J. Helminthol. Soc. Wash. 60(2), 1993, pp. 260-263 Research Note Helminths from Some Minnesota and Wisconsin Raptors STEPHEN J. TAFT,' KRISTINE Sucnow,2 AND MIA VAN HORN 1 Department of Biology, Museum of Natural History, University of Wisconsin-Stevens Point, Stevens Point, Wisconsin 54481, 2 College of Veterinary Medicine, 460 Veterinary Teaching Hospital, 1365 Gortner Avenue, St. Paul, Minnesota 55108, and 3 P.O. Box 24680, 3301 Gun Club Road, West Palm Beach, Florida 33416-4680 ABSTRACT: Seventy-seven hawks of 10 species (Accip- sin; Wisconsin Department of Natural Re- iter cooperii, Accipiter striatus, Accipiter gentilis, Circus sources, Madison, Wisconsin; and Fran cyaneus, Buteo lagopus, Buteo jarnaicensis, Buteo pla- Hamerstrom, Plainfield, Wisconsin. Complete typterus, Pandion haliaetus, Falco peregrinus, Falco sparverius) and 49 owls of 8 species (Bubo virginianus, necropsies were performed on all remains. Strix nebulosa, Strix varia, Aegolius acadicus, Otus asio, All helminths, other than nematodes, were Asio flammeus, Asio otus, Cryptoglaux funereus) from preserved in alcohol-formalin-acetic acid and Minnesota and Wisconsin were examined for hel- stained in Semichon's carmine, dehydrated, and minths. Echinoparyphium sp., Echinostoma trivolvis, Neodiplostomurn sp., Ribeiroia thomasi, Strigea fal- mounted in Canada balsam. Nematodes were conis (Trematoda), Capillaria sp., Cyrnae sp., and Por- cleared in glycerine alcohol and stored, or rocaecurn sp. (Nematoda) were common to both hawks mounted on slides using the double coverslip and owls. Paruterina sp. (Cestoda) was found only in method. the great-horned owl. Lyperosomum sp., Parastrigea sp. (Trematoda), Centrorhynchus spinosus (Acantho- Selected specimens in good condition were de- cephala), Contracaecum pandioni, Microtetrameres sp., posited in the University of Nebraska State Mu- Physaloptera sp., Serratospiculoides amaculata, and seum, Harold W. Manter Laboratory Collection Tetrameres sp. (Nematoda) were recovered from hawks. (HWML Coll.) as follows: HWML No. 35098, New host records include Lyperosomum sp. from the Centrorhynchus spinosus (Kaiser, 1893) Van gall bladder of a kestrel and Ribeiroia thomasi from the proventriculi of great-horned owls and red-tailed Cleave, 1924, ex Buteoplatypterus; HWML Nos. and broad-winged hawks. The only instance of pa- 35099, 35100, and 35101, Ribeiroia thomasi thology was a tissue reaction to S. amaculata in the (McMullen, 1938) Yamaguti, 1958, ex Pandion air sacs of a Cooper's hawk. haliaetus, Buteo platypterus, and Bubo virgini- KEY WORDS: hawks, owls, Minnesota, Wisconsin, Acanthocephala, Cestoda, Nematoda, Trematoda, anus, respectively; HWML No. 35102, Para- prevalence, pathology. strigea sp. ex Falco peregrinus; HWML No. 35103, Microtetrameres sp. ex Buteo lagopus; HWML No. 35546, Strigea falconis Szidal, 1928, No recent studies of helminth parasites ob- ex Buteo platypterus; HWML No. 35547, Strigea served in Minnesota and Wisconsin raptors have falconis ex Buteo jamaicensis; HWML No. 35548, been published. Chandler and Rausch (1947) and Neodiplostomurn sp. ex Buteo jamaicensis; Dubois and Rausch (1948, 1950a, b) concen- HWML No. 35549, Neodiplostomum sp. ex Ac- trated on strigeoids from the midwest. Morgan cipiter striatus; HWML No. 35550, Neodiplosto- (1943, 1946, 1948) discussed nematode para- mum sp. ex Accipiter cooperi; HWML No. 35551, sites. Rausch (1948) reported on cestode para- Strigea falconis ex Circus cyaneus; HWML No. sites from owls in North America. This paper 35552, Physaloptera sp. ex Accipiter striatus; presents information about helminths from 10 HWML No. 35553, Contracaecurn pandioni So- species of hawks and 8 species of owls obtained bolev and Sudarikow, 1939, ex Pandion haliae- from Minnesota and Wisconsin. tus; HWML No. 35554, Serratospiculoides ama- Seventy-seven hawks of 10 species and 49 owls culata Wehr, 1938, ex Accipiter cooperi; and of 8 species were examined for helminth para- HWML No. 35555, Porrocaecum sp. ex Buteo sites. Five were fresh road kills collected by the jamaicensis. authors in Wisconsin, and the remaining were Prevalences of infections and ranges of num- obtained frozen from the Raptor Center of the bers of worms found are given in Table 1 for University of Minnesota; the North woods Wild- hawks and Table 2 for owls. life Rehabilitation Center, Minocqua, Wiscon- Carcasses examined by us had usually been 260 Copyright © 2011, The Helminthological Society of Washington 261 Table 1. Prevalence of helminths in hawks from Minnesota and Wisconsin. Numbers in parentheses are ranges of worms per positive host. Goshawk (Accipiter gentilis, N = 1) was examined but found to be negative.* Red- Osprey Pere- Cooper's Sharp- Northern Rough- tailed Broad- (Pan- grine Kestrel hawk shinned Harrier legged (Buteo winged dion (Falco (Falco (Accipiter (Accipiter (Circus (Buteo jamai- (Buteo hali- pere- spar- cooperii) striatus) cyaneus) lagopus) censis) platypterus) aetus) grinus) verius) Echinoparyphium sp. ' 5/16 (1-169) Echinostoma trivolvis[ 1/11 1/16 (1) (37) Lyperosomum sp.2 l/9f (2) Neodiplostomum sp. ' 2/7 7/8 2/2 4/11 3/16 (20-39) (1-20) (3-12) (4-41) (1-5) Parastrigea sp.1 3/16 1/1 (1-6) (4) Ribeiroia thomasP 1/1 If 3/1 6f 1/1 (1) (1-27) (21) Strigea falconis ' 1/7 1/8 2/2 1/21 6/11 7/16 (6) (3) (1-9) (5) (20-87) (2-5) Centrorhynchus spinosus} 2/16 Contracaecurn pandioni'' 1/1 (4) Cyrnae sp.1 2/7 1/8 2/2 4/16 (1-2) (1) (3-31) (1-16) Microtetrameres sp.1 1/21 1/16 1/9 (29) (1) (5) Physaloptera sp.J 6/8 1/21 2/16 (3-5) (1) (4) Porrocaecum sp.1 3/7 1/8 2/21 5/11 6/16 (1-50) (5) (3) (3-5) (5-19) Serratospiculoides amaculatcf 1/7 (27) Tetrameres sp.1 1/9 (5) * Superscripts indicate location in host: 1 = intestine; 2 = gall bladder; 3 = proventriculus; 4 = stomach; 5 = air sacs. t New host records. frozen and in some cases refrozen. They exhib- dertaken in order to compare numbers of hel- ited slight to severe autolysis. Schoop et al. (1987) minths found by us to those reported by others. generally condemned the use of frozen hosts for Comparisons proved difficult for the following parasitological surveys because trematodes and reasons: only about one-half of the papers re- small cestodes are underrepresented and nema- ported parasite numbers; when numbers were todes and acanthocephalans are overrepresented. given they were often from different hosts; and The use of frozen hosts generally in poor con- some numbers reported were from helminth taxa dition made it difficult to identify parasites be- differing from ours. Numbers and kinds of par- yond the generic level. Pence et al. (1988) con- asites found in our samples of great-horned owls doned the practice with certain caveats, especially are compared to those of Ramalingam and Sam- when dealing with rare or endangered hosts. Rap- uel (1978), who also used frozen carcasses. They tors fit into this category. As a result, prevalence listed 13 genera, whereas species in 8 genera were rates in Table 1 and 2 may be low, especially in found in our study. The studies had 7 genera regard to trematodes and cestodes. A thorough and/or species in common (Capillaria, Cyrnae, search of the raptor parasite literature was un- Echinoparyphium, Echinostoma revolutum, Pa- Copyright © 2011, The Helminthological Society of Washington 262 JOURNAL OF Hit HtLMIN 1 HOLOUICAL SOCIETY Table 2. Prevalence of helminths in owls from Minnesota and Wisconsin. Numbers in parentheses are ranges of worms per positive host. Great grey (Strix nebulosa, N= 1) and Screech (Otus asio, N = 4) owls were examined and found to be negative.* Short- Long- Great-horned Barred Saw-whet eared eared Boreal (Bubo (Strix (Aegolins (Asio (Asio (Cryptoglaux virginianus) varia) acadicus) flammeus) otus) funereits) Echinoparyphium sp. ' 1/19 (67) Echinostoma frivol vis1 1/19 (8) Neodiplostomum sp.1 1/19 1/7 (7) (22) Ribeiroia thomasi2 2/1 9f (1-8) Strigea falconis1 4/19 1/7 (3-23) (1) Paruterina sp. 2/7 (7-19) Capillaria sp. ' 2/19 2/7 1/8 1/3 (5-9) (3-6) (2) (2) Cyrnae sp.2 4/19 2/7 d-8) (10-24) Porrocaecum sp.' 9/19 2/7 1/2 1/3 3/5 (1-6) (1-10) (1) (5) (2-16) * Superscripts indicate location in host: 1 = intestine; 2 = proventriculus. t New host records. ruterina, Porrocaecum, and Striged). Of the taxa Cooper's hawk and noted a similar tissue reac- in common, we report higher numbers only for tion surrounding the worms in the thoracic air the genus Strigea. The greater diversity and high- sac. Ours is the second published report of a er intensities of infection reported by them may species of this genus from a Cooper's hawk. simply reflect their sample size of 69 versus ours The greatest diversity of parasites (Table 1) of 19. observed by us was found in the broad-winged Specimens of Lyperosomum sp. were collected hawks. According to Mosher and Palmer (1988), from the gall bladder of a kestrel. Although a these hawks have some of the most diverse food new host record, it should not be considered un- habits among the raptors, feeding on inverte- usual because insects commonly make up a large brates, fish, amphibians, reptiles, birds, and part of the diet of these birds (Alcorn, 1934). mammals. Insects also serve as the second intermediate host We thank Dr. Ivan Kanev for identifying the for several members of the genus Lyperosomum. echinostomes while he was in the laboratory of Previously reported only in Cooper's hawk and Mary Hanson Pritchard at the University of Ne- ospreys, R. thomasi has now been recovered from braska State Museum and to Dr. William great-horned owls, red-tailed and broad-winged LeGrande for critically reading the manuscript. hawks, and again from an osprey. The second This research was supported in part by grants intermediate hosts of this parasite are either fish from The National Raptor Rehabilitators As- or amphibians (Beaver, 1939), indicating a broad sociation and the University of Wisconsin-Ste- food base for these birds.