Strix Varia Research Articles

The Nasal Mites of Birds from Louisiana. VI. New and Additional Records of Dermanyssids (Rhinonyssinae) with Description of a New Species

A new species and new host and geographic records are established for rhinonyssine nasal mites from Louisiana birds. Ptilonyssus bombycillae sp. n. is described from Bombycilla cedrorum. The new species differs from others of the genus by a combination of characters including an almost straight posterior margin of the podosomal plate, 6 pairs of small blunt-tipped dorsal opisthosomal setae, entire pygidial plate, and all 3 anal setae posterior to the anal opening. Also, a new host record is established for Sternostoma hirundinis Fain from B. cedrorum. New geographic records include Rhinoecius cooremani Strandtmann from Strix varia and Tinaminyssus zenaidurae (Crossley) comb. n. from Zenaidura macroura. The systematics and host relationships of these species are briefly discussed. Continuing studies on the nasal mites of Louisiana birds have revealed a new species, Ptilonyssus bombycillae from Bombycilla cedrorum, and a new host and geographic records for several other rhinonyssine species. The materials and methods, including the designations and abbreviations used in the following description, have been outlined previously (Pence, 1972a). Genus Tinaminyssus Strandtmann and Wharton Strandtmann and Wharton, 1958, Contrib. Inst. Acar. Univ. Md. 4: 161. Synonymy: See Domrow, 1969. Tinaminyssus zenaidurae (Crossley) comb. n. Neonyssus zenaidurae Crossley, 1952, J. Parasit. 38: 386. Mesonyssus zenaidurae (Crossley) Fain and Aitken, 1967, Bull. Inst. Roy. Soc. Nat. Belg. 43: 39. Additional host record: 1 9 from Zenaidura macroura, mourning dove, Bonnet Carre Floodway, Norco, La., 13 October 1971, D.B.P.

Twenty Years of Avian Predator-Small Mammal Relationships in Missouri

Foods and predatoFprey relationships were ascertained from analyses of 4,651 pellet and stomach samples of great horned owls (Bubo virginianus) from the western prairie region of Missouri during the 20-year period, 1949 to 1968. Additional data were obtained from 70{) pellets of barred owls ( Strix varia ), 419 pellets of screech owls ( Otus asio ), 180 pellets of long-eared owls ( Asio otus ), and 513 pellets of red-tailed hawks (Buteo jamaicensis). Cottontail rabbits (Sylvilagus floridunus) and small rodents (mice and rats) were staple foods for all species. Other mammals and birds occasionally were taken in important amounts. Predator utilization of rabbits related poorly to abundance, as shown by midsummer rabbit census trends. Consumption of small rodents varied greatly from year to year. Per- centages of meadow mice (Microtus ochrogaster) and white-footed mice (Peromyscus spp.) in yearly diets showed little evidence of regularity in peak populations. Utilization of cotton rats (Sigmodon hispidus texianus) was strongly suggestive of irruptive peak populations at 8-year intervals, 1951 1959, and 1967, followed by rapid declines to very low levels. Foods of avian predators probably wili not serve as accurate measures of average prey populations, but unusually high populations of small rodents can be detected through long-term studies of food habits.

A Barred Owl Record

A Barred Owl Record

Cineradiographic studies of gastric motility in turkeys.

Cineradiographic studies of gastric motility in turkeys.

Telemetry as a Technique in the Study of Predation

Eight snowshoe hares (Lepus americanus) and five cottontail rabbits (Sylvilagus floridanus) were radio-tagged and tracked by an automatic system. Three of the hares, injured upon capture, lived an average of 2.3 days before being killed by predators. The remaining five survived for an average of at least 28.2 days. Of two uninjured rabbits killed, one was preyed upon within an hour after being disturbed; the other evaded predators for 24 days. Red foxes (Vulpes fulva) and owls probably were the main predators. Accounts of each instance of predation are given, including one in which both predator and prey were radio-tagged. The potential of telemetry for predation studies is emphasized, and suggestions are made for setting up such studies. The use of radio transmitters attached to animals for studies of movements and behavior is now a standard procedure (Lemunyan et al. 1959, Marshall et al. 1962, Cochran and Lord 1963, Cochran et al. 1965). However, little use has been made of this technique for investigating predation and other mortality factors, although mention has been made of its potential in this regard by Marshall and Kupa (1963). These authors were able to locate four predatorkilled grouse (Bonasa umbellus) and determine the type of predation in three cases. Recently McEwen and Brown (1966) used telemetry to study reactions of sharp-tailed grouse (Pedioecetes phasianellus) to insecticides. Through this technique they learned that at least three of their treated birds succumbed to predation. This paper emphasizes the potential of telemetry for predation studies and presents predation information obtained via the technique. Data were obtained from January through March, 1964, incidental to investigations of snowshoe hares and cottontail rabbits. Information on a night's movements of a red fox were contributed by Alan B. Sargeant. Besides foxes, other predators probably involved were barred owls (Strix varia), great horned owls (Bubo virginianus), and large hawks. The study was conducted in cedar (Thuja occidentalis) and alder (Alnus rugosa) swamps on the Cedar Creek Natural History Area, 30 miles north of Minneapolis, Minnesota. A snow cover of several inches existed throughout the study. W. W. Cochran designed and built the transmitters and automatic track-

First Records of the Barred Owl in Saskatchewan

First Records of the Barred Owl in Saskatchewan

Microelectrode studies on medial geniculate body of cat. II. Response to clicks.

Microelectrode studies on medial geniculate body of cat. II. Response to clicks.

Nesting of the Barred Owl (Strix varia) in Ontario

Nesting of the Barred Owl (Strix varia) in Ontario

A New Species of the Genus Centrorhynchus (Acanthocephala) from the Barred Owl

The genus Centrorhynchus is poorly represented in the North American fauna. Centrorhynchus spinosus (Kaiser, 1893) and C. californicus Millzner, 1924, are the only species so far attributed to this continent. With an apparent wealth of members of this genus in South America, as revealed by the researches of Travassos, migratory birds seem to offer opportunity for introduction of forms from that continent, but there are no records of such dispersal in the literature. In 1938, Dr. R. Harkema submitted to the senior author for identification specimens which he collected from a barred owl (Strix varia varia) taken in North Carolina. On cursory preliminary examination these seemed to conform to the general appearance of C. spinosus. A detailed study of these worms has revealed pronounced differences from any previously described species and hence they are recognized as belonging to a new species, which is here described as Centrorhynchus conspectus.

The Scream of the Northern Barred Owl

The Scream of the Northern Barred Owl

A New Species of Brachylaemus from the Barred Owl

A New Species of Brachylaemus from the Barred Owl

The Florida Barred Owl in North Carolina

The Florida Barred Owl in North Carolina

Behavior of the Barred Owl

Behavior of the Barred Owl

A New Name for the Texan Barred Owl

A New Name for the Texan Barred Owl

New North American Birds A New Barred Owl from Corpus Christi, Texas Outram Bangs The Labrador Spruce Grouse Outram Bangs A New Rail from Southern California Outram Bangs An Undescribed Clapper Rail from Georgia and East Florida William Brewster Chamæa fasciata and Its Subspecies Wilfred H. Osgood

New North American Birds A New Barred Owl from Corpus Christi, Texas Outram Bangs The Labrador Spruce Grouse Outram Bangs A New Rail from Southern California Outram Bangs An Undescribed Clapper Rail from Georgia and East Florida William Brewster Chamæa fasciata and Its Subspecies Wilfred H. Osgood

Habits of the Barred Owl

Habits of the Barred Owl