Divers or Loons
Common Loon or Great Northern Diver Gavia immer
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Aves Subclass: Neornithes Infraclass: Neoaves Order: Gaviiformes Wetmore & Miller, 1926 Family: Gaviidae J.A. Allen, 1897 Genus: Gavia Forster, 1788
Species
Gavia adamsii Gavia arctica Gavia immer Gavia pacifica Gavia stellata

The loons (e. The Great Northern Diver, known in North America as the Common Loon ( Gavia immer) is a large member of the Loon, or diver Family Chordates ( Phylum Chordata) are a group of Animals that includes the Vertebrates together with several closely related Invertebrates Birds ( class Aves) are bipedal endothermic ( Warm-blooded) Vertebrate animals that lay eggs. Modern birds (subclass Neornithes) are the members of class Aves that have survived into recent times and have coexisted with Humans Modern birds are Neognaths ( Neognathae) are Birds within the Subclass Neornithes of the class Aves. Frank Alexander Wetmore ( June 18, 1886 &ndash December 7, 1978) was an American Ornithologist and avian Paleontologist Year 1926 ( MCMXXVI) was a Common year starting on Friday (link will display the full calendar of the Gregorian calendar. Joel Asaph Allen ( July 19, 1838 - August 29, 1921) was an American Zoologist and Ornithologist. Year 1897 ( MDCCCXCVII) was a Common year starting on Friday (link will display the full calendar of the Gregorian Calendar (or a Common Johann Reinhold Forster ( October 22, 1729 &ndash December 9, 1798) was a German naturalist of partial Scottish Year 1788 ( MDCCLXXXVIII) was a Leap year starting on Tuesday (link will display the full calendar of the Gregorian calendar (or a Leap The White-billed Diver, known in North America as Yellow-billed Loon ( Gavia adamsii) is the largest member of the Loon or diver family Black-throated Diver ( Gavia arctica) known in North America as Arctic Loon, is a medium-sized member of the Loon or diver family The Great Northern Diver, known in North America as the Common Loon ( Gavia immer) is a large member of the Loon, or diver Family The Pacific Diver ( Gavia pacifica) known in North America as the Pacific Loon, is a medium-sized member of the Loon, or diver family The Red-throated Diver ( Gavia stellata) known in North America as the Red-throated Loon, is the smallest and most widely distributed member of the g. North America) or divers (e. g. UK/Ireland) are a group of aquatic birds found in many parts of North America and northern Europe. A loon is the size of a large duck or small goose, which it somewhat resembles in shape when swimming. For duck as a food see Duck (food; for other meanings see Duck (disambiguation.

The plumage is largely black-and-white, with grey on the head and neck in some species, and a white belly, and all species have a spear-shaped bill. Feathers are one of the epidermal growths that form the distinctive outer covering or Plumage, on Birds They are considered the most complex integumentary structures All living species of loons are members of one genus (Gavia^[1] in a family (Gaviidae), and order (Gaviiformes) all of their own. A genus (plural genera from Γένος Latin genus "descent family type gender" is a low-level Taxonomic In Biological classification, family ( Latin This article is about the taxonomic rank for the sequence of species in a taxonomic list see Taxonomic order In scientific classification used

The European name "diver" comes from the bird's habit of catching fish by swimming calmly along the surface and then abruptly plunging into the water. The North American name loon comes from the bird's haunting, yodeling cry.

Contents 1 Ecology 1.1 Diet 1.2 Reproduction 2 Systematics and evolution 2.1 Relationships and evolution 3 Loons in popular culture 4 Footnotes 5 References 6 External links

Ecology

Loons are excellent swimmers, using their feet to propel themselves above and under water and their wings for assistance. Because their feet are far back on the body, loons are poorly adapted to moving on land. They usually avoid going onto land, except when nesting.

All loons are decent fliers, though the larger species have some difficulty taking off and thus must swim into the wind to pick up enough velocity to get airborne. Only the Red-throated Diver can take off from land. The Red-throated Diver ( Gavia stellata) known in North America as the Red-throated Loon, is the smallest and most widely distributed member of the Once airborne, their considerable stamina allows them to migrate long distances southwards in winter, where they reside in coastal waters. Loons can live as long as 30 years.

Diet

Loons find their prey by sight. They eat fish, amphibians, and crustaceans. Prehistoric amphibian Amphibians (class Amphibia such as Frogs Toads Salamanders Newts Gymnophiona, Sirens and Specifically, they eat crayfish, frogs, snails, salamanders and leeches. They prefer clear lakes because they can see their prey more easily through the water. The loon uses its pointy bill to stab or grasp prey. They eat vertebrate prey headfirst to facilitate swallowing, and swallow all their prey whole.

To help digestion, loons swallow small pebbles from the bottoms of lakes. Similar to grit eaten by chickens, these gastroliths may assist the loon's gizzard in crushing the hard parts of the loon's food such as the exoskeletons of crustaceans and the bones of frogs and salamanders. The chicken ( Gallus gallus, sometimes G gallus domesticus) is a domesticated Fowl which is traditionally believed to have descended from Gastroliths (' Stomach stones' or ' Gizzard stones' are rocks, which are or have been held inside the digestive tract of an animal The gizzard, also referred to as the ventriculus, gastric mill, and gigerium, is an organ in the digestive tract found in Birds Reptiles An exoskeleton is an external Skeleton that supports and protects an animal's body in contrast to the internal Endoskeleton of for example a Human. The gastroliths may also be involved in stomach cleaning as an aid to regurgitation of indigestible food parts.

Loons may inadvertently ingest small lead pellets, released by anglers and hunters, which will slowly lead to the loon's death by lead poisoning. Jurisdictions that have banned the use of lead shot and sinkers include Maine, New Hampshire, Vermont, some areas of Massachusetts, Yellowstone National Park, Great Britain, Canada, and Denmark. The State of Maine ( is a state in the New England region of the northeastern United States of America, bordering the Atlantic Ocean New Hampshire ( is a state in the New England region of the northeastern United States of America. Vermont ( is a state in the New England region of the northeastern United States of America. The Commonwealth of Massachusetts ( is a state located in the New England region of the northeastern United States. See also Kingdom of Great Britain Great Britain (Breatainn Mhòr Prydain Fawr Breten Veur Graet Breetain is the larger of the two main islands Country to "Dominion of Canada" or "Canadian Federation" or anything else please read the Talk Page The Kingdom of Denmark ( ˈd̥ænmɑɡ̊ (archaic ˈd̥anmɑːɡ̊ commonly known as Denmark, is a country in the Scandinavian region of northern Europe ^[2]

Reproduction

During the summer, loons nest on fresh water lakes and/or large ponds. The Great Northern Diver, known in North America as the Common Loon ( Gavia immer) is a large member of the Loon, or diver Family Smaller bodies of water (up to 0. 5 km²) will usually only have one pair. Square Kilometre ( US spelling square kilometer) symbol km2, is a decimal multiple of the SI unit of Larger lakes may have more than one pair, with each pair occupying a bay or section of the lake.

Loons build their nests close to the water, preferring sites that are completely surrounded by water. They may use the same site from year to year. Loons will use a variety of materials found nearby to build their nests including pine tree needles, leaves, grass, moss, and sometimes clumps of mud. Both the male and female help with nest building and incubation, which usually lasts 26-31 days. If the eggs are lost, the pair may re-nest, often in the same general location.

Usually one or two eggs are laid in June. Loon chicks are precocial, able to swim right away, but are often seen riding on their parents' back. In Biology, the term precocial refers to species in which the young are relatively mature and mobile from the moment of birth or hatching This behavior allows the chicks to rest, conserve heat, and avoid predators such as large carnivorous fish, snapping turtles, gulls, eagles, and crows. After a day or two, chicks cease returning to the nest but remain in their parent's company.

Chicks remain with and are fed exclusively by their parents for about eight weeks. After eight weeks, chicks will begin to dive for some of their own food. By 11 or 12 weeks of age, chicks are able to gather almost all of their own food and may be able to fly.

A pair may mate for life, although banding studies have shown that loons will sometimes switch mates after a failed nesting attempt and even between nesting attempts in the same season. ^[3] Male loons appear more faithful to breeding territories than to mates. ^[4]

Systematics and evolution

All living species are classed in the genus Gavia. Black-throated Diver ( Gavia arctica) known in North America as Arctic Loon, is a medium-sized member of the Loon or diver family

• Red-throated Diver or Red-throated Loon, Gavia stellata. The Red-throated Diver ( Gavia stellata) known in North America as the Red-throated Loon, is the smallest and most widely distributed member of the
• Black-throated Diver or Arctic Loon, Gavia arctica. Black-throated Diver ( Gavia arctica) known in North America as Arctic Loon, is a medium-sized member of the Loon or diver family
• Pacific Diver or Pacific Loon, Gavia pacifica - formerly included in G. The Pacific Diver ( Gavia pacifica) known in North America as the Pacific Loon, is a medium-sized member of the Loon, or diver family arctica
• Great Northern Diver or Common Loon, Gavia immer. The Great Northern Diver, known in North America as the Common Loon ( Gavia immer) is a large member of the Loon, or diver Family
• White-billed Diver or Yellow-billed Loon, Gavia adamsii

Relationships and evolution

The loons were formerly often considered to be the most ancient of the northern hemisphere bird families; this idea grew basically out of the perceived similarity of shape and (probably) habits between loons and the entirely unrelated extinct Cretaceous order Hesperornithiformes. The White-billed Diver, known in North America as Yellow-billed Loon ( Gavia adamsii) is the largest member of the Loon or diver family The Cretaceous (kriːˈteɪʃəs, usually abbreviated 'K' for its German translation "Kreide" is a geologic period and system, reaching from the end of Hesperornithes is an extinct and highly specialized Clade of Cretaceous toothed Birds Hesperornithine birds apparently limited to former aquatic habitats However, the two groups are merely the product of convergent evolution and adapted in a similar way to a similar ecological niche. Convergent evolution describes the acquisition of the same biological trait in unrelated lineages In Ecology, a niche (pronounced nich nēsh or nish A shorthand definition of niche is how an organism makes a living ^[5]

More recently, it has become clear that the Anseriformes (waterfowl) and the Galliformes are the most ancient groups of modern birds, while loons belong to a more modern radiation. The order Anseriformes contains about 150 living Species of Birds in three extant families the Anhimidae (the screamers Anseranatidae Galliformes are an order of Birds containing turkeys, Grouse, Chickens Quails and Pheasants More than 250 What is also generally accepted as a fact is that loons and grebes are not closely related at all, but rather one of the most stunning examples of convergence in the known birds. Grebes are members of the Podicipediformes order, a widely distributed order of freshwater diving birds some of which visit the sea when migrating The Sibley-Ahlquist taxonomy still allied the loons with the grebes in its paraphyletic "Ciconiiformes", and it is almost certain that the relationships of loons lie with some of the orders united therein. The Sibley-Ahlquist taxonomy is a radical bird Taxonomy proposed by Charles Sibley and Jon Edward Ahlquist. In Phylogenetics, a group of organisms is said to be paraphyletic if the group contains its most recent common ancestor but does not contain all Alternatively, loons have tentatively been considered to share a rather close relationship with waders, penguins or procellariiform seabirds. Waders, called shorebirds in North America (where "wader" is used to refer to long-legged wading Birds such as Storks and Penguins ( order Sphenisciformes, family Spheniscidae) are a group of aquatic, flightless Birds living almost Procellariiformes is an order of Seabirds that comprises four families: the Albatrosses procellariids, Storm-petrels and Diving ^[6]

The conflicting molecular data is not much resolved by the fossil record. FOSSIL is a standard protocol for allowing serial communication for Telecommunications programs under the DOS Operating system. Modern loons are only known with certainty since the Eocene, but by that time almost all modern bird orders are known or strongly suspected to have existed anyway. The Eocene epoch (558 ± 02 - 339 ± 01 Ma) is a major division of the Geologic timescale and the second epoch of the Palaeogene period in The Late Eocene to Early Miocene genus Colymboides was widespread in Western and Central Europe; it is usually placed in the Gaviidae already, but may actually be more primitive; it is quite distinct from modern loons and could well be paraphyletic. The Miocene is a geological epoch of the Neogene period and extends from about 23 From the genus Gavia, about a dozen fossil species have been discovered to date, which are known from the Early Miocene onwards and had a more southerly distribution, like today's California, Florida and Italy:

• Gavia egeriana Švec, 1982 (Early Miocene of Czechoslovakia -? Late Miocene of E USA)
• Gavia schultzi Mlíkovský, 1998 (Middle Miocene of Sankt Margarethen, Austria)
• Gavia sp. California ( is a US state on the West Coast of the United States, along the Pacific Ocean. Florida ( is a state located in the southeastern region of the United States, bordering Alabama to the northwest and Georgia to the Italy (Italia officially the Italian Republic, (Repubblica Italiana is located on the Italian Peninsula in Southern Europe, and on the two largest (Calvert? Middle Miocene or Maryland, USA)^[7]
• Gavia spp. (Middle Miocene of Steinheim, Germany) - 3 species^[8]
• Gavia brodkorbi (Late Miocene of Orange County, USA)
• Gavia moldavica Kessler, 1984 (Late Miocene of Chişinău, Moldova)
• Gavia paradoxa Umanska, 1981 (Late Miocene of Čebotarevka, Ukraine)
• Gavia concinna Wetmore, 1940 (Late Miocene/Early Pliocene -? Late Pliocene of W and SE USA)^[9]
• Gavia fortis Olson & Rasmussen, 2001 (Yorktown Early Pliocene of Lee Creek Mine, South Carolina, USA)
• Gavia sp. Frank Alexander Wetmore ( June 18, 1886 &ndash December 7, 1978) was an American Ornithologist and avian Paleontologist (Early Pliocene of Kerč Peninsula, Ukraine)^[8]
• Gavia spp. (Yorktown Early Pliocene of Lee Creek Mine, South Carolina, USA) - 2 species
• Gavia howardae Brodkorb, 1953 (Middle Pliocene of San Diego, California, USA)^[10]
• Gavia cf. Pierce Brodkorb (born September 29, 1908 in Chicago, Illinois, died July 18, 1992 in Gainesville Florida) concinna (Middle Pliocene of San Diego, California, USA)^[11]
• Gavia palaeodytes Wetmore, 1943 (Middle Pliocene of Pierce, Florida, USA)^[12]
• Gavia sp. (Early Pleistocene of Kairy, Ukraine)^[8]
• Gavia cf. immer (Pleistocene of California and Florida, USA) - possibly a G. immer paleosubspecies^[13]

"Gavia" portisi from the Late Pliocene of Orciano Pisano (Italy) is known from a cervical vertebra that may or may not have been from a loon. A chronospecies is a Species which changes physically morphologically, genetically, and/or behaviorally over time on an evolutionary scale such The Pliocene epoch (spelled Pleiocene in some older texts is the period in the Geologic timescale that extends Orciano Pisano is a Comune (municipality in the Province of Pisa in the Italian region Tuscany, located about 70 km southwest Italy (Italia officially the Italian Republic, (Repubblica Italiana is located on the Italian Peninsula in Southern Europe, and on the two largest In Vertebrates cervical vertebrae (singular vertebra) are those vertebrae immediately behind (posterior to the Skull. If so, it was from a bird slightly smaller than Common Loon. The Great Northern Diver, known in North America as the Common Loon ( Gavia immer) is a large member of the Loon, or diver Family Older authors were quite sure the bone was indeed from a Gavia and even considered G. concinna a possibly junior synonym of it. In Scientific nomenclature, synonyms are different Scientific names used for a single Taxon. This is now regarded as rather unlikely for reasons of biogeography. Interestingly, an Early Pliocene loon skull form Empoli (Italy) was referred to G. In the Geologic time scale, the Zanclean (also known as Tabianian, Dacian) is the Age which makes up the Early Pliocene Empoli is a town in Tuscany, Italy, about 30 km southwest of Florence. concinna. The vertebra may now be lost, making "G. " portisi a nomen dubium. In zoological nomenclature, a nomen dubium ( Latin for "doubtful name" plural nomina dubia) is a scientific name that is ^[14]

In addition, there are some much older forms that are sometimes assigned to the Gaviiformes. From the Late Cretaceous, the genera Lonchodytes (Lance Formation, Wyoming) and Neogaeornis (Quinriquina Formation, Chile) have been described; the latter might have been a primitive loon, but possibly a hesperornithiform, and both have sometimes been allied with the orders which are considered related to loons. Late Cretaceous (100mya - 65mya refers to the second half of the Cretaceous Period, named after the famous white Chalk cliffs of southern England Lonchodytes is a Late Cretaceous Genus of Aquatic Bird, which lived along the shores of the Western Interior Seaway The Lance (Creek Formation is a division of Late Cretaceous rocks in the western United States Neogaeornis is a controversial prehistoric Genus of diving Bird. Chile, officially the Republic of Chile ( Spanish:) is a country in South America occupying a long and narrow Coastal strip wedged between the Hesperornithes is an extinct and highly specialized Clade of Cretaceous toothed Birds Hesperornithine birds apparently limited to former aquatic habitats Doubtfully valid and surrounced by considerable dispute^[15] is the supposed Late Cretaceous loon Polarornis (Seymour Island, Antarctica). Polarornis is a controversial (see Mayr 2002 Genus of prehistoric Bird. For Baltra Island, also called South Seymour Island, in the Galápagos Islands group see Baltra Island. Eupterornis from the Paleocene of France has some features reminiscent of loons, but others seem more similar to Charadriiformes such as gulls (Laridae). The Paleocene or Palaeocene, "early dawn of the recent" is a geologic epoch that lasted from 65 Charadriiformes is a diverse order of small to medium-large Birds It includes about 350 Species and has members in all parts of the world Gulls (often informally Seagulls) are birds in the family Laridae A piece of a carpometacarpus supposedly from Oligocene rocks near Lusk, Wyoming was described as Gaviella pusilla, but this also shows some similarities to the plotopterids. The Oligocene is a geologic epoch of the Paleogene period and extends from about 33 Lusk may also refer to a rural town in the part of County Dublin now overseen by Fingal County Council, Ireland. Plotopteridae is the name of an Extinct family of flightless Seabirds from the order Pelecaniformes. ^[16] Parascaniornis, sometimes allied to the loons, has more recently determined to be a junior synonym of the hesperornithiform Baptornis. In Scientific nomenclature, synonyms are different Scientific names used for a single Taxon. Baptornis ("diving bird" is an extinct Genus of flightless aquatic Bird from the Late Cretaceous, some 87-80 million

Loons in popular culture

The Common Loon is the provincial bird of Ontario and is depicted on the Canadian one-dollar coin, which has come to be known affectionately as the "loonie". Ontario (ɒnˈtɛrioʊ is a province located in the central part of Canada, the largest by population and second largest after Quebec Loonie is the name Canadians gave the gold-coloured bronze-plated one-dollar Coin shortly after its introduction in 1987. ^[17] It is also the official state bird of Minnesota,^[18] and Mercer, Wisconsin promotes itself as the "Loon Capital of the World". Minnesota ( Native Americans demonstrated the name to early settlers Mercer is a town in southern Iron County, Wisconsin, United States. ^[19] Loons are mentioned several times in the film On Golden Pond. On Golden Pond is a 1981 American Drama film directed by Mark Rydell.

Footnotes

References

• Brodkorb, Pierce (1953): A Review of the Pliocene Loons. Pierce Brodkorb (born September 29, 1908 in Chicago, Illinois, died July 18, 1992 in Gainesville Florida) Condor 55(4): 211-214. This article is about the journal The Condor for information about the bird from which it takes it name see Condor. PDF fulltext DjVu fulltext
• Heinrichs, Ann (2003): Minnesota. Compass Point Books. ISBN 0756503159
• Mayr (2004): A partial skeleton of a new fossil loon (Aves, Gaviiformes) from the early Oligocene of Germany with preserved stomach content. J. Ornithol. 145: 281-286 doi:10.1007/s10336-004-0050-9 PDF fulltext
• Minnesota Pollution Control Agency (2007): Let's Get the Lead Out! Non-lead alternatives for fishing tackle. The Journal of Ornithology (formerly Journal für Ornithologie) is a scientific journal published by the Deutsche Ornithologen-Gesellschaft. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. Version of June, 2007. Retrieved 2007-JUL-23.
• Mlíkovský, Jirí (2002): Cenozoic Birds of the World, Part 1: Europe. Ninox Press, Prague. ISBN 80-901105-3-8 PDF fulltext
• Montana Fish, Wildlife & Parks (Montana FW&P) (2007): Animal Field Guide: Common Loon. Retrieved 2007-MAY-12.
• Moran, Mark; Sceurman, Mark; Godfrey, Linda S. & Hendricks, Richard D. (2005): Weird Wisconsin: Your Travel Guide to Wisconsin's Local Legends and Best Kept Secrets. Sterling Publishing. ISBN 0760759448
• Olson, Storrs L. (1985): Section X. Storrs Lovejoy Olson (born April 3, 1944 in Chicago, Illinois) is an American biologist and ornithologist from the Smithsonian Institution I. Gaviiformes. In: Farner, D. S. ; King, J. R. & Parkes, Kenneth C. (eds. ): Avian Biology 8: 202-214. Academic Press, New York.
• Stewart, Barry D. (2004): Across The Land: A Canadian Journey Of Discovery. Trafford Publishing. ISBN 1412022762
• Stolpe, M. (1935): Colymbus, Hesperornis, Podiceps:, ein Vergleich ihrer hinteren Extremität. J. Ornithol. 80(1): 161-247. The Journal of Ornithology (formerly Journal für Ornithologie) is a scientific journal published by the Deutsche Ornithologen-Gesellschaft. [Article in German] doi:10.1007/BF01908745
• Wetmore, Alexander (1941): An Unknown Loon from the Miocene Fossil Beds of Maryland. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document. Frank Alexander Wetmore ( June 18, 1886 &ndash December 7, 1978) was an American Ornithologist and avian Paleontologist Auk 58(4): 567. The Auk is a quarterly Journal and the official publication of the American Ornithologists' Union, having been continuously published by that body since PDF fulltext DjVu fulltext
• United States Fish and Wildlife Service (USFWS) (2005): Common Loons at Seney NWR, June 2005. PDF fulltext
• Wings, Oliver (2007): A review of gastrolith function with implications for fossil vertebrates and a revised classification. Acta Palaeontologica Polonica 52: 1-16 PDF fulltext

External links

• Video of nesting loons. Video captures the laying and hatching of two eggs on Lake George in Minnesota. History Lake George was formed about 20000 years ago when glacial ice receded ^[1]
• Tree of Life Gaviidae
• Loon sounds
• Loon videos on the Internet Bird Collection
• Loon Preservation Committee
• Diving Birds of North America, by Paul Johnsgard

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