Scholars@Duke
James Hench

James Hench

Associate Professor of Oceanography
Marine Science and Conservation
jim.hench@duke.edu
135 Duke Marine Lab Rd, Beaufort, NC 28516

Selected Publications

Post-disturbance recovery dynamics of connected coral subpopulations

Journal Article Theoretical Ecology · December 1, 2025 Coral reefs are patchy and connected ecosystems that experience heterogenous environmental conditions, disturbances, and coral population recovery patterns. Connectivity and population growth rates between reef patches can vary at local to subregional (1–1 ... Full text Cite

Curvature Dynamics of a Coastal Barotropic Outflow Jet on a Slope

Journal Article Journal of Physical Oceanography · September 1, 2024 This study adopts a curvature dynamics approach to understand and predict the trajectory of an idealized depth-averaged barotropic outflow onto a slope in shallow water. A novel equation for streamwise curvature dynamics was derived from the barotropic vor ... Full text Cite

Corals survive severe bleaching event in refuges related to taxa, colony size, and water depth.

Journal Article Scientific reports · April 2024 Marine heatwaves are increasing in frequency and duration, threatening tropical reef ecosystems through intensified coral bleaching events. We examined a strikingly variable spatial pattern of bleaching in Moorea, French Polynesia following a heatwave that ... Full text Cite

Coral restoration for coastal resilience: Integrating ecology, hydrodynamics, and engineering at multiple scales

Journal Article Ecosphere · May 1, 2023 The loss of functional and accreting coral reefs reduces coastal protection and resilience for tropical coastlines. Coral restoration has potential for recovering healthy reefs that can mitigate risks from coastal hazards and increase sustainability. Howev ... Full text Cite

Boundary layer dynamics and bottom friction in combined wave-current flows over large roughness elements

Journal Article Journal of Fluid Mechanics · January 25, 2022 In the coastal ocean, interactions of waves and currents with large roughness elements, similar in size to wave orbital excursions, generate drag and dissipate energy. These boundary layer dynamics differ significantly from well-studied small-scale roughne ... Full text Cite

Increasing comparability among coral bleaching experiments.

Journal Article Ecological applications : a publication of the Ecological Society of America · June 2021 Coral bleaching is the single largest global threat to coral reefs worldwide. Integrating the diverse body of work on coral bleaching is critical to understanding and combating this global problem. Yet investigating the drivers, patterns, and processes of ... Full text Cite

Estimating Geometric Properties of Coral Reef Topography Using Obstacle- and Surface-Based Approaches

Journal Article Journal of Geophysical Research: Oceans · June 1, 2020 In shallow water systems like coral reefs, bottom friction is an important term in the momentum balance. Parameterizations of bottom friction require a representation of canopy geometry, which can be conceptualized as an array of discrete obstacles or a co ... Full text Cite

An Island Mass Effect Resolved Near Mo’orea, French Polynesia

Journal Article Frontiers in Marine Science · January 30, 2020 We sought to resolve the extent, variability, and magnitude of productivity enrichment around a high tropical island consistent with the phenomenon of an Island Mass Effect (IME). Key biogeochemical constituents and physical oceanographic parameters were m ... Full text Cite

Collapsing Complexity: Quantifying Multiscale Properties of Reef Topography

Journal Article Journal of Geophysical Research: Oceans · January 1, 2019 Seafloor topography affects a wide range of physical and biological processes; therefore, collapsing the three-dimensional structure of the bottom to roughness metrics is a common challenge in studies of marine systems. Here we assessed the properties capt ... Full text Cite

Understanding differential patterns in coral reef recovery: chronic hydrodynamic disturbance as a limiting mechanism for coral colonization

Journal Article Marine Ecology Progress Series · October 26, 2018 Coral reefs are subject to numerous physical disturbances, and post-disturbance coral recovery potential depends on subsequent re-colonization of impacted habitat. We examined divergent recovery trajectories at 2 proximal reefs disturbed by ship groundings ... Full text Cite

Very high resolution mapping of coral reef state using airborne bathymetric lidar surface-intensity and drone imagery

Journal Article International Journal of Remote Sensing · September 2, 2018 Very high resolution (VHR) airborne data enable detection and physicalmeasurements of individual coral reef colonies. The bathymetric LiDAR system, as an active remote sensing technique, accurately computes the coral reef ecosystem’s surface and reflectanc ... Full text Cite

Critical information gaps impeding understanding of the role of larval connectivity among coral reef islands in an era of Global Change

Journal Article Frontiers in Marine Science · August 27, 2018 Populations of marine organisms on coral reef islands (CRI) are connected in space and time by seawater that transports propagules of plants, animals, and algae. Yet, despite this reality, it is often assumed that routine replenishment of populations of ma ... Full text Cite

Author Correction: High frequency temperature variability reduces the risk of coral bleaching.

Journal Article Nature communications · June 2018 The original version of the Article was missing an acknowledgement of a funding source. The authors acknowledge that A. Safaie and K.Davis were supported by National Science Foundation Award No. 1436254 and G. Pawlak was supported by Award No. 1436522. Thi ... Full text Cite

High resolution topobathymetry using a Pleiades-1 triplet: Moorea Island in 3D

Journal Article Remote Sensing of Environment · April 1, 2018 Worldwide the coastal land-sea interface is increasingly subject to natural and anthropogenic hazards. Monitoring this crucial interface may be addressed with satellite imagery as a cost-efficient mapping solution. Topography and bathymetry, defining the s ... Full text Cite

High frequency temperature variability reduces the risk of coral bleaching.

Journal Article Nature communications · April 2018 Coral bleaching is the detrimental expulsion of algal symbionts from their cnidarian hosts, and predominantly occurs when corals are exposed to thermal stress. The incidence and severity of bleaching is often spatially heterogeneous within reef-scales (<1  ... Full text Cite

Interaction of Waves with Idealized High-Relief Bottom Roughness

Journal Article Journal of Geophysical Research: Oceans · April 1, 2018 Considerable uncertainty exists about how to represent wave bottom friction in coastal systems like reefs where orbital excursions are similar to roughness element size. Here, interactions between waves and large bottom roughness were investigated using La ... Full text Cite

One-dimensional particle tracking with streamline preserving junctions for flows in channel networks

Journal Article Journal of Hydraulic Engineering · February 1, 2018 A pseudo-three-dimensional particle tracking model of drifter paths has been developed to study the movement of scalars through a complex network of tidal channels and junctions. To better simulate dispersion caused by bifurcation and merging at junctions, ... Full text Cite

Interactions of waves with idealized high-relief bottom roughness

Conference Proceedings of the Coastal Engineering Conference · January 1, 2018 Cite

Behavior of a wave-driven buoyant surface jet on a coral reef

Journal Article Journal of Geophysical Research: Oceans · May 1, 2017 A wave-driven surface-buoyant jet exiting a coral reef was studied in order to quantify the amount of water reentrained over the reef crest. Both moored observations and Lagrangian drifters were used to study the fate of the buoyant jet. To investigate in ... Full text Cite

Mapping coral reefs using consumer-grade drones and structure from motion photogrammetry techniques

Journal Article Coral Reefs · March 1, 2017 We propose a novel technique to measure the small-scale three-dimensional features of a shallow-water coral reef using a small drone equipped with a consumer-grade camera, a handheld GPS and structure from motion (SfM) algorithms. We used a GoPro HERO4 wit ... Full text Cite

Assessment of Submarine Groundwater Discharge (SGD) as a Source of Dissolved Radium and Nutrients to Moorea (French Polynesia) Coastal Waters

Journal Article Estuaries and Coasts · November 1, 2016 Previous work has documented large fluxes of freshwater and nutrients from submarine groundwater discharge (SGD) into the coastal waters of a few volcanic oceanic islands. However, on the majority of such islands, including Moorea (French Polynesia), SGD h ... Full text Cite

Simulating social-ecological systems: the Island Digital Ecosystem Avatars (IDEA) consortium.

Journal Article GigaScience · January 2016 Systems biology promises to revolutionize medicine, yet human wellbeing is also inherently linked to healthy societies and environments (sustainability). The IDEA Consortium is a systems ecology open science initiative to conduct the basic scientific resea ... Full text Cite

Accuracy assessment of underwater photogrammetric three dimensional modelling for coral reefs

Conference International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences - ISPRS Archives · January 1, 2016 Recent advances in automation of photogrammetric 3D modelling software packages have stimulated interest in reconstructing highly accurate 3D object geometry in unconventional environments such as underwater utilizing simple and low-cost camera systems. Th ... Full text Cite

Hydrodynamics influence coral performance through simultaneous direct and indirect effects

Journal Article Ecology · June 1, 2015 Hydrodynamic conditions can influence the distribution and abundance of aquatic species in many ways, including directly through disturbance and resource delivery, and indirectly by altering environmental cues and species interactions. In coral reef ecosys ... Full text Open Access Cite

Heat balances and thermally driven lagoon-ocean exchangeson a tropical coral reef system (Moorea, French Polynesia)

Journal Article Journal of Geophysical Research: Oceans · February 25, 2015 The role of surface and advective heat fluxes on buoyancy-driven circulation was examined within a tropical coral reef system. Measurements of local meteorological conditions as well as water temperature and velocity were made at six lagoon locations for 2 ... Full text Open Access Cite

Wave transformation and wave-driven flow across a steep coral reef

Journal Article Journal of Physical Oceanography · August 14, 2013 Observations of waves, setup, and wave-driven mean flows were made on a steep coral forereef and its associated lagoonal system on the north shore of Moorea, French Polynesia. Despite the steep and complex geometry of the forereef, and wave amplitudes that ... Full text Open Access Cite

Observations of spatial flow patterns at the coral colony scale on a shallow reef flat

Journal Article Journal of Geophysical Research: Oceans · March 1, 2013 Although small-scale spatial flow variability can affect both larger-scale circulation patterns and biological processes on coral reefs, there are few direct measurements of spatial flow patterns across horizontal scales <100 m. Here flow patterns on a sha ... Full text Open Access Cite

Coupled physical, chemical, and microbiological measurements suggest a connection between internal waves and surf zone water quality in the Southern California Bight

Journal Article Continental Shelf Research · February 15, 2012 Internal waves have been implicated in the cross-shore transport of scalars such as larvae, nutrients, and pollutants at locations around the world. The present study combines physical measurements with a comprehensive set of surf zone water quality measur ... Full text Open Access Cite

The island-scale internal wave climate of Moorea, French Polynesia

Journal Article Journal of Geophysical Research: Oceans · January 1, 2012 Analysis of five-year records of temperatures and currents collected at Moorea reveal strong internal wave activity at predominantly semi-diurnal frequencies impacting reef slopes at depths 30m around the entire island. Temperature changes of 1.5C to 3C ar ... Full text Open Access Cite

A framework for understanding drag parameterizations for coral reefs

Journal Article Journal of Geophysical Research: Oceans · January 1, 2011 In a hydrodynamic sense, a coral reef is a complex array of obstacles that exerts a net drag force on water moving over the reef. This drag is typically parameterized in ocean circulation models using drag coefficients (C D) or roughness length scales (z0) ... Full text Cite

Flow effects on benthic grazing on phytoplankton by a Caribbean reef

Journal Article Limnology and Oceanography · September 1, 2010 We present measurements of flows and fluxes of phytoplankton to Conch Reef, Florida, a Caribbean reef dominated by sponges and soft corals, located in 15 m of water offshore of Key Largo. Vertical profiles of chlorophyll a, a proxy for phytoplankton biomas ... Full text Cite

Analysis of bottom-track and compass error in a self-contained acoustic doppler diver navigation console

Journal Article Journal of Atmospheric and Oceanic Technology · July 1, 2010 The Cobra-Tac (Teledyne RD Instruments) is a self-contained diver navigation system based on acoustic Doppler velocity log (DVL) technology that uses dead reckoning to compute displacements from a known starting point. The navigational accuracy of the syst ... Full text Cite

Lateral circulation in well-mixed and stratified estuarine flows with curvature

Journal Article Journal of Physical Oceanography · July 14, 2009 A field experiment was conducted to examine stratified and unstratified curvature-generated lateral circulation and momentum balances in an estuarine tidal channel. Conductivity, temperature, depth, and current profiler data were collected vertically and l ... Full text Cite

Thermal variability in a tidal river

Journal Article Estuaries and Coasts · January 1, 2009 In this paper, we discuss observations of temperature variability in the tidal portion of the San Joaquin River in California. The San Joaquin River makes up the southern portion of the Sacramento San Joaquin Delta, the eastern end of San Francisco Bay. Ob ... Full text Cite

Reef structure regulates small-scale spatial variation in coral bleaching

Journal Article Marine Ecology Progress Series · October 28, 2008 Coral bleaching is often characterized by high spatial variation across reef systems. Using a field survey and manipulative experiment, we tested whether the physical structure of coral reefs modifies environmental conditions that, in turn, influence spati ... Full text Cite

Effects of western boundary current dynamics on the internal wave field of the Southeast Florida shelf

Journal Article Journal of Geophysical Research: Oceans · September 8, 2008 Shelf sea internal wave fields are typically highly variable and dominated by wind and tidal forces. However this is not necessarily true for outer shelf regions or very narrow shelves where remote physical processes originating over the slope or deep ocea ... Full text Cite

Extracting Reynolds stresses from acoustic Doppler current profiler measurements in wave-dominated environments

Journal Article Journal of Atmospheric and Oceanic Technology · February 1, 2008 Surface waves introduce velocity correlations that bias and often dominate Reynolds stress estimates made using the traditional variance method for acoustic Doppler current profilers (ADCPs). This analysis shows that the wave bias is the sum of a real wave ... Full text Cite

How reef structure regulates small-scale spatial variation in coral bleaching

Journal Article Marine Ecology Progress Series · 2008 Cite

Episodic circulation and exchange in a wave-driven coral reef and lagoon system

Journal Article Limnology and Oceanography · January 1, 2008 We examined the role of wave-driven circulation relative to wind and buoyancy forcing in a coral reef-lagoon system. Circulation measurements in Paopao Bay, Moorea, French Polynesia, during austral summer show the importance of waves in driving flows over ... Full text Cite

Comparison of Reynolds stress estimates derived from standard and fast-ping ADCPs

Journal Article Journal of Atmospheric and Oceanic Technology · June 1, 2006 A field experiment was conducted to directly compare the effects of different sampling modes on Reynolds stress estimates calculated from acoustic Doppler current profilers (ADCPs). Two 1.2-MHz ADCPs were deployed concurrently over a fortnightly cycle: one ... Full text Cite

Spatial patterns in the ovigerous Callinectes sapidus spawning migration: Results from a coupled behavioral-physical model

Journal Article Marine Ecology Progress Series · June 9, 2005 Ovigerous blue crabs Callinectes sapidus use ebb-tide transport (ETT), a vertical migratory behavior in which crabs ascend into the water column during ebb tides, to migrate from estuarine adult habitats to coastal larval release locations. We have develop ... Full text Cite

Movement patterns and trajectories of ovigerous blue crabs Callinectes sapidus during the spawning migration

Journal Article Estuarine, Coastal and Shelf Science · August 1, 2004 Female blue crabs (Callinectes sapidus Rathbun) migrate from low salinity estuarine regions to high salinity regions near the ocean to release larvae. During this migration, ovigerous females use ebb-tide transport, a vertical migratory behavior in which t ... Full text Cite

Testing a selective tidal-stream transport model: Observations of female blue crab (Callinectes sapidus) vertical migration during the spawning season

Journal Article Limnology and Oceanography · January 1, 2004 Female blue crabs, Callinectes sapidus, mate in estuaries and undergo a seaward spawning migration to release larvae. According to the prevailing model, females with mature embryos use nocturnal ebb-tide transport (ETT) to move seaward, release larvae, and ... Full text Cite

Transient tidal circulation and momentum balances at a shallow inlet

Journal Article Journal of Physical Oceanography · 2003 An analysis of transient momentum balances is carried out to elucidate circulation, dynamics, and exchange mechanisms at shallow barotropic tidal inlets. Circulation is computed using a depth-integrated, fully nonlinear, time-stepping, finite-element model ... Full text Cite

Lateral dynamic analysis and classification of barotropic tidal inlets

Journal Article Continental Shelf Research · December 1, 2002 The dynamical balances at shallow tidal inlets are highly nonlinear, and can vary substantially over sub-kilometer scales. In this study, barotropic dynamics are examined with numerical experiments on a series of idealized inlets with differing inlet width ... Full text Cite

Small-scale shear effects on heterocystous cyanobacteria

Journal Article Limnology and Oceanography · January 1, 2002 Planktonic, filamentous, heterocystous cyanobacteria form blooms in certain nitrogen-limited ecosystems but are absent or rare in others that seem to have suitable environmental conditions. We tested the hypothesis that small-scale shear affects physiologi ... Full text Cite

Lateral dynamic analysis and classification of barotropic tidal inlets

Journal Article Continental Shelf Research · 2002 Cite

A portable retractable ADCP boom-mount for small boats

Journal Article Estuaries · January 1, 2000 This paper describes the design, testing, and application of a portable and retractable shipboard acoustic Doppler current profiler (ADCP) boom-mount. The boom is specifically adapted for small fiberglass boats working with a minimal crew. The design permi ... Full text Cite

Tidal inlet circulation: observations, model skill and momentum balances

Journal Article Proceedings of the International Conference on Estuarine and Coastal Modeling · January 1, 2000 A combined observational and modeling study of circulation at Beaufort Inlet, North Carolina is underway to elucidate circulation patterns and momentum balances at shallow barrier island inlets. The observational data include fourteen shipboard ADCP cruise ... Cite

Circulation and larval fish transport within a tidally dominated estuary

Journal Article Fisheries Oceanography · December 1, 1999 In March 1996 two surveys of larval fish abundance and water flow were carried out within the estuarine region near Beaufort Inlet, NC. Each survey extended over two full semidiurnal tidal cycles and included measurements of larvae concentration and veloci ... Full text Cite

Barotropic tidal and wind-driven larval transport in the vicinity of a barrier island inlet

Journal Article Fisheries Oceanography · December 1, 1999 Fish species such as Atlantic menhaden (Brevoortia tyrannus) must often transit relatively small barrier island inlets to move from their continental shelf spawning grounds to estuarine nurseries, where they spend their juvenile phase. Physical transport t ... Full text Cite

Tidal and subtidal fluctuations in temperature, salinity and pressure for the winter 1996 larval ingress experiment - Beaufort Inlet, NC

Journal Article Fisheries Oceanography · December 1, 1999 A multidisciplinary field experiment was conducted to compare water properties, larval abundances, and transport and retention processes at Beaufort Inlet and two channels leading to the estuarine nursery grounds. Temperature, salinity and subsurface press ... Full text Cite

Flood tide circulation near Beaufort Inlet, North Carolina: Implications for larval recruitment

Journal Article Estuaries · January 1, 1999 Drifter tracks and shipboard CTD observations have revealed a number of distinct features of the flood tide circulation carrying water through Beaufort Inlet, North Carolina. One of the most noteworthy of these features is a nearshore jet in the flow carry ... Full text Cite

Tidal circulation and larval transport through a Barrier Island inlet

Journal Article Proceedings of the International Conference on Estuarine and Coastal Modeling · December 1, 1997 As a part of the NOAA South Atlantic Bight Recruitment Experiment (SABRE), a detailed modeling study is in progress to define likely larval transport pathways in the vicinity of Beaufort Inlet, North Carolina. Modeled tidal circulation near the inlet has b ... Cite

Analysis and application of Eulerian finite element methods for the transport equation

Journal Article Proceedings of the International Conference on Estuarine and Coastal Modeling · December 1, 1997 A comparison of various Eulerian finite element schemes for the transport equation is made using Fourier analysis. The relative merits of each scheme are discussed and one scheme is selected for a two-dimensional field application. A series of runs are mad ... Cite