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Publications

Below is a list of WERC's peer-reviewed publications. If you are searching for a specific publication and cannot find it in this list, please contact werc_web@usgs.gov

Filter Total Items: 3724

Seed predation by yucca moths on semelparous, iteroparous and vegetatively reproducing subspecies of Yucca whipplei (Agavaceae) Seed predation by yucca moths on semelparous, iteroparous and vegetatively reproducing subspecies of Yucca whipplei (Agavaceae)

Yucca whipplei subspecies are distinguished by differences in reproduction: spp. whipplei and ssp. parishii are semelparous, flowering once and dying; ssp. caespitosa is iteroparous, producing multiple rosettes which may flower in different years; ssp. percursa has clonal reproduction from rhizomes, and ssp. intermedia is intermediate to the latter two. Seed loss due to the symbiotic...
Authors
Jon E. Keeley, Sterling C. Keeley, D. A. Ikeda

Carbon, oxygen and hydrogen isotope abundances inStylites reflect its unique physiology Carbon, oxygen and hydrogen isotope abundances inStylites reflect its unique physiology

Natural abundances of oxygen-18, carbon-14, carbon-13 and deuterium were measured inStylites andicola, a terrestrial vascular plant lacking stomates, and two terrestrial plant species having stomates that grew nearby. No substantial differences in oxygen-18 and carbon-13 abundances were observed among the three species. The deuterium concentration inStylites was much higher than in the...
Authors
Leonel d.S.L Sternberg, Michael J. DeNiro, D. McJunkin, R. Berger, Jon E. Keeley

The manatee in Haiti The manatee in Haiti

The future looks bleak for the manatee population in the waters around Haiti. Results of a survey conducted by the US Fish and Wildlife Service suggest that numbers have declined drastically over the last 50 years. The best hope for the few remaining is that the hunting expertise will vanish with the older generation.
Authors
G. B. Rathbun, C.A. Woods, J. A. Ottenwalder
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