Date: 09/08/2010

Number: 100

We have had some interesting observations during the week. Since Sunday, we have had about 100 monarchs flying around ten acres of red clover during the day and roosting each night in three distinct, tight, clusters on big maple trees 75 metres from our front door -- always on exactly the same branches, same leaves. During one cold, wet, and windy day they did not move, and spent about 36 hours on their roost. This roost gives shelter from the fierce west winds that blew hard for a couple of days.

Yesterday (9/8), after a breezy cool day with occasional showers and long sunny periods (during which they were feeding in the clover) they started heading for the roost around 5pm. Again, same branches, same leaves. This morning (Thursday) when the temperature reached about 15 degrees around 10 am, they began leaving the roost. And tonight they are gone. They appear to have moved on, perhaps because of today�s light favourable winds.

We did manage to record some of this -- about three hours of HD video and 300 stills. Some wonderful slow motion shots as they all open and close their wings on the roost as each new arrival checks in. It looks like the Wave at a football game.

This has been an exceptional year for monarch caterpillars. We have lots of milkweeds on the farm, but the monarchs laid their eggs mostly on isolated or sheltered milkweeds (under our main window for example) and avoided the dense stands of milkweeds in thick grasses. Do they know that a caterpillar would have a difficult time moving through thick grasses in search of a place to pupate....? Many were laid on milkweeds growing in bare earth on the fire break surrounding our tall grass prairie.

Every chrysalis we have found has been at least a metre away from the original milkweed, and none on the actual milkweed that fed them. There were about a dozen under the eaves of our house, some still there. At the pond, the butterflies show a strong preference for swamp milkweed, and the caterpillar moves to an adjacent plant to pupate. We had to rescue a few caterpillars that were on milkweed plants standing in water.

The real test of monarch mysteries will be next season. Will monarchs use the same roosts on the same branches in our maples? If so, who told them? Actually, we think that the two fields of red cover held them here. All of our neighbours’ fields yielded an unusual third cut of hay this summer and are now bare with no flowers. The two fields west of our cabin were spared when our neighbour, who cuts the hay, had a mechanical problem. And we have lots of wild flowers in an old meadow.

Forwarded by Don Davis

Madoc, ON

Latitude: 44.5 Longitude: -77.5

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