Gray Wolf

The offspring is generally intermediate in size to both parents, being larger than a pure coyote, but smaller than a pure wolf. A study showed that of 100 coyotes collected in Maine, 22 had half or more wolf ancestry, and one was 89 percent wolf. A theory has been proposed that the large eastern coyotes in Canada are actually hybrids of the smaller western coyotes and wolves that met and mated decades ago as the coyotes moved toward New England from their earlier western ranges. These eastern coyote populations also have fewer sweat glands in their pawpads than western coyotes, but have more than wolves. Researchers in the Northeast and Canada say the population of coywolf hybrids is growing in the Northeast region. The red wolf is thought by certain scientists to be in fact a wolf/coyote hybrid rather than a unique species. Strong evidence for hybridization was found through genetic testing which showed that red wolves have only 5% of their alleles unique from either gray wolves or coyotes. Genetic distance calculations have indicated that red wolves are intermediate between coyotes and gray wolves, and that they bear great similarity to wolf/coyote hybrids in southern Quebec and Minnesota. Analyses of mitochondrial DNA showed that existing red wolf populations are predominantly coyote in origin.
Range and populations
The gray wolf was once the world's most widely distributed mammal, living north of 15°N latitude in North America and 12°N in Eurasia. Wolves tend to have difficulty adapting to human induced changes, and are often referred to as an indicator species; a species delineating an ecoregion or indicating an environmental condition such as a disease outbreak, pollution, species competition, or climate change. Wolves do not seem to be able to adapt as readily to expanding civilization the way coyotes do. While human expansion has seen an increase in the latter's numbers, it has caused a drop in those of the former.