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Jules G. Evens

Publications and source records attributed to Jules G. Evens.

2 recordsLinked to original sources
USGS2015

Case Study, California Black Rail (Laterallus jamaicensis corturniculus): Science Foundation Chapter 5, Appendix 5.1 in The Baylands and climate change: What can we do?

The Black Rail is the smallest member of the avian family Rallidae and has a wide-ranging but highly scattered distribution throughout the New World. Of five subspecies, two occur in North America—the Eastern Black Rail ( L.j. jamaicensis ) and the California Black Rail ( L.j. coturniculus ). Throughout its range, the Black Rail is a secretive inhabitant of tidal and freshwater wetlands and rarely ventures out from the cover of dense marsh vegetation. It is more likely to be heard than seen; spontaneous vocalizations tend to be concentrated in the nesting season and are much less common during the rest of the year.

California↗
USGS2009

Home range, habitat selection, and movements of California Black Rails at tidal marshes at San Francisco Bay, California

Little is known about the movements and habitat selection of California Black Rails ( Laterallus jamaicensis coturniculus ) in coastal California. We captured 130 Black Rails, of which we radio-marked 48, in tidal marshes in San Francisco Bay during 2005 and 2006. Our objective was to examine their home ranges, movements, and habitat selection to improve the species' conservation. The mean fixed-kernel home range was 0.59 ha, the mean core area was 0.14 ha. Home ranges and core areas did not differ by year or site. Males had significantly larger home ranges and core areas than did females. All sites combined, Black Rails used areas with ≥94% total vegetative cover, with perennial pickleweed ( Sarcocornia pacifica ) the dominant plant. The rails' habitat selection varied by year and site but not by sex. A multivariate analysis of variance indicated that Black Rails selected areas with pickleweed taller and denser than average, greater cover and height of alkali bulrush ( Bolboschoenus maritimus ) and common saltgrass ( Distichlis spicata ), more stems between 20 and 30 cm above the ground, maximum vegetation height, and shorter distance to refugia. On average, Black Rails moved 27.6 ±1.8 (SE) m daily and 38.4 ± 5.5 m during extreme high tides. Understanding the California Black Rail's movements, home range, and habitat use is critical for management to benefit the species.

California↗