Detailed accounts of the spawning behavior of chum salmon (Oncorhynchus keta) and rainbow trout (Salmo gairdneri) in laboratory flumes are provided. The behavioral activities, quivering, probing, and crossing over increase in frequency as a function of time prior to spawning whereas digging remains constant or decreases slightly. Maps of digging locations and movie films suggest nest shape and current pattern are monitored by the female, allowing her to intensify her digging activity near the center of the nest. Probing appears to be a signal to the male indicating approach of oviposition and also provides information to the female regarding the shape and suitability of the nest site. The probing act is also used in the synchronization of the male and female spawning acts. Changes in velocity do not appear to markedly affect nest construction either in terms of number of digs to oviposition or in size of nest constructed. It is inferred that velocity and gravel size are important insofar as they influence the construction of a suitable nest depression. Nest sites would appear to be selected on the basis of acceleration of flow rather than velocity per se though high limits must obviously exist.

The organic phosphate pool of some Camargue sediments (South of France) was studied, after removal of inorganic phosphate, with Ca-NTA/dithionite (Fe bound phosphate) and Na-EDTA (Ca bound phosphate). The organic phosphate was divided into an acid soluble organic phosphate fraction (ASOP) and a residual organic phosphate fraction (ROP). The extraction of organic matter with 2.0 M NaOH (90 C) from ROP yielded considerable quantities of Org-P. In this extract the presence of phytate (inositol hexa phosphate) could be demonstrated using phytase to hydrolyse the phytate. Phytate was shown to account for a considerable part of organic phosphate in sediments of freshwater marsh sediments as well as in the sediment of the brackish/salt water lake 'Etang de Vaccares'. In laboratory experiments phytate was found to precipitate with all poly-valent cations tested. Furthermore, phytate was found to be strongly adsorbed onto Fe(OOH), which may explain its accumulation and its stability in sediments.Considerable quantities of ASOP were found; the chemical stucture of this pool remains unknown.Abbreviations: In this paper the standard abbreviations are used, as suggested by the editor (see page vi):chem-Xphys (inorg-Pdiss, Tot-Nsed)Additional abbreviations used: ASOP = acid soluble organic phosphate CaCO 3 ; P = calcium bound phosphateFe(OOH) P = iron bound phosphate NaOHextr-P = phosphate extracted with NaOH (90 C) after ASOP extraction.Phyt-P = phytate bound phosphate ROP = residual organic phosphate 118

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Objective-To determine the eVect of brief early exposure to cows' milk on atopy in the first 2 years of life. Design-Double blind, placebo controlled, randomised feeding intervention trial (Bokaal study). Setting-Dutch midwifery practices. Participants-1533 breast fed neonates. Intervention-Exposure to cows' milk protein (n = 758) or a protein free placebo (n = 775) during the first 3 days of life. Main outcome measures-Clinical atopic disease and any positive radioallergosorbent (RAST) tests at 1 year of age. Results-Atopic disease in the first year was found in 10.0% (cows' milk) v 9.3% (placebo) of the children, with a relative risk of 1.07; in the second year, atopic disease was found in 9.6% v 10.2%, respectively, with a relative risk of 0.94. Per protocol analysis showed similar results. Any RAST positive test was found in 9.4% (cows' milk) v 7.9% (placebo) of children, with a relative risk of 1.19. Stratified analysis for high family risk of allergy showed a doubled incidence of atopic disease but no eVect from the intervention. Conclusion-Early and brief exposure to cows' milk in breast fed children does not increase the risk of atopic disease in the first 2 years. (Arch Dis Child 1998;79:126-130)

We hypothesize that the interannual variability of the Northeast Pacific Ocean circulation affects the latitude of landfall and migration speed of adult sockeye salmon (Oncorhynchus nerka) returning to the Fraser River. The Ocean Surface Current Simulations (OSCURS) model was used to simulate the return migration paths of compass‐orientated sockeye for two years: 1982, which had a weak Alaska Gyre circulation and low Northern Diversion Rate (defined as the percentage of sockeye returning around the north end of Vancouver Island instead of the south end); and 1983, with a strong circulation and high northern diversion rate. The majority of model sockeye made landfall further north in 1983 than in 1982. The difference in landfall between 1983 and 1982 depended on the migration start position, swim speed, direction of orientation, and migration start date. The currents assisted the shoreward migration of sockeye starting from south of 55o N and impeded the migration of sockeye starting from further north. The simulation results were consistent with our hypothesis and suggest that the effects of the Northeast Pacific currents must be included in sockeye migration models. We propose a conceptual model for the prediction of the Northern Diversion Rate that includes Blackbourn's (1987) temperature‐displacement model, enhanced to include the effects of currents during the ocean phase of migration, and the use of two predictive formulas for the coastal phase of migration: the formula of Xie and Hsieh (1989) for sockeye approaching Vancouver Island directly from the ocean, and a yet‐to‐be‐developed formula for sockeye approaching from within the Coastal Downwelling Domain directly to the north of Vancouver Island.

By means of sequential extractions with Ca-NTA and EDTA, a separation was performed between Fe(OOH) z P and CaCO 3 z P in a few sediments ; the remaining fraction, considered to be organic phosphate, was quantified as well . We found that with the commonly used method of extraction with NaOH and H2S04, less Fe(OOH) z P and much more CaCO 3 z P was found than with the chelating extractants . The organic phosphate pool in live and dead algal material and in some mud samples was partly hydrolysed and therefore recovered as inorganic phosphates with classical extractions . The difference between chelating extractants and the classical ones is discussed .

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