands, a slight increase on the 2008 census and on the previous year's poor season when some of the burrows flooded.[56] This number is dwarfed by the Icelandic colonies with five million pairs breeding, the Atlantic puffin being the most populous bird on the island.[57] In the Westman Islands, where about half Iceland's puffins breed, the birds were almost driven to extinction by overharvesting around 1900 and a thirty-year ban on hunting was put in place. When stocks recovered, a different method of harvesting was used and now hunting is maintained at a sustainable level.[58] Nevertheless, a further hunting ban covering the whole of Iceland was called for in 2011, although the puffin's lack of recent breeding success was being blamed on a diminution in food supply rather than overharvesting.[59] Since 2000, a sharp population decline has been seen in Iceland, Norway, Faroe Islands and Greenland.[1] A similar trend has been seen in the United Kingdom, where an increase in 1969-2000 appears to have been reversed.[1] For example, the Fair Isle colony was estimated at 20,200 individuals in 1986, but it had been almost halved by 2012.[1] Based on current trends, it is estimated that the European population will decline by 50-79% between 2000 and 2065.[1]
SOS Puffin is a conservation project at the Scottish Seabird Centre at North Berwick to save the puffins on islands in the Firth of Forth. Puffin numbers on the island of Craigleith, once one of the largest colonies in Scotland with 28,000 pairs, have declined dramatically to just a few thousand due to the invasion of a large introduced plant, the tree mallow (Lavatera arborea). This has spread across the island in dense thickets and prevents the puffins from finding suitable sites for burrowing and breeding. The project has the support of over 700 volunteers and progress has been made in cutting back the plants, with puffins returning in greater numbers to breed.[60] Another conservation measure undertaken by the Centre is to encourage motorists to check under their cars in late summer before driving off as young puffins, disorientated by the street lights, may land in the town and take shelter underneath the vehicles.[61]
Project Puffin is an effort initiated in 1973 by Dr. Stephen W. Kress of the National Audubon Society to restore Atlantic puffins to nesting islands in the Gulf of Maine. Eastern Egg Rock Island in Muscongus Bay, about 6 miles (9.7 km) away from Pemaquid Point, had been occupied by nesting puffins until 1885, when the birds disappeared because of overhunting. Counting on the fact young puffins usually return to breed on the same island where they fledged, a team of biologists and volunteers translocated 10–14 days old nestlings from Great Island in Newfoundland to Eastern Egg Rock. The young were placed into artificial sod burrows, and fed with vitamin-fortified fish daily for about one month. Such yearly translocations took place until 1986, with 954 young puffins being moved in total. Each year before fledging, the young were individually tagged. The first adults returned to the island by 1977. Puffin decoys had been installed on the island to fool the puffins into thinking they were part of an established colony. This did not catch on at first, but in 1981 four pairs nested on the island. In 2014, 148 nesting pairs were counted on the island. In addition to demonstrating the feasibility of re-establishing a seabird colony, the project showed the usefulness of using decoys, and eventually call recordings and mirrors, to facilitate such reestablishment.[62]
Pollution
Since the Atlantic puffin spends its winters on the open ocean, it is susceptible to human actions and catastrophes such as oil spills. Oiled plumage has a reduced ability to insulate and makes the bird more vulnerable to temperature fluctuations and less buoyant in the water.[63] Many birds die, and others, while attempting to remove the oil by preening, ingest and inhale toxins. This leads to inflammation of the airways and gut and in the longer term, damage to liver and kidneys. This trauma can contribute to a loss of reproductive success and harm to developing embryos.[39] An oil spill occurring in winter, when the puffins are far out at sea, may affect them less than inshore birds as the crude oil slicks soon get broken up and dispersed by the churning of the waves. When oiled birds get washed up on beaches around Atlantic coasts, only about 1.5% of the dead auks are puffins, but many others may have died far from land and sunk.[64] After the oil tanker Torrey Canyon shipwreck and oil spill in 1967, few dead puffins were recovered, but the number of puffins breeding in France the following year was reduced to 16% of its previous level.[65]The Atlantic puffin and other pelagic birds are excellent bioindicators of the environment as they occupy a high trophic level. Heavy metals and other pollutants are concentrated through the food chain and, as fish are the primary food source for Atlantic puffins, there is great potential for them to bioaccumulate heavy metals such as mercury and arsenic. Measurements can be made on eggs, feathers or internal organs and beached bird surveys, accompanied by chemical analysis of feathers, can be effective indicators of marine pollution by lipophilic substances as well as metals. In fact these surveys can be used to provide evidence of the adverse effects of a particular pollutant, using fingerprinting techniques to provide evidence suitable for the prosecution of offenders.[66][67]
Climate change
Climate change may well affect populations of seabirds in the northern Atlantic. The most important demographic may be an increase in the sea surface temperature which may have benefits for some northerly Atlantic puffin colonies.[68] Breeding success depends on there being ample supplies of food at the time of maximum demand, as the chick grows. In northern Norway the main food item fed to the chick is the young herring. The success of the newly hatched fish larvae during the previous year was governed by the water temperature, which controlled plankton abundance and this in turn influenced the growth and survival of the first-year herring. The breeding success of Atlantic puffin colonies has been found to correlate in this way with the water surface temperatures of the previous year.[69]In Maine, on the other side of the Atlantic, shifting fish populations due to changes in sea temperature are being blamed for the lack of availability of the herring which is the staple diet of the puffins in the area. Some adult birds have become emaciated and died. Others have been provisioning the nest with butterfish (Peprilus triacanthus) but these are often too large and deep-bodied for the chick to swallow, causing it to die from starvation. Maine is on the southerly edge of the bird's breeding range and with changing weather patterns, this may be set to contract northwards.[70]
Tourism
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Approaching nesting birds too closely may jeopardise the colony
Hunting
Puffin hunters, Faroe Islands, 1898 or 1899
On Stóra Dímun, puffins are still important food today.
Traditional means of capture varied across the birds' range and nets and rods were used in various ingenious ways. A typical device used in the Faroes was a "fleyg". This was a long pole with a net on the end laid flat on the ground. A few dead puffins were strewn around to entice incoming birds to land, and the net was flicked upwards to scoop a bird from the air as it slowed before alighting. Most of the birds caught were sub-adults, and a skilled hunter could gather two or three hundred in a day. Another method of capture, used in St Kilda, involved the use of a flexible pole with a noose on the end. This was pushed along the ground towards the intended target, which advanced to inspect the noose as its curiosity overcame its caution. A flick of the wrist would flip the noose over the victim's head and it was promptly killed, before its struggles could alarm other birds nearby.[76]
In culture
Faroe Islands 1978 postal stamp by Holger Philipsen
A number of islands have been named after the bird. The island of Lundy in the United Kingdom is reputed to derive its name from the Norse lund-ey or "puffin island".[81] An alternative explanation has been suggested connected with another meaning of the word lund referring to a copse or wooded area. The Vikings might have found the island a useful refuge and restocking point after their depredations on the mainland .[82] The island issued its own coins and, in 1929, its own stamps with denominations in "puffins".[83] Other countries and dependencies which have depicted Atlantic puffins on their stamps include Alderney, Canada, the Faroe Islands, France, Gibraltar, Guernsey, Iceland, Ireland, the Isle of Man, Jersey, Norway, Portugal, Russia, Slovenia, St Pierre et Miquelon and the United Kingdom.[84] The LPO, a French biodiversity charity focussing on the protection of birds, uses a pair of Atlantic puffins as its emblem.[85]
The publisher of paperbacks, Penguin Books, introduced a range of books for children under the Puffin Books brand in 1939. At first these were non-fiction titles but these were soon followed by a fiction list of well-known authors. The demand was so great that Puffin Book Clubs were introduced in schools to encourage reading, and a children's magazine Puffin Post was established.[86] There is a tradition on the Icelandic island of Heimaey for the children to rescue young puffins, a fact recorded in Bruce McMillan's photo-illustrated children's book Nights of the Pufflings (1995). The fledglings emerge from the nest and try to make their way to the sea but sometimes get confused, perhaps by the street lighting, ending up by landing in the village. The children collect them and liberate them to the safety of the sea
Breeding range (blue), southern extent of summer range (black), and southern extent of winter range (red)
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