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October 13, 1997
St. Mark's National Wildlife Refuge, our sixth stop on our refuge hot spots tour, is located along what is known as the Big Bend coast of Florida, approximately 30 miles due south of Tallahassee. Generally, St. Mark's sees large concentrations of monarchs moving through the refuge at this time of year. However, when Tanya conducted her last official count on Saturday, October 11 she reported only 17 Monarchs! The low number of Monarchs in Florida is especially surprising this year, since monarchs have been seen in unusually large numbers in other regions. Just up the coast in New Jersey for example, this year's migration is breaking records set in previous year. Researchers are questioning: "Where could all the Monarchs be?" and "Why haven't they arrived yet?" Think back to the weather and migration patterns which have been reported from observers this fall. We've seen that the northerly winds which follow cold fronts tend to push waves of Monarchs southward. Northern Florida is now experiencing what meteorologists are calling a "heat dome". A large mass of hot, dry air is hovering over a large region of the state. Florida has had above average temperatures and very little rain in the past several weeks. According to the latest forecast, no break in this weather pattern is in sight. Cold fronts are simply not moving through the area and, therefore, neither are the Monarchs. This example shows how the migration pathway can vary from year to year, due to differences in weather. In years when the Eastern States consistently experience northwest winds, masses of butterflies are probably forced to hug and follow the Atlantic Coast, all the way down to Florida. However, if northwesterlies have not been consistent, which they have not this year, Tonya says they can disperse in any number of different ways, and take a more direct route to Mexico. This seems to have occurred this year. On to Mexico--or Maybe Miami? Where do the Monarchs that do come through St. Marks ultimately go? Through tagging, people are beginning to explore this in more detail. Tonya VanHook has tagged the over 3,000 Monarchs at St. Marks. So far, 6 individuals have been recovered and they tell an interesting story. Three tagged butterflies were recovered to the east of the refuge, on the Gulf Coast near Sarosota, FL. The other 3 were found west of the refuge. While this is a very small sample, it suggests the Florida Gulf Coast is like a fork in the road for migrating Monarchs. After reaching the coast at St. Marks National Wildlife Refuge for example, some may move in a westward direction toward Texas and ultimately to Mexico. Others may travel to the southeast, to points along the Florida coasts. Some may go to the Miami area, where monarchs are known to breed throughout the year. Others may even cross the Gulf of Mexico. Monarchs sightings have been reported from oil rigs stationed in the Gulf's waters. They have been sighted in the Bahamas and Cuba, as well. There are many unanswered questions about monarchs traveling to and through the Gulf Coast region. Students who live in the Gulf Coast States can help discover the answers to questions such as these:
Students in all regions can help by reporting the date they see their last monarch this fall. You may
be surprised to see how late in the season monarchs can linger. Just yesterday a monarch was seen in Minnesota--and
tonight it's snowing!
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