Thursday, July 7, 2011

Searching for Monarchs

Rio Salado first generation, 4/11
By June I'm already looking for monarchs. This year we saw the last one in the Phoenix area in May. Tatsuyo was surprised to find a monarch visiting her milkweed briefly to nectar near the middle of the month. The last time I saw any monarch butterflies was at Rio Salado in April when the first generation eclosed and left a few days later. Despite tagging 70 monarchs in the Phoenix area this spring, we have not heard of any sightings that would help us learn where they fly after leaving the Valley of the Sun.

Bob and I originally planned to visit the Springerville area at the beginning of June, but the Wallow Fire stopped that trip. We did drive up the weekend of June 18th and again this last weekend. While the fire never reached the Wenima Wildlife Area, heavy smoke did. We didn't know what effect the smoke would have on the butterfly population. Both weekends we visited, the primary pollinator nectar plant was the dogbane in bloom. In June we were blasted by 45 mph winds and red flag warnings both days and we saw little butterfly activity of any kind - not too surprising. But this last weekend we were startled by the absence of queen butterflies as well as monarchs despite good butterfly viewing conditions. Two years ago we found fresh and new looking monarchs and queens at Wenima in early July. We visited in mid-June last year and found five monarchs and a good number of queens. But this year the absence of orange wings was striking.

Wenima Wildlife Area - Springerville

The ground was dry, cracked, brittle, parched. The grassy fields were like straw and stunted.

Asclepias speciosa
Yet despite the harsh conditions, milkweeds were raising their heads and Showy Milkweed, Asclepias speciosa, was beginning to bloom. Pollinators were busy, but we didn't find any butterflies visiting the fragrant flowers nor any eggs on the leaves. We spotted some new stands of Showy Milkweed in a field not seen the previous three years. Did we just not see them earlier when the grasses were lush and tall, or were these indeed new plants? I'll have to search field photos from the last two years to know for sure.

Asclepias subverticillata

Horsetail or Poison Milkweed, Asclepias subverticillata, was also pushing through the grasses. While buds were already forming, the plants were noticeably shorter and drought-stressed. A year ago we saw queen butterflies laying eggs during mid-June on these milkweed favorites, but now no orange wings appeared despite the perfect temperature and weather conditions.

Wenima, Southeast meadow
Even though the fields were dry, fresh new growth was pushing through the surface by the old sunflower stalks. They seemed to stretch out to grasp any drops of summer rains that so far have missed these fields. We felt a sense of sadness as we walked these once beautiful and lush meadows noticing the absence of wings and things as we once knew them. So many different factors were converging: the drought but also the unhealthy and dire smoke conditions swirling over this important breeding ground for an extended period of time. The adult butterflies could leave but heavy smoke may have affected any larvae or pupae development. However, we did not see any remnants of pupae to indicate this was the case. The drought effect is pronounced. But the prediction is for a normal monsoon season so hopefully rains will soothe these parched meadows with new life.

Our dream is to return to Wenima in a few weeks and see it once again teeming with life. But I am concerned about reports from the Eastern monarch population pointing towards the possibility of a lower than expected fall migration again this year. Dr. Lincoln Bower reported in mid-June that he visited northern Wisconsin with Su Borkin and Julie Hein for their 25th year monarch adult and immature census conducted from June 10 to 12. They counted lower adult monarchs than usual. They found 70 eggs  on 100 Asclepias syriaca plants and no larvae at all. At the time of their observations the milkweed was only about 8 inches tall.  Dr. Chip Taylor shared his thoughts about the possible effect of weather in the summer breeding areas that could effect the fall migration. Much can change in the monarch's favor in the next six weeks. For us in Arizona the monsoon rains could be a blessing. Rain can soothe our drought and dampen our temperatures. For the monarchs, that is all good.

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