Grape growers seeking to protect their grapes from bird depredations have no economic guidelines for selecting one or more of several control alternatives. Many growers are not aware of the cost of applying the various control techniques, nor do they know how effective these techniques are in preventing damage to...
It is current practice to transport juvenile anadromous salmonids in transplantation and to help them bypass dams. Essentially nothing is known about the effects that transportation could have on the ability of the fish to outmigrate and be fit for survival in the marine environment. Procedures involved in transporation subject...
We evaluated the effects of the McNary Dam transportation system on emigrating fall and spring chinook smolts using physiological indices of stress (e.g., plasma cortisol, hepatic glycogen, leucocrit, interrenal cell nuclear diameter) and performance tests (e.g., saltwater challenge, secondary stress challenge, disease resistance). We also conducted controlled experiments in a...
From July 1985 to April 1987 the pelagic zooplankton community of Crater Lake, Oregon was studied to determine taxonomic structure, absolute and relative densities, and spatial and temporal distributional patterns. Samples were collected using vertically-towed zooplankton nets. The community structure consisted of two cladoceran and nine rotifer species, which were...
In 1976 and 1977 I examined three broad problems associated with the recruitment of young mallards, Anas platyrhynchos, in the Prairie Pothole Region of North Dakota. The three problems studied were: the effects of interspecific nest parasitism on production; the chronology and magnitude of total-brood loss during the brood-rearing period;...
Behavior of grizzly bears (Ursus arctos) toward people was
studied by examining hikers' reports of grizzly bear observations
and by intensively observing grizzlies in an area of Glacier National
Park that was heavily used by day-hikers. Of concern were the apparent
habituation of grizzly bears to people in the study...
Coho salmon smolts (Oncorhynchus kisutch) were transported at low and high densities. (12 and 120 g/L) for short and long periods (4 and 12 h). Because smolts can be transplanted directly to seawater, half of the fish in each treatment were transported to tanks containing seawater and half to tanks...