Direct digital control is becoming quite common in the control
of industrial processes. However, due to the relatively high accuracy
of both analog and conventional digital systems for controlling the
speed of a dc motor, there has been a reluctance to try DDC for
this purpose. This thesis describes a...
Caissons are frequently used in the coastal environment for
breakwaters, jetties, seawalls, and piers. Because a satisfactory
analytical solution to a typical caisson installation has not been
developed, design of a caisson-style structure typically is either
based on physical model testing, which is expensive, or the
structure is designed as...
San Francisco Bay is a proposed relocation site for some of the Caspian terns Hydroprogne caspia currently nesting at the world's largest colony for the species in the Columbia River estuary and consuming salmonids listed under the U. S. Endangered Species Act (ESA). However, several runs of salmonids listed under...
Accurate assessment of specific mortality factors is vital to prioritize recovery actions for threatened and
endangered species. For decades, tag recovery methods have been used to estimate fish mortality due to avian
predation. Predation probabilities derived from fish tag recoveries on piscivorous waterbird colonies typically
reflect minimum estimates of predation...
Accurate assessment of specific mortality factors is vital to prioritize recovery actions for threatened and
endangered species. For decades, tag recovery methods have been used to estimate fish mortality due to avian
predation. Predation probabilities derived from fish tag recoveries on piscivorous waterbird colonies typically
reflect minimum estimates of predation...
Full Text:
97702, USA
Donald E. Lyons
Oregon Cooperative Fish and Wildlife Research Unit, Department of Fisheries
Accurate assessment of specific mortality factors is vital to prioritize recovery actions for threatened and endangered species. For decades, tag recovery methods have been used to estimate fish mortality due to avian predation. Predation probabilities derived from fish tag recoveries on piscivorous waterbird colonies typically reflect minimum estimates of predation...
We investigated colony size, productivity, and limiting factors for five piscivorous waterbird species nesting at 18 locations
on the Columbia Plateau (Washington) during 2004–2010 with emphasis on species with a history of salmonid
(Oncorhynchus spp.) depredation. Numbers of nesting Caspian terns (Hydroprogne caspia) and double-crested cormorants
(Phalacrocorax auritus) were stable...
Colony size, nesting ecology and diet of Caspian Terns (Hydroprogne caspia) were investigated in the San Francisco Bay area (SFBA) during 2003-2009 to assess the potential for conservation of the tern breeding population and possible negative effects of predation on survival of juvenile salmonids (Oncorhynchus spp.). Numbers of breeding Caspian...
We recovered passive integrated transponder (PIT) tags from nine piscivorous waterbird colonies in the Columbia River basin to evaluate avian predation on Endangered Species Act (ESA)-listed salmonid Oncorhynchus spp. populations during 2007–2010. Avian predation rates were calculated based on the percentage of PIT-tagged juvenile salmonids that were detected as passing...