Ecology of the Columbia Spotted Frog in Northeastern Oregon

Ecology of the Columbia Spotted Frog in Northeastern Oregon
Author: Evelyn L. Bull
Publisher:
Total Pages: 52
Release: 2005
Genre: Amphibian declines
ISBN:

The Columbia spotted frog (Rana luteiventris) is one of several amphibians in the Western United States experiencing population declines. The breeding, postbreeding, and overwintering habitat and ecology of this species were investigated in 10 study sites in northeastern Oregon from 1997 through 2004. A variety of habitats with permanent water were used as breeding sites and as postbreeding habitat during the summer. Ice-covered ponds, warm springs, rivers, and seeps in forested habitats were used for overwintering. Diet consisted of a wide variety of mollusks and arthropods with beetles, ants, wasps, and flies composing more than 50 percent. Population size was as high as 135 females at one site, and ratios of males to females ranged from 1.0 to 2.8. The oldest male and female were 9.7 and 8.7 years old, respectively, based on skeletochronology. Males reached sexual maturity at 1 year 9 months after metamorphosis and most females at 2 years 9 months after metamorphosis. One female laid eggs in up to 3 consecutive years. Size (snout-vent length) was not a good indicator of age in frogs older than 2 years. Long-term monitoring is necessary to determine the effects of a variety of disturbance factors and chytrid fungus that could influence spotted frog populations in northeastern Oregon.

Frogs of the United States and Canada

Frogs of the United States and Canada
Author: C. Kenneth Dodd Jr.
Publisher: JHU Press
Total Pages: 991
Release: 2023-06-20
Genre: Nature
ISBN: 1421444917

"The premiere reference book on the 108 species of frogs inhabiting North America north of Mexico. An unparalleled synthesis of the biology and behavior of all native and nonindigenous species, this two-volume, extensively referenced resource has been called the most important book ever published on North American anura. Color photographs and range maps accompany species accounts detailing information on etymology, nomenclature, identification, distribution, fossil record, systematics and geographic variation, life history and ecology, behavior, population and community biology, and conservation. This new edition of the text contains the following updates: Literature citations have been added from 2012 to 2021, now spanning from 1709 to 2021. Distribution maps have been updated, recording the decreased ranges due to declining amphibian populations. Photographs have been revised to ensure the highest digital quality. Anaxyrus williamsi and Lithobates kauffeldi, newly described species, have been included. An account is also included for Gastrophryne mazatlanensis, now recognized as occurring within the United States. Generic keys have been added. A brief section on N.A. frogs in history and art have been added. Nomenclature has been updated (Incilius for Ollotis). Now the only up-to-date and comprehensive resource for those trying to protect amphibians in the US and Canada, as well as for researchers and wildlife managers who study biodiversity"--

Amphibian Declines

Amphibian Declines
Author: Michael Lannoo
Publisher: Univ of California Press
Total Pages: 1117
Release: 2005-06-15
Genre: Science
ISBN: 0520929438

This benchmark volume documents in comprehensive detail a major environmental crisis: rapidly declining amphibian populations and the disturbing developmental problems that are increasingly prevalent within many amphibian species. Horror stories on this topic have been featured in the scientific and popular press over the past fifteen years, invariably asking what amphibian declines are telling us about the state of the environment. Are declines harbingers of devastated ecosystems or simply weird reflections of a peculiar amphibian world? This compendium—presenting new data, reviews of current literature, and comprehensive species accounts—reinforces what scientists have begun to suspect, that amphibians are a lens through which the state of the environment can be viewed more clearly. And, that the view is alarming and presages serious concerns for all life, including that of our own species. The first part of this work consists of more than fifty essays covering topics from the causes of declines to conservation, surveys and monitoring, and education. The second part consists of species accounts describing the life history and natural history of every known amphibian species in the United States.