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Artykuły w czasopismach na temat "Survival – Miscellanea – Juvenile literature"
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TÖTEMEYER, ANDRÉE-JEANNE. "Desert Survival and Wilderness Adventures Juvenile Literature for a Young Namibian Nation?" Matatu 17-18, nr 1 (26.04.1997): 119–36. http://dx.doi.org/10.1163/18757421-90000220.
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Marschall, Elizabeth A., i Larry B. Crowder. "Density-dependent survival as a function of size in juvenile salmonids in streams". Canadian Journal of Fisheries and Aquatic Sciences 52, nr 1 (1.01.1995): 136–40. http://dx.doi.org/10.1139/f95-013.
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The bioenergetic mechanism of density-dependent survival in juvenile stream salmonids was modeled using the relationship between density, food availability, and body size for a food-limited stream system. With a consumption-rate function estimated from laboratory experiments reported in the literature, we developed a function to predict maximum density of stream-resident juvenile salmonids of different sizes. This function can thus predict effective density based on both numbers and sizes of fish. Density predictions from this mechanistic function did not differ from predictions in the literature based on an empirically derived function describing the relationship between minimum territory size and body size in age-0 salmonids in streams, but it did suggest a bioenergetic mechanism for these relationships, linking size and consumption rate to the available food. Finally, we proposed a model of per capita survival rate as a function of the numbers and sizes in a cohort of stream-resident juvenile salmonids.
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Hemerik, Lia, i Chris Klok. "Conserving declining species using incomplete demographic information: what help can we expect from the use of matrix population models?" Animal Biology 56, nr 4 (2006): 519–33. http://dx.doi.org/10.1163/157075606778967865.
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AbstractDue to human activity, many species have strongly declined in number and are currently threatened with extinction. Management directed at conservation of these species can benefit from the use of simple population models such as matrix models. However, for many species, data on survival and reproduction are scarce. Therefore, we set up a general framework based on a matrix model with three parameters: reproduction, juvenile (=first year survival) and adult survival in which incomplete data can be analysed. This framework is applicable to species that can mature after their first year of life. The point in a calendar year at which the population size is determined, i.e. the census time, is varied. We discuss the differences and the similarities between matrices modelling the same population at different census times. The population growth rate and the elasticity of the survival and reproduction parameters have been determined analytically. From these we made, as a visual diagnostic tool (general framework), plots of the growth rate and the elasticity pattern and their dependence on actual values of the reproduction parameter and the juvenile and adult survival. To illustrate the use of this framework we plot and discuss literature data on survival and/or reproduction of a few bird species with a juvenile stage of one year in the light of our modelling results.
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Kanda, L. Leann, i Todd K. Fuller. "Demographic responses of Virginia opossums to limitation at their northern boundary". Canadian Journal of Zoology 82, nr 7 (1.07.2004): 1126–34. http://dx.doi.org/10.1139/z04-089.
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The precise response of a population at its distributional edge to the limiting extrinsic factor should be mediated by the demography of the species. We applied this principle to understanding the northern distributional potential of the Virginia opossum (Didelphis virginiana Kerr, 1792). We reviewed the literature for demographic data that we then used to build model populations. Juvenile over-winter survival was adjusted to determine the survival necessary for a stable population. To put the results in the context of life-history strategy and ecological niche, we built models for two other medium-sized mammals with similar distributions, the raccoon (Procyon lotor (L., 1758)) and the muskrat (Ondatra zibethicus (L., 1766)). Northern raccoon populations may sustain juvenile winter survival rates of <0.50 because adult females live to reproduce in multiple years. Muskrat juveniles may need a winter survival rate of only 0.40 in average years because reproduction is very high. In contrast, young northern opossums need a survival rate of 0.81 over winter to compensate for low prewinter survival. Raccoons and muskrats, through different life-history strategies, should be able to expand their northern distribution to the winter-induced physiological limit. However, opossum populations should fail before the average individual physiological limit is reached.
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Valkov, Iliya V., Mladen E. Ovcharov, Milan N. Mladenovski, Nikolay V. Vasilev i Iliya I. Duhlenski. "Radical Resection of Cerebellar Juvenile Pilocytic Astrocytoma - A 22-Year Survival: A Case Report". Journal of Biomedical and Clinical Research 13, nr 1 (1.09.2020): 59–62. http://dx.doi.org/10.2478/jbcr-2020-0009.
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Summary Juvenile pilocytic astrocytoma (JPA) is a low-grade glioma, a most common astrocytoma in young patients. It is a tumor with relatively well-defined margins. Pilocytic astrocytomas (PA) comprise approximately 5-6% of all gliomas. Gross total resection ensures a radical cure of patients and long-time survival. In the literature, the data on the survival rate of more than 20 years is scarce. A 5.5-year old boy with a history of 3-month complaints of headache, dizziness, and vomiting was diagnosed after CT to harbour a hypodense cerebellar tumor mass, situated in the midline-right hemisphere. The compression of the fourth ventricle resulted in rostral hydrocephalus with transependymal resorption. Within a week, a VP shunt was applied, followed by a radical Nafziger-Town operation. Gross total resection of the tumor was achieved. Profound clinical improvement was observed immediately after the operation. Postoperative CT scans, including the ones 22 years after the operation, remained practically normal. The patient is now 28-year old and is a perspective economist now. He leads a healthy working life. In general, the prognosis is excellent. If the tumor is completely removed by surgery, the chances of being “cured” are very high. Pilocytic astrocytoma has a five-year survival rate in over 96 percent in children and young adults, which is one of the highest survival rates of any brain tumor. However, there is even a small percent possibility for malignant transformation (1-4%).
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Wallner, Kent E., Michael F. Gonzales, Michael S. B. Edwards, William M. Wara i Glenn E. Sheline. "Treatment results of juvenile pilocytic astrocytoma". Journal of Neurosurgery 69, nr 2 (sierpień 1988): 171–76. http://dx.doi.org/10.3171/jns.1988.69.2.0171.
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✓ Treatment results for 36 patients with juvenile pilocytic astrocytoma treated from 1942 through 1985 at the University of California, San Francisco, were reviewed. Twenty-two tumors were located in the posterior fossa, 10 were in the hypothalamic region, and four were in the cerebral hemispheres. Twenty-eight patients were less than 18 years of age. The overall survival rate was 83% and 70% at 10 and 20 years, respectively. All 12 patients who had total tumor resection remain disease-free; only two of the 12 received postoperative irradiation. The 10- and 20-year freedom-from-progression for the 19 patients who had incomplete resection and received at least 40 Gy of postoperative irradiation was 74% and 41%, respectively. All patients who failed treatment had local recurrence. One patient developed diffuse meningeal seeding, after four local recurrences in the posterior fossa over a 23-year period. Six patients failed treatment and had a repeat biopsy at the time of recurrence or at postmortem examination, and three showed histological progression of the tumor to an anaplastic astrocytoma. Based on this study and others in the literature, a protocol has been adopted whereby patients who have total tumor resection are not treated with postoperative irradiation. Patients who have incomplete tumor resection and are older than 3 years of age are currently treated with postoperative partial-brain irradiation, to a dose of 45 to 60 Gy. In general, young children with incomplete resection are followed closely with computerized tomography or magnetic resonance imaging and are treated with chemotherapy or irradiation if tumor progression is documented.
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Knutson, Melinda G., Randy K. Hines, Larkin A. Powell, Mary A. Friberg i Gerald J. Niemi. "An Assessment of Bird Habitat Quality Using Population Growth Rates". Condor 108, nr 2 (1.05.2006): 301–14. http://dx.doi.org/10.1093/condor/108.2.301.
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Abstract Survival and reproduction directly affect population growth rate (λ), making λ a fundamental parameter for assessing habitat quality. We used field data, literature review, and a computer simulation to predict annual productivity and λ for several species of landbirds breeding in floodplain and upland forests in the Midwestern United States. We monitored 1735 nests of 27 species; 760 nests were in the uplands and 975 were in the floodplain. Each type of forest habitat (upland and floodplain) was a source habitat for some species. Despite a relatively low proportion of regional forest cover, the majority of species had stable or increasing populations in all or some habitats, including six species of conservation concern. In our search for a simple analog for λ, we found that only adult apparent survival, juvenile survival, and annual productivity were correlated with λ; daily nest survival and relative abundance estimated from point counts were not. Survival and annual productivity are among the most costly demographic parameters to measure and there does not seem to be a low-cost alternative. In addition, our literature search revealed that the demographic parameters needed to model annual productivity and λ were unavailable for several species. More collective effort across North America is needed to fill the gaps in our knowledge of demographic parameters necessary to model both annual productivity and λ. Managers can use habitat-specific predictions of annual productivity to compare habitat quality among species and habitats for purposes of evaluating management plans.
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Lyubeznova, N. V. "Dynamics of development of juvenile plants in the mountain-tundra belt of the Khibiny Mountains". Проблемы ботаники Южной Сибири и Монголии 22, nr 1 (3.07.2023): 208–12. http://dx.doi.org/10.14258/pbssm.2023040.
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Germination of seeds and survival of seedlings are important characteristics of the functioning of communities. There are few observations in the literature on the dynamics of seed germination in untouched alpine communities. Severe abiotic environmental factors characteristic of high mountains make it difficult for juvenile plants to take root, and they show high mortality in the first year of life. For 9 years (2011-2019), all juvenile plants were recorded on 5 m2 of the mountain-tundra community of the Khibiny Mountains and their further life was traced. For most plants of the alpine tundra community, low germination and high mortality of juvenile plants in the first year of life were confirmed. Seeds of some species of undisturbed plots, did not germinate during the observation period, most of the rest they did not survive. In species of slightly disturbed places, the number of seedlings was proportional to the number of species in the community, with the exception of species that do not have vegetative propagation. In the latter, seed germination was higher. A surge in the number of seedlings was observed in 2016 and 2019. The surviving individuals did not pass into the generative age state for 7-9 years of observations, which confirms the duration of the life cycle of alpine species.
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Carrasco-Rueda, Farah, i Raúl Bello. "Demographic dynamics of Peruvian black-faced spider monkeys (<i>Ateles chamek</i>) reintroduced in the Peruvian Amazon". Neotropical Primates 25, nr 1 (1.12.2019): 1–10. http://dx.doi.org/10.62015/np.2019.v25.86.
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Reintroductions of animals are important conservation tools for different taxa around the world. A reintroduction program in the Peruvian Amazon is focusing on black-faced spider monkeys (Ateles chamek). We investigated life-history parameters such as stage-specific survival and female fertility rates using a capture-mark-recapture framework and data from the literature. We estimated growth rate and probability of extinction for a reintroduced group using matrix models, as well as testing whether population growth depends more on survival of juvenile females or adult females. Our results suggest the population of the reintroduced group is decreasing. After projecting the group size for the next 25 years using different scenarios, we found that in order for the group to persist, survival rate of the female adult stage needs to exceed 79 %. Given that group growth rate is more sensitive to the survival of adult females, management measures actions that target this demographic are required to guarantee survival of the group. Extrapolations of our results are subject to restrictions imposed by the small sample size and the conditions specific to this reintroduction program. However, this study may provide valuable lessons for reintroduction programs attempting the recovery of wild populations of similar species.
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Kalantri, Siddhesh Arun, Saikat Datta, Vijaykumar Shirure, Subham Bhattacharya i Maitreyee Bhattacharyya. "Azacytidine in Juvenile Myelomonocytic Leukaemia: A Single Centre Experience". Blood 132, Supplement 1 (29.11.2018): 5524. http://dx.doi.org/10.1182/blood-2018-99-112033.
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Abstract Background Juvenile myelomonocytic leukemia (JMML) is very rare and aggressive disease of infancy and childhood. This disorder is characterized by features of both myeloproliferative and myelodysplastic disorders. Allogeneic stem cell transplant is the only curative option available for this disease. The median survival time of children who do not receive an allograft can be as short as 10 to 12 months. Recent studies have highlighted the importance of epigenetic aberrations (aberrant DNA methylation) in JMML. Hence, azacytidine an epigenetic modifier can be good potential therapeutic option in these group of patients. There are very few cases reported in literature. Rarity of this disease makes prospective randomized trials with this agent difficult. Here we report favorable outcome for three patients diagnosed with this fatal condition. Case Series Three patients diagnosed JMML as per WHO 2016 Criteria since March 2017 were enrolled in this study after obtaining informed consent. Details of baseline patient characteristics are shown in table 1. All the patients received azacytidine at 75mg/m2/ day for seven consecutive days every 28 days. All the patients have refused option of allogenic stem cell transplant and hence they are planned to be kept on same protocol till progression. Two children are continuing treatment. First patient enrolled in this study has completed 13 cycles. Second patient discontinued treatment after completion of 5 cycles of azacytidine (parental preference). Third patient in this study has completed 9 cycles. Bone marrow aspiration and cytogenetic evaluation was planned after 6 cycles of azacytidine. Results All the children enrolled in this study are maintaining stable course and are free from transfusion requirement. The second patient who discontinued therapy after 5 cycles of azacytidine is also doing well as per telephonic confirmation with parents and is free from any transfusion requirement at 14 months since he was enrolled in study. At a median follow up of 13 months since the date of diagnosis, all three children are surviving (Range 10-16 months) which is already higher than median overall survival reported for patients not receiving stem cell transplant. No patient has shown evidence of clinical progressive disease as per response criteria of JMML International Symposium (December 2013). As per these criteria one patient had clinical complete remission, another patient had clinical partial remission with progressive genetic disease and the patient who lost to follow up is considered to have clinically stable disease (since we could not complete assessment for this patient). Table 2 summarizes response to treatment for different parameters assessed. We documented a new cytogenetic abnormality (appearance of 20 q deletion) in one patient which was not documented at baseline. Therapy was well tolerated and no major toxicities (grade III-IV) were documented except episode of febrile neutropenia in one patient requiring hospitalization. Other adverse events included thrombocytopenia in between cycles but none were grade III-IV after initial platelet response. Discussion and conclusion Though the sample size is small, results are encouraging. To note all patients in our study had platelet count less than 33 thousand and two patients had haemoglobin F percentage higher than that for age which are poor prognostic clinical variable as reported by EWOG-MDS study group. Our results are similar to those reported by EWOG MDS study group which comprised of nine treatment naive patients. Azacytidine was used for bridge to transplant in this group. However, in resource poor setting like India where most families cannot afford transplant it would be prudent to evaluate if azacytidine can prolong survival or alter the natural history of this fatal disease. Long term study with more number of patients are required to know whether azacytidine can be a suitable alternative in patients where stem cell transplant is not an option. Disclosures No relevant conflicts of interest to declare.
Książki na temat "Survival – Miscellanea – Juvenile literature"
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Green, Jen. Extreme survival. Great Bardfield: Miles Kelly, 2010.
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Turner, Tracey. Jungle survival. London: Franklin Watts, 2013.
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illustrator, Smith Dave, red. Jungle survival. Hauppage, New York: Barron's, 2014.
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Chancellor, Deborah. Boy Stuff Pocket Survival Guide. Bath, UK: Parragon, 2010.
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Wood, John Norris. Survival: Could you be a mouse? Toronto: Macmillan of Canada, 1990.
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Wood, John Norris. Survival: Could you be a frog? Nashville, Tenn: Ideals Children's Books, 1990.
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Wood, John Norris. Survival: Could you be a mouse? Nashville, Tenn: Ideals Children's Books, 1990.
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Slepian, Curtis. All about survival. New York, New York: Time for Kids Books, an imprint of Time Home Entertainment, Inc., 2014.
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Ganeri, Anita. Harsh habitats. London: Raintree, 2013.
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History), British Museum (Natural, red. Can the whales be saved?: Questions about the natural world and the threats to its survival answered by the Natural History Museum. New York, N.Y., U.S.A: Viking Kestrel, 1989.
Znajdź pełny tekst źródłaCzęści książek na temat "Survival – Miscellanea – Juvenile literature"
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Tötemeyer, Andree-Jeanne. "Desert Survival and Wilderness Adventures. Juvenile Literature for a Young Namibian Nation?" W Preserving the Landscape of Imagination, 119–36. BRILL, 1997. http://dx.doi.org/10.1163/9789004656154_014.
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"Nutrients in Salmonid Ecosystems: Sustaining Production and Biodiversity". W Nutrients in Salmonid Ecosystems: Sustaining Production and Biodiversity, redaktorzy E. Eric Knudsen, Eric W. Symmes i E. Joseph Margraf. American Fisheries Society, 2003. http://dx.doi.org/10.47886/9781888569445.ch19.
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<em>Abstract.</em>—A number of Pacific salmon populations have already been lost and many others throughout the range are in various states of decline. Recent research has documented that Pacific salmon carcasses serve as a key delivery vector of marine-derived nutrients into the freshwater portions of their ecosystems. This nutrient supply plays a critical biological feedback role in salmon sustainability by supporting juvenile salmon production. We first demonstrate how nutrient feedback potential to juvenile production may be unaccounted for in spawner-recruit models of populations under long-term exploitation. We then present a heuristic, life history-based, spreadsheet survival model that incorporates salmon carcass-driven nutrient feedback to the freshwater components of the salmon ecosystem. The productivity of a hypothetical coho salmon population was simulated using rates from the literature for survival from spawner to egg, egg to fry, fry to smolt, and smolt to adult. The effects of climate variation and nutrient feedback on survival were incorporated, as were density-dependent effects of the numbers of spawners and fry on freshwater survival of eggs and juveniles. The unexploited equilibrium population was subjected to 100 years of 20, 40, 60, and 80% harvest. Each harvest scenario greater than 20% brought the population to a reduced steady state, regardless of generous compensatory survival at low population sizes. Increasing harvest reduced the positive effects of nutrient contributions to population growth. Salmon researchers should further explore this modeling approach for establishing escapement goals. Given the importance of nutrient feedback, managers should strive for generous escapements that support nutrient rebuilding, as well as egg deposition, to ensure strong future salmon production.
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"The Ecology of Juvenile Salmon in the Northeast Pacific Ocean: Regional Comparisons". W The Ecology of Juvenile Salmon in the Northeast Pacific Ocean: Regional Comparisons, redaktorzy Alex C. Wertheimer i Frank P. Thrower. American Fisheries Society, 2007. http://dx.doi.org/10.47886/9781888569957.ch9.
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Abstract.—Interannual variability in chum salmon <em>Oncorhynchus keta </em>mortality during early marine life is thought to have a major influence on recruitment. However, few estimates of daily mortality are available for chum salmon during this period, and average values reported in the literature are unrealistically high when used in a simple life-history model. We analyzed survival to adult of seven groups of chum salmon, marked as juveniles, and released at different times and sizes at Little Port Walter, Alaska to estimate average daily mortality during early marine residency for an early emigration group and a late emigration group. We assumed that differences in proportions of groups surviving to adult between the initial releases of unfed fry and subsequent releases of fed fry for each group were due to natural mortality during the time interval between releases. For both groups, mortality was highest during the period immediately after release, declining rapidly thereafter. Average daily mortality was 8.1% for the early release during their first 21d in the ocean and 3.9% for the late release during the first 32 d in the ocean. After May 4 (54 d and 33 d postrelease, respectively, for the early and late groups), average daily mortality was less than 0.6% for both groups. These results support the paradigm that most of the mortality of chum salmon in the ocean occurs early in their marine residency, and the results provide realistic rates for demographic modeling of the abundance of chum salmon in marine habitats.
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"Biology and Management of Inland Striped Bass and Hybrid Striped Bass". W Biology and Management of Inland Striped Bass and Hybrid Striped Bass, redaktorzy Wayne Gustaveson i Georg Blommer. American Fisheries Society, 2013. http://dx.doi.org/10.47886/9781934874363.ch2.
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<em>Abstract</em>.—The discovery of landlocked populations of striped bass <em>Morone saxatilis</em> in Santee–Cooper Reservoir, South Carolina and Kerr Reservoir, Virginia prompted a rush to stock striped bass in other inland waters of the United States, including impoundments in the Colorado River. Fisheries managers responsible for Colorado River waters studied existing literature and predicted that it would be unlikely for successful natural reproduction of striped bass in these systems. Striped bass population development proved unique in the Colorado River system, which is marked by nutrient-poor, well-oxygenated waters with limited forage. Natural reproduction did occur in these reservoirs despite the lack of current previously thought to be essential for successful reproduction, resulting in high survival. Developing populations were sometimes overabundant to the point of forage elimination from pelagic zones. Lack of prey limited growth and temporarily reduced reproduction. Eventually forage returned, increasing striped bass growth and maturity, which led to more reproduction (a “boom and bust”cycle). Planned low-impact, low-abundance adult trophy fisheries produced by managed stocking were replaced by high-abundance juvenile fisheries with high catch rates produced by natural reproduction. In most years, juvenile striped bass living in warm surface waters proved to have the competitive advantage over adults for limited forage.
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"Challenges for Diadromous Fishes in a Dynamic Global Environment". W Challenges for Diadromous Fishes in a Dynamic Global Environment, redaktorzy Keith H. Nislow i Boyd E. Kynard. American Fisheries Society, 2009. http://dx.doi.org/10.47886/9781934874080.ch30.
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<em>Abstract</em>.-The sea lamprey <em>Petromyzon marinus </em>is a widely distributed anadromous species spawning in coastal rivers and streams throughout the north Atlantic basin. In this paper, we review aspects of sea lamprey migration and ecology that relate to the transport of nutrients and materials to and from freshwater ecosystems and provide an example of a long-term study of a native wild population. Several aspects of lamprey life history (rapid growth in marine phase, many adults spawn in upper reaches of small oligotrophic rivers, all adults die after spawning) suggest that anadromous sea lampreys contribute marine-derived nutrients and materials (MDNM) to freshwater ecosystems. We used long-term (20 years) data on spawner abundance, along with literature-derived concentration values, to estimate the import of nutrients and materials to a spawning reach of the Fort River, a tributary of the Connecticut River in western Massachusetts, USA. Sea lamprey imported as much as 0.26 g of P per square meter of stream, as much as of 20% of the total annual P loading to a similar system where a full P budget has been developed. While the MDNM contribution of sea lamprey may be substantial, other aspects of their life history and habitat use may limit the overall magnitude and direction of lamprey influence on freshwater ecosystems. Spawning requirement for rocky substrate within a narrow size range may limit import at the watershed scale. In addition, marine survival rates of less than ~1% will result in a net export of nutrients and materials via out-migrating juveniles (transformers). While there is currently no information on survival rates in wild anadromous populations, the tight link between adult survival and prey/host fish populations observed in landlocked Great Lakes systems suggests that the ecological role of sea lamprey may be strongly related to the abundance of coastal marine fishes. Further research on adult survival, juvenile dispersal and distribution, and the paths of nutrient and material uptake in spawning streams are necessary to more fully evaluate the role of anadromous sea lamprey in the transport of MDNM.
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"Propagated Fish in Resource Management". W Propagated Fish in Resource Management, redaktorzy BARRY BEREJIKIAN, THOMAS FLAGG i PAUL KLINE. American Fisheries Society, 2004. http://dx.doi.org/10.47886/9781888569698.ch20.
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<em>Abstract.</em>—Captive broodstocks have been initiated for maintenance and recovery of imperiled anadromous salmonid populations because they can provide a rapid demographic boost and reduce short-term extinction risk. As with captive propagation programs for other vertebrates, difficulties with reintroduction to the natural environment may impede success in achieving the program’s objectives. Strategies for reintroduction of anadromous salmonid captive broodstocks in the United States and Canada include release of captively reared adults (currently four programs), stocking their offspring as eyed eggs (two programs), parr (six programs), or smolts (nine programs). Captive broodstock programs that release adults considered the management objectives of (i) evaluating of different reintroduction strategies, and (ii) spreading the risk of failure of any one particular strategy to be much more important than programs that do not release adults. This distinction indicates that the programs releasing adults consider the strategy to be an experimental one that may serve to offset potential risks associated with juvenile release options. However, the finding that preventing extinction was considered to be very important in adult and juvenile release programs alike indicates that programs releasing adults believe the strategy, at a minimum, will not impede that objective. We summarized the salmonid literature on (1) natural and sexual selection during reproduction, (2) homing and straying, (3) rearing effects on social behavior, (4) domestication, and (5) survival as it relates to biological trade-offs of different reintroduction strategies for captive broodstocks. The adult release strategy provides potential biological benefits that include the opportunity for natural and sexual selection to occur on the spawning grounds—selection that is relaxed during artificial spawning. Adult release and egg stocking may reduce potential for unnaturally high straying rates and may minimize domestication selection of the offspring compared to programs that artificially spawn adults and release their offspring as smolts. The potential benefits of adult and egg releases must be weighed against (and may be offset by) the greater F1 production that could be achieved by releasing hatchery-reared smolts. A variety of reintroduction strategies will likely continue to be appropriate for captive broodstock programs.
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"Pacific Salmon: Ecology and Management of Western Alaska’s Populations". W Pacific Salmon: Ecology and Management of Western Alaska’s Populations, redaktorzy Matthew J. Nemeth, Benjamin C. Williams, Robert C. Bocking i Simon N. Kinneen. American Fisheries Society, 2009. http://dx.doi.org/10.47886/9781934874110.ch6.
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<em>Abstract.</em>—Data were collected in Norton Sound from 2002 through 2006 to support the development of habitat-based models of coho salmon smolt production and adult escapements. Length of stream rearing habitat available to juvenile coho salmon in the summer was estimated at 83 km on the Nome River and 277 km on the North River, using a combination of <em>a priori </em>predictions of fish distribution and subsequent field sampling. The likely range of smolts produced by this habitat was modeled using three different relationships of habitat quantity and smolt production developed elsewhere. The estimated escapement of adult salmon needed to produce this range of smolts resulted in counts from 2,632 to 3,649 fish in the Nome River and from 8,766 to 10,481 fish in the North River, using various literature values of production, survival, and fecundity. A field study conducted in the next two years to estimate actual smolt abundance in the Nome River yielded estimates of 92,820 (95% CI = 84,615 – 101,026) in 2005 and 122,079 (95% CI = 112,612 – 131,546) coho salmon in 2006; these smolt abundances were within the range estimated by the <em>a priori </em>models. Through 2007, average adult coho salmon escapement to both rivers had also been within the 95% confidence interval predicted from two of the three smolt models, within 2% and 18% of the point estimate of one model, and within 27% and 32% of the second. Overall, models based on production estimates and life history variables developed outside of the region were relatively accurate for predicting coho salmon rearing distributions, smolt production per km of total rearing habitat, and adult spawner abundance. Based on this, habitat-based models used to help develop escapement goals in other regions may be similarly useful in the Norton Sound region.