Ticks and Lice of the Black Bear, Ursus americanus Pallas, in Northern Georgia, USA, Including a New State Record for the Chewing Louse, Trichodectes euarctidos (Phthiraptera: Trichodectidae)

Ticks have previously been reported from the black bear, Ursus americanus Pallas, from California, Colorado, Florida, Georgia, Michigan, Minnesota, Montana, New York, Wisconsin and Nova Scotia [Taylor 1951, The distribution of ticks in Florida, M.S. Thesis, Univ. Florida, Gainesville; Rogers 1953, A study of the ixodid ticks of northern Florida, including the biology and life history of Ixodes scapularis Say (Ixodidae: Acarina), Ph.D. Diss., Univ. Maryland, College Park; King et al. 1960, New York Fish and Game J. 7: 99 - 111; Dodds et al. 1969, Can. J. Zool. 47:171 - 181; Jonkel and Cowan 1971, Wildl. Monogr. 27:1 - 57; Rogers 1975, J. Wildl. Dis. 11:189 - 192; Rogers and Rogers 1976, Intl. Conf. on Bear Res. and Management 3: 411 - 430; Crum 1977, Some parasites of black bears (Ursus americanus) in the southeastern United States, M.S. Thesis, Univ. Georgia, Athens; Manville 1978, J. Wildl. Dis. 14:97 - 101; Furman and Loomis 1984, Bull. Calif. Insect Surv. 25: 1 - 239; Forrester 1992, Parasites and diseases of wild mammals in Florida, Univ. Press of Florida, Gainesville, 459 p.; Yabsley et al. 2009, J. Parasitol. 95: 1125 - 1128]. In a survey of hunter-killed and road-killed black bears in northern Florida and southern Georgia, USA, Yabsley et al. (2009) reported 4 species of ixodid ticks from black bears in Georgia [Amblyomma americanum (L.) (lone star tick), Amblyomma maculatum Koch (Gulf Coast tick), Dermacentor variabilis (Say) (American dog tick) and Ixodes scapularis Say (blacklegged tick)] and 5 species in Florida [the same 4 species listed for Georgia plus Ixodes affinis Neumann (no common name)]. There are no previous reports of ticks associated with black bears in northern Georgia, USA.

The trichodectid chewing louse, Trichodectes euarctidos Hopkins, is a host-specific ectoparasite of the black bear (Price et al. (eds.) 2003, The chewing lice: world checklist and biological overview, Illinois Natural History Survey Special Pub. No. 24) and has been reported as Trichodectes pinguis euarctidos in most previous studies. This louse has been recorded from black bears in Florida, Idaho, Michigan, Minnesota, Montana, North Carolina, New York, Tennessee, Wisconsin, Ontario and British Columbia (Hopkins 1954, The Entomologist 87: 140 - 146; King et al. 1960; Jonkel and Cowan 1971; Rogers 1975; Rogers and Rogers 1976; Crum 1977; Worley et al. 1976, Intl. Conf. on Bear Res. and Management. 3: 455 - 464; Addison et al. 1978, Can. J. Zool. 56:2122 - 2126; Manville 1978; Yunker et al. 1980, J. Wildl. Dis. 16:347 - 356; Foster and Cames 1995, Florida Field Nat. 23:17 - 18; Reeves et al. 2007, Zootaxa 1392:31 - 68). We present herein the first record of this louse from Georgia.

Four black bears were examined for ectoparasites in northern Georgia from 2007 - 2009. Collection details for the 4 bears and their associated ectoparasites were as follows: (1) Adult male, Towns Co., nuisance relocation, 11 July 2007. Ectoparasites: D. variabilis (3 females); (2) Adult male, Dawson Co., legally harvested, September 2007. Ectoparasite: A. maculatum (1 female); (3) Adult female, Forsyth Co., roadkilled, 27 June 2008. Ectoparasites: D. variabilis (11 males, 6 females), and; (4) Subadult male, Gwinnett Co., roadkilled, 2 June 2009. Ectoparasites: A. americanum (11 males, 23 females, 9 nymphs), A. maculatum (3 males, 1 female), D. variabilis (6 males, 5 females), T. euarctidos (1 male, 3 females, 10 nymphs).

The latter bear was collected by Georgia Department of Natural Resources personnel and examined by TNN later that day. The lice were collected from the chest, upper front legs, and neck of the bear.

Both the eastern black bear (U. a. americanus Pallas) and the Florida black bear (U. a. floridanus Merriam) occur in Georgia. Due to their location in the state, the above 4 individuals were likely the nominate subspecies, U. a. americanus.

The 3 species of ticks we recorded from black bears in northern Georgia are all fairly common ectoparasites of carnivores or other medium or large-sized mammals in the southeastern United States (Forrester 1992; Pung et al. 1994, J. Med. Entomol. 31: 915 - 919; Wells et al. 2004, J. Entomol. Sci. 39: 426 - 432) especially during the summer/early fall when our collections were made. If black bears had been examined during winter or early spring, the blacklegged tick, I. scapularis, would have likely also been recorded. In fact, Yabsley et al. (2009) recorded these 4 species of ticks from black bears in southern Georgia. All 3 tick species we recorded from black bears in northern Georgia are known to be vectors of zoonotic pathogens, and Yabsley et al. (2009) molecularly detected Rickettsia sp. TR39 from A. americanum, Rickettsia parkeri from A. maculatum and R. montanensis from D. variabilis recovered from black bears in southern Georgia. Of these 3 rickettsiae, R. parkeri is known to be a zoonotic pathogen of humans (Sumner et al. 2007, Emerg. Inf. Dis. 13:751 - 753). In addition to these pathogens/symbiotes, A. americanum is known to be a vector of Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis, and of both Borrelia lonestari and Rickettsia amblyommii, which are putative agents of Southern Tick Associated Rash Illness (STARI) (Childs and Paddock 2003, Annu. Rev. Entomol. 48: 307 - 337; Billeter et al. 2007, Vector-Borne Zoonotic Dis. 7: 607 - 610). Further, in eastern North America, D. variabilis is the principal vector of Rickettsia ricketsii the causative agent of Rocky Mountain spotted fever (Wells et al. 2004).

Although T. euarctidos has previously been reported from black bears in 9 U.S. states and 2 Canadian provinces, our records are the first from the state of Georgia. Based on previous records from the adjoining states of Florida, North Carolina, and Tennessee, the collection of this louse from Georgia is not surprising. In fact, it is likely that T. euarctidos parasitizies the black bear throughout most or all of its range. Trichodectes euarctidos is not known to transmit any pathogens or parasites to black bears.

Voucher specimens of ticks and lice are deposited in the Ectoparasite Collections of the Department of Biology, Georgia Southern University (accession numbers L-3423 through L-3426).