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USGS · 70159401

Science foundation Chapter 5 Appendix 5.1: Case study california ridgway's rail ( Rallus obseoletus obsoletus )

Cory T. Overton·Julian Wood
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Abstract

The clapper rail ( Rallus longirostris ) recently was split into two sister groups (Chesser et al. 2014) on the basis of phylogenetic analyses (Maley and Brumfield 2013). The original grouping is now represented on the East Coast of North America by the Clapper rail ( Rallus crepitans ) and on the West Coast by the Ridgway’s rail ( Rallus obsoletus ). The California Ridgeway’s rail ( Rallus obsoletus obsoletus ; hereafter California rail) is the largest of 3 Ridgway’s rail subspecies which also include R. o. levipes (light-footed rail) and R. o. yumanensis (Yuma rail) (Eddleman and Conway 1994). The California rail is also the largest resident terrestrial vertebrate that lives solely in San Francisco Bay salt marshes. Formerly present in salt marsh along the California coast from Morro Bay to Humboldt Bay, by the early 1970s the California rail was breeding only in Elkhorn Slough and San Francisco Bay (Gill 1979). Population declines throughout the 19th and 20th centuries were attributed predominately to land conversion, development, and fragmentation of marshlands (USFWS 2013). However, exotic predators such as red fox ( Vulpes vulpes ) and Norway rat ( Rattus norvegicus ) are also implicated in population declines (USFWS 2013).

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90° N90° S · 180° W ← longitude → 180° E
Source-reported bounding extent: 36.86204269508728° to 38.44498466889473° latitude; -123.29406738281249° to -120.8551025390625° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Cory T. Overton, Julian Wood. 2015. Science foundation Chapter 5 Appendix 5.1: Case study california ridgway's rail ( Rallus obseoletus obsoletus ). https://pubs.usgs.gov/publication/70159401

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