Champlain Sea fossils

These images are a selection of marine fossils from deposits of the Champlain Sea, an ocean bay which filled most of the Ottawa-St.Lawrence-Lake Camplain basin at the end of the last continental glaciation, about 8000-11000 years ago.

map of the Champlain Sea showing localities for fossil whales. Modified after Harington.

Clams

These clams were collected from unconsolidated sand south of the city of Ottawa, Ontario. Some were articulated (both valves) when originally collected. Both these species are still found today in cool North Atlantic and Arctic Ocean waters and are exclusively marine.

Hiatella arctica

Hiatella arctica

Macoma balthica

Macoma balthica

Fish

Many species of fish are known from Champlain Sea deposits. A good description of the assemblage and citations to earlier work can be found in McAllister, et al., from which the following table is extracted:

Coregonus artedii Le Sueur -- lake cisco
Salvelinus namaycush (Walbaum) -- lake charr
Mallotus villosus (Mueller) -- capelin
Osmerus mordax (Mitchell) -- rainbow smelt
Catostomus catostomus (Forster) -- longnose sucker
Gadus morhua Linnaeus -- Atlantic cod
Microgadus tomcod (Walbaum) -- Atlantic tomcod
Cottus ricei (Nelson) -- spoonhead sculpin
Myxocephalus thompsoni (Girard) -- deepwater sculpin
Cyclopterus lumpus Linnaeus -- lumpfish
Gasterosteus aculeatus Linnaeus -- threespine stickleback

This fauna has greatest similarity to the southern coast of Labrador.

This specimen is from the Leda Clay at Green's Creek, east of Ottawa, Ontario, and is in a carbonate-cemented concretion from green, laminated, unconsolidated clay. Some of the original bedding is slightly visible on the surface of the concretion.

Mallotus villosus (Mueller)

The capelin. According to McAllister et al., this species is found in "cold, saline northern seas of the North Atlantic, North Pacific, and Arctic oceans. On the Atlantic coast of North America, they extend from Thule, Greenland, south to the Gulf of Maine."

Marine mammals

Both seals and whales are known from deposits of the Champlain Sea. The fossils include several articulated skeletons. Harington has recently summarized the available data and has references to much more information. The following species are known:

Seals

Phoca groenlandica -- harp seal
Eringnathus barbatus -- bearded seal
Phoca hispida -- ringed seal

These all breed on sea ice.

Phoca vitulina -- harbour seal

Whales

"Beluga vermontana" Thompson -- skull of a beluga.

From page 568 of Dana, 1875. Specimen is from, "on the borders of Lake Champlain, sixty feet above its level, or 150 feet above that of the ocean" (Dana, 1875, p.552) This is locality 3 on the map above. According to Harington, "most of a skeleton is preserved in the state museum, Montpelier, Vermont" (p.228). The specimen was originally described by Thompson (1850) and has been subsequently assigned to Delphinapterus leucas, the same species as the modern beluga.

Delphinapterus leucas -- beluga or white whale
Pocoena phocoena -- harbour porpoise
Megaptera novaeangliae -- humback whale
Balaeonoptera physalus -- finback whale
Balaena mysticetus -- bowhead whale

A few other disarticulated bones are known from Michigan, but they may be transported by humans, do not occur with in situ marine fossils (e.g., clams), and are much younger than Lake Champlain occurrences. For more details, see Harington.

References

Dana, James D., 1875. Manual of Geology: Treating the principles of the science with special reference to American geological history. Ivison, Blakeman, Taylor, and Co.: New York, p.1-828.

Harington, C.R. Marine Mammals of the Champlain Sea, and the problem of whales in Michigan. IN: Gadd, N.R. (ed.), The Late Quaternary Development of the Champlain Sea Basin. Geological Association of Canada, Special Paper 35, p.225-240.

McAllister, D.E.; Harington, C.R.; Cumba, S.L.; and Renaud, C.B. Paleoenvironmental and biogeographic analyses of fossil fishes in the peri-Champlain Sea deposits in Eastern Canada. IN: Gadd, N.R. (ed.), The Late Quaternary Development of the Champlain Sea Basin. Geological Association of Canada, Special Paper 35, p.241-258.

Thompson, Z., 1850. An account of some fossil bones found in Vermont, in making excavations for the Rutland and Burlington Railroad. American Journal of Science, Series 2, v.9, p.256-263.

Andrew MacRae macrae@geo.ucalgary.ca