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We measured productivity and vegetation parameters of habitat quality at 16 Sharp-shinned Hawk (Accipiter striatus) nests in and near the greater Montreal area in order to evaluate nesting habitat use and its possible relationship to reproductive success in an urban setting. Mean clutch size was 4.4 and hatching success was 3.8 eggs per nest. At least one egg hatched in 11 of 16 nests (68.8%), 10 (62.5%) pairs raised young to a bandable age (≥10 days old), and 8 (50%) pairs successfully produced at least one fledgling. Immature individuals comprised 33.3% of male and 38.5% of female breeders. Mean values in the habitat assessment included nest tree height, 14.0 m; tree density, 955/ha; total canopy cover, 88.1%; coniferous cover, 39.7%; mean dbh, 17.6 cm; and distance to the nearest forest opening, 19.7 m. Sharp-shinned Hawks nested in a range of forest types, from mature conifer plantations to young, almost purely deciduous stands, and this population exhibited considerabl e flexibility with respect to most of the habitat features that we measured. Their use of older stands with more deciduous cover than those used by conspecifics elsewhere may reflect regional differences in habitat availability as well as in the abundance of competitor species. Breeding in an urbanized area does not seem to be detrimental to Sharp-shinned Hawks, as evidenced by this population's relatively large proportion of immature breeders and normal productivity, which appeared to be independent of all the assessed parameters of habitat quality., Knowledge of the habitat requirements of Sharp-shinned Hawks (Accipiter striatus) is important for understanding their nesting ecology and developing recommendations for their conservation and management. As habitat fragmentation is the [...]

From an analysis of nest site habitat data at 24 Sharp-shinned Hawk (Accipiter striatus) and 52 Cooper's Hawk (A. cooperii) nests in Wisconsin, we conclude that Cooper's Hawks tend to nest in stands with lower densities of taller and larger trees than do Sharp-shinned Hawks, and that Cooper's Hawks also tend to nest in sites with a greater proportion of hardwood cover than Sharp-shinned Hawks. Significant interspecific differences were found in combined habitat types (hardwoods, mixed conifer-hardwoods, and conifer plantations) for nest tree height and nest tree DBH (diameter at breast height); nest height; nest height relative to tree height: canopy height: canopy cover; tall shrub density: tree density; and mean DBH. Nest sites of the two species were similar in terms of understory canopy cover, ground cover, low shrub index, understory tree density, basal area, distance to nearest forest opening, and distance to water. We detected few significant intraspecific differences in nest site habitat, and these only in the Cooper's Hawk., Although the Sharp-shinned Hawk (Accipiter striatus) and the Cooper's Hawk (A. cooperii) breed sympatrically in many parts of the United States and southern Canada, their nest site habitats have been [...]

Adherence to the ideology of mental health was measured in a cluster sample of preprofessional students in four majors: psychology, social work, rehabilitation and health education. Mean inventory scores for the four groups did not differ significantly.

Offers opinions on smoking among college students. Problems caused by smoking for smokers and nonsmokers; Outcome of campaigns against smoking in the U.S.; Advice to smokers to avoid health-related problems caused by smoking.

A letter to the editor is presented in response to the article "American Classics" about a renovated 1906 Greek-style building in the May/June 1988 issue.