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Population Biology Commons

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Full-Text Articles in Population Biology

Holocene Rice Rats (Genus Oryzomys) From The Upper Mississippi River Drainage Basin, Hugh H. Genoways Jul 2023

Holocene Rice Rats (Genus Oryzomys) From The Upper Mississippi River Drainage Basin, Hugh H. Genoways

Zea E-Books Collection

The expansion and collapse of the geographic range of the Texas rice rat (Oryzomys texensis) in the upper Mississippi River drainage basin at the end of the Holocene was a unique event in North American mammals. In a period of about 4000 years with a point of origin near the American Bottom in Illinois, these small rodents extended their geographic range in a straight-line distance of over 950 km to the west into Nebraska and the same distance to the east into Pennsylvania. Then in less than 400 years this range expansion collapsed back to a point where …


Swans: Their Biology And Natural History, Paul A. Johnsgard Feb 2016

Swans: Their Biology And Natural History, Paul A. Johnsgard

Zea E-Books Collection

The seven species of swans of the world are an easily and universally recognized group of waterfowl, which have historically played important roles in the folklore, myths and legends in many of the world’s cultures. Among the largest of all flying birds, they have also almost universally been used as symbols of royalty, grace and beauty, and largely for these reasons swans have only rarely been considered acceptable as targets for sport hunting. Swans occur on all the continents except Africa, although most species are associated with the temperate and arctic zones of North America and Eurasia. Among birds, swans …


Global Warming And Population Responses Among Great Plains Birds, Paul A. Johnsgard Feb 2015

Global Warming And Population Responses Among Great Plains Birds, Paul A. Johnsgard

Zea E-Books Collection

Based on an analysis of 47 years (1967–2014) of Audubon Christmas Bird Counts (CBC), evidence for population changes and shifts in early winter (late December) ranges of nearly 150 species of birds in the Great Plains states is summarized, a region defined as including the Dakotas, Nebraska, Kansas, Oklahoma, and the Texas panhandle. The rationale for this study had its origins in Terry Root’s 1988 Atlas of North American Wintering Birds. Root’s landmark study provided a baseline for evaluating the nationwide winter distributions of 253 North American birds in the mid-20th century, using data from the National Audubon Society’s …