Strathcona Fiord is a fiord on the west central coast of
Ellesmere Island
Ellesmere Island ( iu, script=Latn, Umingmak Nuna, lit=land of muskoxen; french: île d'Ellesmere) is Canada's northernmost and third largest island, and the tenth largest in the world. It comprises an area of , slightly smaller than Great Bri ...
, the most northern island within the
Arctic Archipelago
The Arctic Archipelago, also known as the Canadian Arctic Archipelago, is an archipelago lying to the north of the Canadian continental mainland, excluding Greenland (an autonomous territory of Denmark).
Situated in the northern extremity of No ...
,
Nunavut
Nunavut ( , ; iu, ᓄᓇᕗᑦ , ; ) is the largest and northernmost territory of Canada. It was separated officially from the Northwest Territories on April 1, 1999, via the '' Nunavut Act'' and the '' Nunavut Land Claims Agreement Act'' ...
, Canada.
Geography
Strathcona Fiord is a southern tributary of Bay Fiord. The landscape in the region is fragile and spectacular. The steep hills forming the sides of the valley rise about above sea level. The striking arc of a
terminal moraine
A terminal moraine, also called end moraine, is a type of moraine that forms at the Glacier terminus, terminal (edge) of a glacier, marking its maximum advance. At this point, debris that has accumulated by plucking and abrasion, has been pushed ...
marks the limit of the last ice advance in the area. Taggart Lake running eastward of the moraine drains Upper and Lower Taggart lakes into the head of the fiord. The Prince of Wales Icefield lies on the eastern flank of this valley.
Human activity
Although currently there is no permanent settlement in the Strathcona Fiord area, stone tent rings and other archaeological features indicate past human habitation. Eureka, about to the northwest, is a weather station and staging point for scientific expeditions and for other visitors to Ellesmere Island and the Qikiqtaaluk Region. Grise Fiord is an
Inuit
Inuit (; iu, ᐃᓄᐃᑦ 'the people', singular: Inuk, , dual: Inuuk, ) are a group of culturally similar indigenous peoples inhabiting the Arctic and subarctic regions of Greenland, Labrador, Quebec, Nunavut, the Northwest Territories, ...
community, located about to the south, also on Ellesmere Island.
A parcel of land located south of the head of Strathcona Fiord is designated Inuit Owned Land. The area is sometimes visited by hunters from the nearest Inuit community, Grise Fiord.
Coal
A large portion of the Strathcona Fiord area lies within a coal license area, owned by Canadian Sovereign Coal Corporation, a subsidiary of Weststar Resources Corporation. The coal property is governed by three coal exploration licenses covering an area of . Coal deposits in the Strathcona Fiord area are ranked from lignite to sub-bituminous and have been estimated to comprise roughly 1 billion tonnes.
In January 2010, when the paleontological scientific community learned of Weststar's interest in exploring this area the Society of Vertebrate Paleontology issued a press release outlining the need to preserve the fossils in the area, Within four days the Nunavut Impact Review Board received over 70 letters of concern from paleontologists and the public alike.
Paleontology
The vicinity of Strathcona Fiord has yielded a fossil record of tremendous international scientific significance. These
fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...
s, including plant and animal remains, have provided a unique opportunity for understanding the effect of climatic change through the past 4 or 5 million years on the
Arctic
The Arctic ( or ) is a polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada ( Yukon, Northwest Territories, Nunavut), Danish Realm ( Greenland), Finland, Iceland ...
environment, and on its flora and fauna.
Pliocene fossils (3-5 million years old)
The only
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58vertebrate fossil locality known is the Beaver Pond site at Strathcona Fiord. The Beaver Pond site was first noted by John Fyles of the
Geological Survey of Canada
The Geological Survey of Canada (GSC; french: Commission géologique du Canada (CGC)) is a Canadian federal government agency responsible for performing geological surveys of the country, developing Canada's natural resources and protecting the e ...
in 1961. In 1988 he found the first
vertebrate
Vertebrates () comprise all animal taxon, taxa within the subphylum Vertebrata () (chordates with vertebral column, backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the ...
remains there. In 1992 vertebrate paleontologist,
Richard Harington
The Rev. Richard Harington (5 May 1800 – 13 December 1853) was an Oxford college head in the 19th century.
Barker was born in Hanover Square, Westminster and educated at Brasenose College, Oxford. A mathematician, he was Principal of Brasenose f ...
of the Canadian Museum of Nature, began ten summers of excavations at the site.
This fossil site includes the mummified remains of fossil plants, including trees such as an extinct
larch
Larches are deciduous conifers in the genus ''Larix'', of the family Pinaceae (subfamily Laricoideae). Growing from tall, they are native to much of the cooler temperate northern hemisphere, on lowlands in the north and high on mountains furt ...
(''Larix groenlandii'') and other trees indicative of a boreal forest.Matthews, Fyles 2000 Much of the wood preserved at the site has been gnawed by beavers and some of it is fire-blackened. This exceptional site also has yielded remains of pollen, insects, mollusks, fish (a
percid
The Percidae are a family of ray-finned fish, part of the order Perciformes, which are found in fresh and brackish waters of the Northern Hemisphere. The majority are Nearctic, but there are also Palearctic species. The family contains more than ...
), frogs and mammals such as an unusual rodent, a deerlet (''Boreameryx''), 3-toed horse, an extinct beaver (''Dipoides''), a rabbit ('' Hypolagus''), an unusual shrew (''Arctisorex polaris''), a primitive black bear (''Ursus abstrusus''), a badger (''Arctomeles''), and several other carnivores.
Paleoclimatic reconstruction suggests a mean annual temperature that was warmer than present day Ellesmere Island. The assemblage of Pliocene plant macrofossils (wood, leaves, cones and seeds) is typical of present-day boreal forest, as it includes
alder
Alders are trees comprising the genus ''Alnus'' in the birch family Betulaceae. The genus comprises about 35 species of monoecious trees and shrubs, a few reaching a large size, distributed throughout the north temperate zone with a few sp ...
(''Alnus''),
birch
A birch is a thin-leaved deciduous hardwood tree of the genus ''Betula'' (), in the family Betulaceae, which also includes alders, hazels, and hornbeams. It is closely related to the beech- oak family Fagaceae. The genus ''Betula'' contains 3 ...
larch
Larches are deciduous conifers in the genus ''Larix'', of the family Pinaceae (subfamily Laricoideae). Growing from tall, they are native to much of the cooler temperate northern hemisphere, on lowlands in the north and high on mountains furt ...
(''Larix''),
sweet gale
''Myrica gale'' is a species of flowering plant in the family Myricaceae, native to parts of Japan, North Korea, Russia, mainland Europe, the British Isles and parts of northern North America, in Canada and the United States. Common names include ...
(''Myrica gale''),
spruce
A spruce is a tree of the genus ''Picea'' (), a genus of about 35 species of coniferous evergreen trees in the family Pinaceae, found in the northern temperate and boreal ( taiga) regions of the Earth. ''Picea'' is the sole genus in the sub ...
(''Picea''),
pine
A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family (biology), family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanic ...
(''Pinus''), and lingonberry (''Vaccinium vitis-idaea''), as well as the southern boreal tree, the
white cedar White cedar may refer to several different trees:
* Bignoniaceae
** '' Tabebuia heterophylla'' - native to Caribbean islands and also cultivated as an ornamental tree
* Cupressaceae
Cupressaceae is a conifer family, the cypress family, with w ...
(''Thuja occidentalis'').
Eocene fossils (about 50 million years old)
The first High Arctic terrestrial fossil vertebrates were discovered in 1975, in the Strathcona Fiord by a team led by
Mary R. Dawson
Mary R. Dawson (February 27, 1931 – November 29, 2020) was a vertebrate paleontologist and curator emeritus at the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania.
Education and career
Dawson was raised in Michigan, received h ...
from the Carnegie Museum. These earliest finds include the fossil remains of an alligator, considered to be '' Allognathosuchus'', and also small arboreal mammals called ''plagiomenids''. Since then, field expeditions in Strathcona Fiord have yielded a much more complete picture of the
biodiversity
Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic ('' genetic variability''), species ('' species diversity''), and ecosystem ('' ecosystem diversity' ...
of the
Eocene
The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...
Arctic. Although, Eocene fossil vertebrates are known from other areas on Ellesmere Island (e.g., Stenkul Fiord), and
Axel Heiberg Island
Axel Heiberg Island ( iu, ᐅᒥᖕᒪᑦ ᓄᓈᑦ, ) is an uninhabited island in the Qikiqtaaluk Region, Nunavut, Canada. Located in the Arctic Ocean, it is the 32nd largest island in the world and Canada's seventh largest island. Accordin ...
, Strathcona Fiord has yielded the richest vertebrate fossil record.
The fossil vertebrate record of the Eocene Arctic includes giant tortoises, varanid lizards, and boid snakes. Mammal fossils are extremely diverse, including the rhino-like
brontotheres
Brontotheriidae is a family of extinct mammals belonging to the order Perissodactyla, the order that includes horses, rhinoceroses, and tapirs. Superficially, they looked rather like rhinos, although they were actually more closely related to h ...
tapir
Tapirs ( ) are large, herbivorous mammals belonging to the family Tapiridae. They are similar in shape to a pig, with a short, prehensile nose trunk. Tapirs inhabit jungle and forest regions of South and Central America, with one species inh ...
like relative (''Thuliadanta''), an early horse (''
Hyracotherium
''Hyracotherium'' ( ; " hyrax-like beast") is an extinct genus of very small (about 60 cm in length) perissodactyl ungulates that was found in the London Clay formation. This small, fox-sized animal was once considered to be the earliest ...
Miacis
''Miacis'' is a genus of extinct carnivorous mammals that appeared in the late Paleocene and continued through the Eocene. The genus ''Miacis'' is not monophyletic but a diverse collection of species that belong to the stemgroup within the ...
''), meat-eating creodonts (e.g. ''Paaeonictis''), a
mesonychid
Mesonychia ("middle claws") is an extinct taxon of small- to large-sized carnivorous ungulates related to artiodactyls. Mesonychids first appeared in the early Paleocene, went into a sharp decline at the end of the Eocene, and died out entirel ...
leptictid
Leptictida (''leptos iktis'' "small/slender weasel") is a possibly paraphyletic extinct order of eutherian mammals. Their classification is contentious: according to cladistic studies, they may be (distantly) related to Euarchontoglires (roden ...
and at least five rodents (including '' Paramys'' and ''Microparamys''). There are over 40 fossil vertebrate sites in the Strathcona Fiord region.
There are numerous Eocene plant fossil sites, including
shale
Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especia ...
units that are rich with leaves as compression fossils.Basinger, Greenwood, Sweda 1994McIver, Basinger 1999 Very notable are the petrified tree stumps, some of which are preserved in their original growth position. The trees show wide
growth rings
Dendrochronology (or tree-ring dating) is the scientific method of dating tree rings (also called growth rings) to the exact year they were formed. As well as dating them, this can give data for dendroclimatology, the study of climate and atmo ...
indicating favorable growth conditions. The fossil flora indicates the presence of rich floodplain forests dominated by dawn redwood (''
Metasequoia glyptostroboides
''Metasequoia glyptostroboides'', the dawn redwood, is a fast-growing, endangered deciduous conifer. It is the sole living species of the genus ''Metasequoia'', one of three genera in the subfamily Sequoioideae of the family Cupressaceae. It now ...
''), together with
ginkgo
''Ginkgo'' is a genus of non-flowering seed plants. The scientific name is also used as the English name. The order to which it belongs, Ginkgoales, first appeared in the Permian, 270 million years ago, and is now the only living genus withi ...
(''Ginkgo adiantoides''), walnut family (''
Juglans
Walnut trees are any species of tree in the plant genus ''Juglans'', the type genus of the family Juglandaceae, the seeds of which are referred to as walnuts. All species are deciduous trees, tall, with pinnate leaves , with 5–25 leaflets ...
'' and other
Juglandaceae
The Juglandaceae are a plant family known as the walnut family. They are trees, or sometimes shrubs, in the order Fagales. Members of this family are native to the Americas, Eurasia, and Southeast Asia.
The nine or ten genera in the family have ...
Betulaceae
Betulaceae, the birch family, includes six genera of deciduous nut-bearing trees and shrubs, including the birches, alders, hazels, hornbeams, hazel-hornbeam, and hop-hornbeams numbering a total of 167 species. They are mostly natives of ...
), and katsura ('' Cercidiphyllum''). Analysis of nearby fossil leaf sites from central Ellesmere Island of the same age indicate that these forests grew under very high rainfall, and can be considered to have represented a polar rainforest.Greenwood, Basinger, Smith 2010
This lush Eocene ecosystem thrived under a polar light regime. Like today, the region would have seen 24-hour sun in the summer and 24-hour darkness in the winter as it was positioned at almost the same latitude in the Eocene as it is today. Despite an
early Eocene
In the geologic timescale the Ypresian is the oldest age (geology), age or lowest stage (stratigraphy), stratigraphic stage of the Eocene. It spans the time between , is preceded by the Thanetian Age (part of the Paleocene) and is followed by th ...
climate with generally mild frost-free temperatures, the polar light regime likely forced these plants to be deciduous.