Hudson River Research Articles

Shifting spawning phenology in Hudson River American Shad

AbstractObjectiveThe objectives of this study were to investigate potential shift in the phenology of spawning for the Hudson River American Shad Alosa sapidissima and to identify factors contributing to the decline of the Hudson River shad population.MethodsThis study utilized American Shad eggs collected from the Long River Ichthyoplankton Survey. Logistic models were employed to estimate spawning phenology metrics, including the onset, peak, cessation, and duration of the spawning season. Additionally, we investigated the effects of biotic and abiotic variables on spawning timing.ResultThis study suggests that temporal changes in the spawning onset exhibited high variation and were not significant. However, a significantly delayed spawning peak and cessation, along with an extended spawning season, were observed. Additionally, the findings of this study revealed a correlation between the timing of spawning onset and water temperature, indicating that a 1°C increase in water temperature was associated with a 3.66‐day earlier initiation of spawning. Smaller female spawner size was associated with delayed peak and cessation of the spawning season. With a 1‐cm decrease in the average female spawner size, the peak of the spawning season was delayed by 1.79 days and the cessation of the spawning season was delayed by 2.87 days.ConclusionThe findings indicate that water temperature may be a crucial trigger for initiating spawning in Hudson River American Shad, with higher water temperatures associated with earlier spawning onset. Moreover, the findings indicate that the timing of spawning peaks and cessations has been progressively delayed over time, and this is linked to the size of female spawners.

Biomineralization and biomechanical trade-offs under heterogeneous environments in the eastern oyster Crassostrea virginica

ABSTRACT Accurate biological models are critical to reliably predict vulnerability of marine organisms and ecosystems to rapid environmental changes. Current predictions on the biological impacts of climate change and human-caused disturbances primarily stem from controlled experiments but lack assessments of the mechanisms underlying biotic variations in natural systems, especially for habitat-forming, climate-sensitive species with key ecological roles. This study aimed to characterize and quantify spatial patterns of shell biomineralization and biomechanical properties in a key reef-building oyster, Crassostrea virginica, collected from restored reefs along natural estuarine gradients in the Hudson River Estuary (NY, USA). We characterized patterns of oyster shell deposition, structure, composition and mechanical performance at the macro- and microscale. Eastern oysters show a strong capacity for adjustments in shell biomineralization and biomechanics to maintain shell production and protective functions. We reveal salinity as a key predictor of oyster shell structure, mechanical integrity and resistance to dissolution, and describe the functional role of chalky calcite in shaping shell mechanical performance. Changes in shell production along salinity gradients indicate formation of shells with (1) high mechanical resistance but increased vulnerability to dissolution under marine conditions and (2) lower structural integrity but higher protection from dissolution under brackish conditions. Our work illustrates that biomineralization and biomechanical trade-offs may act as mechanisms in eastern oysters to maintain overall performance under heterogeneous estuarine environments and could represent a cornerstone for calcifying organisms to acclimate and maintain their ecological functions in a rapidly changing climate.

The Importance of Capacity-Building in Watershed Groups: Lessons from the Hudson River Watershed, USA.

Municipalities face challenges meeting environmental protection and conservation goals due to a lack of resources, capacity, and political will. As a result, grassroots environmental organizations often emerge to help meet these challenges by filling gaps in governmental operation and structure. At the watershed scale, environmental organizations and groups are critical for effective watershed governance, often helping with collaboration as well as providing municipalities with additional support and resources. Despite the vital role environmental organizations and groups can play, they continue to face challenges such as insufficient resources, inconsistent leadership, and lack of organizational structure, thus limiting the contributions they can deliver. In this manuscript, we present case study research on watershed groups exploring their capacity to meet their mission and goals. Drawing from a needs assessment study conducted in the Hudson River watershed in 2019-2021, we found that while watershed groups are generally in need of technical resources, participation, and funding, our research suggests capacity (such as internal structure, strategic planning, and leadership) is most important for successful and sustainable groups. Therefore, we argue that support for capacity is more likely to help sustain groups and their long-term beneficial impact. To make this argument we present qualitative interview and focus group data to articulate watershed group goals, challenges, and needs, with an emphasis on capacity-related themes that emerged around expertise, leadership, structure, and planning. We then conclude with recommendations that can be applied to other watershed groups in the United States, and likely beyond.

Awareness and compliance with fish consumption advisories on the upper Hudson River Superfund Site

Awareness and compliance with fish consumption advisories on the upper Hudson River Superfund Site

Development of a Spectrum-Based Scheme for Simulating Fine-Grained Sediment Transport in Estuaries

Fine-grained cohesive sediments in estuaries play a critical role in sediment transport and biogeochemical cycles in estuaries. Due to the convergence of marine saltwater and freshwater runoff, combined with periodic tidal cycles, fine-grained sediments exhibit intricate flocculation processes that are challenging to simulate. A size-resolved flocculation module using a bin-based scheme aids in modeling these processes but is hindered by high computational costs. In this study, we develop a new spectrum-based scheme based on the spectral shape of floc size distribution from the original bin-based scheme to expedite modeling execution. This new scheme is implemented in the Stony Brook Parallel Ocean Model (sbPOM) and applied to simulate fine-grained sediment transport in the Hudson River estuary. The effectiveness of this spectrum-based scheme is assessed by comparing its simulations with observations and results from the original bin-based scheme. The findings indicate that the new scheme can simulate the evolution of suspended sediment concentration well at a specific point by comparisons with in-situ observations. Specifically, the results of the 50 paired experiments show an average percentage difference of 1.86% and an average speedup ratio of 4.51 times compared to the original bin-based scheme. In summary, the new spectrum-based scheme offers significant acceleration benefits for the size-resolved flocculation module and has the potential for widespread application in simulating fine-grained sediments in estuaries.

Climate Change and the Hudson River Marshlands

Climate Change and the Hudson River Marshlands

Spatial and temporal variability of water transparency, its primary drivers, and other optical properties in the Hudson River Estuary

Water transparency, measured as the diffuse attenuation coefficient of photosynthetically-active (400–700 nm) radiation, KdPAR, was measured monthly from May–Oct 2020 at 73 locations along 250 km of the Hudson River estuary (HRE) between New York City, NY and Waterford, NY. Three primary optical drivers of KdPAR variability: chlorophyll concentration (CHL), turbidity, and light absorption by colored dissolved organic matter (aCDOM), were measured concurrently to assess their relative importance to spatial and temporal KdPAR patterns. KdPAR was higher and more variable in the brackish HRE relative to limnetic regions further north. KdPAR was also significantly higher nearshore and near sewage treatment plant outfalls relative to midchannel sites. Temporal variability at individual stations was generally lower than cross-channel or cross-region spatial variability. Turbidity was the most important factor in KdPAR variability in all regions of the HRE, followed by CHL, with aCDOM playing a lesser role. Although many water quality variables have changed in the HRE over recent decades, KdPAR measurements in the brackish regions overlapped with published observations from the 1970s–1990s. KdPAR in the limnetic regions was lower in 2020 than measurements made prior to the Zebra mussel invasion in the early 1990s, but similar to measurements in the limnetic regions made since the invasion. Results of this study can be used to optimize satellite-based remote sensing algorithms for synoptic water quality observations of the HRE. Proposed future alterations in the HRE, including dredging and the construction of storm-surge barriers, would likely change existing KdPAR patterns. This study therefore provides an updated baseline for optical parameters in the HRE and highlights the importance of understanding the impacts of any proposed alterations to upper-water-column turbidity in this system. Results also demonstrate that KdPAR, euphotic depths, and Secchi depth measurements were positively correlated throughout the HRE. Secchi depth measurements may therefore be useful for additional retrospective studies, and future monitoring (including by satellite-derived KdPAR) of water transparency in the HRE.

Population Responses of Blueback Herring to Dam Passage Standards and Additive Mortality Sources

Abstract The management of anadromous fishes is inherently complicated as this suite of species exhibits complex life-histories in multiple habitats and is subject to varying natural and anthropogenic influences during discrete ontogenetic periods. Life-history based simulation models have been increasingly adopted by fishery scientists and managers to help understand potential effects of management decisions on fish populations while incorporating uncertainty in life-history, climate, and other components of resource management systems. We applied one such model to Blueback Herring Alosa aestivalis in the Hudson River watershed, NY, USA. Our goal was to better understand influences of historical habitat loss on anadromous fishes and determine to what extent and under what conditions novel habitat created by canal infrastructure might confer increased population abundance. We found that access to historical habitat in the upper Hudson River increased population abundance at all upstream dam passage rates with sufficient downstream survival of adult and juvenile Blueback Herring, but that abundance decreased with increasing upstream passage relative to the “no passage” scenario when downstream survival through dams was not sufficiently high. Access to novel spawning habitat in the Mohawk River canal system resulted in increased abundance of Blueback Herring when downstream survival of adults and juveniles was at least 0.80 per dam and both upstream passage and probability of using the Mohawk River were both greater than about 0.25. Both mortality during upstream passage of locks in the Mohawk River and marine fishery mortality had the potential to reduce Blueback Herring abundance below historical population abundance despite access to novel spawning habitat. These results highlight the complexity associated with effects of upstream and downstream fish passage standards on population responses while emphasizing similarities observed in other diadromous species and watersheds.

The Impact of Combined Sewer Overflows on Pharmaceutical and Illicit Drug Levels in New York/New Jersey Waterways.

Pharmaceuticals and drugs of abuse are organic micropollutants of emerging concern in both surface and groundwater worldwide. These compounds are considered to be pseudo-persistent because of their continuous release into water systems. The presence of these compounds in the environment at any concentration poses a potential risk to nontarget organisms. The main sources of these contaminants are wastewater treatment plants (WWTPs) and combined sewer overflows (CSOs). The primary goal of our study was to identify and quantify a panel of 28 commonly prescribed pharmaceuticals (mood-altering drugs, cardiovascular drugs, antacids, antibiotics) and high-prevalence drugs of abuse (cocaine, amphetamines, opioids, cannabis) in river water samples collected from 19 locations in the Hudson and East rivers in New York City. The second goal was to investigate the possible source (WWTP or CSOs) of these micropollutants. Samples were collected weekly from May to August 2021 (n = 224) and May to August 2022 (n = 232), and placed at -20 °C until analysis by liquid chromatography-tandem mass spectrometry. The most frequently detected analytes in 2021 were metoprolol (n = 206, 92%), benzoylecgonine (n = 151, 67%), atenolol (n = 142, 63%), and methamphetamine (n = 118, 53%), and in 2022 the most frequently detected were methamphetamine (n = 194, 84%), atenolol (n = 177, 76%), metoprolol (n = 177, 76%), and 2-ethylene-1,5-dimethyl-3,3-diphenylpyrrolidine (n = 159, 69%). Measured concentrations ranged from the limit of detection (0.50-5.00 ng/L) to 103 ng/L. More drugs and higher concentrations were detected in water contaminated by Enterococci (>60 most probably number) and after rainfall, indicating the influence of CSOs. The presence of drugs in samples with little to no Enterococci and after dry weather events indicates that WWTPs contribute to the presence of these substances in the river, probably due to a low removal rate. Environ Toxicol Chem 2024;43:1592-1603. © 2024 SETAC.

Matching field-based ranges in brackish water gradients with experimentally derived salinity tolerances of Conrad’s false mussel (Mytilopsis leucophaeata cochleata) and zebra mussel (Dreissena polymorpha)

The invasive alien false mussels Mytilopsis leucophaeata cochleata and Dreissena polymorpha (Dreissenidae) have established populations in the North Sea canal in the Netherlands that connects the harbours of Amsterdam with the North Sea. The favourable and unfavourable salinity ranges of both species were earlier studied in long-term outdoor mesocosm experiments. Their occurrence in salinity gradients in estuaries or canals connecting seaways to freshwater harbours provides information on their salinity tolerance under field conditions. By the combination of laboratory experiments and field data using the same source population a high predictability can be expected for establishment of the gradients facilitated by constructions. The reliability of experimentally derived salinity-tolerance limits for both dreissenid species was tested using data on their distribution in a salinity gradient of the littoral zone along the North Sea canal. The mussels used for the survival experiments in mesocosms were also collected from this canal. Favourable salinity ranges for adult survival in the mesocosms were 0.2 – 17.5 for M. leucophaeata cochleata and 0.2 – 6.0 for D. polymorpha. Unfavourable salinities were outside these ranges and led to high and fast mortality of these species. Mytilopsis leucophaeata cochleata was present over nearly the whole length of the North Sea canal with the highest densities close to the sea sluices where also the highest salinities and water temperatures were measured. Their densities in the canal decreased gradually at larger distances from the sea. Dreissena polymorpha co-exists with M. leucophaeata cochleata at the east end of the canal with low salinity due to the influence of freshwater of the river Rhine. The occurrence of D. polymorpha was restricted to a salinity below 4 and M. leucophaeata cochleata only occurred at a salinity above 1.5 (maximum value measured in the canal 9.2). Shorter salinity gradients with lower salinity ranges provided additional information on the co-existence of both species. Co-existence was observed at a salinity range of 1.5–3.3 (own data), 1.0–3.5 (Van Couwelaar and Van Dijk 1989), both in the North Sea canal, and 0.2–2.8, in the Canal through Voorne (Janssen and Janssen-Kruit 1967). These data correspond with studies of both species by Walton (1996) in the Hudson River (salinity range 0–3). Found salinity ranges in the North Sea canal for both species match with the tolerance results obtained by mesocosm experiments. A new invading dreissenid mussel Dreissena rostriformis bugensis and a mytilid Ischadium recurvum occur in the North Sea canal since 2006 and 2012, respectively. Competition between recent and earlier invaders is likely when salinity tolerances are similar. It has already been observed that D. rostriformis bugensis outcompetes D. polymorpha under freshwater conditions (Bij de Vaate et al. 2014; Matthews et al. 2014). Ischadium recurvum has the potential to colonize large parts of the canal and to be a strong competitor of M. leucophaeata cochleata (Goud et al. 2019). Since January 2022, the new ‘Zeesluis IJmuiden’ with the biggest locks in the world is in use, affecting the probability of population establishment of new introduced and invasive alien mussel species.

Henry Hun and his family: Three foundational stories in the history of nineteenth-century American neurology, Part I. Thomas Hun (1808–1896): Nineteenth-century patriarch, neurophilosopher, and proto-neurologist

ABSTRACT Thomas Hun (1808–1896)—along with his sons Edward (1842–1880) and Henry (1854–1924)—were prime movers in establishing the clinical practice and academic discipline of neurology in the Hudson River Valley of New York in the ninteenth and early-twentieth centuries. This article outlines the life of the family’s semi-aristocratic patriarch, beginning with Thomas’s unusual educational background and his six-year post-graduate hiatus in Paris of the 1830s, where he came under the influence of P. C. A. Louis (1787–1872). It lays out his subsequent career as professor of the Institutes of Medicine and ultimately as dean of an American medical school that was not situated in a major metropolis. It also will demonstrate how Thomas Hun’s career as a medical practitioner, academician, neurophilosopher, and “proto-neurologist” recapitulates the evolution of clinical and academic neurology in nineteenth-century America.

Spatiotemporal patterns in habitat use of natal and non-natal adult Atlantic sturgeon in two spawning rivers

BackgroundMonitoring movement across an organism’s ontogeny is often challenging, particularly for long-lived or wide-ranging species. When empirical data are unavailable, general knowledge about species’ ecology may be used to make assumptions about habitat use across space or time. However, inferences about habitat use based on population-level ecology may overlook important eco-evolutionary contributions from individuals with heterogenous ethologies and could diminish the efficacy of conservation and management.MethodsWe analyzed over a decade of acoustic telemetry data to understand individual differences in habitat use of federally endangered adult Atlantic sturgeon (Acipenser o. oxyrinchus) in the Delaware and Hudson rivers during spawning season. In particular, we sought to understand whether sex or natal origin could predict patterns in habitat use, as there is a long-held assumption that adult Atlantic sturgeon seldom stray into non-natal rivers.ResultsIn both rivers, migration timing, spawning habitat occupancy, and maximum upstream migration distance were similar between natal and non-natal individuals. While non-natal individuals represented only 13% of fish detected in the Hudson River, nearly half of all tagged fish detected in the Delaware River were non-natal and generally occupied freshwater habitats longer than natal individuals. In both systems males had more heterogenous patterns of habitat use and longer duration of occupancy than did females.ConclusionsThis study demonstrates the importance of non-natal rivers for fulfilling ontogenetic habitat requirements in Atlantic sturgeon. Our results may also highlight an opportunity to improve conservation and management by extending habitat designations to account for more heterogenous patterns in individual habitat use in non-natal freshwater environments.

Differences in life history patterns of American shad (Alosa sapi dissima) populations between ancestral, Atlantic coast, and non-native Pacific coast rivers of North America

Organisms naturalized outside their native range can reveal new life history patterns in new environments. Here, we compare life history patterns of American shad, Alosa sapidissima, from five rivers along the U.S. Pacific coast (introduced range) with contemporary data from the Atlantic coast source populations. The Pacific coast fish grew slower, matured at a younger age, and were less often iteroparous than conspecifics from the Hudson River and Susquehanna River sources. Differences among the Pacific coast populations indicated that some combination of phenotypic plasticity and genetic adaptation has occurred since the transplants in the 1870s. Microchemical analysis of otoliths from returning adults demonstrated an immature, extended freshwater life history form, locally known as “mini-shad”. These fish remain in the river for at least 1 year or enter salt water briefly and then return to fresh water for several months prior to subsequent seaward migration and return as adults. This and other forms of variation (extent of estuary use and size at sea water entry) expand the understanding of Alosine migration and life history diversity.

Early growth and environmental conditions control partial migration of an estuarine-dependent fish

Partial migration is a widespread phenomenon in animals, whereby multiple groups follow different migration behaviors (i.e. contingents) within a single population. Fishes exhibit particularly high diversity in their early dispersal behaviors; however, whether these represent conditional partial migration behaviors remains unclear. We combined otolith microstructure and chemistry to assess the influence of early life conditions and environmental drivers on juvenile-stage partial migration of anadromous striped bass Morone saxatilis in the Hudson River (USA) in 2 consecutive years with contrasting hydrologic conditions. Time series clustering on otolith strontium (Sr) and barium (Ba) profiles revealed 4 dominant early migration contingents in both years: freshwater residents, oligohaline migrants, small mesohaline migrants, and large mesohaline migrants. In both years, juvenile partial migration appeared to be a conditional strategy linked to a growth-mediated threshold. The propensity to migrate early was related to slower larval growth, whereas freshwater residency and delayed migration were associated with faster larval growth. Differences in hatch dates may have indirectly affected migration contingents by exposing larvae to varying environmental conditions. In the dry year, dispersal timing to mesohaline habitats coincided with high freshwater flow and tidal currents, but not so in the higher-flow year. Recruitment to coastal nurseries outside the Hudson River occurred primarily during the juvenile phase. Early migration contingents could carry over to population dynamics, whereby diverse estuarine nursery habitats contribute differently to recruitment.

Curves, Coriolis, and Cross-Channel Circulation in the Hudson River Estuary

Abstract Despite its relatively small magnitude, cross-channel circulation in estuaries can influence the along-channel momentum balance, dispersion, and transport. We investigate spatial and temporal variation in cross-channel circulation at two contrasting sites in the Hudson River estuary. The two sites differ in the relative strength and direction of Coriolis and curvature forcing. We contrast the patterns and magnitudes of flow at the two sites during varying conditions in stratification driven by tidal amplitude and river discharge. We found well-defined flows during flood tides at both sites, characterized by mainly two-layer structures when the water column was more homogeneous and structures with three or more layers when the water column was more stratified. Ebb tides had generally weaker and less definite flows, except at one site where curvature and Coriolis reinforced each other during spring tide ebbs. Cross-channel currents had similar patterns, but were oppositely directed at the two sites, demonstrating the importance of curvature even in channels with relatively gradual curves. Coriolis and curvature dominated the measured terms in the cross-channel momentum balance. Their combination was generally consistent with driving the observed patterns and directions of flow, but local acceleration and cross-channel advection made some notable contributions. A large residual in the momentum balance indicates that some combination of vertical stress divergence, baroclinic pressure gradients, and along-channel and vertical advection must play an essential role, but data limitations prevented an accurate estimation of these terms. Cross-channel advection affected the along-channel momentum balance at times, with implications for the exchange flow’s strength. Significance Statement Currents that flow across the channel in an estuary move slower than those flowing along the channel, but they can transport materials and change water properties in important ways, affecting human uses of estuaries such as shipping, aquaculture, and recreation. We wanted to better understand cross-channel currents in the Hudson River estuary. We found that larger tides produced the strongest cross-channel currents with a two-layer pattern, compared to weaker currents with three layers during smaller tides. Higher or lower river flow also affected current strength. Comparing two locations, we saw cross-channel currents moving in opposite directions because of differences in the curvature of the river channel. Our results show how channel curvature and Earth’s rotation combine to produce cross-channel currents.

Modeling the population dynamics and movement of Zebra mussels

Zebra mussels have caused significant damage in many lakes and rivers. By using a hybrid population model with discrete-time equations and ordinary differential equations, we represent the zebra mussel's life cycle, growth, and population movement. The dynamics of the larvae (unsettled and settled larvae) are represented during the summer months in a system of two ordinary differential equations, while the juvenile, small adult, and large adult stages are represented by a discrete model with yearly time steps. The goal is to investigate the effects of zebra mussel movement between three different spatial locations and possible control measures. Zebra mussel data and temperature values from three locations in the Hudson River over several years were used to estimate model parameters. We investigate the stability and net reproductive number for our model. We illustrate numerically the hybrid population model for several scenarios of movement and cleaning boats to remove mussels.

Integrating genetic and demographic data to refine indices of abundance for Atlantic sturgeon in the Hudson River, New York

Critical to Atlantic sturgeon Acipenser oxyrinchus oxyrinchus recovery and monitoring is the ability to estimate abundance and identify age- and stock-specific threats to survival. As adult Atlantic sturgeon spend much of their lives broadly distributed in marine and estuarine environments, it is challenging to collect data needed to estimate these demographic parameters in the adult population. Alternatively, data collected from juveniles and subadults before emigration may be used to calculate indices of abundance and provide insights into recruitment dynamics and stage-specific survival. However, uncertainty about stock mixture during early life stages may limit the use of juvenile and subadult data for monitoring recovery. To better understand early life stage stock composition, we conducted a genetic mixed-stock analysis of over 500 juvenile and subadult Atlantic sturgeon captured in an overwintering area in the Hudson River, New York, USA, from 2017 to 2022. The majority of Atlantic sturgeon in our study were natal to the Hudson River population, regardless of sex, size, or age. As such, indices of relative abundance estimated from survey data are expected to primarily characterize the demographic trends of Hudson River juvenile and subadult Atlantic sturgeon. We also found a small proportion of individuals that were most likely to have originated from more distantly located rivers, highlighting the potential for long-distance migration in juvenile and subadult Atlantic sturgeon. Results of this study strengthen our understanding of juvenile and subadult Atlantic sturgeon habitat use in the Hudson River and improve our ability to use data from early age classes to monitor recovery and stage-specific survival.

Spatiotemporal dynamics of spawning habitat distribution of American shad (Alosa sapidissima) in the Hudson River Estuary under multi stressors

Diadromous fishes, known for their extensive migrations between freshwater and marine ecosystems, are highly vulnerable to environmental fluctuations and human activities, making them prone to population declines. Despite awareness of climate change impacts and habitat limitations, the remaining spawning habitat’s biogeography is understudied. The present study focuses on the Hudson River Estuary (HRE) American shad ( Alosa sapidissima) population which is experiencing historically low stock levels, as a case study to investigate the spatiotemporal distribution of its existing spawning habitat. Generalized additive models were used to investigate the effect of some environmental (e.g., temperature, river bottom type) and sampling variables (e.g., sampling location and time) on the spatial distribution of the American shad. Our results provide compelling evidence of an optimal spawning habitat for the American shad, suggesting that environmental factors may not be the primary drivers shaping the distribution of their spawning grounds. The significant relationships between the distribution of spawning habitat and spawning stock biomass indicates that factors beyond the HRE are likely to play the most significant roles in the shad population.

An Eulerian perspective on habitat models of striped bass occurrence in an offshore wind development area

Abstract Offshore wind energy development, including along the US Atlantic coast, frequently occurs within important multispecies migration corridors; however, assessing the regional factors influencing the local Eulerian occurrence of these species poses a significant challenge. We used generalized models incorporating lagged variables and hierarchical formulations to account for temporal dependencies and hierarchical structure that occur outside the narrower frame of a sampled project area. Acoustically tagged striped bass, the most frequently detected species regionally, were sampled using a gridded acoustic telemetry array in the Maryland Wind Energy Area of the US Mid-Atlantic Bight. The daily occurrence of striped bass was better explained by broad-scale sea surface temperature warming patterns than by local concurrent environmental conditions, demonstrating the importance of drivers that occur across the wider spatial scales of migration. Weekly residency patterns were similar between tagging origin groups, suggesting that Chesapeake Bay, Hudson River, Delaware Bay, and other Northwest Atlantic populations migrate synchronously through the Southern Mid-Atlantic Bight and are similarly influenced by sea surface temperature. Our study demonstrates that adapting an Eulerian approach to include lagged variables can improve regional assessments of fish on the move until richer Lagrangian insights become possible through future coordination of telemetry arrays throughout the Mid-Atlantic flyway.

Untangling the Mystery of Intuitive-Analytic Interactions in Crisis Response Operations: A Dual-Process Perspective

Whilst it is often claimed that experienced crisis responders are likely to adopt the intuitive and analytical thinking styles when solving complex problems in time-pressured crisis situations, scholarly efforts to explicate the nature of interactions between the intuitive and analytical modes remain sparse. To bridge this gap, we review four duality-based cognitive models and draw evidence from the Hudson River case study to better understand the patterns of the interplay between the intuitive and analytical information processing modes in time-pressured crisis situations. We found support for the dual-process theory, and note that although intuition is frequently deployed as the default cognitive mode in crisis situations, experienced crisis responders can exploit some features of the analytical mode to validate their intuitive tendencies when required. Based on evidence from the Hudson River case study, a range of intuitive-analytic tension points that largely explain the nature of interactions within the duality framework are identified. The paper concludes by discussing the implications of the dual-process information modes for crisis decision-making.