Adult Migration Research Articles

Migration Distance and Body Condition Influence Shorebird Migration Strategies and Stopover Decisions During Southbound Migration

Technological constraints have limited our ability to compare and determine the proximate and ultimate drivers of migratory behaviour in small-bodied birds. Small VHF transmitters ( 9,000 km; pectoral sandpiper, Calidris melanotos, and white-rumped sandpiper, Calidris fuscicollis) would be more likely to migrate with characteristics of a time-minimizing migration strategy compared to species migrating intermediate distances (5,000-7,500 km; semipalmated sandpiper, Calidris pusilla; and lesser yellowlegs, Tringa flavipes) or shorter distances (~5,000 km; least sandpiper, Calidris minutilla; semipalmated plover, Charadrius semipalmatus), which would migrate with more characteristics of an energy-minimizing strategy. Our results indicate that migration and stopover behaviours for adults matched this prediction; longer distance migrants had longer stopover lengths, departed with higher relative fuel loads, flew with faster ground and airspeeds, and had a lower probability of stopover in North America after departing the subarctic. The predicted relationship between migration distance and migratory strategy was not as clear for juveniles. Despite our prediction that longer distance migrants would be less wind selective at departure and fly into headwinds en route, all species and age classes departed and migrated with supportive winds. Birds with higher estimated fuel loads at departure were less likely to stop in North America after departing the subarctic, indicating that some birds attempted non-stop flights from the subarctic to the Caribbean or South America. Additionally, within species, adults with higher relative fuel loads at departure had a higher detection probability after departing the subarctic, which we interpret as evidence of higher survival compared to juveniles. This study shows that migratory behaviour of shorebirds has predictable patterns based on migration distance that are moderated by body condition of individuals, with potential implications for fitness.

Urban revival by Millennials? Intraurban net migration patterns of young adults, 1980–2010

AbstractThis study investigates neighborhood scale net migration of young adults in the top 20 urbanized areas (UAs) in the United States between 1980 and 2010. Both descriptive and regression analyses show that Generation Xers and Millennials were more likely to net migrate into central locations and less aversive to high density at their young ages than late boomers were in the 1980s. Consumption amenities are a critical factor that distinguishes the net migration patterns between young and old adult groups and became a more important location factor for young adults in the 2000s (late Gen Xers and older Millennials) than in the 1990s (early Gen Xers). There exists a considerable degree of heterogeneity across UAs and neighborhoods even within the same UAs.

Quantifying habitat selection and variability in habitat suitability for juvenile white sharks.

While adult white sharks (Carcharodon carcharias) are apex predators with a circumglobal distribution, juvenile white sharks (JWS) feed primarily on bottom dwelling fishes and tend to be coastally associated. Despite the assumedly easier access to juveniles compared to large, migratory adults, limited information is available on the movements, environments, and distributions of individuals during this life stage. To quantify movement and understand their distribution in the southern California Bight, JWS were captured and fitted with dorsal fin-mounted satellite transmitters (SPOT tags; n = 18). Nine individuals crossed the U.S. border into Baja California, Mexico. Individuals used shallow habitats (134.96 ± 191.1 m) close to shore (7.16 ± 5.65 km). A generalized linear model with a binomial distribution was used to predict the presence of individuals based on several environmental predictors from these areas. Juveniles were found to select shallow habitats (< 1000 m deep) close to land (< 30 km of the shoreline) in waters ranging from 14 to 24°C. Southern California was found to be suitable eight months of the year, while coastal habitats in Baja California were suitable year-round. The model predicted seasonal movement with sharks moving from southern California to Baja California during winter. Additionally, habitat distribution changed inter-annually with sharks having a more northerly distribution during years with a higher Pacific Decadal Oscillation index, suggesting sharks may forego their annual fall migrations to Baja California, Mexico, during El Niño years. Model predictions aligned with fishery-dependent catch data, with a greater number of sharks being captured during periods and/or areas of increased habitat suitability. Thus, habitat models could be useful for predicting the presence of JWS in other areas, and can be used as a tool for potentially reducing fishery interactions during seasons and locations where there is increased susceptibility of incidental catch.

Gendered dimensions of population mobility associated with HIV across three epidemics in rural Eastern Africa.

Mobility in sub-Saharan Africa links geographically-separate HIV epidemics, intensifies transmission by enabling higher-risk sexual behavior, and disrupts care. This population-based observational cohort study measured complex dimensions of mobility in rural Uganda and Kenya. Survey data were collected every 6 months beginning in 2016 from a random sample of 2308 adults in 12 communities across three regions, stratified by intervention arm, baseline residential stability and HIV status. Analyses were survey-weighted and stratified by sex, region, and HIV status. In this study, there were large differences in the forms and magnitude of mobility across regions, between men and women, and by HIV status. We found that adult migration varied widely by region, higher proportions of men than women migrated within the past one and five years, and men predominated across all but the most localized scales of migration: a higher proportion of women than men migrated within county of origin. Labor-related mobility was more common among men than women, while women were more likely to travel for non-labor reasons. Labor-related mobility was associated with HIV positive status for both men and women, adjusting for age and region, but the association was especially pronounced in women. The forms, drivers, and correlates of mobility in eastern Africa are complex and highly gendered. An in-depth understanding of mobility may help improve implementation and address gaps in the HIV prevention and care continua.

Migratory life cycle of Ephemerella maculata (Traver, 1934) (Ephemerellidae)

In this paper, I describe for the first time the migratory life cycle of an univoltine mayfly, Ephemerella maculata (Traver, 1934), between mainstems and tributaries of stream networks in California. Ephemerella maculata nymphs grow in sunny open mainstems and then emerge. Female adults fly into adjacent shaded tributaries, oviposit eggs, and die. The eggs diapause over summer and hatch in the fall in tributaries; then small nymphs drift down back to the mainstem before the subsequent spring growing season. Isotope analyses validate the adult migrations from mainstem to tributaries. Field rearing experiments show that the abundant algae in sunny mainstems are important food for the growth of E. maculata nymphs. However, eggs survive and hatch equally well in mainstem and tributaries, therefore, the fitness advantage of their migration to tributaries remains unclear.

The importance of embayed coastal areas for the life cycle of two sympatric starfish species (Echinodermata, Asteroidea)

Coastal embayed areas are important sites for many benthic and nektonic organisms that are being increasingly threatened by habitat degradation. The knowledge on the biology of these organisms can reveal the importance of such areas for their life cycles. Furthermore, population information is also imperative to recognize the importance of these species to structure coastal ecosystems and to provide support to management strategies. In this study, we aimed to evaluate the importance of a coastal embayment area for the generalist predator starfish Astropecten marginatus and Luidia senegalensis, analyzing their spatio-temporal distribution and populational parameters and evaluating whether (1) the species present a differential use of the area, (2) the species use the bay for recruitment, growth and reproduction and (3) there is an ontogenetic or gender related variation in the bay occupation. This study was carried out at Caraguatatuba Bay (SE Brazil), with monthly samples from July/03 to October/04. Although Astropecten was more abundant than Luidia, the two species had similar shifts in abundance, with peaks during cold/dry months, which are partly related to recruitment patterns. Species were distributed mainly towards the southern area of the bay, where A. marginatus had denser aggregations. Both species used the bay for recruitment, growth and reproduction. Males and females of both species occurred in similar numbers (sex ratio 1:1), except in late autumn (May-June) when females became more numerous. An annual reproductive cycle was observed for both species, with spawning occurring mainly in the rainy season, and recruitment mainly during fall/winter. Large individuals (>17 cm) of L. senegalensis were sub-represented in the bay, indicating possible adult migration to deeper areas, whereas A. marginatus had a more resident behavior. Distribution of both species correlated well with diet information previously available, with prey-partitioning suggested as a mechanism that allow their similar occupation of the area, and ontogenetic diet shifts explaining the adult migration of L. senegalensis. This highlights the relevance of feeding information to predict distribution of starfish. Our results elucidate the importance of the studied bay for the life cycle of these keystone species, elucidating species-specific vulnerabilities to coastal degradation and the importance of recognizing populational and distribution parameters in order to inform management policies.

The contribution of road‐based citizen science to the conservation of pond‐breeding amphibians

AbstractRoadside amphibian citizen science (CS) programmes bring together volunteers focused on collecting scientific data while working to mitigate population declines by reducing road mortality of pond‐breeding amphibians. Despite the international popularity of these movement‐based, roadside conservation efforts (i.e. “big nights,” “bucket brigades” and “toad patrols”), direct benefits to conservation have rarely been quantified or evaluated.As a case study, we used a population simulation approach to evaluate how volunteer intensity, frequency and distribution influence three conservation outcomes (minimum population size, population growth rate and years to extinction) of the spotted salamander (Ambystoma maculatum), often a focal pond‐breeding amphibian of CS and conservation programmes in the United States.Sensitivity analysis supported the expectation that spotted salamander populations were primarily recruitment‐driven. Thus, conservation outcomes were highest when volunteers focused on metamorph outmigration as opposed to adult in‐migration—contrary to the typical timing of such volunteer events.Almost every volunteer strategy resulted in increased conservation outcomes compared to a no‐volunteer strategy. Specifically, volunteer frequency during metamorph migration increased outcomes more than the same increases in volunteer effort during adult migration. Small population sizes resulted in a negligible effect of volunteer intensity. Volunteers during the first adult in‐migration had a relatively small effect compared to most other strategies.Synthesis and applications. Although citizen science (CS)‐focused conservation actions could directly benefit declining populations, additional conservation measures are needed to halt or reverse local amphibian declines. This study demonstrates a need to evaluate the effectiveness of focusing CS mitigation efforts on the metamorph stage, as opposed to the adult stage. This may be challenging, compared to other management actions such as road‐crossing infrastructure. Current amphibian CS programmes will be challenged to balance implementing evidence‐based conservation measures on the most limiting life stage, while retaining social and community benefits for volunteers.

Partial migration and early size of southern hake Merluccius australis: a journey between estuarine and oceanic habitats off Northwest Patagonia

AbstractPartial migration is a key adaptive strategy, increasingly observed across multiple taxa. To investigate partial migration and life-cycle diversity of Merluccius australis in northwestern Patagonia, we analysed isotopic (δ13C, δ18O) and elemental (11B, 23Na, 24 Mg, 55Mn, 86Sr, 138Ba) compositions of otoliths from juveniles, sub-adults, and adults to identify nursery origins, habitats used, and migratory behaviours of multiple cohorts (1990–2005). Influence of early size upon migration was assessed by comparing back-calculated sizes at demersal recruitment between resident and migratory adults. Although partial migration occurred at both estuarine and oceanic nursery habitats, migratory behaviour was more frequent in fish of estuarine origin (59%) than in fish of oceanic origin (17%). Adults of estuarine origin dominated both estuarine (92%) and oceanic (77%) sampling areas. Although we found no significant differences in size at demersal recruitment between oceanic-resident and oceanic-migratory fish, a strong relationship between size at demersal recruitment and migratory behaviour appeared in fish of estuarine origin, whose probability of migration increased from 5% to 95% as demersal recruitment size increased from 18.8 to 23.6 cm. Further research on M. australis life cycle is required to incorporate sub-population processes into the stock assessment and management models being used for this overexploited species.

Anthropogenic habitat alteration leads to rapid loss of adaptive variation and restoration potential in wild salmon populations

Phenotypic variation is critical for the long-term persistence of species and populations. Anthropogenic activities have caused substantial shifts and reductions in phenotypic variation across diverse taxa, but the underlying mechanism(s) (i.e., phenotypic plasticity and/or genetic evolution) and long-term consequences (e.g., ability to recover phenotypic variation) are unclear. Here we investigate the widespread and dramatic changes in adult migration characteristics of wild Chinook salmon caused by dam construction and other anthropogenic activities. Strikingly, we find an extremely robust association between migration phenotype (i.e., spring-run or fall-run) and a single locus, and that the rapid phenotypic shift observed after a recent dam construction is explained by dramatic allele frequency change at this locus. Furthermore, modeling demonstrates that continued selection against the spring-run phenotype could rapidly lead to complete loss of the spring-run allele, and an empirical analysis of populations that have already lost the spring-run phenotype reveals they are not acting as sustainable reservoirs of the allele. Finally, ancient DNA analysis suggests the spring-run allele was abundant in historical habitat that will soon become accessible through a large-scale restoration (i.e., dam removal) project, but our findings suggest that widespread declines and extirpation of the spring-run phenotype and allele will challenge reestablishment of the spring-run phenotype in this and future restoration projects. These results reveal the mechanisms and consequences of human-induced phenotypic change and highlight the need to conserve and restore critical adaptive variation before the potential for recovery is lost.

Local adaptation of phenology revealed in outcrosses between spawning segments of a salmonid population

Local adaptation has been demonstrated in spatially or temporally distant animal populations but seldom in proximate populations. To address the scale of local adaptation in Pacific salmon (Oncorhynchus spp.), two generations of hybrids between temporally separated spawning segments were made in a population of pink salmon (O.gorbuscha) and compared with controls to evaluate the genetic architecture underlying adult migration time and to test for declines in marine survival that resulted from outbreeding depression. Bayesian mixed-effects models revealed that adult migration times in hybrid lines were intermediate to those of controls and that additive sources of genetic variation were significant, thereby indicating that local adaptation has acted on additive genetic variation in shaping this trait. Similarly, a line cross analysis revealed that an additive model best described the genetic architecture of adult migration time. In contrast, marine survival was generally similar between control and hybrid lines, which suggested that the effect of outbreeding upon marine survival was minimal at such a fine scale of genetic divergence. The implications of these results are that (a) local adaptation can facilitate genetic divergence of life history traits between proximate subpopulations; (b) artificial relaxation of natural barriers to gene flow can cause maladaptive shifts in life history traits; and (c) wild populations may harbour fine-scale adaptive variation that supports productivity and sustainability.

Negotiating Life in Times of Crisis: The Transnational Return Migration of Refugee Adolescents and Young Adults from Germany to the Kurdistan Region of Iraq

In this article, the concept of transnational migration serves as a foundation for analyzing the perspectives of children and adolescents on family movements of migration, their transnational practices, and their sense of belonging. The article discusses, on the basis of a case study, the critical situations children and young people encounter in the context of transnational migration and education. Drawing on Lorenzer’s methodology of hermeneutical cultural analysis, the researcher conducted a set of interviews with refugee children, adolescents, and young adults who have returned with their families from Germany to Iraqi Kurdistan. The article shows that, in light of the conflicts arising for the interviewees in the experience of transnational return, a special emphasis on education can aid their integration into the new society.

Delayed timing of successful spawning of an estuarine dependent fish, black bream Acanthopagrus butcheri.

In this paper, we investigate the period of successful spawning for black bream Acanthopagrus butcheri, an obligate estuarine species in southern Australia that typically spawn in spring and early summer. However, back-calculated spawning dates of juveniles sampled in Gippsland Lakes, Victoria from February to May 2016 indicated that spawning was concentrated over a short period in the Austral mid-summer (January), with a second spawning in late summer and early autumn (late February-early March). Ichthyoplankton sampling in the tributary estuaries from October to early December collected substantial numbers of fish larvae, dominated by gobiids, eleotrids and retropinnids of freshwater origin, but no A. butcheri. The lack of A. butcheri larvae was consistent with the delayed successful spawning indicated by juvenile otolith data. Freshwater flows declined from late winter to summer, with consistent salinity stratification of the water column. Dissolved oxygen (DO) concentrations were generally very low below the halocline. These conditions may have delayed the upstream spawning migration of adults or may have been unsuitable for survival of eggs and newly-hatched larvae. Longer-term predictions for climate change in southern Victoria, including the Gippsland Lakes region, are for lower winter-spring freshwater flows, potentially benefiting the reproductive success of A. butcheri through high water-column stratification, but only if DO concentrations are not compromised by a lack of high winter flows needed to flush low DO water from the system.

Evaluating flow management as a strategy to recover an endangered sturgeon species in the Upper Missouri River, USA

AbstractIn the Upper Missouri River, Fort Peck and Garrison Dams limit the length of free‐flowing river available to the endangered pallid sturgeon. These barriers restrict the upstream migration of adults and downstream larval dispersal. A one‐dimensional (1D) modelling framework is currently in use to evaluate reservoir operation alternatives and to simulate drift of dispersing free embryos for different flow regimes and reservoir stages. This paper presents the results of a large‐scale tracer experiment conducted in 2016 and associated modelling performed to evaluate flow management scenarios that might aid species recovery. Breakthrough curves from the tracer experiment were used to infer the 1D longitudinal dispersion coefficient from a parameter optimization procedure. Simulations generated using the calibrated 1D advection–dispersion model were compared with field observations of the passive tracer and with larval fish collected during a previous experiment in 2007. When used with the appropriate range of dispersion coefficients, the 1D modelling framework agrees well with the available direct measurements of larval drift distances. Although we cannot unequivocally state whether insufficient length of free‐flowing river alone is causing recruitment failure, given the current thermal regime and our understanding of pallid sturgeon development, the time required for pallid sturgeon to transition to the benthos and initiate feeding might exceed the duration of drift available given constraints of reservoir operations.

Living Arrangements, Offspring Migration, and Health of Older Adults in Rural China: Revelation From Biomarkers and Propensity Score Analysis

Objective: We examine the combined effects of living arrangements and outmigration of adult children on rural older adults' health profiles, measured by biomarker data from the China Health and Retirement Longitudinal Study 2011. Method: We employ biomarker data and propensity score analysis which allows us to effectively deal with selection issues that are commonly observed in the literature. Results: We show complex health implications of living arrangements and offspring migration. Living in a traditional multigenerational household has limited health benefits to older adults. However, older parents of migrants who live in a multigenerational household have better fitness in blood pressure. Their advantage over parents of migrants in other living arrangements suggests added benefits of the presence of grandchildren. Discussion: This study bridges the living arrangement and migration literature on health by showing that health effects of adult children's migration on older adults are contingent upon their living arrangements.

Coho Salmon Colonization of Oregon's Upper Willamette River Basin

Coho Salmon Oncorhynchus kisutch were historically absent from a major Columbia River subbasin, the upper Willamette River (UWR), until a fishway was installed at Willamette Falls and a sustained stocking program was implemented in the 1950s. Despite decades of stocking from three diverse source populations (early run, late run, and coastal Coho Salmon) during the second half of the twentieth century, adult abundance above the falls was less than 1,000 annually during the 1990s. A recent surge (>25,000 adults in 2009) has raised concerns about potential interactions with two native anadromous salmonids listed under the U.S. Endangered Species Act: UWR winter-run steelhead O. mykiss and UWR spring-run Chinook Salmon O. tshawytscha. We analyzed Coho Salmon stocking records and estimates of abundance from 1954–2017 to summarize population history, demographics, and adult phenology. We also characterized current Coho Salmon distribution using radiotelemetry (n = 219 adults in 2014) and evaluated potential mechanisms associated with changes in adult abundance. We identified a shift in adult migration timing over the time series that was consistent with an increase in late-run traits and environmental changes affecting migration cues. The distribution of radio-tagged adults among UWR subbasins was only weakly correlated with past stocking efforts, suggesting that habitat conditions, stocked phenotype, adaptation and range expansion by descendants of the relict stocked populations, or colonization from regional source populations strongly influenced current subpopulation abundance. Annual counts of returning UWR Coho Salmon were positively correlated with counts of Columbia River Coho salmon, suggesting a shared response to freshwater habitat or ocean conditions. Regardless of the underlying mechanisms affecting UWR Coho Salmon distribution and population size, the results illustrate the complex dynamics between changing landscapes and migration corridors, the introduction of nonnative species for harvest management goals, and the potential for nonnative fish to affect the conservation of native populations.

Genome-wide divergence patterns support fine-scaled genetic structuring associated with migration tendency in brown trout

Brown trout (Salmo trutta) exhibit highly diverse life histories varying from resident, slow-growing, and early maturing to migratory, fast-growing, and late maturing, even within single watersheds. We sampled 11 locations within the transboundary Finnish–Russian River Koutajoki watershed to evaluate genomic differences among mainstem and headwater sites, of which some are isolated by migration barriers. Restriction site associated sequencing (RADSeq) revealed that the most headwater localities supported unique, isolated populations with generally lower heterozygosity compared with the mainstem populations. The sampled migratory adults in the three main stems showed signals of admixture despite small but statistically significant genetic divergence, while the headwater populations, except for two, showed a high level of divergence and a lack of admixture. These results suggest that most of the headwater populations consist of resident brown trout and that the population genetic structuring is often maintained even in the absence of migration barriers. Our results have clear implications for fisheries management and conservation; each brown trout subpopulation represents an evolutionarily important unit with unique genetic makeup and life history variation.

Genetic structure and demographic connectivity of marbled flounder (Pseudopleuronectes yokohamae) populations of Tokyo Bay

Marine populations are generally well connected through larval exchange, and juvenile and adult migration. Genetic differentiation and/or local adaptation among populations are sometimes observed at small spatial scales. The marbled flounder (Pseudopleuronectes yokohamae) is a commercially important coastal species in Tokyo Bay, Central Japan, exhibiting different spawning phenology at a small scale. Using 30 highly polymorphic microsatellite loci, including the 16 new microsatellite loci developed in the present study, we estimated the genetic structure and demographic connectivity of specimens collected along Tokyo Bay in 2012–2013 and 2015–2016. F-statistics indicated a genetic differentiation between adult populations collected within and outside Tokyo Bay during both collection periods, but almost no difference was detected between the populations from the inner and outer parts of Tokyo Bay. Assignment tests directly estimated demographic connectivity between the inner and outer bays via larval dispersal and juvenile and adult migration. The average movement distance of marbled flounder was 13.1–29.6 km, with a maximum distance of 42.8–54.0 km. This movement distance contributed to the strong demographic connectivity between the inner and outer bays. Meanwhile, an indirect method using the isolation by distance (IBD) theory underestimated the average movement distance (5.0–7.8 km) because the isolated setting of Tokyo Bay resulted in a higher IBD slope. Based on the results of F-statistics and assignment tests, we suggest that a multilayered management by local and regional organizations may benefit the fishery in Tokyo Bay.

Near-future temperature reduces Mg/Ca ratios in the major skeletal components of the common subtropical sea urchin Lytechinus variegatus

Shallow-water marine invertebrates living near the upper limits of their thermal tolerances are uniquely susceptible to climate warming. This is particularly the case for species that occur in geographic regions where larval dispersal or adult migration to cooler waters is not an option. This scenario aptly describes populations of the seagrass-associated sea urchin Lytechinus variegatus inhabiting the northern Gulf of Mexico where northward movement is restricted by a coastline. In the present study, we exposed juvenile L. variegatus to chronic ambient (26 °C) and predicted near-future (30 °C) temperature treatments for 90 days. X-ray Diffraction (XRD) was employed to determine the Mg/Ca ratios of the spines, test, and Aristotle's lantern of individuals sub-sampled at 30, 60, and 90 days. We found that while individuals grew at similar rates, Mg/Ca ratios in all skeletal components were overall significantly lower in individuals held at 30 °C than at 26 °C.

Biophysical connectivity of snapper spawning aggregations and marine protected area management alternatives in Cuba

AbstractThe ability of larvae to move beyond the spatial range of adult migrations can be critical to the resilience of populations that aggregate to spawn. We reviewed the literature and unpublished information on larval transport modeling, reef fish spawning aggregations, and marine protected area (MPA) management to identify alternatives for Cuban spawning site conservation. Larval transport information is available at annual and decadal scales for eight Cuban sites for five species of snappers. Connectivity patterns were examined: (a) within Cuban regions, (b) among Cuban regions, and (c) among other countries. We compared this information with the distribution of protected areas relative to spawning sites, site management attributes, and potential alternatives. Of eight focal spawning sites, seven are in protected areas and one is proposed. Southeast and north‐central Cuba had highest estimated within‐region retention levels. Southwest and northwest sites exported relatively more larvae out‐of‐region. Southern regions produced larvae that reached Jamaica, the Cayman Islands and Haiti. All northern regions can export larvae to the southern Bahamas. The regions and sites within are geomorphologically diverse with variable fishing and socio‐economic attributes. Information on stock status and protected area efficacy is limited and field assessments of aggregation status are needed for multispecies spawning sites. Few management plans address spawning conservation or network connectivity opportunities for MPAs. An alternative is development of one or more regional workgroups of protected area specialists, fishery scientists, expert fishers, and other stakeholders. Temporal closures of fisheries before and during spawning season could also amplify effectiveness of current gear‐ and zoning‐based management tools.

Genomics and conservation units: The genetic basis of adult migration timing in Pacific salmonids.

It is now routinely possible to generate genomics‐scale datasets for nonmodel species; however, many questions remain about how best to use these data for conservation and management. Some recent genomics studies of anadromous Pacific salmonids have reported a strong association between alleles at one or a very few genes and a key life history trait (adult migration timing) that has played an important role in defining conservation units. Publication of these results has already spurred a legal challenge to the existing framework for managing these species, which was developed under the paradigm that most phenotypic traits are controlled by many genes of small effect, and that parallel evolution of life history traits is common. But what if a key life history trait can only be expressed if a specific allele is present? Does the current framework need to be modified to account for the new genomics results, as some now propose? Although this real‐world example focuses on Pacific salmonids, the issues regarding how genomics can inform us about the genetic basis of phenotypic traits, and what that means for applied conservation, are much more general. In this perspective, we consider these issues and outline a general process that can be used to help generate the types of additional information that would be needed to make informed decisions about the adequacy of existing conservation and management frameworks.