Ixodes uriae (The seabird tick)

Abstract

The tick Ixodes uriae is a common ectoparasite of seabirds, widely distributed in circumpolar regions. It survives in bird colonies, in extremely adverse weather conditions on rocky areas free of vegetation. Currently, more than 84 bird species have been recorded as hosts, forming host-specific races independently evolving in different isolated regions. Its life cycle consists of four stages: egg, larva, nymph, and adult. Each active stage seeks a host, feeds, and then falls to the ground to develop. Males are found in nests and do not feed, while larvae, nymphs, and females are often found on their hosts. It has the widest range of thermal tolerance, from –30°C to 40°C, carrying glycerol as a cryoprotectant. Except for a short feeding period, I. uriae remains in a permanent state of cold hardiness throughout the year. This tick is an occasional parasite of some mammalian species, including humans, and it has been suggested that it may be a vector of Lyme borreliosis in marine ecosystems.