Post-breeding Grassland Bird Surveys
By Veronica Mecko
It is just before sunrise and I am walking up a long, steep hill to arrive at the start of the first transect on a privately owned grassland in northern Missouri. Such is the topography of northern Missouri, with long, rolling hills and amazing views from the tops of these hills. Small groups of Red-winged Blackbirds or a pair of Mourning Doves fly overhead and some birdsong is heard, but the diversity of species heard singing is much lower than during the breeding season. It’s post-breeding grassland bird survey time for MRBO, and since August 2 staff has doing surveys on private and public lands in the northern and southwest part of the state.
In northern Missouri, some of the grassland obligate species such as Dickcissel, Henslow’s Sparrow, Grasshopper Sparrow, Field Sparrow were still singing. Female Dickcissels were also observed carrying insects in their beaks, which indicates they are still feeding young birds, either as nestlings or fledglings.
Eastern Meadowlarks have been calling occasionally or they flush up from a ground roost, and Eastern Kingbirds are heard calling and are observed circling an area as if they are protecting a territory. No Bobolinks are singing, but now their faint “pink” calls are heard either from overhead or as the birds, now mostly in non-breeding plumage, move from perch to perch in small groups. Several Greater-Prairie Chickens were flushed up at Pawnee Prairie Conservation Area in the Grand River Grasslands.
The last few days we’ve done surveys in southwest Missouri and are hearing nearly as many Sedge Wrens and more Bell’s Vireos than in the north. Henslow’s Sparrows are abundant and several family groups of Dickcissels have been observed. A few Bobolinks have been heard calling either from a perch or flying overhead. This morning at Taberville Conservation Area, a group of about 45 Barn Swallows were flying high over a prairie field just before sunrise and at the same time in another area of the site, three Barn Owls were hunting low over a field.
The Sedge Wrens seem to be more abundant than during the breeding season in the north as well as the south. We’ve been hearing their staccato song and harsh calls on all of the properties we’ve surveyed so far. Studies on this species have found that they begin their breeding season in a more northern range and then in mid to late July, the males fly south and find new territories. The females follow shortly after and pairs re-nest and raise another brood. At Taberville Conservation Area only one Sedge Wren was heard during the breeding season but on July 20 I heard several males singing. Now two weeks later there are many males singing and females calling on this site.
This week we’re wrapping up the post-breeding surveys but will be back in the field in a couple of weeks to start fall migration grassland surveys.