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Populations of Atlantic salmon Salmo salar have experienced precipitous declines in abundance since the 1970s. This decline has been associated with reduced numbers of adult salmon returning to freshwater from their marine migration, i.e., their marine return rates (MRR). Thus, understanding the factors that affect MRR is of crucial conservation importance. We used a state-space model with a 13-year time series of individually tagged salmon mark-recapture histories on the River Frome, southern England, to test the effect of smolt body length on their MRR. As well as smolt length, the model tested for the influence of environmental covariates that were representative of the conditions experienced by the smolts in the early stages of their seaward migration, i.e., from the lower river to the estuary exit. The model indicated that, even when accounting for environmental covariates, smolt body length was an important predictor of MRR. While larger smolts have a higher probability of returning to their natal river as adults than smaller smolts, and one-sea-winter salmon have a survival rate twice as high as multi-sea-winter salmon, the actual biological mechanisms underpinning this phenomenon remain uncertain. These results have important applications for salmon conservation, as efforts to bolster salmon populations in the freshwater environment should consider ways to improve smolt quality (i.e., body size) as well as smolt quantity.

Populations of Atlantic salmon Salmo salar have experienced precipitous declines in abundance since the 1970s. This decline has been associated with reduced numbers of adult salmon returning to freshwater from their marine migration, i.e., their marine return rates (MRR). Thus, understanding the factors that affect MRR is of crucial conservation importance. We used a state-space model with a 13-year time series of individually tagged salmon mark-recapture histories on the River Frome, southern England, to test the effect of smolt body length on their MRR. As well as smolt length, the model tested for the influence of environmental covariates that were representative of the conditions experienced by the smolts in the early stages of their seaward migration, i.e., from the lower river to the estuary exit. The model indicated that, even when accounting for environmental covariates, smolt body length was an important predictor of MRR. While larger smolts have a higher probability of returning to their natal river as adults than smaller smolts, and one-sea-winter salmon have a survival rate twice as high as multi-sea-winter salmon, the actual biological mechanisms underpinning this phenomenon remain uncertain. These results have important applications for salmon conservation, as efforts to bolster salmon populations in the freshwater environment should consider ways to improve smolt quality (i.e., body size) as well as smolt quantity.

Wild Atlantic salmon, Salmo salar L., juveniles defend territories to enable exclusive access to food resources, and kin selection benefits may be accrued where territorial boundaries of relatives overlap. This study explored space sharing events between pairs of sibling and non-sibling fish as a measure of territoriality and resource competition in a small chalk stream using passive integrated transponder (PIT) technology. The time period between fish detections in a shared space was closer between pairs of siblings (sibling pairs mean = 60.48 ± 51.84 min; non-sibling pairs mean = 348.8 ±65.94 min). These results suggest that the territorial boundaries of related fish often overlap, thus increasing the likelihood of siblings accruing kin selection benefits. The findings from this study also suggest that outcomes of competitive interactions among dominant and subordinate fish are less pronounced when fish are related.

Wild Atlantic salmon, Salmo salar L., juveniles defend territories to enable exclusive access to food resources, and kin selection benefits may be accrued where territorial boundaries of relatives overlap. This study explored space sharing events between pairs of sibling and non-sibling fish as a measure of territoriality and resource competition in a small chalk stream using passive integrated transponder (PIT) technology. The time period between fish detections in a shared space was closer between pairs of siblings (sibling pairs mean = 60.48 ± 51.84 min; non-sibling pairs mean = 348.8 ±65.94 min). These results suggest that the territorial boundaries of related fish often overlap, thus increasing the likelihood of siblings accruing kin selection benefits. The findings from this study also suggest that outcomes of competitive interactions among dominant and subordinate fish are less pronounced when fish are related.

Growth is a key life-history trait in fish that is influenced by both abiotic (such as temperature and water chemistry) and biotic factors (such as density and food availability). Investigating how growth performance is influenced by such factors in the wild is important for understanding how population processes influence animals in natural environments and for predicting the response to conservation and management strategies that manipulate these conditions. The theory of kin selection predicts that significant growth and survival benefits are conferred upon animals associating with close relatives. However, resource competition may be more intense among close relatives, and little is known about the trade-off between these two processes under different ecological conditions. Here, we examine the correlation between naturally occurring densities and kin-biased growth rate using a species where kin recognition has a strong impact on behaviour in laboratory studies, but where, paradoxically, field investigations have failed to document predicted kin-biased growth or survival. Intra- and inter-family differences in growth rate of juvenile Atlantic salmon Salmo salar were studied to examine how relatedness (groups of full-sibling fish and groups of mixed-sibling fish) and sibling group (family/genotype) affect salmon parr growth, and the correlation of growth rate under a range of naturally occurring densities. Parentage and relatedness of neighbouring fish were assigned using microsatellite and passive integrated transponder tags, which allowed the growth estimation of individual fish. The results show that growth rate was significantly influenced by both sibling group (family of origin) and also by an interaction between relatedness and density. The latter finding indicates that at higher densities, full-sibling groups achieved higher growth rates in comparison to mixed-sibling groups. Thus, the growth benefits of associating with relatives are not conferred under a

Growth is a key life-history trait in fish that is influenced by both abiotic (such as temperature and water chemistry) and biotic factors (such as density and food availability). Investigating how growth performance is influenced by such factors in the wild is important for understanding how population processes influence animals in natural environments and for predicting the response to conservation and management strategies that manipulate these conditions. The theory of kin selection predicts that significant growth and survival benefits are conferred upon animals associating with close relatives. However, resource competition may be more intense among close relatives, and little is known about the trade-off between these two processes under different ecological conditions. Here, we examine the correlation between naturally occurring densities and kin-biased growth rate using a species where kin recognition has a strong impact on behaviour in laboratory studies, but where, paradoxically, field investigations have failed to document predicted kin-biased growth or survival. Intra- and inter-family differences in growth rate of juvenile Atlantic salmon Salmo salar were studied to examine how relatedness (groups of full-sibling fish and groups of mixed-sibling fish) and sibling group (family/genotype) affect salmon parr growth, and the correlation of growth rate under a range of naturally occurring densities. Parentage and relatedness of neighbouring fish were assigned using microsatellite and passive integrated transponder tags, which allowed the growth estimation of individual fish. The results show that growth rate was significantly influenced by both sibling group (family of origin) and also by an interaction between relatedness and density. The latter finding indicates that at higher densities, full-sibling groups achieved higher growth rates in comparison to mixed-sibling groups. Thus, the growth benefits of associating with relatives are not conferred under a

The use of passive integrated transponder technology facilitated the first observations of the autumn migration of 0+ year Atlantic salmon Salmo salar parr into tidal rearing habitats in the U.K. The quality of these habitats in relation to smolt production and the ecological significance of this alternative life-history strategy are presently not understood.

The use of passive integrated transponder technology facilitated the first observations of the autumn migration of 0+ year Atlantic salmon Salmo salar parr into tidal rearing habitats in the U.K. The quality of these habitats in relation to smolt production and the ecological significance of this alternative life-history strategy are presently not understood.

Li2Ti3O7 or Li2O.3TiO2 is used to recover lithium from aluminium-lithium alloys. X-ray diffraction measurements show a phase change from orthorhombic to hexagonal structure during the scavenging process, due to the incorporation of Li in the matrix and the effect of temperature. Electrodeposition of Li from the compound does not cause the structure to revert to the orthorhombic phase. Both phases have a similar scavenging capacity for Li., Li2Ti3O7 or Li2O.3TiO2 is used to recover lithium from aluminium-lithium alloys. X-ray diffraction measurements show a phase change from orthorhombic to hexagonal structure during the scavenging process, due to the incorporation of Li in the matrix and the effect of temperature. Electrodeposition of Li from the compound does not cause the structure to revert to the orthorhombic phase. Both phases have a similar scavenging capacity for Li.

Laboratory and field corrosion tests were carried out to find suitable materials for vessels to containing the clay-HCl process for extracting alumina. Of the 22 metals and alloys tested, the tantalum, niobium, zirconium, molybdenum, titanium and nickel based alloys appeared to possess the most promising corrosion resistance in these environments. The rates of corrosion were determined by measurements of weight loss., Laboratory and field corrosion tests were carried out to find suitable materials for vessels to containing the clay-HCl process for extracting alumina. Of the 22 metals and alloys tested, the tantalum, niobium, zirconium, molybdenum, titanium and nickel based alloys appeared to possess the most promising corrosion resistance in these environments. The rates of corrosion were determined by measurements of weight loss.

The USBM is conducting research on methods for sorting and identifying mixed metal scrap. A mechanical method for separating wrought and cast aluminium scrap and instrumental methods for identifying mixed aluminium scrap and mixed high-value scrap are reviewed. New research on spark testing and field experience in high-value scrap sorting are discussed., The USBM is conducting research on methods for sorting and identifying mixed metal scrap. A mechanical method for separating wrought and cast aluminium scrap and instrumental methods for identifying mixed aluminium scrap and mixed high-value scrap are reviewed. New research on spark testing and field experience in high-value scrap sorting are discussed.

Spark testing is the examination of the pattern of sparks that results when a metal or alloy is ground on an abrasive wheel. This technique requires experienced sorters, but research has shown that spectrophotometric methods can be used instead. The spectra of a mild steel, an HSLA steel, several stainless steels, and four nickel-base alloys have been measured. Differences in the spectra that are sufficient for identification are apparent., Spark testing is the examination of the pattern of sparks that results when a metal or alloy is ground on an abrasive wheel. This technique requires experienced sorters, but research has shown that spectrophotometric methods can be used instead. The spectra of a mild steel, an HSLA steel, several stainless steels, and four nickel-base alloys have been measured. Differences in the spectra that are sufficient for identification are apparent.

A number of available techniques for scrap sorting have been investigated by the USBM, (ie thermoelectric, spectroscopic and x-ray measurements) and a survey of these techniques is presented with data showing applications to specific scrap identification systems., A number of available techniques for scrap sorting have been investigated by the USBM, (ie thermoelectric, spectroscopic and x-ray measurements) and a survey of these techniques is presented with data showing applications to specific scrap identification systems.

The USBM has developed a computerised commodity flow model. A major attribute of this model is that it is amenable to updating as supply, demand and/or production data change. This report follows the flow of cobalt through its metallurgical and chemical applications and highlights areas where significant losses occur due to downgrading, export or disposal. The study indicates that about 4 300 000 lb of cobalt-bearing materials are lost each year, representing 24% of US domestic demand., The USBM has developed a computerised commodity flow model. A major attribute of this model is that it is amenable to updating as supply, demand and/or production data change. This report follows the flow of cobalt through its metallurgical and chemical applications and highlights areas where significant losses occur due to downgrading, export or disposal. The study indicates that about 4 300 000 lb of cobalt-bearing materials are lost each year, representing 24% of US domestic demand.

Populations of anadromous Atlantic salmon Salmo salar (‘salmon’) have decreased dramatically across much of their geographic range in recent decades. It is posited this is being driven by low marine survival, resulting in reduced adult return rates to natal rivers. We hypothesised that marine return rates (MRR) of adult salmon are positively influenced by their body lengths as seaward-migrating juveniles (‘smolts’), so larger smolts will be more likely to survive at sea and return as spawning adults to the natal river. We also suggest that the magnitude of this effect decreases with latitude, with its effect being weaker in more northerly populations. These were tested using individual capture-mark-recapture data from seven salmon populations in Western Europe spanning 13 degrees of latitude and 12 years of smolt cohorts. We used a multi-state state-space model to test whether MRR was influenced by smolt body length and latitude, and their interaction. Across the seven populations, smolt length had a significant positive effect on the probability of adult return, which was stronger in southern versus northern populations. Atlantic salmon smolt body length is thus an important indicator of their MRR, especially among populations in the warmer, southern part of their geographic range, with this having important implications for conserving declining salmon stocks. It suggests that management in their freshwater juvenile stages can increase MRR and should focus not only on the numbers of seaward-migrating juveniles, but also their individual quality, as indicated by their body length.

Recent declines in Atlantic salmon Salmo salar populations are generally attributed to factors in their marine life-phase. However, it is postulated that factors affecting their freshwater life-phase might impact their marine survival, such as the influence of body size. While larger smolts are widely hypothesized to have higher marine survival rates, empirical support remains scant, in part due to inadequate data and ambiguous statistical analyses. Here, we test the influence of smolt body size on marine return rates, a proxy for marine survival, using a 12-year dataset of 3688 smolts tagged with passive integrated transponders in the River Frome, Southern England. State-space models describe the probability of smolts surviving their marine phase to return as 1 sea-winter (1SW) or multi-sea-winter adults as a function of their length, while accounting for imperfect detection and missing data. Models predicted that larger smolts had higher return rates; the most parsimonious model included the effect of length on 1SW return rate. This prediction is concerning, as freshwater juvenile salmon are decreasing in size on the River Frome, and elsewhere. Thus, to maximize adult returns, restoration efforts should focus on freshwater life-stages, and maximize both the number and the size of emigrating smolts.