Dr. Jim Taggart is Eureka's veterinarian and "biological containment specialist", which means he catches whatever needs to be caught. If it walks, talks, eats, breathes, or bleeds, it falls within Taggart's domain. He claims to be an Aussie and often butts heads with the sheriff and townsfolk who refuse to appreciate the delicate and unique wildlife situation in Eureka. He also gets upset when he found out that Jack Carter broke out of his hand built containment cage. Taggart knows every breed of animal, bird, and insect and he's got the tools to handle any situation. He appears to have an obsession over catching Lowjack, the dog that randomly appears all over town, and remarks that the dog is "evil incarnate" (though he does let him lick his face). He claims that Lowjack isn't "really a dog", which is hinted to be more than just an eccentric belief. Taggart is an amateur cryptozoologist which makes him one of the most knowledgeable animal specialists in Eureka.

Taggart appears to be quite fond of Jo Lupo; whether or not they share a deeper relationship is unclear ("Primal"), though he is seen making out with her in "H.O.U.S.E. Rules", and the two are seen as a couple in the possible future shown in "Once in a Lifetime". In "Phoenix Rising", Jo expresses doubts about a possible relationship with him due to their age difference. At the end of Season 1 he was 6'3" and 45 years old.

He is scheduled to appear in the second half of Eureka's third season.