Eric Green

Hi Laurel, Sorry for the delay in responding. I had written a response, but the website didn't save it. I'll start by saying that I am not in favor of lethal control of coyotes at this time. Current research is starting to show that lethal control is either ineffective, or exacerbates the problems of nuisance animals. However, if coyote populations were to get extremely high, I might change my position. Conservation is not about individual animals, but about healthy populations and ecosystems. My current position is that homeowners and pet owners carry the onus of responsibility to prevent the spread of infected ticks potentially carried by coyotes. Preventive measures include the use of tick preventatives on pets and around homes, feeding pets indoors, making garbage cans inaccessible to wildlife, and eliminating outdoor water catchments that might attract coyotes. Regarding Dr. Ghert's statement that you quoted, I think that he was probably correct when he made the statement; however, like any good scientist, I'm betting he would change his mind with the availability of new information. Let's just assume that coyotes are dead-end hosts, as this is currently unknown and not the subject of my research. Indeed, the pathogen that causes RMSF doesn't survive well "in the environment", but it survives VERY well in ticks. Infected brown dog ticks pass on the pathogen to their offspring and retain the infection throughout all three life stages. This is well-documented in the literature. Now, let's imagine that a tick is on a coyote, and that coyote is near a house when the tick drops off to molt and find a new host or to lay eggs. The risk for that tick or its offspring to bite a dog or a human becomes higher. If the tick lays its thousands of eggs in or on a house, the population density of ticks becomes extremely high. In such cases, humans become incidental hosts for brown dog ticks and become infected with RMSF. The piece of the puzzle I am investigating is whether coyotes are contributing to the movement of ticks.

Thanks, William! We're eager to get started on the serology and be able to report results!

Thanks, Nick!

You too!

Thanks, William! I hope our research leads to the prevention of RMSF so that fewer people have to go through what you did.

Thanks, Cindy!

Thanks, Sean. I can't wait to get boots on the ground and start doing more field work!

Thanks, Nick.

Excellent questions! Ticks do abandon deceased hosts, probably due to the blood not flowing freely. I've looked at the literature and asked several veterinarians and physiologists how long it takes for ticks to abandon dead hosts. Nobody had a good answer, but the typical educated guess was minutes to hours. It doesn't take long for blood to coagulate. So, I do think that since many of the coyotes we sampled had been dead for several hours, most ticks would have abandoned the carcasses. However, I also think that the cold outdoor temperatures made it very likely that the ticks weren't active in December. Support of this hypothesis is that tick-borne diseases are more common in summer months, but this could also be an effect of human outdoor activity increasing in the summer. Our specimen collection efforts in the warmer months will allow us more time with each animal, rather than having many animals brought to us at once. We will hike to each carcass after the animals are culled, collect ticks first, and then proceed to collect skin and blood samples. The ticks will still be embedded if we have two major factors on our side: our speedy retrieval of carcasses, and warm enough weather to slow blood coagulation.