Hi Danny,

Yes, that is a blister beetle.  They are common in Colorado (several dozen species live here) and, because many of them eat grasshopper eggs when they are larvae, their populations can track with grasshopper numbers.

Blister Beetle observations tend to peak in July before quickly tapering off.  In pastures, they hang out on flowering plants, and particularly alfalfa and other legumes.  

The most widely publicized cases involving blister beetles harming livestock are poisonings that occurred from processed alfalfa products--because the cantharidin (the problem chemical in the beetles) is stable, dead beetles are as problematic as live ones, and even a squashed beetle can contaminate hay.  The haying process can kill the beetles, which are then processed into the finished product with disastrous results.

For live animals in a pasture, the risk is different--it depends on the type of plants in the pasture (more grass usually means fewer beetles), to total number of beetles, and the likelihood of your animals eating enough live beetles, which are ostensibly trying to get out of the way, to cause problems.   If the number of beetles in the pasture are few and your animals are cautious grazers, the risk is probably low.  Low risk, though, is not "no risk."

The safest course of action is to keep the animals stalled until the beetles move on, in any one area this is usually a matter of a week or two, but could be longer.  

I hope this is helpful.

Cordially,

John