Migration Rate Math
Who saw the strongest migration this week?
October, 2006

Here are a few of this week's observations. Read the comments and calculate the migration rate for each. Record this fall's most impressive observations on your Fall 2006 Record Sheet. Add your favorites to your own Migration Highlights Map. (Don't forget: You can collect more observations from our migration maps and weekly updates.) Please report your sightings!

10/12/06 Kerrville, TX (30.03 N, -99.09 W)
Yesterday evening (10/12), as the front came through Kerrville, I was fortunate enough to be outside. I happened to look up and for 15-20 minutes, watched hundreds upon thousands of Monarch butterflies riding the front, heading south. They extended from 20 ft above to ground to (I’m guessing) 500 ft. It was an awesome sight!

10/13/06 Comal County, TX (29.81 N, -98.30 W)
The front blew in this afternoon. The first puffs of air from the north brought many Broadwing Hawks between 5:30 and 6:00 PM. The most impressive migration though was Monarch butterflies. From 5:50 to 6:05 there were unbelievable numbers floating along at 30 MPH at altitudes of 50' to 300 yards. I was seeing about 50 per binocular field of view continuous, no matter where I looked in the sky.

10/12/06 Balcones Canyonlands, TX (30.34N, -97.75 W)
We got our wind shift for the strong cold front about about 2:30pm and immediately the sky was filled with Monarchs drifting on the strong tailwind. They are passing overhead in the lower couple hundred feet of the air column at a rate of about 30 to 50/minute.

10/16/06 Del Rio, TX (29.85 N, -100.88 W)
Observed oveapproximately 1,600 monarchs flying over Del Rio Middle School. The majority were flying over between 8:45 and 9:30 a.m., 700 estimated.

10/14/06 Austin TX 30.2304 -97.7144
We are at the crest of a large hill just west of Austin overlooking greenbelt. We have a steady trickle (1-4/minute) this morning.

UTLEY TX 30.1817 -97.4206
I am outside doing a hawk watch with 1,000’s of raptors. At 3:39 winds shifted from the north and the sky is full of high altitude monarchs. Estimating 240-300 + in 10 minutes.

10/13/06 Tarpley TX (29.64 N, -99.22 W)
At 10:30 a.m., I was watching a flock of Turkey Vultures that appeared to be migrating south when I begin to notice small birds with them. Closer examination revealed thousands of Monarchs migrating south riding the winds of the front that passed last night. Using 10X binocs, I found Monarchs from 200 feet agl to as high as I could focus (estimate 1000 feet agl). Every time I changed focus, more Monarchs came into view. None were seen at ground level.

10/14/06 Port Lavaca. TX 28.5289 -96.6789 There was another flurry of monarchs crossing Lavaca Bay near the causeway at noon today. For an hour, Altus and I observed about 1 monarch a second between 50 and 300' zipping along with a 20 mph NE wind, over and past everything, heading across the bay, there were times we had three and five out the front

How would you handle these?

Oct. 14 and Sunday Oct. 15.
In the evening several of the large live oak trees along the road were full of Monarchs. Other trees off the road may have also had butterflies. During the day there were 5 to 10 in sight at all times as we drove - just fluttering around. This occurred over the entire ranch (1184 acres).

10/13/06 Mineral Wells, TX (32.79 N, -98.11 W)
Each class spotting aprox. 5 monarchs/min. for 15 min ea. class for a total of 300 Monarchs. All butterflies were in flight.

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