Long before grizzly bears and mountain lions roamed the wild in northeastern British Columbia, carnivores that were best avoided in the area included the colossal relatives of modern crocodiles. The researchers concluded long after they discovered nail marks created about 97 million years ago by scary reptiles, which used their fingernails to pull the muddy bottom of a shallow waterway. The recesses were later filled with mud, which became sandstone over the centuries, leaving characteristic motifs discovered on exposed rock near a highway that runs along the Sukunka River Valley north of Tumbler Ridge, BC. “The cohesiveness of the mud was good for preserving crocodile tracks,” said Guy Plint, a geologist at the University of Western Ontario. “Even the impressions of the scales on their feet can be recognized.” The marks are similar to those left by crocodiles today, only they are larger. Measurements by Dr. Plint and his colleagues show that the prehistoric yolks were 9 to 12 meters long and weighed about five tons. The team’s results were published last month in the journal Historical Biology. Crocodile signs were found near dinosaur footprints, suggesting that the area alternated between aquatic and coastal habitats. At the time, the area was a low-lying delta plain, where giant crocodiles may have been the area’s top predators, hiding in lakes and rivers where they could grab careless dinosaurs and drag them underwater to death, he said. Dr. He added that while dinosaurs tend to attract more public attention, the crocodile reptiles of the period are fascinating in part because they managed to overcome the important extinction event 66 million years ago that wiped out dinosaurs and most other species living in at that time. “Yolks are clearly the great survivors,” said Dr. Plint. We have a weekly newsletter for Western Canada compiled by the heads of our offices in BC and Alberta, providing a comprehensive package of news you need to know about the area and its position on issues facing Canada. Register today.
