title: Accelerated phenology of blacklegged ticks under climate warming.
abstract: The phenology of tick emergence has important implications for the transmission of tick-borne pathogens. A long lag between the emergence of tick nymphs in spring and larvae in summer should increase transmission of persistent pathogens by allowing infected nymphs to inoculate the population of naive hosts that can subsequently transmit the pathogen to larvae to complete the transmission cycle. In contrast, greater synchrony between nymphs and larvae should facilitate transmission of pathogens that do not produce long-lasting infections in hosts. Here, we use 19 years of data on blacklegged ticks attached to small-mammal hosts to quantify the relationship between climate warming and tick phenology. Warmer years through May and August were associated with a nearly three-week advance in the phenology of nymphal and larval ticks relative to colder years, with little evidence of increased synchrony. Warmer Octobers were associated with fewer larvae feeding concurrently with nymphs during the following spring. Projected warming by the 2050s is expected to advance the timing of average nymph and larva activity by 8-11 and 10-14 days, respectively. If these trends continue, climate warming should maintain or increase transmission of persistent pathogens, while it might inhibit pathogens that do not produce long-lasting infections.
authors: Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR 97331, USA Cary Institute of Ecosystem Studies, Millbrook, NY 12545, USA taal.levi@oregonstate.edu.
authors: Taal
authors: T
authors: Levi
authors: Biology Department, Bard College, Annandale-on-Hudson, NY 12504, USA.
authors: Felicia
authors: F
authors: Keesing
authors: Cary Institute of Ecosystem Studies, Millbrook, NY 12545, USA.
authors: Kelly
authors: K
authors: Oggenfuss
authors: Cary Institute of Ecosystem Studies, Millbrook, NY 12545, USA.
authors: Richard S
authors: RS
authors: Ostfeld
mesh_terms: D000818:Animals; D057231:Climate Change; D004197:Disease Reservoirs; D018884:Ixodes / Q000254:growth & development* / Q000502:physiology; D007814:Larva / Q000254:growth & development; D009758:Nymph / Q000254:growth & development; D011157:Population Dynamics; D012621:Seasons; D013997:Time Factors
keywords: Ixodes scapularis; Lyme disease; Powassan virus; anaplasmosis; phenological mismatch