Date: 09/14/2011

Number: 500

September 28
Clear. Temperature in low 50s. Light NW wind ~ 5 mph.
4 monarchs on east side of white mulberry ~15' up in the tree. Same tree had a roost of ~ 125 last week. Unknown if these are "stragglers" from that group or new migrants from further north.

September 22
Site visited from 8:25 to 8:45 a.m. Mostly sunny w/high thin clouds. Hatfield temperature 50 degrees @ 8:53 a.m. (from NOAA.gov web site). Overnight low ~46 degrees. Light NW wind.

~ 125 monarchs seen in 6 different trees. A few were beginning to forage while those still on the roost were skittish, readily flying if too sudden of movements were made.

September 21
Estimated 250 to 300 monarchs roosting in four different trees along fence line. Sept. 20/21 overnight low of 47 with temperature 50 degrees at Hatfield @ 7:53 a.m. (NOAA.gov web site). Light wind @ 7:15 a.m. upon arrival with WNW winds ~ 5-10 mph when I left at 8:15. Clear & sunny from sunrise until departure.
Main roost (~125 monarchs from count in photos) on east side of tree with other roosts on south or southeast side. Most were still on the roost but at least beginning to spread their wings when I left @ 8:15 though a few were beginning to fly. Photos & short video clips taken.

September 19
I stopped by the site on my way in this a.m. and saw a total of about 100 to 125 monarchs on three different trees in the same location of the previous report.

September 18
Site checked from 8:05 to 8:30 a.m. Temperature ~54 (NOAA temp at Hatfield @ 7:55 a.m.); moderate fog; no wind until departure when light NW wind was beginning. Light rain & mist in area @ sunset the previous evening (as indicated by radar). Moderate to dense fog night of Sept. 18-19 with 52 as forecast overnight low. Three groupings on three different trees with largest having ~ 70 monarchs as counted in photo taken. Two groups on south side of two different trees about 12 to 15' off the ground. Third group on NE side of tree @ about same height. Not all of trees on north side are visible as they are over adjacent private property.

September 14
Roost was in scattered white mulberry (Morus alba)in a fence row between The Nature Conservancy's Dunn Ranch & private property to the north. Observed from ~9 a.m. to 10:30 a.m. (Sept. 15) with temperature in low to mid 50s with a light to moderate NE breeze. Scattered light frost the night before. Estimate 300 to 500 monarchs total in about a half dozen hedge. Monarchs moved to sunflowers (Helianthus sp.) in the immediate vicinity when they left the roost between 9:30 & 10:30. Most of the monarchs roosted on the south and west side of the hedge trees the night of Sept. 14-15. I counted as many as 23 in one photo that came out blurry but there were numerous small groups on several trees.

In looking at the one photo more closely, I believe the sunflowers were sawtooth sunflowers (Helianthus grosseserratus). Also, I forgot to mention in my report that most of the monarchs roosted on the south and west side of the hedge trees the night of Sept. 14-15. I counted as many as 23 in one photo that came out blurry but there were numerous small groups on several trees.

Almost all of this part of Dunn Ranch was in fescue pasture 6 to 8 years ago but is now in different stages of prairie reconstruction. It has been planted to prairie vegetation of various quality, composition, and diversity through the efforts of Randy Arndt, Preserve Manager, and his staff. Composition varies depending on the seed harvest the year before plantings were done, the weather conditions the year of planting (and subsequent years), amount of competition from invasive species, and soil type depending on past land use and topographic position.

Nectar species available during migration include saw-toothed sunflower (Helianthus grosseserratus), New England aster (Symphyotrichum (Aster) novae-angliae), and a small amount of rough blazing star (Liatris aspera). I'm by no means an expert on nectar sources. Other fall possibilities might include several other asters - Aster ericoides, Aster oolentangiensis, Aster drummondii, Aster pilosus (weedy in the plantings - we'd like to get rid of or at least reduce it), and Aster praeltus; goldenrods include showy goldenrod (Solidago speciosa) (uncommon to rare at the ranch), Missouri goldenrod (Solidago
missouriensis) (uncommon at the ranch), old field goldenrod (Solidago nemoralis), tall goldenrod (Solidago altissima) (abundant and weedy - we'd like to greatly reduce it as it is practically taking over some plantings), stiff goldenrod (Solidago rigida), grass-leaved goldenrod (Euthamia (Solidago) gymnospermoides), grass-leaved goldenrod (Euthamia
(Solidago) graminifolia); sweet coneflower (Rudbeckia subtomentosa); two or three other sunflowers, and likely others I'm forgetting.

Milkweeds providing summer nectar and larval food include butterfly milkweed (Asclepias tuberosa) (common though pod production for seed is spotty and unpredictable), purple milkweed (Asclepias purpurascens) (uncommon to rare though we are trying to collect seed to add to the seed mix - like butterfly milkweed, pod production is unpredictable and usually light), swamp milkweed (Asclepias incarnata) (common in swales on the unplowed prairie and some recovering swales on disturbed areas - pod production more consistent and predictable), Sullivant's or prairie milkweed (Asclepias sullivantii) (rare with pod production very limited in most years so far), common milkweed (Asclepias syriaca) (common to abundant with pod production the most consistent of any of the milkweeds
- doesn't usually compete to the point of "smothering out" other forbs so we don't currently manage against it), whorled milkweed (Asclepias
verticillata) (common on disturbed sites in some years), tall green milkweed (Asclepias hirtella) (uncommon to common depending on the site
- fairly consistent seed producer).

Dunn Ranch is about 3,000 to 3,500 acres. The Nature Conservancy also owns Pawnee Prairie to the NW of Dunn Ranch about 2 miles. It is ~ 500 acres and is adjacent to the Missouri Deparment of Conservation's Pawnee Prairie which is 475 acres.

Hatfield, MO

Latitude: 40.5 Longitude: -94.2

Observed by: Tom
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