dispositive relative to disease development in the fetus, this does suggest that maternal transmission may be yet another important route of direct CWD transmission. Modern news stories and anecdotal evidence from treating physicians suggest that a human may have contracted Creutzfeldt-Jakob disease via the consumption of squirrel brains infected with CWD. Experimental transmission In addition to the cervid species in which CWD is known to naturally occur, black-tailed deer and European red deer have been demonstrated to be naturally susceptible to CWD. Other cervid species, including caribou, are also suspected to be naturally vulnerable to this disease. Many other non-cervid mammalian species have been experimentally infected with CWD, either orally or by intracerebral inoculation. These species include monkeys, sheep, cattle, prairie voles, mice, and ferrets. An experimental case study of oral transmission of CWD to reindeer shows certain reindeer breeds may be susceptible to CWD, while other subpopulations may be protective against CWD in free-ranging populations. None of the reindeer in the study showed symptoms of CWD, potentially signifying resistance to different CWD strains. Indirect Environmental transmission has been linked to contact with infected bodily fluids and tissues, as well as contact with contaminated environments. Once in the environment, CWD prions may remain infectious for many years. Thus, decomposition of diseased carcasses, infected "gut piles" from hunters who field dress their cervid harvests, and the urine, saliva, feces, and antler velvet of infected individuals that are deposited in the environment, all have the potential to create infectious environmental reservoirs of CWD. In 2013, researchers at the National Wildlife Research Center in Fort Collins, Colorado successfully inoculated white-tailed deer with the misfolded prion via the nasal passage, when the prions were mixed with clay. This was important because the prions had already been shown by 2006 to bind with sandy quartz clay minerals. One avian scavenger, the American crow, was recently evaluated as a potential vector for CWD. As CWD prions remain viable after passing through the bird's digestive tract, crows represent a possible mechanism for the creation of environmental reservoirs of CWD. Additionally, the crows' extensive geographic range presents ample opportunities for them to come in contact with CWD. This, coupled with the population density and longevity of communal roosting sites in both urban and rural locations, suggests that the fecal deposits at roosting sites may represent a CWD environmental reservoir. Conservative estimates for crows' fecal deposits at one winter