When the milkweed is in full bloom and its sweet smell fills the air, the time is right for the monarch butterfly to produce the offspsring that will travel to the traditional wintering grounds of central Mexico.
The journey south is a dangerous one, but while making the trip has its challenges, surviving winter in Mexico has its own problems. In 2002, severe weather conditions resulted in the loss of 80% of the wintering populations. Many, many millions of monarchs died from the cold.
Unlike migrating birds, monarchs do not live long enough to make the trip down and back. To solve the problem, the wintering monarchs produce a new generation of monarchs in the area surrounding the Gulf of Mexico as the butterflies move north each spring. The females continue to lay eggs on the flowering milkweed plants along their route to Canada. These new butterflies find their way north without previous generations to show them where to go.
In summer, monarchs produce many summer generations and have the capacity to recover their winter losses. But, if Canada has a cold wet summer or an early snowfall it can reduce the length of the egg-laying season and therefore fewer summer generations are produced.
Monarchs are very sensitive to any environmental disturbance that reduces the crop of milkweed and other flowering plants required to feed the larvae and provide fuel for long distance migration. As well, indiscriminant herbicide and insecticide spraying can devastate a generation of monarchs, making recovery that much more difficult.
To increase awareness, the monarch has been listed as a species of special concern, and by working together Canada and Mexico have created an international network of monarch butterfly reserves. In Canada they include Long Point National Wildlife Area (Lake Erie), Point Pelee National Park (Lake Erie) and Prince Edward Point National Wildlife Area (Lake Ontario). Many millions of monarchs congregate in these areas before they head out across the Great Lakes. Conditions must be perfect before they leave: 60-80% cloud cover, temperature about 20 degrees Celsius and moderate northwest winds to push them along.
Help the monarchs by planting native flowering plants that provide blooms from May through October. Where the milkweed species is left uncut it provides food for the larvae and a place to spin a cocoon. Goldenrod, although not a favourite with alergy sufferers, provide an important nectar source for all pollinator species. We can reduce the use of insecticides and herbicides where possible, especially along roadsides and fencerows. This is often difficult to achieve but consider trading the sprayer for the scythe or the sickle.
There are several websites dedicated to the monarch. For information on nectar-producing flowers, or to learn about volunteer-based monitoring programs such as those offered by Monarch Watch visit: http://www.monarchwatch.org/
Photos by Clayton Rollins
The journey south is a dangerous one, but while making the trip has its challenges, surviving winter in Mexico has its own problems. In 2002, severe weather conditions resulted in the loss of 80% of the wintering populations. Many, many millions of monarchs died from the cold.
Unlike migrating birds, monarchs do not live long enough to make the trip down and back. To solve the problem, the wintering monarchs produce a new generation of monarchs in the area surrounding the Gulf of Mexico as the butterflies move north each spring. The females continue to lay eggs on the flowering milkweed plants along their route to Canada. These new butterflies find their way north without previous generations to show them where to go.
In summer, monarchs produce many summer generations and have the capacity to recover their winter losses. But, if Canada has a cold wet summer or an early snowfall it can reduce the length of the egg-laying season and therefore fewer summer generations are produced.
Monarchs are very sensitive to any environmental disturbance that reduces the crop of milkweed and other flowering plants required to feed the larvae and provide fuel for long distance migration. As well, indiscriminant herbicide and insecticide spraying can devastate a generation of monarchs, making recovery that much more difficult.
To increase awareness, the monarch has been listed as a species of special concern, and by working together Canada and Mexico have created an international network of monarch butterfly reserves. In Canada they include Long Point National Wildlife Area (Lake Erie), Point Pelee National Park (Lake Erie) and Prince Edward Point National Wildlife Area (Lake Ontario). Many millions of monarchs congregate in these areas before they head out across the Great Lakes. Conditions must be perfect before they leave: 60-80% cloud cover, temperature about 20 degrees Celsius and moderate northwest winds to push them along.
Help the monarchs by planting native flowering plants that provide blooms from May through October. Where the milkweed species is left uncut it provides food for the larvae and a place to spin a cocoon. Goldenrod, although not a favourite with alergy sufferers, provide an important nectar source for all pollinator species. We can reduce the use of insecticides and herbicides where possible, especially along roadsides and fencerows. This is often difficult to achieve but consider trading the sprayer for the scythe or the sickle.
There are several websites dedicated to the monarch. For information on nectar-producing flowers, or to learn about volunteer-based monitoring programs such as those offered by Monarch Watch visit: http://www.monarchwatch.org/
Photos by Clayton Rollins
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