Diets of northern squawfish Ptychocheilus oregonensis, smallmouth bass Micropterus dolomieu, walleye Stizostedion vitreum, and channel catfish Ictalurus punctatus from John Day Reservoir were examined to determine the extent of predation on juvenile salmonids during seaward migrations of the salmonids during April–August 1983–1986. Juvenile Pacific salmon Oncorhynchus spp. and steelhead O. mykiss were the most important food group (by weight) of northern squawfish – about 67% – but made up smaller proportions of the food of the other predators: channel catfish, 33%; walleyes, 14%; smallmouth bass, 4%. Seasonal changes in diets indicated that northern squawfish preferred juvenile salmonids in May and August (generally the peak period of salmonid out‐migration), and switched to prickly sculpin Cottus asper when numbers of juvenile salmonids declined; walleyes and smallmouth bass showed a preference only for prickly sculpin among the prey fishes analyzed. As judged by dietary composition and prey selectivity, the northern squawfish was the major fish predator on juvenile salmonids in the reservoir; channel catfish also were important predators in the upper reservoir in spring. Walleyes and smallmouth bass were much less important predators on salmonids, and appeared to select subyearling chinook salmon only in August when the distribution of this prey overlapped with that of the predators. Size‐selective predation by northern squawfish may also play an important role in reducing survival of the smaller individuals within each run of out‐migrating juvenile salmonids.
Adult northern squawfish Ptychocheilus oregonensis, walleyes Stizostedion vitreum, smallmouth bass Micropterus dolomieu, and channel catfish Ictalurus punctatus were sampled from four regions of John Day Reservoir from April to August 1983–1986 to quantify their consumption of 13 species of prey fish, particularly seaward‐migrating juvenile Pacific salmon and steelhead (Oncorhynchus spp.). Consumption rates were estimated from field data on stomach contents and digestion rate relations determined in previous investigations. For each predator, consumption rates varied by reservoir area, month, time of day, and predator size or age. The greatest daily consumption of salmonids by northern squawfish and channel catfish (0.7 and 0.5 prey/predator) occurred in the upper end of the reservoir below McNary Dam. Greatest daily predation by walleyes (0.2 prey/predator) and smallmouth bass (0.04) occurred in the middle and lower reservoir. Consumption rates of all predators were highest in July, concurrent with maximum temperature and abundance of juvenile salmonids. Feeding by the predators tended to peak after dawn (0600–1200 hours) and near midnight (2000–2400). Northern squawfish below McNary Dam exhibited this pattern, but fed mainly in the morning hours down‐reservoir. The daily ration of total prey fish was highest for northern squawfish over 451 mm fork length (> 13.2 mg/g predator), for walleyes 201–250 mm (42.5 mg/g), for smallmouth bass 176–200 mm (30.4 mg/g), and for channel catfish 401–450 mm (17.1 mg/g). Averaged over all predator sizes and sampling months (April–August), the total daily ration (fish plus other prey) of smallmouth bass (28.7 mg/ g) was about twice that of channel catfish (12.6), northern squawfish (14.1), and walleyes (14.2). However, northern squawfish was clearly the major predator on juvenile salmonids.
We compared paired daytime and night counts of wild, resident brook trout Salvelinus fontinalis, brown trout Salmo trutta, and rainbow trout Oncorhynchus mykiss made by the same snorkelers within five stream reaches during August 1994. Reaches were 66-112 m long and had clear water, flows of 0.14-1.70 m 3 /s, and daytime water temperatures of 9-18ЊC. Each reach contained four habitat types: cascades, glides, pools, and riffles. Overall, we counted 109 trout in the daytime and 333 trout at night. Counts of trout less than 8 cm long were not different (P Ͼ 0.77), but counts of trout 8-15 cm and longer than 15 cm were higher at night than in daytime (P Ͻ 0.01 and P Ͻ 0.03, respectively). The nocturnal index for trout longer than 8 cm ranged from 58 to 100 among reaches and from 0 to 100 among habitat types. We speculate that trout counted at night were present within study reaches during the daytime but were hidden from view. Biologists should consider that trout behavior and susceptibility to observation may vary substantially between daytime and night, even during summer. In some streams, the majority of trout may not be observable during the daytime.
participants. This demonstrates evidence of the participants' learning and development of understanding and knowledge. Results Evaluations and chat box comments documented to analyse, together with reviewing patient outcome data where available. Conclusions From a response to a need in a crisis situation, this has evolved to long term collaboration between four organisations across a region, working to provide end of life care education. This will continue to improve end of life care for the patient and their families. Our evidence has shown already that these education sessions are not just required for social care but for all health care and social care professionals. Because of its success, this is now being open to all health and social care. How innovative or of interest is the abstract? Since commencing two years ago, these sessions have gathered momentum from others in health care. We have successfully gained further funding from our local commissioning group to continue this work and the eleven education sessions are funded until November. We are currently bidding for further funding to continue this great and much needed education that is now accessible to all health and social care professionals. We plan to develop the education sessions to the next level of knowledge and skills as requested by those who have attended the first sessions, it's good to see a thirst for knowledge and education towards end-of-life care.
underpinned the narratives. Nurses struggled with not being able to care for patients and their families in a way that they were used to and that felt intuitive and many described personal as well as professional affront. Conclusions Restrictions had a considerable impact on palliative care nurses at a professional and personal level in their ability to communicate with and provide care for patients and their families which led to moral distress and injury. How they managed this and made sense of what happened affected their capacity to cope, with those unable to reconcile their experiences being profoundly impacted and losing hope for the future.
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