Tuesday we embarked on a road trip to northeast Nebraska in search of marsh skippers and coppers where we were joined by our friends Pat and Dianne Miller. We started our search at Wood Duck SWMA in Stanton County where Jim Reiser had found Broad-winged Skippers (Poanes viator) back in 2007. Getting there from the north proved to be impossible as the county road bridges over the Elkhorn River were still out from last year’s flooding. So a more roundabout route from the south had to be devised and in due time we did finally arrive there to find the road through the marsh loaded with milkweeds and various other flowering plants. Thus encouraged we walked both ditches for about an hour with very few butterfly sightings of any kind, much less new “Big Year” species. Pollinators of any kind were largely absent. Eerily weird!!
So we moved on the Willow Creek SRA in Pierce county where a population of American Coppers (Lycaena phlaeas) had been discovered back in 2004. Numbers there had fluctuated over the years but they were still present last year when Steve Spomer had commented that he thought the population was in serious decline. After arriving there we scouted the trails where they had previously been found. After an hour of searching we came up empty, finding no American Coppers or many other pollinators for that matter.
So once again we moved on to the next site, Hackberry Creek SWMA in Antelope county where several marsh skippers had been found in the past. Different site – same sad story. Very few butterflies and no “Big Year” species. So we retreated to the Miller residence to speculate what could be wrong and game plan the next day.
Wednesday we made our way to a marsh on Beaver Creek in Boone county about 6 miles west of Petersburg where I had found Mulberry Wing and Broad-winged Skippers (Poanes massasoit and P. viator) back in 2001. Since that time visits by multiple individuals had produced mixed results – some years good and others with neither species being found at any population level. Our initial impression Wednesday was not good – no activity on the milkweed flowers. But after a bit of walking we noticed there were skippers flying through the vegetation in the wet ditches – double dog daring you to come out and play in the marsh on their terms. Occasionally one would get close enough to the road for you to try to net it. While the Broad winged skipper has been found at multiple locations across the state the Mulberry Wing is a different story entirely. It was reported by E. A. Dodge (from Dodge county) back in the early 1900s. After that time roughly a hundred years went by before I caught one at this location in 2001 proving the point that any fool with a net can make a contribution to science. As this was a specimen of some import it was donated it to the UNL collection for safekeeping. This remains the only known location in the state supporting a population of this butterfly. Eventually we did net/ID both skippers (I kept one Mulberry wing to replace the one I donated) and added two species to the “Big Year” list.
From there we traveled to some marshy areas in Garfield County that are the origins of the Cedar River. Primary land use in this area is hay meadows (which had already been harvested) so once again we worked the road ditches. By this point in the day the temps had reached the mid 90s and we had the ever present Nebraska gentle breeze of 25-30 mph. There was some activity on the milkweed flowers but the butterflies primary goal that day seemed to be to escape the wind and the observers. After about a half hour we netted/released a Purplish Copper (Lycaena helloides) and were thankful for that. Little (American) Coppers (Lycaena phlaeas) had been reported from this location previously and after another hour of snooping about we got a good (good enough) look at one to tally it as well. On days like today one’s ability to maintain eye contact with small objects (skippers and blues) traveling at random speeds (mostly fast) and directions against varying backgrounds is most helpful. If there is a technical term for that ability I don’t know what it is but I always wish mine was better.
Mulberry Wing Skipper – In the United States the range of this butterfly is primarily north and east of the Missouri River. In Nebraska it is known from two locations – Dodge county in the early 1900s and the Beaver Creek marsh in Boone county. It flies in a single brood in late June to mid July in marshy areas where it’s larvae feed on sedges. This skipper is listed in the NENHP rankings as a Tier 2 species (see June 14 post).
Broad-winged Skipper – Records for this marsh resident are scattered across central Nebraska north of the Platte River. Adults fly in a single mid summer brood from late June through mid July. Larvae feed on sedges or aquatic grasses. It is listed as a NENHP Tier 2 species (see June 14 post).
Purplish Copper – The Purplish Copper flies in three generations, being found from May into September. It is most common in western regions of the state, becoming more randomly distributed farther east. Although occasionally becoming numerous it is likely often overlooked due to its small size and affinity for wet areas. Larvae feed on docks (Rumex sp). This butterfly is listed as a NENHP Tier 2 species (see June 14 post).
Little (American) Copper – While this small colorful butterfly is most often found in its expected haunts (wetlands) it occasionally strays some distance from there. In Nebraska it flies in three broods and has been found from late May into mid September. Larvae feed on docks (Rumex sp.). It is an uncommon to rare species in the state and is listed as a NENHP Tier 2 species (see June 14 post).
So with the habitats being roughly equal (to my eye) my question is why such a awful day followed by an awesome one. My only hypothesis is that both Wood Duck and Hackberry Creek SWMAs are associated with the Elkhorn River and were likely subjected to last years 100 year flooding event. What happens to butterfly populations after such an extreme event? Are isolated populations eliminated? Permanently? No answers – only questions at this point. But we are thankful for the awesome Wednesday. Four new “Big Year” species – YTD total is 94.