Date: 7/1/17 3:01 pm From: Joseph Neal <joeneal...> Subject: FOOT TREMBLING BY KILLDEER AND A RARE PLANT AT CENTERTON
Killdeer were the only shorebirds we saw at Craig state fish hatchery in Centerton this morning. There are still 2 good ponds with mudflats, and lots of aquatic insects available. One Killdeer was steadily feeding in the soft mud employing a technique often called foot trembling. It extended one foot and vibrated it in the very shallow water/wet mud. This stirring presumably brings aquatic invertebrates up from just below the surface. It was alternating feet as it moved along the soft mud.
In previous years, we’ve seen Piping and Semipalmated Plovers employing this same “fishing” technique at the hatchery. Perhaps this is part of the skill set that makes a plover a plover.
The hatchery dates to the 1940s because of big artesian springs that facilitated raising fish. These springs also nurture a relatively rare natural feature for the Ozarks: wetland. The wetlands around Centerton have been greatly altered, but an interesting community of native plants remains. In recognition of this, hatchery personnel have altered their mowing in several areas to protect these plants.
While we up there today, Joan Reynolds surveyed a couple of these unmowed strips. She found plants that are interesting or unusual, and one that was a real surprise: a tall (some up to 2 feet) white orchid in the genus Spiranthes. Collectively, these are called ladies’-tresses. Atlas of the Vascular Plants of Arkansas (2013) lists 11 species in this genus for Arkansas, including 7 that are known from northern Arkansas. This could be one of these 7, or something else. Like I said, wetland habitats in the Ozarks are rare, and they contain botanical gems. Joan took many photos. She will confer with botanists at Arkansas Natural Heritage Commission.
I’ve made birding trips to the hatchery since early 1980s. It amazes me that after so many years, and after so many rare and interesting birds, these trips continue to fascinate. Just as we were leaving, Joan spotted a Yellowbelly Water Snake, Nerodia erythrogaster. The subspecies in the Centerton area is N. e. transversa.