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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, March 23, 2015

One of the longest Bobcat Research Studies has been going on since 1996 in the Santa Monica Mountains ringing Los Angeles,,,,,,,,,,,A second Study is about to commence and run concurrently just north of this region in Ventura County(Santa Barbara as a reference city)...............Just as with Pumas and Coyotes in this part of the world, the major Freeways that crisscross the region have been a limiting factor for Bobcats in their quest to spread their genes and and avoid interbreeding birth defects ...............While the open space between residential and commercial development is what Bobcats prefer to frequent, biologists have found that the "Bobs" will venture into the human altered landscapes .........Rabbits, squirrels, gophers and mice are numerous in both the natural and altered SoCal environment so the Bobcats dine wherever their "bread is buttered"..............Unlike Coyotes and Pumas that often get hit by cars, the major human induced mortlaity strike to the "Bobs" is the ingestion of rodenticide laced rabbits and rodents............The National Park Service estimates that there was a 70% crash in the Bobcat population in 2002 due to rodenticide ingestion...............While a ban on the 2nd generation of these poisons that were sold in retail stores went into effect last year in 2014, licensed exterminators can still utilize them and homeowners can still purchase other so-called first generation poisons..........Anti-rodenticide advocates have said that while the consumer ban will remove a lot of toxins from the environment, use by licensed exterminators still poses a threat........... Roughly 40 to 60 percent of the problem of the poisons comes from consumers, and 40 to 60 percent comes from the professional exterminator..............Exterminators acknowledge they do little to keep rats who eat their poisoned bait from escaping outdoors but most say the ban will be effective because they're trained to use the product "correctly"...............The hope is that licensed exterminators do not using second-generation anticoagulants near wild lands — a consideration that the average homeowner probably doesn’t take into account..........Knowing human nature and the fact that the Exterminator does not want the homeowner complaining about "the rats not being killed", one has to wonder if the Bobcats of Southern California can comeback to the levels of a deade ago

Bobcats: Living on the Urban Edge

Remote cameras placed at the openings of culverts photograph a bobcat crossing through.
National Park Service
Bobcats (Lynx rufus) are small robust cats that inhabit much of North America. They can range in color from tawny brown to reddish, and can vary in their in their degree of spotting. In southern California they weigh between 12-25lbs (5.5-11.4kg), with the males generally being about 4-7lbs larger than the females. Their tails are shorter than those of most cats, about 10in (24cm), but not absent as is sometimes thought, and their tails can often easily be seen from a distance.
Urban encroachment in the Simi hills, California from residential developments leads habitat fragmentation and loss of habitat for native wildlife.
National Park Service
We have been continuously studying and radio-tracking bobcats in the area since 1996, one of the longest bobcat studies ever. From this long term study, we have found that bobcats are still present in many of the remaining habitat fragments throughout the Simi Hills from Thousand Oaks to Calabasas and surrounding communities. Prior to 2002 they had relatively high survival rates in these areas. Bobcats mainly reside in the natural areas, although some individuals will visit the surrounding neighborhoods occasionally and a few will do so frequently. This may be in part due to animals passing through residential areas attempting to link habitat fragment together that on their own have become too small to support a bobcat home range. However the lush landscapes of residential areas also attract many types of smaller animals which provide a great food source for bobcats. Bobcats are strict carnivores. We have found through scat studies that bobcats in this area mainly prey on rabbits, but also consume other small animals such as woodrats, squirrels, pocket gophers, and mice, all of which can be plentiful in urban areas.
Wildlife technicians handle a bobcat kitten captured in the field.
National Park Service
Although these bobcats in our urban study area are occasionally killed by human related events such as vehicle strikes, and dog attacks, these events are relatively rare, and likely don't affect the population. However starting in the spring of 2002 we witnessed a disease epidemic in urban bobcats, and their numbers decreased dramatically in the following months and years. Animals were dying with severe infections of notoedtric mange, a disease caused by microscopic mites in the skin.
 Since 2002, more than 30 collared bobcats have died with mange infections. In addition to having mange disease, all of these individuals also tested positive for exposure to the anticoagulant chemicals commonly found in some types of rodenticides (rat poisons), and most of them had relatively high levels of the compounds. Bobcats generally do not die directly from these poisons, but rather tend to ingest sub-lethal levels of the chemicals, which over time may make them more susceptible to other diseases. Further evidence of the impact of this mange disease epidemic has been seen in our scat surveys. Bobcat scats are counted and collected monthly along specific trails and fire roads. By the fall of 2002, the number of bobcat scats collected dropped by about 70%, indicating a steep decline in the bobcat populations of the area. The number of scats has remained low since this time. Research is still being conducted to determine exactly how exposure to anticoagulant chemicals increases an individual's susceptibility to mange, but current data suggests there is a high correlation between anticoagulant exposure and severe mange infections eventually resulting in death.
To prevent secondary poisoning of bobcats and other wildlife, we suggest residents and business owners try to use other types of rodent control such as rodent-proofing buildings and food storage areas and using wooden snap traps or rat-zappers. If rodenticides must be used, avoid ones with anticoagulant chemicals such as bromadialone, difethialone, or diphacinone. Alternative rodenticides include chemicals such as zinc phosphide, which are still toxic to other animals, but thought to have fewer long-term effects.
To find out more about these wild cats, visit the following websites:

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