Blacklegged ticks or deer ticks, the potential vectors for Lyme disease, measure up to one-eighth of an inch and are black and dark red in color, says Animal Diversity Web. Lyme disease results from a bacteria transmitted by the ticks, reports WebMD.
There are two species of ticks, the eastern and western blacklegged ticks, that are capable of carrying Lyme disease, says the Centers for Disease Control. The eastern blacklegged or deer tick, Ixodes scapularis, is native to the northeastern and north midwestern United States while the western blacklegged tick, Ixodes pacificus, resides along the west coast of the United States, from Washington to southern California. Geography is a good tool for identifying the two species, as they are very similar in appearance. In female deer ticks, the head and dorsal shield, the area immediately behind the head, are black, while the rest of the body is dark red, according to Animal Diversity Web. Male deer ticks are uniformly dark brown or black. Young ticks, or nymphs, also have a dark head, but the body is translucent. Deer tick nymphs are tiny, measuring just over one-thirtieth of an inch long. Adults are roughly one-eighth of an inch in length.
Blacklegged ticks are often present in areas with a high deer population, says Animal Diversity Web. They do not thrive at elevations above 574 feet, no matter the deer population, and do best in humid climates.