Assessing migration patterns in Passerina ciris using the world's bird collections as an aggregated resource

PeerJ. 2016 Apr 7:4:e1871. doi: 10.7717/peerj.1871. eCollection 2016.

Abstract

Natural history museum collections (NHCs) represent a rich and largely untapped source of data on demography and population movements. NHC specimen records can be corrected to a crude measure of collecting effort and reflect relative population densities with a method known as abundance indices. We plotted abundance index values from georeferenced NHC data in a 12-month series for the new world migratory passerine Passerina ciris across its molting and wintering range in Mexico and Central America. We illustrated a statistically significant change in abundance index values across regions and months that suggests a quasi-circular movement around its non-breeding range, and used enhanced vegetation index (EVI) analysis of remote sensing plots to demonstrate non-random association of specimen record abundance with areas of high primary productivity. We demonstrated how abundance indices from NHC specimen records can be applied to infer previously unknown migratory behavior, and be integrated with remote sensing data to provide a deeper understanding of demography and behavioral ecology across time and space.

Keywords: Abundance indices; Behavioral ecology; Demography; EVI; Mexico; Migration; Natural history museum collections; Ornithology; Population density; Remote sensing.

Grants and funding

Support for fieldwork in northwestern Mexico came from the Burke Museum Endowment for Ornithology, and grants from Hugh S. Ferguson, the Nuttall Ornithological Club, and Region 6 of the USFWS. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.