Wed. Nov 29th, 2023
Dinosaurs in the parks!

Today’s post comes from Christian Therrien, former Senior Assistant Ecologist for the North West Zone.

Most agree that all dinosaurs became extinct 66 million years ago.

However, looking at the species found in the parks reveals that some dinosaurs have indeed persisted and can be seen today.

From the snapping turtle to the silver lamprey, remnants of this forgotten era stand out today in Ontario parks.

However, of all the dinosaurs in our parks, the most impressive is Lake Sturgeon.

A juvenile sturgeon captured in Lake SuperiorA juvenile sturgeon captured in Lake Superior

Despite surviving four mass extinction events throughout history and asteroids, climate change and global volcanic eruptions that wiped out most species on Earth, the sturgeon has not been invulnerable to man.

They are now considered an endangered species in Ontario.

A remnant from 400 million years ago

Lake Sturgeons inhabit large lakes and rivers throughout most of Ontario and are found in several provincial parks, including:

They are a living fossil whose body shape and morphology have existed for millions of years!

A juvenile sturgeon captured in Lake Superior. A juvenile sturgeon captured in Lake Superior

The lake sturgeon, like all sturgeons, preserved its skeleton made of cartilage (not bone!) and its shark-like tail fin that first appeared in its ancestors 419 to 359 million years ago. .

Since then, they have changed slightly.

Sturgeons, as we recognize them today, began appearing in the fossil record between 174 and 201 million years ago and have been almost indistinguishable from modern sturgeons for between 100 and 94 million years.

Their persistence today can be explained by their life history strategies.

Lake sturgeon grow to enormous sizes (the Ontario record is over six feet!) and can live over 100 years. In fact, a 208-pound lake sturgeon caught at Lake of the Woods in 1953 was 154 years old.

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person holding sturgeonAn adult lake sturgeon captured in Lake Superior to be tagged with a passive integrated transponder (PIT) to better understand sturgeon movement

In addition to the ability to grow, sturgeon have thick bone armor called scutes, making them a difficult meal for any predator.

All of this, along with the fact that they feed on invertebrates, small insects and other abundant organisms that live at the bottom of our waterways, has allowed them to persist in this form for millions of years.

From hassle to caviar

Unfortunately, not even their large size and thick armor could defend them from the threats that caused their decline.

The tail fin of an adult lake sturgeon.The tail fin of an adult lake sturgeon

Early settlers despised Lake Sturgeon for its ability to destroy fishing gear and euthanized it as a nuisance species.

Commercial markets began to appear throughout Ontario for fresh, dried, smoked sturgeon meat and caviar after 1860, reaching their peak in 1900.

In addition to food, the sturgeon was a source of oil, leather and isinglass, a product used in the production of beer and wine.

Commercial trapping was the largest contributor to the population collapse in the 1920s, while additional factors such as pollution, the creation of dams blocking access to spawning grounds, and invasive species present ongoing threats to the population. Sturgeon Lake.

This is in contrast to the indigenous peoples of Ontario who hold these fish in high regard.

Elders report that sturgeon are used as a food source, scrapers are made from shields, arrowheads are made from tail bones, and containers are made from their skin.

Sturgeon also plays an important role in spirituality.

Today, lake sturgeons are considered an at-risk species in Ontario.

The Ontario Great Lakes – Upper St. Lawrence populations are classified as Endangered, the Saskatchewan – Nelson River populations are classified as Threatened, and the southern Hudson Bay – James Bay populations are classified as Endangered. special concern.

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mapCurrent and historical distribution of lake sturgeon in Ontario

As a threatened and endangered species, the lake sturgeon populations of the Great Lakes – Upper St. Lawrence and Saskatchewan – Nelson River are protected under the Endangered Species Act, 2007 (THAT).

Lake Sturgeon being tagged PIT

These populations also receive habitat protection and a A recovery strategy has been released that provides scientific advice on actions to take to help recover Sturgeon Lake in Ontario.

Population monitoring is also carried out in the three populations.

For information on Lake Sturgeon fishing, see the Ontario Fishing Regulations.

The Province of Ontario is conducting research on all Lake Sturgeon populations to identify and assess migration barriers, improve water management in hydrological reservoirs, assess subpopulations whose population sizes and trends are unknown, and determine the effects of invasive species on The Sturgeon.

Research continues at Kakabeka Falls to evaluate lake sturgeon spawning success.

A walk through Jurassic Park

For today’s dinosaur hunters, you may still catch a glimpse of this Ontario dinosaur.

person holding a large lake sturgeonAdult lake sturgeon captured during a survey in 2014

Lake sturgeon can sometimes be seen spawning in late spring at the base of rapids, dams or waterfalls.

Kakabeka Falls Provincial Park is a great place to watch sturgeon spawn. Safely watch the sturgeon from the park’s viewing platform, high above the Kaministiquia River.

view of kakabeka falls

The next time you walk along the river or take a dip in Ontario’s many lakes, think about the gentle giants who persevered for millions of years but today need our help to survive.

Please respect waterways by keeping them free of trash, do not leave fishing lines, and clean your equipment between uses.

Keep your eyes open, you never know what you might see on your next park adventure.

If you’re lucky, it could be a dinosaur.

This is the sixth edition of our 2023 Species at Risk series.

Read our previous edition: A ghost in the attic