Protein microcapsules (PM) were developed as a tool for investigating aspects of dietary protein utilization by mussels, Mytilus edulis trossulus. Digestion of PM in vitro by protease, trypsin, amylase and extracts from the gut of mussels varied significantly depending on the type of protein encapsulated or whether carbohydrates were added...
This study examined features of deep pool (>0.8 m mean depth) used by
adult summer steelhead in Steamboat Creek (1991-1992). Steamboat Creek had
a heterogenous thermal profile, with some segments exceeding preferred
temperature of steelhead. Deep pools were scarce (4% of the total habitat units)
and 39% of them were...
A static-renewal, seven day test was developed and
utilized to study the effects of nutrition on the sensitivity
of Mysidopsis intii Holmquist to zinc. It was found that
juvenile growth was the most reliable and sensitive endpoint
that could also reflect the subtle effects of low zinc
concentrations and diet...
Dietary iodine may play an important role in the nutritional health of freshwater fish larvae. Artemia, commonly used for the culture of larval zebrafish (Danio rerio), contain low concentrations of iodine when compared with wild zooplankton. Water-soluble micronutrients, such as iodine, are difficult to deliver to Artemia due to rapid...
An acceptable microparticulate diet for marine fish larvae may be defined as an artificial diet that contains, retains, and delivers the required nutrients to support survival and growth. Factors affecting ingestion rate of prey items by fish larvae include environmental factors such as light intensity, prey/background contrast, possible chemical cues,...
In the wild, marine fish larvae feed on copepods and other planktonic organisms.
Copepods are often considered the "gold standard" for meeting the nutritional needs of cultured marine fish larvae; however, in captivity, marine fish larvae are generally fed cultured live prey, i.e. rotifers (Brachionus plicatilis) and/or Artemia sp., until...
In the present study, the potential of low-melting point lipids, namely methyl palmitate (MP) and menhaden stearine (MS), were studied for delivery of water-soluble materials to fish larvae. Addition of the solid emulsifier, sorbitan monopalmitate (SMP) resulted in higher RE compared to the liquid emulsifier sorbitan sesquioleate (SSO). Additions of...
Low reproductive success has been typical of high elevation populations of the Hawaiian goose (Branta sandvicensis) or nēnē. Researchers identified predation and inadequate nutrition as limiting factors. Reproductive success remained low in most years despite on-going predator control programs. I used a supplemental feeding program over two breeding seasons in...
Greater sage-grouse (Centrocercus urophasianus) populations declined range wide during the past 50 years. Grouse populations were 2-3 times larger than the current population as recently as the early 1970's. In addition to habitat loss and fragmentation, declines were attributed habitat degradation that caused reduced productivity. Because chick survival remains the...
Index counts for the Pacific Coast race of the band-tailed pigeon (Columba fasciata monilis) have declined by -2% per year since survey efforts began in the 1950's and 60's. Mineral sites, important resources with high ion concentrations, are regularly visited by band-tailed pigeons which nest in surrounding forest lands. I...