Publications

No abstract available at this time

Approximately 418,000 pounds of triazine herbicides are applied annually to control weeds in crops grown in the Albemarle-Pamilico Sound drainage basin, located in North Carolina and Virginia. An enzyme-linked immunosorbent assay was used to detect concentrations of total triazine herbicides in streams draining into Albemarle-Pamlico Sound. Water samples were collected in May and June...

The Altar Valley in southcentral Arizona was once a iallgrass prairie. Overgrazing prevented fire and spread mesquite, allowing the area, now a savanna, to be heavily used by tree-nesting raptors in summer and heavily hunted by perch-hunting raptors in winter. The breeding raptor community (over 150 pairs) consists primarily of red-tailed hawks (Buteo jamaicensis), great horned owls...

We examined the effect of progressive nutritional restriction on acid-base balance in seven captive, adult white-tailed deer (Odocoileus virginianus) from 4 February to 5 May 1988 in north central Minnesota (USA). Metabolic acidosis was indicated by low mean blood pH (7.25 to 7.33) in deer throughout the study. Mean urinary pH values declined (P = 0.020) from a mean (±SE) baseline of 8.3...

Using data from the North American Breeding Bird Survey (BBS), continental and regional changes in bird populations were estimated for the 2-year periods of 1991-1992 and 1992-1993. These 2-year changes were placed in the context of population trends since 1966. During 1991-1992, 62% of all species exhibited positive continental trend estimates. For species showing significant population...

Each spring more than 300,000 Sandhill Cranes (Grus canadensis) roost communally at night in river channels in the Platte River Valley of Nebraska and disperse at dawn to forage in agricultural fields. Cranes with central roosts had activity ranges double the size of those with peripheral roosts; 42% of the birds changed activity ranges prior to the onset of migration. Minimum daily...

Density, age-specific survival, timing of breeding and molting, and movements of the Omao or Hawaiian Thrush (Myadestes obscurus) were studied at four sites on the island of Hawaii. Mean monthly density (birds/ha) was 3.23 +- 0.57, 1.07 +- 0.33, 3.23 +- 0. 16, and 3.74 +- 0.36 at Kau Forest, Hamakua. Keauhou Ranch, and Kilauea Forest study areas, respectively. Annual survival of juvenile...

No abstract available.

Because count data collected in many bird surveys are only an index to population size, factors that can influence the counts must be identified and incorporated into analyses. Observer quality is often ignored in analyses of population changes from survey data, but observers differ in methods and capabilities and, hence, tend to count different numbers of birds. We assess the...

We studied populations of the endangered Akepa (Loxops coccineus coccineus) and Hawaii Creeper (Oreomystis mana) at four sites on the island of Hawaii. Mean monthly density (? SL) of Akepa was 5.74 t 0.87, 1.3? 0.41, 0.96 -? 0.13, and 0.76 ? 0.12 Akepa/ha at Kau Forest, Hamakua, Keauhou Ranch, and Kilauea Forest study areas, respectively. Hawaii Creepers were found at densities of 1.68...

The timing of breeding and molting was studied in six species of Hawaiian honeycreepers with differing food habits on the Island of Hawaii. The availability of nectar was highly seasonal, whereas insect abundance was relatively constant throughout the year. All six species of honeycreeper had extended breeding and molting periods with peak breeding between April and July and peak molting...

Population densities for small mammal and arthropod populations can be estimated using capture frequencies for a web of traps. A conceptually simple geometric analysis that avoid the need to estimate a point on a density function is proposed. This analysis incorporates data from the outermost rings of traps, explaining large capture frequencies in these rings rather than truncating them...