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This study investigated the foraging behaviour, diving behaviour, movements and diet of lactating southern sea lions in the Falkland Islands. They appeared to be primarily nocturnal, benthic foragers hunting at depths ranging from the surf line down to 250 m, and from just off their breeding sites out to 45 km offshore. Occasional longer trips may extend foraging ranges to over 150 km from breeding sites. Attendance patterns suggest that Falklands' sea lions do not haulout simply to feed their pups. Other factors such as predation and thermoregulation may cause them to come ashore. When at sea they travelled at approximately 1 m s 71 , slower than previous studies of otariids indicated. Absence from the breeding site did not imply continuous foraging; all study animals used remote haulout sites away from their pups. Repeated use of the same areas and the short duration of foraging trips suggest that they were able to catch enough food within a fairly small foraging range. Data on diet support the suggestion that lactating sea lions are mainly benthic foragers. They take a wide range of prey species. The most common cephalopods were Loligo gahi, similar in size to those taken by the ®shery. There is therefore potential for competition between the sea lion population and the Loligo trawl ®shery. There was considerable overlap between the diet of sea lions and those of Gentoo and Magellanic penguins, which suggests that sea lions may compete with both species.

Kokanee (Oncorhynchus nerka lacustrine sockeye salmon) spawned in groundwater upwelling in the North Fork of the Payette River, Idaho. Intragravel water temperatures in groundwater‐influenced redds exceeded surface flow water temperature by 2.4–2.6°C. In redds without groundwater influence, intragravel and water column temperatures did not differ by more than 0.2°C. Although redds constructed in upwelling sites contained significantly more fine sediments (<0.83 mm) and were constructed in areas of significantly lower surface water velocities than redds not influenced by upwelling, preemergent survival of fry from redds in upwelling sites (84%) significantly exceeded that from redds in other areas (66%). Higher incubation temperatures at upwelling sites accelerated rates of development, protected embryos from freezing, and may increase survival of fry recruiting to Payette Lake.

Seasonal movements of 16 large (>400 mm total length) brown trout Salmo trutta were monitored for 216–347 d by means of radio telemetry techniques in Box Canyon Reservoir, Washington. In 1992, radio‐tagged fish moved out of the reservoir in late June when water temperatures reached 19–20°C and inhabited tributary streams containing water below 16°C. However, similar movements into tributary streams were not observed in 1993 when reservoir water temperatures were somewhat cooler. Diel tracking of fish in July–August 1992 revealed that no fish returned to the reservoir during this period, but that half returned to the reservoir following their fall spawning season. The remaining fish returned to the reservoir during high flows in March 1993. Summer residence of brown trout in Box Canyon Reservoir appears closely related to water temperatures. Brown trout survive in the reservoir by taking refuge in cooler tributary streams when summer water temperatures are high.

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