Connecting people with nature in Ontario's Mississippi Valley

Ecologist used paleolimnology to take naturalists ‘back in time’

Ecologist used paleolimnology to take naturalists ‘back in time’

By Pauline Donaldson

On Thursday November 24th , we hosted the third speaker in our series, “Change in our Natural World”. Guest speaker, Dr. Brian Cumming, is Associate Professor in the Paleoecological Environmental Assessment and Research Laboratory at Queens University (PEARL). The PEARL scientists use techniques of paleolimnology (study of fresh water ecosystems in the past) to provide an historical perspective on environmental change. Data collected is used to determine natural environmental variability in the past, and to test models used to study current global environmental change.

Dr. Cumming’s research can track natural changes in an ecosystem over impressively long time periods (millions of years) in the past, while at the same time uncovering detailed decade by decade information about this time period. Sophisticated sampling techniques and analyses can reveal patterns of temperature, acidity and other changes in a lake over long periods of time. Changes in lake temperature, for example, affect the type of algae and other species which will flourish. These changes can be deduced by analyzing which types of fossil algae are predominant in the lake sediment deposited during a particular time period. Cylindrical cores removed from lake bottom sediment are first calibrated to establish the relationship between depth and timing of deposition (age).

Some of the background work which was done to establish the protocols and the relationships between algal type and the environmental conditions in which they flourished, were done in British Columbia where there is a huge diversity of lake types. This knowledge was then applied when examining sediment cores from lakes in the Canadian Prairies.

From these studies, Dr. Cumming has concluded that abrupt millennial-scale shifts in climate were likely common on the North American continent in the past six thousand years. These natural shifts are more severe and prolonged than the meteorological and historical records indicate. Although the mechanisms behind these changes are unclear, the findings have profound implications for the natural environment and the infrastructures of our communities. Water management plans, for example, may be inadequate if predictions of variations in water availability and water levels are based only on short-term records.

The presentation concluded with many good questions from the audience, followed by refreshments and further discussion. Please join us again in the New Year, on January 19th, when we welcome the fourth guest speaker in the series “Change in our Natural World”. Art Dyke will tell us about “Change in the Arctic”.

 

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Naturalists explored the nature of bees

Press Release
Mississippi Valley Field Naturalists
Submitted by Sheila Edwards, MVFN member
October 28, 2005

Naturalists explored the nature of bees 

BeesBeekeeper John Nelson captivated his audience of naturalists on Thursday, October 20th during the regular meeting of the Mississippi Valley Field Naturalists (MVFN) at the Almonte United Church. The talk was of interest to honey consumers, amateur bee keepers, biologists, and all those who have paused in their busy day to watch a bee visit a beautiful flower.

Following introductions, an excellent documentary short film was shown. The film was produced by Jim Robertson and featured Mr. Nelson himself, and of course his bees. Afterwards Mr. Nelson handled questions which led to an in-depth exploration of bee keeping. There was no doubt about the interest shown by the audience. Mr. Nelson commented that he had never received such an excellent response to his favorite topic. Many fascinating and likely little known ‘bee facts’ emerged. For example:

1. Drones can be quite mysterious in their foraging patterns, sometimes searching out flowers 5 km away.

2. Local beekeepers need electric fences to protect the hives from skunks, raccoons, and bears.

3. It can take ~ 11 million flowers to produce one kilogram of honey.

4. The first queen bee to hatch, will kill all the other queen larvae, and then take off in the mating flight. If a hungry Flycatcher spots this awkward morsel, the only queen becomes lunch, and the hive will stop producing.

5. Domestic hives in Canada are at high risk of a fatal mite infection which is treated for each spring. Current research is directed at this problem.

6. If poor weather hits while a drone is out foraging, it may hide in a protected area, such as under a leaf, possibly not returning to the hive until the next day.

7. Similar to maple syrup production from sap, the bees create honey from nectar by concentrating it about 40 times.

8. Most important of all, buy local honey! Some honey sold in Canada may be a mixture of imported and domestic honey.

Host for the evening, Mr. Noel Noyes-Brown, thanked the speaker and presented him with a gift basket. The next indoor MVFN event will be Thursday, November 24th when we will host guest speaker Brian Cumming as part of our continuing series on “Change in our Natural World”. Dr. Cumming is an Associate Professor at Queen’s University and an expert in ecology and paleolimnology. For more information on this and other MVFN events, please visit our website at www.mvfn.ca.

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