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Results for “Growth”

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At least 793 records · Page 44Linked to original sources

USGS1990

Acid precipitation and food quality: Inhibition of growth and survival in black ducks and mallards by dietary aluminum, calcium and phosphorus

In areas impacted by acid precipitation, water chemistry of acidic ponds and streams often changes, resulting in increased mobilization of aluminum and decreased concentration of calcium carbonate. Aluminum binds with phosphorus and inhibits its uptake by organisms. Thus, invertebrate food organisms used by waterfowl may have inadequate Ca and P or elevated Al for normal growth and development. Acid rain and its effects may be one of the factors negatively impacting American black ducks ( Anas rubripes ) in eastern North America. One-day old mallards ( A. platyrhynchos ) and black ducks were placed on one of three Ca:P regimens: low:low (LL), normal:normal (NN), and low:high (LH) with each regimen divided further into three or four Al levels for 10 weeks. Forty-five % of the black ducks died on nine different diets whereas only 28% of the mallards died on three different diets. Mortality was significantly related to diet in both species. Growth rates for body weight, culmens, wings, and tarsi of both species on control diets exceeded those on many treatment diets but the differences were less apparent for mallards than for black ducks. Differences among treatments were due to both Ca:P and A1 levels.

Archives of Environmental Contamination and Toxico↗

USGS1985

Survival, growth, and histopathological effects of paraquat ingestion in nestling American kestrels (Falco sparverius)

The use of paraquat as a herbicide is becoming more extensive with the increasing popularity of no tillage agriculture, increasing the possibility of exposure for wildlife species. American kestrel (Falco sparverius) nestlings were orally dosed daily with 5 ?l/g of distilled water (controls), 10 mg/kg, 25 mg/kg, or 60 mg/kg of paraquat dichloride (1, 1'-dimethyl-4,4'-bipyridinium) in distilled water from day 1 through day 10. Forty-four percent of the nestlings given 60 mg/kg died after 4 days. Significant differences in growth rates occurred between controls and all paraquat-dosed groups. Reduced skeletal growth occurred in the humerus and femur in the 25 mg/kg and 60 mg/kg groups, and in the radius-ulna and tibiotarsus in the 60 mg/kg group. Skeletons were otherwise normal in appearance. Histopathological examination revealed localized focal necrosis in the liver of one nestling in the 60 mg/kg group and tubular cell degeneration and focal tubular dilation in the kidneys of another. The brain and lungs were unremarkable histologically. These findings suggest that altricial nestling kestrels are more sensitive to paraquat exposure than young or adult birds of precocial species.

Archives of Environmental Contamination and Toxico↗

USGS2026

Storage timescales and the crystal growth history recorded in the layered reservoir of the Unit 3 Kulanaokuaiki Tephra Member of the Uēkahuna Ash from Kīlauea volcano

The Kulanaokuaiki Tephra Unit 3 (900 C.E.) was a subplinian basaltic scoria eruption, the largest known to have occurred at Kīlauea’s summit. The initiation mechanism and cause(s) of this highly hazardous eruption remain poorly understood, particularly as this style of activity has not been observed in the modern period. We use olivine diffusion timescales from Fe-Mg and lithium zoning to assess magma storage timescales and evaluate evidence for mixing prior to eruption. Of the 200 crystals assessed, 55% are normally zoned for forsterite and 45% are non-zoned. Zoned crystals (> 1 mm) ( n = 96) have average compositions of Fo 89 cores and Fo 81 rims, while small crystals 0.5–1 mm ( n = 14) have Fo 85 cores and Fo 82 rims. Modeled Fo diffusion timescales range from < 1 to 12.6 years (median of 3.0 years). Lithium maps in 32 of the forsterite-zoned crystals reveal a variety of lithium zoning types, most of which we attribute to crystal growth. Many lithium profiles are coupled to phosphorus within the outer ~ 100 μm of the crystal ( n = 17), reflecting growth processes and precluding their use for diffusion studies. Overall, our Unit 3 olivine dataset displays no evidence of magmatic priming shortly prior to eruption, unlike prior observations for the basaltic subplinian eruption of the Keanakāko‘i Tephra Unit E (1650 C.E.). Thus, explosive eruption magmas may be stored for considerably longer than previously thought, and magmatic priming is not a necessary precursor for Kīlauea’s explosive eruptions. We hypothesize that gas-driven filter pressing from crystallization of microlites and macrocrysts in the reservoir slurry contributed to the explosivity of the Unit 3 eruption.

Hawaii↗

USGS2003

Feedback dynamics of grazing lawns: Coupling vegetation change with animal growth

We studied the effects of grazing by Black Brant (Branta bernicla nigricans) geese (hereafter Brant) on plant community zonation and gosling growth between 1987 and 2000 at a nesting colony in southwestern Alaska. The preferred forage of Brant, Carex subspathacea, is only found as a grazing lawn. An alternate forage species, C. ramenskii, exists primarily as meadow but also forms grazing lawns when heavily grazed. We mowed plots of ungrazed C. ramenskii meadows to create swards that Brant could select and maintain as grazing lawns. Fecal counts were higher on mowed plots than on control plots in the year after plots were mowed. Both nutritional quality and aboveground biomass of C. ramenskii in mowed plots were similar to that of C. subspathacea grazing lawns. The areal extent of grazing lawns depends in part on the population size of Brant. High Brant populations can increase the areal extent of grazing lawns, which favors the growth of goslings. Grazing lawns increased from 3% to 8% of surface area as the areal extent of C. ramenskii meadows declined between 1991 and 1999. Gosling mass was lower early in this time period due to density dependent effects. As the goose population stabilized, and area of grazing lawns increased, gosling mass increased between 1993 and 1999. Because larger goslings have increased survival, higher probability of breeding, and higher fecundity, herbivore-mediated changes in the distribution grazing lawn extent may result in a numerical increase of the population within the next two decades.

Oecologia↗

USGS2025

Growth of a passive lava lake during the 2020–2021 eruption of Kīlauea volcano, Hawaii

We investigate the growth of a passive lava lake in Halemaʻumaʻu crater during the December 2020 to May 2021 eruption of Kīlauea volcano, Hawaii. Fed by vents above their surfaces, the formation of passive lava lakes in topographic lows is an important process in the growth of basaltic volcanoes. We captured visible and thermal images during 17 helicopter overflights and applied structure-from-motion photogrammetry to create digital elevation models and orthomosaics of Halemaʻumaʻu. These data products allowed us to track eruptive activity and processes. The bulk time-averaged discharge rate (TADR) in December 2020 initially exceeded 100 m 3 s –1 but decreased to < 10 m 3 s –1 within seven days. By February 2021, TADR was < 2 m 3 s –1 and continued to decrease until the eruption ended in May 2021. A total volume of 40.6 ± 0.5 × 10 6 m 3 of lava filled Halemaʻumaʻu to a depth of 225 m. As TADR decreased, the lake progressively developed an immobile, solidified crust, beginning with surfaces farthest from the vent. This immobile surface rose endogenously, whereas exogenous surface rise occurred near the vent. Eruptive activity at a vent ended when the level of the lake surface exceeded that of the vent, which we attribute to the effects of lava sitting above the vent on ascending magma. Regular helicopter overflights, combined with field observations and the extensive monitoring network at Kīlauea, generated an unprecedented density of observations that provide insights into the emplacement of passive lava lakes and how these eruptions wane and end.

Hawaii↗

USGS2017

Vertical self-sorting behavior in juvenile Chinook salmon (Oncorhynchus tshawytscha): evidence for family differences and variation in growth and morphology

Life history variation is fundamental to the evolution of Pacific salmon and their persistence under variable conditions. We discovered that Chinook salmon sort themselves into surface- and bottom-oriented groups in tanks within days after exogenous feeding. We hypothesised that this behaviour is correlated with subsequent differences in body morphology and growth (as measured by final length and mass) observed later in life. We found consistent morphological differences between surface and bottom phenotypes. Furthermore, we found that surface and bottom orientation within each group is maintained for at least one year after the phenotypes were separated. These surface and bottom phenotypes are expressed across genetic stocks, brood years, and laboratories and we show that the proportion of surface- and bottom-oriented offspring also differed among families. Importantly, feed delivery location did not affect morphology or growth, and the surface fish were longer than bottom fish at the end of the rearing experiment. The body shape of the former correlates with wild individuals that rear in mainstem habitats and migrate in the fall as subyearlings and the latter resemble those that remain in the upper tributaries and migrate as yearling spring migrants. Our findings suggest that early self-sorting behaviour may have a genetic basis and be correlated with other phenotypic traits that are important indicators for juvenile migration timing.

Environmental Biology of Fishes↗

USGS2016

Estimating the effects of 17α-ethinylestradiol on stochastic population growth rate of fathead minnows: a population synthesis of empirically derived vital rates

Urban freshwater streams in arid climates are wastewater effluent dominated ecosystems particularly impacted by bioactive chemicals including steroid estrogens that disrupt vertebrate reproduction. However, more understanding of the population and ecological consequences of exposure to wastewater effluent is needed. We used empirically derived vital rate estimates from a mesocosm study to develop a stochastic stage-structured population model and evaluated the effect of 17α-ethinylestradiol (EE2), the estrogen in human contraceptive pills, on fathead minnow Pimephales promelas stochastic population growth rate. Tested EE2 concentrations ranged from 3.2 to 10.9 ng L −1 and produced stochastic population growth rates (λ S ) below 1 at the lowest concentration, indicating potential for population decline. Declines in λ S compared to controls were evident in treatments that were lethal to adult males despite statistically insignificant effects on egg production and juvenile recruitment. In fact, results indicated that λ S was most sensitive to the survival of juveniles and female egg production. More broadly, our results document that population model results may differ even when empirically derived estimates of vital rates are similar among experimental treatments, and demonstrate how population models integrate and project the effects of stressors throughout the life cycle. Thus, stochastic population models can more effectively evaluate the ecological consequences of experimentally derived vital rates.

Ecotoxicology↗

USGS2024

Change in growth and prey utilization for a native salmonid following invasion by an omnivorous minnow in an oligotrophic reservoir

Aquatic invasive species can affect food web structure, native fish growth, and production, depending on the traits of the invasive species and the pre-invasion conditions of the ecosystem. Thermal tolerances and behavioral traits can further influence differential exploitation of resources shared between native and invasive species. An unauthorized introduction of redside shiner ( Richardsonius balteatus ) into reservoirs in the Upper Skagit River, Washington, USA caused concern of potential competition, decreased production, and recruitment of rainbow trout ( Oncorhynchus mykiss ). We combined bioenergetics modeling and stable isotope analysis with field data to quantify consumption demand of native and invasive fishes and related consumption to the availability of key zooplankton prey. Per capita consumption on Daphnia by redside shiner was low; however, their high abundance imposed considerable demand on prey resources in Ross Lake. Although monthly consumption demand by the fish community was less than 50% of the monthly production and biomass of Daphnia in Ross Lake, the current Daphnia densities and growth of rainbow trout were considerably lower than before the invasion. These reductions correspond to lower annual consumption of Daphnia . Our study provides insight on mechanisms that influence food web impacts of an invasive omnivore in cold-water reservoirs.

Washington↗

USGS2016

A global review of freshwater crayfish temperature tolerance, preference, and optimal growth

Conservation efforts, environmental planning, and management must account for ongoing ecosystem alteration due to a changing climate, introduced species, and shifting land use. This type of management can be facilitated by an understanding of the thermal ecology of aquatic organisms. However, information on thermal ecology for entire taxonomic groups is rarely compiled or summarized, and reviews of the science can facilitate its advancement. Crayfish are one of the most globally threatened taxa, and ongoing declines and extirpation could have serious consequences on aquatic ecosystem function due to their significant biomass and ecosystem roles. Our goal was to review the literature on thermal ecology for freshwater crayfish worldwide, with emphasis on studies that estimated temperature tolerance, temperature preference, or optimal growth. We also explored relationships between temperature metrics and species distributions. We located 56 studies containing information for at least one of those three metrics, which covered approximately 6 % of extant crayfish species worldwide. Information on one or more metrics existed for all 3 genera of Astacidae, 4 of the 12 genera of Cambaridae, and 3 of the 15 genera of Parastacidae. Investigations employed numerous methodological approaches for estimating these parameters, which restricts comparisons among and within species. The only statistically significant relationship we observed between a temperature metric and species range was a negative linear relationship between absolute latitude and optimal growth temperature. We recommend expansion of studies examining the thermal ecology of freshwater crayfish and identify and discuss methodological approaches that can improve standardization and comparability among studies.

Reviews in Fish Biology and Fisheries↗

USGS2010

Tree growth and mortality during 20 years of managing a Green-Tree Reservoir in Arkansas, USA

Green-Tree Reservoirs (GTR) are bottomland hardwood forests that are flooded during late fall and winter to provide waterfowl habitat. Early reports suggested that increased moisture improved tree growth and mast production; however, recent reports showed reduced vigor and growth. This study examines the effects of 20 years of GTR management practices in the Felsenthal National Wildlife Refuge, Crossett, Arkansas. Tree species composition, size characteristics, and vigor classes were measured in 1990, 1995, 2001, and 2006. The overall annual tree mortality rate was 2.6%, with high elevations at 1.7% and low elevations at 3.1%. Annual mortality rates exceeded 3% for willow oak ( Quercus phellos ) and water hickory ( Carya aquatica ), while rates for Nuttall oak ( Q. texana ), overcup oak ( Q. lyrata ), and sweetgum ( Liquidambar styraciflua .) were lower at 2.8, 2.4, and 1.5%, respectively. Tree health (vigor) has degraded substantially for over 60% of trees initially rated in good or fair condition. Statistical probit models were generated to predict short-term (5 years) and long-term (15 years) vigor degradation. Low numbers of saplings and little advanced regeneration indicated lack of tree replacement, suggesting that inundation strategies of the GTR management may have long-term impacts on forest structure and composition in the southeastern United States.

Arkansas↗

USGS1981

Crystal growth of calcite from calcium bicarbonate solutions at constant P CO 2 and 25°C: a test of a calcite dissolution model

A highly reproducible seeded growth technique was used to study calcite crystallization from calcium bicarbonate solutions at 25°C and fixed carbon dioxide partial pressures between 0.03 and 0.3 atm. The results are not consistent with empirical crystallization models that have successfully described calcite growth at low P CO 2 (< 10 −3 atm). Good agreement was found between observed crystallization rates and those calculated from the calcite dissolution rate law and mechanism proposed by Plummer et al . (1978).

Geochimica et Cosmochimica Acta↗

USGS1995

238U-234U-230Th chronometry of Fe-Mn crusts: Growth processes and recovery of thorium isotopic ratios of seawater

Comparison of ( ( 234 U)excess ( 238 U ) "> 234 U) excess ⁄ ( 238 U) and ( ( 230 Th 232 Th "> 230 Th ⁄ 232 Th ) activity ratios in oceanic Fe-Mn deposits provides a method for assessing the closed-system behaviour of 238 U- 234 U- 230 Th, as well as variations in the initial uranium and thorium isotopic ratios of the precipitated metal oxides. This approach is illustrated using a Fe-Mn crust from Lotab seamount (Marshall Islands, west equatorial Pacific). Here we report uranium and thorium isotopic compositions in five subsamples from the surface of one large 5 cm diameter botryoid of this crust, and from two depth profiles of the outermost rim of the same botryoid. The decrease of ( ( 234 U)excess ( 238 U ) "> 234 U) excess ⁄ ( 238 U) and ( ( 230 Th 232 Th "> 230 Th ⁄ 232 Th ) activity ratio with depth in the two profiles gives mean growth rates, for the last 150 ka, of 7.8 ± 2 mm/Ma and 6.6 ± 1 mm/Ma, respectively. All data points (surface and core samples) but one, define a linear correlation in the Ln ( 230 Th 232 Th − Ln ( 234 U)excess ( 238 U ) "> Ln ( ( 230 Th 232 Th "> 230 Th ⁄ 232 Th ) −Ln[ ( ( 234 U)excess ( 238 U ) "> 234 U) excess ⁄ ( 238 U) ] diagram. This correlation indicates that for all points the U-Th system remained closed after the Fe-Mn layer precipitated, and that the different samples possessed the same initial Uranium and thorium isotope ratios. Furthermore, these results show that the preserved surface of this Fe-Mn crust may not be the present-day growth surface, and that the thorium and uranium isotopic ratios of seawater in west equatorial Pacific have not changed during the past 150 ka. The initial thorium activity ratio is estimated from the correlation obtained between Ln ( 230 Th 232 Th − Ln ( 234 U)excess ( 238 U ) "> Ln ( ( 230 Th 232 Th "> 230 Th ⁄ 232 Th ) −Ln Ln ( 230 Th 232 Th − Ln ( 234 U)excess ( 238 U ) ">[ ( ( 234 U)excess ( 238 U ) "> 234 U) excess ⁄ ( 238 U) ] .

Lotab Seamount, Pacific Ocean↗

USGS1990

Factors controlling late Cenozoic continental margin growth from the Ebro Delta to the western Mediterranean deep sea

The Ebro continental margin sedimentation system originated with a Messinian fluvial system. This system eroded both a major subaerial canyon cutting the margin southeastward from the present Ebro Delta and an axial valley that drained northeastward down Valencia Trough. Post-Messinian submergence of this topography and the Pliocene regime of high sea levels resulted in a marine hemipelagic drape over the margin. Late Pliocene to Pleistocene glacial climatic cycles, drainagebasin deforestation, and sea-level lowstands combined to increase sediment supply, cause the margin to prograde, and create a regime of lowstand sediment-gravity flows in the deeper margin. The depositional patterns of regressive, transgressive and highstand sea-level regimes suggest that location of the sediment source near the present Ebro Delta throughout the late Cenozoic, southward current advection of sediment, and greater subsidence in the southern margin combined to cause generally asymmetric progradation of the margin to the southeast. Thicker, less stable deposits filling the Messinian subaerial canyon underwent multiple retrograde failures, eroded wide gullied canyons and formed unchanneled base-of-slope sediment aprons in the central margin area; other margin areas to the north and south developed a series of channel-levee complexes. On the basin floor, the formation of Valencia Valley over the Messinian subaerial valley and earlier faults led to draining of about 20% of the Ebro Pleistocene sediment from channel-levee complexes through the valley to prograde Valencia Fan as much as 500 km northeast of the margin. Thus, the Ebro margin has two growth directions, mainly southeastward during higher sea levels, and eastward to northeastward during lower sea levels. The northeastward draining of turbidity currents has produced unusually thin and widely dispersed turbidite systems compared to those on ponded basin floors. During the past few centuries, man's impact has exceeded natural controls on Ebro margin growth. Deforestation of the drainage basin more than doubled the normal Holocene sediment supply, and construction of dams then reduced the supply by 95%. This reduction of the past 50 years has caused erosion of the delta and contamination of bottom sediment because normal Holocene sediment discharge is not available to prograde the delta or help dilute pollutants.

Marine Geology↗

USGS1992

Geochronology and subsurface stratigraphy of Pukapuka and Rakahanga atolls, Cook Islands: Late Quaternary reef growth and sea level history

Eustatic sea-level cycles superposed on thermal subsidence of an atoll produce layers of high sea-level reefs separated by erosional unconformities. Coral samples from these reefs from cores drilled to 50 m beneath the lagoons of Pukapuka and Rakahanga atolls, northern Cook Islands give electron spin resonance (ESR) and U-series ages ranging from the Holocene to 600,000 yr B.P. Subgroups of these ages and the stratigraphic position of their bounding unconformities define at least 5 periods of reef growth and high sea-level (0–9000 yr B.P., 125,000–180,000 yr B.P., 180,000–230,000 yr B.P., 300,000–460,000 yr B.P., 460,000–650,000 yr B.P.). Only two ages fall within error of the last interglacial high sea-level stand (∼125,000–135,000 yr B.P.). This paucity of ages may result from extensive erosion of the last intergracial reef. In addition, post-depositional isotope exchange may have altered the time ages of three coral samples to apparent ages that fall within glacial stage 6. For the record to be preserved, vertical accretion during rising sea-level must compensate for surface lowering from erosion during sea-level lowstands and subsidence of the atoll; erosion rates (6–63 cm/1000 yr) can therefore be calculated from reef accretion rates (100–400 cm/1000 yr), subsidence rates (2–6 cm/1000 yr), and the duration of island submergence (8–15% of the last 600,000 yr). The stratigraphy of coral ages indicates island subsidence rates of 4.5 ± 2.8 cm/1000 yr for both islands. A model of reef growth and erosion based on the stratigraphy of the Cook Islands atolls suggests average subsidence and erosion rates of between 3–6 and 15–20 cm/1000 yr, respectively.

Palaeogeography, Palaeoclimatology, Palaeoecology↗

USGS1988

Growth, carcass composition, and taste of rainbow trout of different strains fed diets containing primarily plant or animal protein

Ten rainbow trout ( Salmo gairdneri ) strains were evaluated during early growth from 30 g to 250 g on two diets — one based on plant protein (soybean and cottonseed meal) and the other on animal protein (fish meal). Diets were formulated to be nutritionally isocaloric and isonitrogenous. Fish were fed identical starter diets until they weighed 30 g. Significant differences in growth rate were found attributable to fish strain. Differences associated with diet were nonsignificant. Percent dress-out data based on eviscerated weight, deboned weight, and fillet weight also showed significant differences in yield attributable to fish strain, but not to diet. Carcass composition varied among strains, but none of the differences could be attributed to diet. Organoleptic tests showed no differences in flesh acceptability associated with either fish strain or diet, and all trout tested were equally acceptable to human taste panels.

Aquaculture↗

USGS1995

Circulating growth hormone, cortisol and thyroxine levels after 24 h seawater challenge of yearling coho salmon at different developmental stages

The response of the endocrine system to short-term exposure to sea water (SW) was examined before, during and after the parr-smolt transformation of coho salmon. Five transfers of yearling coho salmon ( Oncorhynchus kisutch ) from fresh water (FW) to FW, or from FW to SW for 24 h were carried out between March and September. Condition factor declined significantly in late April, and gill Na + , K + -ATPase activity was elevated between late March and early June. Increases in plasma osmolality after transfer to SW were high in early March, low from late March — early June and slightly higher in September. In fish transferred from FW to FW, plasma levels of thyroxine (T 4 ) were elevated in late March-late April, and plasma levels of cortisol were high in late March-early June; both hormones declined to early March levels thereafter. Growth hormone (GH) levels increased in late March and remained elevated for the duration of the study. A significant linear correlation existed between plasma cortisol and growth hormone levels in FW to FW transferred fish. After SW transfer, T 4 levels were significantly lower than values in FW controls in early March and were significantly higher than FW control levels in early June and early September. Cortisol levels increased significantly after each transfer except in late April. However, compared with the early March and early September transfers, the magnitude of the elevation was reduced in late March. GH levels were significantly elevated above FW control levels after seawater transfer in late April only, despite a trend for mean GH levels to be higher after transfer in June and September. Thus, minimal increases in cortisol, and increases in GH occur after SW transfer of functional (optimally hypo-osmoregulating) smolts.

Aquaculture↗

USGS2022

Complex life-cycles in trophically transmitted helminths: Do the benefits of increased growth and transmission outweigh generalism and complexity costs?

Why do so many parasitic worms have complex life-cycles? A complex life-cycle has at least two hypothesized costs: (i) worms with longer life-cycles, i.e. more successive hosts, must be generalists at the species level, which might reduce lifetime survival or growth, and (ii) each required host transition adds to the risk that a worm will fail to complete its life-cycle. Comparing hundreds of trophically transmitted acanthocephalan , cestode , and nematode species with different life-cycles suggests these costs are weaker than expected. Helminths with longer cycles exhibit higher species-level generalism without impaired lifetime growth. Further, risk in complex life-cycles is mitigated by increasing establishment rates in each successive host. Two benefits of longer cycles are transmission and production. Longer cycles normally include smaller (and thus more abundant) first hosts that are likely to consume parasite propagules, as well as bigger (and longer-lived) definitive hosts, in which adult worms grow to larger and presumably more fecund reproductive sizes. Additional factors, like host immunity or dispersal, may also play a role, but are harder to address. Given the ubiquity of complex life-cycles, the benefits of incorporating or retaining hosts in a cycle must often exceed the costs.

Current Research in Parasitology & Vector-borne Di↗

USGS2024

An integrated analysis for estimation of survival, growth, and movement of unmarked juvenile anadromous fish

Managers invest substantial resources to promote recovery of declining anadromous fish stocks. Recovery strategies are manifold and often include management actions intended to stimulate somatic growth, increase in-river survival, and motivate juvenile outmigration during favorable environmental conditions. Evaluating the efficacy of these management actions is difficult, however, because monitoring data that explicitly track individuals from egg deposition to juvenile outmigration are typically lacking. We developed an integrated population model that links two different and often collected types of anadromous fish monitoring data: spawning ground surveys and rotary screw trap juvenile catch data. The integrated model accounts for incomplete detection and uses the two sources of data to estimate juvenile demographic parameters in a multistate framework. We evaluated the model's performance using simulated data under a range of conditions typically encountered in similar surveys. Simulation results indicated that the model estimated juvenile survival, growth, and movement with no-to-minimal bias (i.e., ≥ 50 % of simulations ± 0–0.05). As an example case study, we fit the model to empirical fall-run Chinook Salmon ( Oncorhynchus tshawytscha ) monitoring data collected in California's Central Valley, U.S.A. In doing so, we evaluated the influence of environmental conditions (e.g., discharge, water temperature) and habitat availability on juvenile demographic rates. We demonstrated that through our integrated approach we could estimate state transition probabilities that are typically inestimable for naturally produced, unmarked juvenile fish when using traditional statistical approaches to analyze these types of monitoring data. Furthermore, the structure of our model can serve as a useful foundation for decision-support models within adaptive management programs by directly linking management actions, decision-support-model predictions, and monitoring.

California↗