Friday, 29 December 2006
NORTH AMERICAN BROWN BEAR
At age five, female (sows) grizzlies begin mating and bearing young, usually two cubs every other year. The cubs arrive over the winter and feast on their mother's milk all snuggled inside a wintery den.
The great ancestors of the North American brown bear are the Ursavus, a bear-dog the size of a raccoon who lived more than 20 million years ago. Taking a look at this beauty, it seems an implausible lineage.
Thursday, 28 December 2006
Saturday, 23 December 2006
Monday, 11 December 2006
SHELTER POINT FOSSIL CRAB SITE
Shelter Point on northern Vancouver Island is a lovely beach site where clastic strata are exposed in the intertidal platform of Oyster Bay.
The site is located just off the Island Highway, about 10 km south of downtown Campbell River and 4 km farther south along the lower Oyster River. Haggart et al. presented an abstract on this locality at the 12th British Columbia Paleontological Symposium, 2018, Courtenay, abstracts; 2018 p. 28-30. I'll pop a link below if you'd like to give it a read.
Shelter Point has been collected since the 1970s. No pre-glacial strata were recognized in this area by Muller and Jeletzky (1970). Richards (1975) described an abundant fauna in the beds at Shelter Point, approximately 2 km north of the Oyster Bay exposures, including the crab Longusorbis and associated ammonites and inoceramid bivalves, and he assigned these beds to the Spray Formation of the Nanaimo Group. This information, combined with the very low dip of the Oyster Bay strata and their general lithological similarity with the coarse clastic strata found commonly in the Nanaimo Group, suggested a Late Cretaceous (Campanian) age of the Oyster Bay strata.
Beginning in the 1980s, fossil collectors from the Vancouver Island Palaeontological Society began amassing significant collections of fossils from the strata of southern Oyster Bay that are found several hundred metres southeast of the local road called Appian Way, thus providing the informal moniker Appian Way Beds for these localized exposures.
While these collections included a great diversity of gastropod, bivalve, nautiloid, scaphopod, echinoderm, and coral specimens, as well as impressive collections of plant materials, much previously undescribed, no taxa found commonly in Campanian strata of the Nanaimo Group were noted in these collections; particularly lacking were ammonites and inoceramid bivalves. For this reason, the hypothesis began to emerge that the Appian Way Beds of Oyster Bay were of younger, post-Cretaceous, age than thought previously.
Just how young, however, has been a source of some controversy, with different parties continuing to favour the traditional Campanian age — based on lithostratigraphy — others a Paleocene age, and still others an Eocene age — based on plant macrofossils.
Fossil Collecting at Shelter Point:
|Fossil Collecting at Shelter Point|
Industrious collectors unwilling to wait for the tide have employed rubber boots to wade through knee-deep water — rubber boots are highly recommended in any case — and even headlamps to capitalize on low tides during the night. Bring eye protection and sunscreen to safely enjoy this lovely family trip.
The fossils, mainly the crab, Longusorbis and the straight ammonite Baculites, occur only in the gritty concretions that weather out of the shale. You'll need a rock hammer to see the lovelies preserved inside. Best to hold the concretion in your hand and give it one good tap. Aside from the fossils, check out the local tide pools and sea life in the area. Those less interested in the fossils can look for seals and playful otters basking on the beaches.
Haggart, J. et al. 58 million and 25 years in the making: stratigraphy, fauna, age, and correlation of the Paleocene/Eocene sedimentary strata at Oyster Bay and adjacent areas, southeast Vancouver Island, British Columbia; https://geoscan.nrcan.gc.ca/starweb/geoscan/servlet.starweb?path=geoscan/fulle.web&search1=R=308471