Classification of vegetation communities in which geese rear broods on the Yukon – Kuskokwim delta, Alaska

Abstract

Plant communities are described from an area on the Yukon – Kuskokwim (Y-K) delta of Alaska that is used extensively for brood rearing by three species of geese. Earlier studies identified plant species important as food for young geese, but few studies describe or quantify plant communities. We classified species presence or absence information from over 700 quadrats using a two-way indicator species analysis (TWINSPAN) and then tested for agreement of signatures on colour infrared air photos with the identified communities. Sedges were found to dominate all but the wettest and driest communities. Most of the brood-rearing area was covered by Carex ramenskii and Carex rariflora meadows, ponds, Carex mackenziei-dominated pond margins, and C. ramenskii and grass levee meadows. Our interpretation of airphotos accurately predicted vegetation community classes, which will facilitate future studies of habitat selection by geese during the time they are rearing young. The TWINSPAN classification was comparable to classifications of studies conducted elsewhere on the Y-K delta. The interpretation of air photos will enable the identification and evaluation of wetland vegetation complexes and potential goose brood-rearing areas away from our study site. Key words: air-photo interpretation, Alaska, plant communities, salt marsh, Yukon – Kuskokwim delta.