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Grizzly bears, black bears, wolves, coyotes, cougars/ mountain lions,bobcats, wolverines, lynx, foxes, fishers and martens are the suite of carnivores that originally inhabited North America after the Pleistocene extinctions. This site invites research, commentary, point/counterpoint on that suite of native animals (predator and prey) that inhabited The Americas circa 1500-at the initial point of European exploration and subsequent colonization. Landscape ecology, journal accounts of explorers and frontiersmen, genetic evaluations of museum animals, peer reviewed 20th and 21st century research on various aspects of our "Wild America" as well as subjective commentary from expert and layman alike. All of the above being revealed and discussed with the underlying goal of one day seeing our Continent rewilded.....Where big enough swaths of open space exist with connective corridors to other large forest, meadow, mountain, valley, prairie, desert and chaparral wildlands.....Thereby enabling all of our historic fauna, including man, to live in a sustainable and healthy environment. - Blogger Rick

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Monday, December 3, 2012

Without really knowing, the Iowa Dept of Ntl Resources estimates that there are 1500-2000 Bobcats bottlenecked in the southern part of the state..........As bobcats enjoy a forested or mixed forest/field matrix, the extensive row crops that occupy the middle of the state north act as a roadblock to further Bobcat dispersal..............To kill 450 of 1500 seems a flawed management strategy..........Even if there are 2000 "Cats" in Iowa, knocking out 23 to 30% of the population is lowering genetic variability and limiting the ability of this animal to fulfill ecosystem services

I Iowa Bobcat Season Closed Friday, Dec 1 with 450 animals killed

By 2003, DNR staff tallied sightings, road kills and incidental captures of bobcats statewide, finding the animals to be common in southern Iowa.

Legal seasons have been established for harvesting bobcats in Iowa's two southernmost tiers of counties. There is no bobcat trapping season in Muscatine County.

In 2008, the third year of the surveys, there were 100 sightings per 1,000 hunting hours recorded. After 10 years, Andrews said, the survey will be more reliable in terms of telling the story of how the bobcat population is spreading from northern Missouri and southern Iowa.

The DNR estimates that there are 1,500-2,000 bobcats statewide.
Andrews said the habitat in Iowa, including the increase of grasslands and brush-filled reserves created by conservation programs, will allow continued growth.

"There is an increase ever so small into northeast Iowa. There is no reason to think that in 10 years there won't be sizeable numbers unless there is some disease, such as distemper, which is common in felines, that wipes out the population."

There was a time when Iowans, especially farmers, would kill bobcats before the animals could kill their chickens, hogs or young calves. Today, the threat to farm animals is significantly less because of hog and chicken confinements, Andrews said.
The modern-day biologist recognizes there is a role for predators and hopes to see the number of bobcats increase, he added.

Within Iowa, we analyzed tracking data from 23 radio-collared animals along with genetic markers from 625 individuals. Consistent with our other data on habitats, the tracking data indicated that bobcats prefer forest and grassland habitats when moving across the landscape and thus, many parts of Iowa pose a high level of "resistance" to bobcat movement (in figure to right note the sparse number of potential paths across row crop landscapes linking bobcats in southern Iowa with those in northeastern Iowa; in contrast there are lots of linkages across southern Iowa). Somewhat surprisingly we did not find that these distinct habitat preferences translated into differentiated genetic structure among individuals within Iowa. In practical terms this means that where habitat exists in Iowa bobcats have the potential to disperse and interbreed.

Bobcats in Iowa very much currently restricted to the southern tier of the state

But preference for forest and avoidance of cropland did affect how Iowa bobcat populations are genetically linked with bobcats in surrounding states. We analyzed DNA in 1447 tissue amples contributed by cooperators from 15 Midwestern states.

 We identified 6 genetic populations separated by both physical barriers (large expanses of row crop agriculture and a major waterway) and cryptic boundaries (zones of sharp changes in habitat type) (map right shows the 6 color-coded genetically identifiable populations; it also shows the areas in tan where bobcats could legally be harvested at the time of this study).

Recently-established populations in Iowa and northern Missouri, places where 30 years ago bobcats were virtually absent, were closely linked with bobcats to the southwest (eastern Kansas and southern Nebraska), but they showed little genetic input from populations to the north and east. Thus, large scale habitat fragmentation is influencing how bobcats are rebounding in the Midwest. The results at the regional scale emphsize the importance of understanding how wildlife management actions in surrounding states may impact Iowa's expanding bobcat populations, and vice versa.

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