Crossing the Isthmus…(Oaxaca and Chiapas, Mexico): 9 March 2009

Today we crossed the Mexican ‘waistline’ of the Isthmus of Tehuantepec, a significant geographic barrier that has encouraged speciation, and created a distinct division in avifaunas in Mexico. We spent our first few hours chasing sparrows and ground-cuckoos in some dry scrub on the northern side of the Isthmus (in Oaxaca state), getting both our main targets – the extremely localized Sumichrast’s Sparrow (see bottom photo), and the extremely sneaky Lesser Ground-cuckoo. It may not be quite a neotropical neomorphus ground-cuckoo, but it still played us for a while before succumbing to the ‘charms’ of our tape. Two great birds.

Later in the day we walked up a wet drainage on the Isthmus itself in the foothills around Arriaga, and pretty quickly Michael worked his magic with a couple of smart-dressed Rosita’s Buntings (see top photo), including a pink-and-rose male, resplendent in breeding dress. Also there was the endemic Green-fronted Hummingbird. We closed the day close to Mapastapec in Chiapas watching Yellow-naped Amazons flying overhead to roost en-masse.