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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: 3743

Fire and the Miocene expansion of C4 grasslands Fire and the Miocene expansion of C4 grasslands

C4 photosynthesis had a mid-Tertiary origin that was tied to declining atmospheric CO2, but C4-dominated grasslands did not appear until late Tertiary. According to the ‘CO2-threshold’ model, these C4 grasslands owe their origin to a further late Miocene decline in CO2 that gave C4 grasses a photosynthetic advantage. This model is most appropriate for explaining replacement of C3...
Authors
Jon E. Keeley, Philip W. Rundel

Rana muscosa Camp 1917, Mountain Yellow-legged Frog Rana muscosa Camp 1917, Mountain Yellow-legged Frog

No abstract available at this time
Authors
Vance Vredenburg, Gary M. Fellers, Carlos Davidson

Puncture-ejection of own egg by Least Bell's Vireo and potential implications for anti-parasitism defense Puncture-ejection of own egg by Least Bell's Vireo and potential implications for anti-parasitism defense

A simple, papillary cystic adenocarcinoma of the mammary gland with metastases to the internal iliac and mesenteric lymph nodes, liver, and spleen was observed in a 12 to 13 year old female black-footed ferret (Mustela nigripes). Histologically, the tumor was aggressive, and lymphatic invasion was found. Attempts at virus isolation were negative. Other findings were bilateral infarcts in...
Authors
Bryan L. Sharp, Bonnie L. Peterson, Barbara E. Kus

Plot shape effects on plant species diversity measurements Plot shape effects on plant species diversity measurements

Abstract. Question: Do rectangular sample plots record more plant species than square plots as suggested by both empirical and theoretical studies? Location: Grasslands, shrublands and forests in the Mediterranean-climate region of California, USA. Methods: We compared three 0.1-ha sampling designs that differed in the shape and dispersion of 1-m2 and 100-m2 nested subplots. We...
Authors
Jon E. Keeley, C. J. Fotheringham

Factors affecting plant diversity during postfire recovery and succession of mediterranean-climate shrublands in California, USA Factors affecting plant diversity during postfire recovery and succession of mediterranean-climate shrublands in California, USA

Plant community diversity, measured as species richness, is typically highest in the early post-fire years in California shrublands. However, this generalization is overly simplistic and the present study demonstrates that diversity is determined by a complex of temporal and spatial effects. Ninety sites distributed across southern California were studied for 5 years after a series of...
Authors
Jon E. Keeley, C. J. Fotheringham, Melanie Baer-Keeley

Exposing extinction risk analysis to pathogens: Is disease just another form of density dependence? Exposing extinction risk analysis to pathogens: Is disease just another form of density dependence?

In the United States and several other countries, the development of population viability analyses (PVA) is a legal requirement of any species survival plan developed for threatened and endangered species. Despite the importance of pathogens in natural populations, little attention has been given to host-pathogen dynamics in PVA. To study the effect of infectious pathogens on extinction...
Authors
Leah R. Gerber, Hamish McCallum, Kevin D. Lafferty, John L. Sabo, Andy Dobson

Geographical variation of St. Lucia Parrot flight vocalizations Geographical variation of St. Lucia Parrot flight vocalizations

Parrots are vocal learners and many species of parrots are capable of learning new calls, even as adults. This capability gives parrots the potential to develop communication systems that can vary dramatically over space. St. Lucia Parrot (Amazona versicolor) flight vocalizations were examined for geographic variation between four different sites on the island of St. Lucia...
Authors
Patrick M. Kleeman, James D. Gilardi

Fire management impacts on invasive plant species in the western United States Fire management impacts on invasive plant species in the western United States

Fire management practices affect alien plant invasions in diverse ways. I considered the impact of six fire management practices on alien invasions: fire suppression, forest fuel reduction, prescription burning in crown-fire ecosystems, fuel breaks, targeting of noxious aliens, and postfire rehabilitation. Most western United States forests have had fire successfully excluded for...
Authors
Jon E. Keeley
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