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At least 1,801 records · Page 100Linked to original sources
USGS2005

Invaders eating invaders: Exploitation of novel alien prey by the alien shimofuri goby in the San Francisco Estuary, California

The shimofuri goby (Tridentiger bifasciatus), which is native to Asian estuaries, was recently introduced to the San Francisco Estuary, California, USA. We conducted gut content analyses to examine the goby's feeding ecology in this highly invaded estuary. Shimofuri gobies were generalist predators on benthic invertebrates, consuming seasonally abundant prey, especially amphipods (Corophium spp.). In addition, shimofuri goby utilized two novel prey items not exploited by other resident fishes - hydroids (Cordylophora caspia) and barnacle (Balanus improvisus) cirri, both of which are alien. The shimofuri goby's feeding ecology appears well-suited to the fluctuating environment of the San Francisco Estuary and may partially explain observed increases in shimofuri goby abundance compared with declines in populations of some native species. ?? Springer 2005.

Biological Invasions↗
USGS2014

Tidal and seasonal effects on survival rates of the endangered California clapper rail: Does invasive Spartina facilitate greater survival in a dynamic environment?

Invasive species frequently degrade habitats, disturb ecosystem processes, and can increase the likelihood of extinction of imperiled populations. However, novel or enhanced functions provided by invading species may reduce the impact of processes that limit populations. It is important to recognize how invasive species benefit endangered species to determine overall effects on sensitive ecosystems. For example, since the 1990s, hybrid Spartina ( Spartina foliosa × alterniflora ) has expanded throughout South San Francisco Bay, USA, supplanting native vegetation and invading mudflats. The endangered California clapper rail ( Rallus longirostris obsoletus ) uses the tall, dense hybrid Spartina for cover and nesting, but the effects of hybrid Spartina on clapper rail survival was unknown. We estimated survival rates of 108 radio-marked California clapper rails in South San Francisco Bay from January 2007 to March 2010, a period of extensive hybrid Spartina eradication, with Kaplan–Meier product limit estimators. Clapper rail survival patterns were consistent with hybrid Spartina providing increased refuge cover from predators during tidal extremes which flood native vegetation, particularly during the winter when the vegetation senesces. Model averaged annual survival rates within hybrid Spartina dominated marshes before eradication (Ŝ = 0.466) were greater than the same marshes posttreatment (Ŝ = 0.275) and a marsh dominated by native vegetation (Ŝ = 0.272). However, models with and without marsh treatment as explanatory factor for survival rates had nearly equivalent support in the observed data, lending ambiguity as to whether hybrid Spartina facilitated greater survival rates than native marshland. Conservation actions to aid in recovery of this endangered species should recognize the importance of available of high tide refugia, particularly in light of invasive species eradication programs and projections of future sea-level rise.

California↗
USGS2022

Establishment of invasive Black Carp (Mylopharyngodon piceus) in the Mississippi River basin: Identifying sources and year classes contributing to recruitment

Black Carp ( Mylopharyngodon piceus ) was imported to the USA to control aquaculture pond snails. This species has escaped captivity and occurs in parts of the Mississippi River, several tributaries, and floodplain lakes, which is concerning due to potential competition with native fishes and predation on native mussels, many of which are imperiled. However, Black Carp captures have primarily been incidental by commercial fishers, and evidence of reproduction in the wild is limited. The objectives of this study were to assess relative abundance of aquaculture-origin and wild Black Carp using ploidy and otolith stable isotope analysis, identify spatial extent of natural reproduction using otolith microchemistry, assess age distributions of wild and aquaculture-source Black Carp to infer years in which natural reproduction occurred and timing of aquaculture escapement or introductions, and estimate size and age at maturation to assess whether recruitment to adulthood has occurred. Results revealed that Black Carp are established in parts of the Mississippi River basin based on findings that: (1) non-captive Black Carp primarily consist of fertile, naturally-reproduced fish, (2) reproduction has occurred in several rivers, (3) multiple year classes of wild fish are present, and (4) wild fish have recruited to adulthood. Multiple introductions or escapements of aquaculture-source fish into the wild, including both fertile and functionally sterile individuals, were also inferred. Individual growth appears to be rapid, although considerable variation was observed among fish. Additional study is suggested to refine understanding of where and when Black Carp reproduction is occurring in the Mississippi River basin.

Arkansas, Illinois, Kentucky, Louisiana, Missouri,↗
USGS2023

Elodea mediates juvenile salmon growth by altering physical structure in freshwater habitats

Invasive species introductions in high latitudes are accelerating and elevating the need to address questions of their effects on Subarctic and Arctic ecosystems. As a driver of ecosystem function, submerged aquatic vegetation is one of the most deleterious biological invasions to aquatic food webs. The aquatic plant Elodea spp. has potential to be a widespread invader to Arctic and Subarctic ecosystems and is already established in 19 waterbodies in Alaska, USA. Elodea spp. has been found to alter ecosystem processes through multiple pathways; yet little is known about the impact of Elodea spp. on fish life history. A primary concern is the effect of Elodea spp. on juvenile Pacific salmon ( Oncorhynchus spp.), because this invading plant can form dense stands in littoral zones, potentially impacting important freshwater rearing habitats used by juvenile fish for foraging and refuge from predators. We used a field experiment to test the effect of Elodea spp. on juvenile coho salmon ( O. kisutch ) growth in an infested lake near Cordova, Alaska, USA. We found that Elodea spp. stands result in reduced growth and a lower trophic position for juvenile coho salmon over the summer compared to habitats dominated by a native assemblage of aquatic plants. While infested sites were not associated with significant changes in water condition or primary productivity compared to sites dominated by native vegetation, zooplankton densities were reduced, and Elodea spp. height and vegetation richness increased macroinvertebrate densities. Combined, these results indicate that Elodea spp. may alter the flow of energy to juvenile salmon by restructuring space and affecting prey resources for rearing fish. Furthermore, these results suggest that widespread establishment of Elodea spp. may alter the quality of habitat for juvenile salmon and, by affecting juvenile fish growth, could lead to population-level impacts on salmon returns.

Biological Invasions↗
USGS2020

A century of pollen foraging by the endangered rusty patched bumble bee (Bombus affinis): Inferences from molecular sequencing of museum specimens

In 2017 the rusty patched bumble bee ( Bombus affinis ) became the first bee listed under the Endangered Species Act in the continental United States due to population declines and an 87% reduction in the species’ distribution. Bombus affinis decline began in the 1990s, predating modern bee surveying initiatives, and obfuscating drivers of decline. While understood to be a highly generalist forager, little is known about the role that resource limitation or shifting floral community composition could have played in B. affinis decline. Determining which floral species support B. affinis could assist conservation efforts where B. affinis persists and identify floral species for restoration efforts. We constructed a historical foraging profile of B. affinis via DNA sequencing of pollen from museum specimens spanning seven states collected from 1913 to 2013. Molecular analysis revealed no temporal changes in the floral richness or composition of B. affinis pollen samples across our sampling period. Likewise, we found no temporal changes in the presence or proportion of native vs. introduced species in pollen samples, though we observed much greater use of introduced floral species than previously determined for B. affinis . Floral community composition was regionally dissimilar, inconsistent with patterns of B. affinis decline by state. Our results suggest B. affinis decline was unlikely to have been driven by spatial or temporal limitations of specific floral species. This work greatly expands the known forage of B. affinis and will provide managers with insight to aid the conservation of B. affinis .

Biodiversity and Conservation↗
USGS2022

Cryptic extinction risk in a western Pacific lizard radiation

Cryptic ecologies, the Wallacean Shortfall of undocumented species’ geographical ranges and the Linnaean Shortfall of undescribed diversity, are all major barriers to conservation assessment. When these factors overlap with drivers of extinction risk, such as insular distributions, the number of threatened species in a region or clade may be underestimated, a situation we term ‘cryptic extinction risk’. The genus Lepidodactylus is a diverse radiation of insular and arboreal geckos that occurs across the western Pacific. Previous work on Lepidodactylus showed evidence of evolutionary displacement around continental fringes, suggesting an inherent vulnerability to extinction from factors such as competition and predation. We sought to (1) comprehensively review status and threats, (2) estimate the number of undescribed species, and (3) estimate extinction risk in data deficient and candidate species, in Lepidodactylus . From our updated IUCN Red List assessment, 60% of the 58 recognized species are threatened (n = 15) or Data Deficient (n = 21), which is higher than reported for most other lizard groups. Species from the smaller and isolated Pacific islands are of greatest conservation concern, with most either threatened or Data Deficient, and all particularly vulnerable to invasive species. We estimated 32 undescribed candidate species and linear modelling predicted that an additional 18 species, among these and the data deficient species, are threatened with extinction. Focusing efforts to resolve the taxonomy and conservation status of key taxa, especially on small islands in the Pacific, is a high priority for conserving this remarkably diverse, yet poorly understood, lizard fauna. Our data highlight how cryptic ecologies and cryptic diversity combine and lead to significant underestimation of extinction risk.

Biodiversity and Conservation↗
USGS2014

Spatial genetic structure of bristle-thighed curlews (Numenius tahitiensis): Breeding area differentiation not reflected on the non-breeding grounds

Migratory birds occupy geographically and ecologically disparate areas during their annual cycle with conditions on breeding and non-breeding grounds playing separate and important roles in population dynamics. We used data from nuclear microsatellite and mitochondrial DNA control region loci to assess the breeding and non-breeding spatial genetic structure of a transoceanic migrant shorebird, the bristle-thighed curlew. We found spatial variance in the distribution of allelic and haplotypic frequencies between the curlew's two breeding areas in Alaska but did not observe this spatial structure throughout its non-breeding range on low-lying tropical and subtropical islands in the Central Pacific (Oceania). This suggests that the two breeding populations do not spatially segregate during the non-breeding season. Lack of migratory connectivity is likely attributable to the species' behavior, as bristle-thighed curlews exhibit differential timing of migration and some individuals move among islands during non-breeding months. Given the detrimental impact of many past and current human activities on island ecosystems, admixture of breeding populations in Oceania may render the bristle-thighed curlew less vulnerable to perturbations there, as neither breeding population will be disproportionally affected by local habitat losses or by stochastic events. Furthermore, lack of migratory connectivity may enable bristle-thighed curlews to respond to changing island ecosystems by altering their non-breeding distribution. However, availability of suitable non-breeding habitat for curlews in Oceania is increasingly limited on both low-lying and high islands by habitat loss, sea level rise, and invasive mammalian predators that pose a threat to flightless and flight-compromised curlews during the molting period.

Conservation Genetics↗
USGS2021

Genome-wide SNP analysis of three moose subspecies at the southern range limit in the contiguous United States

Genome-wide evaluations of genetic diversity and population structure are important for informing management and conservation of trailing-edge populations. North American moose ( Alces alces ) are declining along portions of the southern edge of their range due to disease, species interactions, and marginal habitat, all of which may be exacerbated by climate change. We employed a genotyping by sequencing (GBS) approach in an effort to collect baseline information on the genetic variation of moose inhabiting the species’ southern range periphery in the contiguous United States. We identified 1920 single nucleotide polymorphisms (SNPs) from 155 moose representing three subspecies from five states: A. a. americana (New Hampshire), A. a. andersoni (Minnesota), and A. a. shirasi (Idaho, Montana, and Wyoming). Molecular analyses supported three geographically isolated clusters, congruent with currently recognized subspecies. Additionally, while moderately low genetic diversity was observed, there was little evidence of inbreeding. Results also indicated > 20% shared ancestry proportions between A. a. shirasi samples from northern Montana and A. a. andersoni samples from Minnesota, indicating a putative hybrid zone warranting further investigation. GBS has proven to be a simple and effective method for genome-wide SNP discovery in moose and provides robust data for informing herd management and conservation priorities. With increasing disease, predation, and climate related pressure on range edge moose populations in the United States, the use of SNP data to identify gene flow between subspecies may prove a powerful tool for moose management and recovery, particularly if hybrid moose are more able to adapt.

Conservation Genetics↗
USGS2023

A 37 K SNP array for the management and conservation of Golden Eagles (Aquila chrysaetos)

We describe the development of a custom 37 K Affymetrix Axiom myDesign single nucleotide polymorphism (SNP) array for a culturally and ecologically important apex predator, the golden eagle ( Aquila chrysaetos ). Using this SNP array, we performed population genomic analysis on 154 individuals of known natal localities and detected three genetic clusters that we designated as Taiga/High Arctic, Great Basin, and Rocky Mountains/Great Plains. Each of these clusters appears to display clinal variation within these geographic regions. After determining genetic structure, we performed an assignment test of 32 individuals, five of which were siblings of individuals used in the assessment of genetic structure, three had associated telemetry data, and the remaining individuals were of unknown natal locations. Using this array, four siblings were correctly assigned to the same geographic region as their sibling and the genetic assignment of the radio telemetered birds agreed with the expected movement patterns displayed by these individuals. For the remaining individuals, we were able to assign all but five individuals to one of the three genetic clusters. Our genetic assignments illustrates the utility of this SNP array to accurately assign most individuals to predesignated geographical regions. While further compiling genetic and other data types, we can increase the power of this tool for identifying those breeding populations that may need assistance due to anthropogenic stressors that negatively impact their population viability. The use of this genetic resource will help substantiate decisions by multiple conservation groups that seek to preserve the natural population structure of the golden eagle.

Conservation Genetics↗
USGS2004

The habitats exploited and the species trapped in a Caribbean island trap fishery

We visually observed fish traps in situ to identify the habitats exploited by the U.S. Virgin Islands fishery and to document species composition and abundance in traps by habitat. Fishers set more traps in algal plains than in any other habitat around St. John. Coral reefs, traditionally targeted by fishers, accounted for only 16% of traps. Traps in algal plain contained the highest number of fishes per trap and the greatest numbers of preferred food species. Traps on coral reefs contained the most species, 41 of the 59 taxa observed in the study. Acanthurus coeruleus was the most abundant species and Acanthuridae the most abundant family observed in traps. Piscivore numbers were low and few serranids were observed. Traps in algal plain contained the most fishes as a result of: ecological changes such as shifts in habitat use, mobility of species and degradation of nearshore habitat (fishery independent); and, catchability of fishes and long-term heavy fishing pressure (fishery dependent). The low number of serranids per trap, dominance of the piscivore guild by a small benthic predator, Epinephelus guttatus, and dominance of trap contents overall by a small, fast-growing species of a lower trophic guild, Acanthurus coeruleus, all point to years of intense fishing pressure.

Environmental Biology of Fishes↗
USGS2005

Relation of desert pupfish abundance to selected environmental variables in natural and manmade habitats in the Salton Sea basin

We assessed the relation between abundance of desert pupfish, Cyprinodon macularius, and selected biological and physicochemical variables in natural and manmade habitats within the Salton Sea Basin. Field sampling in a natural tributary, Salt Creek, and three agricultural drains captured eight species including pupfish (1.1% of the total catch), the only native species encountered. According to Bray-Curtis resemblance functions, fish species assemblages differed mostly between Salt Creek and the drains (i.e., the three drains had relatively similar species assemblages). Pupfish numbers and environmental variables varied among sites and sample periods. Canonical correlation showed that pupfish abundance was positively correlated with abundance of western mosquitofish, Gambusia affinis, and negatively correlated with abundance of porthole livebearers, Poeciliopsis gracilis, tilapias (Sarotherodon mossambica and Tilapia zillii), longjaw mudsuckers, Gillichthys mirabilis, and mollies (Poecilia latipinnaandPoecilia mexicana). In addition, pupfish abundance was positively correlated with cover, pH, and salinity, and negatively correlated with sediment factor (a measure of sediment grain size) and dissolved oxygen. Pupfish abundance was generally highest in habitats where water quality extremes (especially high pH and salinity, and low dissolved oxygen) seemingly limited the occurrence of nonnative fishes. This study also documented evidence of predation by mudsuckers on pupfish. These findings support the contention of many resource managers that pupfish populations are adversely influenced by ecological interactions with nonnative fishes. ?? Springer 2005.

California↗
USGS2006

Lake whitefish and lake herring population structure and niche in ten south-central Ontario lakes

This study compares simple fish communities of ten oligotrophic lakes in south-central Ontario. Species densities and population size structure vary significantly among these lake communities depending on fish species present beyond the littoral zone. Lake whitefish are fewer and larger in the presence of lake herring than in their absence. Diet analysis indicates that lake whitefish shift from feeding on both plankton and benthic prey when lake herring are absent to a primarily benthic feeding niche in the presence of lake herring. When benthic round whitefish are present, lake whitefish size and density decline and they move lower in the lake compared to round whitefish. Burbot are also fewer and larger in lakes with lake herring than in lakes without herring. Burbot, in turn, appear to influence the population structure of benthic coregonine species. Lower densities of benthic lake whitefish and round whitefish are found in lakes containing large benthic burbot than in lakes with either small burbot or where burbot are absent. Predation on the pelagic larvae of burbot and lake whitefish by planktivorous lake herring alters the size and age structure of these populations. As life history theory predicts, those species with poor larval survival appear to adopt a bet-hedging life history strategy of long-lived individuals as a reproductive reserve.

Environmental Biology of Fishes↗
USGS2009

Influences of wind-wave exposure on the distribution and density of recruit reef fishes at Kure and Pearl and Hermes Atolls, Northwestern Hawaiian Islands

This paper describes the results of a field survey designed to test the prediction that the density of benthic juveniles of shallow-reef fishes is greater on wind-wave "exposed" sectors of a pair of isolated oceanic atolls (Kure, Pearl and Hermes) at the far northwestern end of the Hawaiian Islands, an archipelago in which east-northeasterly trade winds dominate onshore water flow and transport by surface currents. The densities of recruits (juveniles ???5 cm total length) were higher overall on windward versus leeward sectors of carbonate rock-rubble back reefs at both atolls, and the pattern was stronger for smaller (likely younger, more recently settled) recruits of four of the five most abundant species and the remainder pooled as an "Other" taxon. The windward-leeward disparity was four-fold greater at Pearl Hermes (the atoll with a three-fold longer perimeter) than at Kure. Resident predator biomass also was correlated with recruit densities, but habitat (benthic substratum) effects were generally weak. The distribution and abundance of recruits and juveniles of the primarily endemic reef fishes on shallow back reefs at these atolls appear partly influenced by relative rates of water flow over windward vs. leeward sectors of barrier reef and by the size, shape, and orientation of habitat parcels that filter out postlarval fishes with relatively weak swimming capabilities like labroids. Whole-reef geomorphology as well as fine-scale habitat heterogeneity and rugosity should be considered among the suite of many factors used to interpret observed spatial patterns of post-settlement juvenile fish distribution at atolls and perhaps some other tropical reefs. ?? The Author(s) 2009.

Environmental Biology of Fishes↗
USGS2010

Utility of mesohabitat features for determining habitat associations of subadult sharks in Georgia’s estuaries

We examined the affects of selected water quality variables on the presence of subadult sharks in six of nine Georgia estuaries. During 231 longline sets, we captured 415 individuals representing nine species. Atlantic sharpnose shark ( Rhizoprionodon terranovae ), bonnethead ( Sphyrna tiburo ), blacktip shark ( Carcharhinus limbatus ) and sandbar shark ( C. plumbeus ) comprised 96.1% of the catch. Canonical correlation analysis (CCA) was used to assess environmental influences on the assemblage of the four common species. Results of the CCA indicated Bonnethead Shark and Sandbar Shark were correlated with each other and with a subset of environmental variables. When the species occurred singly, depth was the defining environmental variable; whereas, when the two co-occurred, dissolved oxygen and salinity were the defining variables. Discriminant analyses (DA) were used to assess environmental influences on individual species. Results of the discriminant analyses supported the general CCA findings that the presence of bonnethead and sandbar shark were the only two species that correlated with environmental variables. In addition to depth and dissolved oxygen, turbidity influenced the presence of sandbar shark. The presence of bonnethead shark was influenced primarily by salinity and turbidity. Significant relationships existed for both the CCA and DA analyses; however, environmental variables accounted for <16% of the total variation in each. Compared to the environmental variables we measured, macrohabitat features (e.g., substrate type), prey availability, and susceptibility to predation may have stronger influences on the presence and distribution of subadult shark species among sites.

Georgia↗
USGS2010

Use of cover habitat by bull trout, Salvelinus confluentus, and lake trout, Salvelinus namaycush, in a laboratory environment

Lacustrine-adfluvial bull trout, Salvelinus confluentus , migrate from spawning and rearing streams to lacustrine environments as early as age 0. Within lacustrine environments, cover habitat provides refuge from potential predators and is a resource that is competed for if limiting. Competitive interactions between bull trout and other species could result in bull trout being displaced from cover habitat, and bull trout may lack evolutionary adaptations to compete with introduced species, such as lake trout, Salvelinus namaycush . A laboratory experiment was performed to examine habitat use and interactions for cover by juvenile (i.e., <80 mm total length) bull trout and lake trout. Differences were observed between bull trout and lake trout in the proportion of time using cover ( F 1,22.6 = 20.08, P < 0.001) and bottom ( F 1,23.7 = 37.01, P < 0.001) habitat, with bull trout using cover and bottom habitats more than lake trout. Habitat selection ratios indicated that bull trout avoided water column habitat in the presence of lake trout and that lake trout avoided bottom habitat. Intraspecific and interspecific agonistic interactions were infrequent, but approximately 10 times greater for intraspecific interactions between lake trout. Results from this study provide little evidence that juvenile bull trout and lake trout compete for cover, and that species-specific differences in habitat use and selection likely result in habitat partitioning between these species.

Environmental Biology of Fishes↗
USGS2014

The role of depth in regulating water quality and fish assemblages in oxbow lakes

We evaluated water quality and fish assemblages in deep (> 3.0 m; N = 7) and shallow (< 1.5 m; N = 6) floodplain lakes in the intensively cultivated Yazoo River Basin (Mississippi, USA) using indirect gradient multivariate procedures. Shallow lakes displayed wide diel oxygen fluctuations, some reaching hypoxic/anoxic conditions for extended periods of time, high suspended solids, and extreme water temperatures. Conversely, deeper lakes were represented by higher visibility, stable oxygen levels, and cooler water temperatures. Fish assemblages in shallow lakes were dominated by tolerant, small-bodied fishes and those able to breathe atmospheric oxygen. Deeper lakes had a greater representation of predators and other large-bodied fishes. Our evaluation suggests fish assemblages are reflective of oxbow lakes water quality, which is shaped by depth. Understanding the interactions between depth, water quality, and fish assemblages may facilitate development of effective management plans for improving conditions necessary to sustain diverse fish assemblages in agriculturally dominated basins.

Environmental Biology of Fishes↗
USGS2017

Piscivore diet response to a collapse in pelagic prey populations

Pelagic fish populations in the upper San Francisco Estuary have experienced significant declines since the turn of the century; a pattern known as the pelagic organism decline (POD). This study investigated food habits of piscivorous fishes over two consecutive fall seasons following the decline of pelagic fish prey. Specifically, this study addressed the contribution of pelagic versus benthic prey to piscivorous fish diets, including the frequency of predation on special-status pelagic species, and the spatial variability in prey consumption. The piscivore community was dominated by Striped Bass and also included small numbers of Sacramento Pikeminnow and Largemouth Bass. Overall, pelagic prey items contributed less than 10% of the diet by weight in both years, whereas pre-POD studies gleaned from the literature found contributions of 39–100%, suggesting a major switch from pelagic to benthic prey resources. Between-year variation in piscivore diets reflected differences in environmental conditions associated with variation in freshwater outflow. No special status fish species were detected in any of the piscivore stomachs examined. The consequences of this pelagic to benthic diet shift warrants further investigation to understand its ecological relevance.

California↗
USGS2017

Energetic requirements of green sturgeon (Acipenser medirostris) feeding on burrowing shrimp (Neotrypaea californiensis) in estuaries: importance of temperature, reproductive investment, and residence time

Habitat use can be complex, as tradeoffs among physiology, resource abundance, and predator avoidance affect the suitability of different environments for different species. Green sturgeon ( Acipenser medirostris ), an imperiled species along the west coast of North America, undertake extensive coastal migrations and occupy estuaries during the summer and early fall. Warm water and abundant prey in estuaries may afford a growth opportunity. We applied a bioenergetics model to investigate how variation in estuarine temperature, spawning frequency, and duration of estuarine residence affect consumption and growth potential for individual green sturgeon. We assumed that green sturgeon achieve observed annual growth by feeding solely in conditions represented by Willapa Bay, Washington, an estuary annually frequented by green sturgeon and containing extensive tidal flats that harbor a major prey source (burrowing shrimp, Neotrypaea californiensis ). Modeled consumption rates increased little with reproductive investment (<0.4%), but responded strongly (10–50%) to water temperature and duration of residence, as higher temperatures and longer residence required greater consumption to achieve equivalent growth. Accordingly, although green sturgeon occupy Willapa Bay from May through September, acoustically-tagged individuals are observed over much shorter durations (34 d + 41 d SD, N = 89). Simulations of <34 d estuarine residence required unrealistically high consumption rates to achieve observed growth, whereas longer durations required sustained feeding, and therefore higher total intake, to compensate for prolonged exposure to warm temperatures. Model results provide a range of per capita consumption rates by green sturgeon feeding in estuaries to inform management decisions regarding resource and habitat protection for this protected species.

Environmental Biology of Fishes↗

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