Date: 10/14/2016

Number: 520

This is the first day this year we have seen directional migration. This was a slow motion event difficult to notice casually.

Rained early morning. low 57. Rain ended by 0915. Cleared off late morning. Monarchs started flying by 1100. Clearly southbound by 11:30.
Most were flying right above tallest grass or forbs. Some were high from passing over the house then most quickly descended. Direction was SSW essentially straight into the wind. Wind light about 5, with occasional gusts to 10. Gusts would blow them off course, but otherwise steady progress. A few stopped to feed from flowers.
Started timed counts from back porch with Monarchs flying across or away. at 1345. Observation view about 70 yards. 99 in 90 minutes. Stopped briefly then 52 in 20 minutes. Total 151 in 110 minutes = 82 per hour. No more timed counts but still flying at 1730.
6 hours at 82 per hour is 492. Reported total includes a few more I saw feeding while on the way to check roosts later.

Speculation I could have assumed that the stream was wider than 70 yards, which is not unreasonable since there is no obvious reason they would be strongly channeled by terrain. If anything I would expect terrain to channel them away. If I scaled up for a wider width, I could get 5000 just on our property by assuming they were crossing the open meadows east and west of our house.

Glen Rose, TX

Latitude: 32.1 Longitude: -97.9

Observed by: Gregg
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