25 May 2012

Life in Wascana Lake: Aquatic ecosystem studies

By Marie Powell

I had the chance to learn more about Regina's man-made Wascana Lake recently in a new speaker's night at the Saskatchewan Science Centre.

One of the speakers was Dr. Richard Vogt. He has a postdoctoral fellowship in biology at the University of Regina to study structure and functioning of aquatic communities and ecosystems. He works with Dr. Peter Leavitt in the Limnology Lab, using the long-term database of lakes in the Qu'Appelle River catchment to explore important questions in limnology (meaning the study of freshwater lakes and marshes) and aquatic ecology.

Limnology lab scientists monitor Wascana Lake as one of six major lakes in the Qu'Appelle Valley wastershed, Vogt told about 30 people who came to hear three speakers on water issues on May 4, to open the exhibit "Water's Extreme Journey." Vogt grew up in Ontario and took his PhD in Aquatic Community Ecolology from the University of Quebec in Montreal. He said his colleagues would envy the U of R for its “rare and valuable” database of samples, collected every two weeks – in all seasons – for some 16 years.

Part of Vogt's studies with Leavitt include the effect of Regina’s “Big Dig” in 2004. During the $18-million Wascana Lake Revitalization Project, or “Big Dig" as it's known locally, Wascana was dredged from about 1.5 metres to about five metres in depth, removing over 1.3 million cubic metres of soil in about four months. (More on the dig can be found in The Big Dig: The Miracle of Wascana Centre by Bob Hughes.)

Vogt's studies show that surprisingly, the project hasn’t affected Wascana Lake the way scientists predicted it would. For example, scientists predicted the dredging would make the lake less clear and cause an increase in algae. Up to then, he said, rooted plants locked up the nutrients in the lake sediments, providing a habitat for zooplankton that graze on algae. Plants growing all the way to the water’s surface would get caught in people’s boat oars, and have to be mulched periodically.

But the dredging caused “no change in the most important water quality indicators” in the lake, Vogt said. Although the overall number of plants was reduced, there has been no increase in algae, and no decrease in clarity. There are some differences in algae species that thrive in the lake, but “for the most part we see a similar diversity,” he added.

For more information, check http://www.uregina.ca/biology/faculty/Leavitt/labsite_files/wascana.html

Marie Powell is the author of Dragonflies are Amazing! (Scholastic Canada, Grade Two Guided Reading, 2007). (Note: A version of this material appears in Marie's article in Metro Regina print edition, May 10 2012. Photo: Wascana Lights by L L Melton.)

21 May 2012

Interactions Between Species

http://www.youtube.com/watch?v=lC3AkGSigrA Here's a treat for you: a video on the interactive play between bottlenose dolphins and humpback whales. It's fun to watch them play and listen to how scientists study this phenomenon. Enjoy!

18 May 2012

Alien Super Powers Are on Earth!

A headline like this in the National Inquirer might actually be the truth. In my book Amazing Animals, I included a short paragraph of information on the strength of ants. As one of the most numerous life forms on earth, ants have developed truly mind boggling features. Did you know that, annually, ant colonies consume more meat than lions? Did you realize that ant societies are as complex, but perhaps fundamentally smarter, than human societies? Ants have developed into workers that each have specific tasks aimed at the general welfare of the colony. Not one ant acts in its own best interest. Communication and cooperation are there secret weapons to thriving societies. Some ants are destined to be shepherds and actually herd small bugs, mealy bugs, which they have domesticated, much like humans herd and tend cattle. Scientists have studied ants in elaborate laboratories and made staggering discoveries. They tested the ants under circumstances similar to astronauts and athletes. In the process they have discovered complex structures such as a democratic society in which each ant is valued, and even discovered that ants have been using sperm banks, probably for much longer than humans have. By studying huge subterranean structures, they discovered that ants control their environment by creating chimneys that transport toxic air out of the chambers, bring in fresh air and regular temperatures like air conditioning systems. They separate food from waste, keep their homes clean and even use disinfectants to keep the colony from getting sick. Do yourself a favour - sit back and relax, to watch this extraordinary documentary. It’s nearly an hour - shorter than a feature film but every bit as intriguing and amazing as a sci-fi movie: http://tv.naturalnews.com/v.asp?v=a4e23a5c65f22bdf4a72b3a9cc34d1f6 The Ant
Painting from the book Amazing Animals by Margriet Ruurs, illustrated by W. Allan Hancock

6 May 2012

Hockey Science

Today's post is just for kids.
It's the playoffs for Lord Stanley's cup and even though my hockey team was knocked out in the first round, it doesn't mean I've given up on the game.

My writing partner, Leslie Johnstone and I have a new book on Hockey Science, soon to be published by Scholastic Canada.  The book has 25 really cool experiments but some activities which we thought we terrific were cut by the editor.  We aren't complaining, but this was one activity which we really liked. So- rather than lose an experiment, we thought we would share it with you. 

The image above is the cover for the book. Great job by a fabulous illustrator.

Tasty Ratios
You may not have thought about this, but hockey involves a great deal of math. Anytime you quote a player’s statistics or recite win/loss percentages you are using math. Here’s a tasty way to think about advantages when a team is short a player.

NOTE: If you have a food allergy check with a parent before using any of the ingredients

You Will Need

4 pieces of round pita bread or small round tortillas
Peanut butter or almond butter (do not use if you have nut allergies)
Butter knife

What To Do

1 Spread peanut butter or almond butter over the pita or tortilla and drizzle a bit of honey over it.
2.  Use a knife to divide two of the pitas into 3 equal sections. Cut the pita and set aside 4 of the 6 sections.
3.  Use a knife to divide the other two pitas into 4 equal sections. Cut the pita and set aside 5  of the 8 sections. Which gave you the greatest servings of pita- the one cut into thirds or the one cut into fourths?
4.  Eat the pita hockey snacks.

What Happened?

You have two pies. Someone offers you 4/3 of the pies or 5/4 of the pies. Which offer would you choose to receive the greatest serving of the pies? You discovered that 4/3 is greater than 5/4. But what does that mean for hockey? Consider power plays: If a team is playing 4 against 3, it means they have a greater advantage than if they were playing 5 against 4.

Did You Know?

You also created a great science snack. The pita provided a carbohydrate and the peanut butter gave you a protein. 

 Your body needs carbohydrates and proteins after a strenuous workout. In fact, nutritionists recommend that you have some kind of carbohydrate such as fruit, or juice shortly after exercising. This gives you more energy and helps to restore your levels of glycogen, the chemical your body makes to store carbohydrates for later use. Proteins from foods such as nuts, meat or milk give your muscles the amino acids they need to not only recover from the workout but also to rebuild.  It is recommended that you consume both carbohydrates and protein within 30 minutes of a strenuous workout. If you wait longer than that period of time your body will take in or absorb less glycogen.

2 May 2012

Palaeo-Yukon Rocks!

By Claire Eamer

A couple of weeks ago, I posted a blog entry here about archaeological and palaeontological discoveries high in the Yukon mountains. Well, we're at it again! But this time, the big find is in a suburban Whitehorse basement.

Craig Duncan and Sandy Murphy just wanted to lay a new power line into their home in the Whitehorse suburb of Porter Creek, so last week they started digging a trench through their basement -- and struck bone! Before you say "haunted house" and "horror movie" though, relax. This bit of bone was attached to a hoof.

They stopped digging, collected as many bits of bone as possible, and took them to Grant Zazula, the Yukon Government Palaeontologist. He was -- and is -- thrilled. It's the remains of a bison. In fact, when the palaeontologists went back to Porter Creek and excavated further, they found an almost-complete skeleton of a bison.

Bison disappeared from the Yukon about four centuries ago, and no one knows why. The bison here now were introduced just a few decades ago. This skeleton might provide clues about the animals that lived here in the past and why they disappeared.

And how far in the past? The skeleton will be carbon-dated, but in the meantime, the palaeontologists are making bets. It could be as much as 10,000 years old!

For more detail about the find, see the Whitehorse Star story or this story that appeared in the Globe and Mail.