Cédric Marcel Guigand

University of Miami | UM · Rosenstiel School of Marine and Atmospheric Science

Our unmanned aerial system (UAS) current mapping is based on optical video data of the sea surface. We use three-dimensional fast Fourier transform and least-squares fitting to measure the surface waves’ phase velocities and the currents via the linear dispersion relationship. Our UAS is a low-cost off-the-shelf quadcopter with inaccurate camera po...

Our knowledge of zooplankton in proximity to benthic marine habitats is hampered by challenges sampling near complex substrates. To address this, we deployed light traps near the benthos of four depth-specific coral reef ecosystems to measure nocturnal zooplankton abundance and assemblage composition. Replicate light traps at shallow shelf (SS10, <...

Much of the vertical transport near the surface of the ocean, which plays a critical role in the transport of dissolved nutrients and gases, is thought to be associated with ageostrophic submesoscale phenomena. Vertical velocities are challenging not only to model accurately, but also to measure because of how difficult they are to locate in the su...

This study evaluates shipboard marine X‐band radar (MR) near‐surface current and bathymetry measurements under shallow water conditions. The retrieval algorithm is based on the surface wave signal within three‐dimensional wave number frequency MR backscatter intensity variance spectra. The MR data were collected during a research cruise that invest...

The dynamics of crude oil and different surface ocean drifters were compared to study the physical processes that govern the transport and landfall of marine oil spills. In a wave-tank experiment, drifters with drogue did not follow oil slicks. However, patches of undrogued drifters and thin bamboo plates did spread at the same rate and in the same...

For all fishes, hatching is a short but crucial event, and the conditions under which it occurs considerably influence the success of the larvae. For coral reef fish, hatching is even more important because it marks the beginning of the dispersal phase. The timing of hatching dictates the conditions that the larvae will encounter, potentially influ...

Oil slicks and sheens reside at the air-sea interface, a region of the ocean that is notoriously difficult to measure. Little is known about the velocity field at the sea surface in general, making predictions of oil dispersal difficult. The Ship-Tethered Aerostat Remote Sensing System (STARSS) was developed to measure Lagrangian velocities at the...

Advances in drifter technology applied to oil spill studies from 1970 to the present are summarized here. Initially, drifters designed for oil spill response were intended to remotely track trajectories of accidental spills and help guide responders. Most recently, inexpensive biodegradable drifters were developed for massive deployments, making it...

Formed in the aftermath of the Deepwater Horizon event, the largest accidental marine oil spill, the Consortiumfor Advanced Research on Transport of Hydrocarbons in the Environment (CARTHE) focused on understanding the physical processes controlling the transport of material from a deep blowout all the way to the coast. Even though CARTHE was initi...

The rise of in situ plankton imaging systems, particularly high‐volume imagers such as the In Situ Ichthyoplankton Imaging System, has increased the need for fast processing and accurate classification tools that can identify a high diversity of organisms and nonliving particles of biological origin. Previous methods for automated classification ha...

The Taylor Energy Site is located in the vicinity of the Mississippi Delta region over the Northern Gulf of Mexico (NGoM). Surface oil patches have been persistently observed within this site since 2004, when an oil rig was destroyed by Hurricane Ivan. A multiplatform observational experiment was conducted in April 2017 to investigate, for the firs...

The Lagrangian Submesoscale Experiment (LASER) involved the deployment of ~1000 biodegradable GPS-tracked Consortium for Advanced Research on Transport of Hydrocarbon in the Environment (CARTHE) drifters to measure submesoscale upper-ocean currents and their potential impact on oil spills. The experiment was conducted from January to February 2016...

The Lagrangian Submesoscale Experiment (LASER) was designed to study surface flows during winter conditions in the northern Gulf of Mexico. More than 1000 mostly biodegradable drifters were launched. The drifters consisted of a surface floater extending 5 cm below the surface, containing the satellite tracking system, and a drogue extending 60 cm b...

Floating oil, plastics, and marine organisms are continually redistributed by ocean surface currents. Prediction of their resulting distribution on the surface is a fundamental, long-standing, and practically important problem. The dominant paradigm is dispersion within the dynamical context of a nondivergent flow: objects initially close together...

Plastics and spilled oil pose a critical threat to marine life and human health. As a result of wind forcing and wave motions, theoretical and laboratory studies predict very strong velocity variation with depth over the upper few centimeters of the water column, an observational blind spot in the real ocean. Here we present the first-ever ocean me...

Targeted observations of submesoscale currents are necessary to improve our understanding of oceanic mixing, but these dynamics occur at spatiotemporal scales that are currently challenging to detect. Prior studies have recently shown that submesoscale surface velocity field can be measured by tracking hundreds of surface drifters released in tight...

Big data " are becoming common in biological oceanography with the advent of sampling technologies that can generate multiple, high-frequency data streams. Given the need for " big " data in ocean health assessments and ecosystem management, identifying and implementing robust, and efficient processing approaches is a challenge for marine scientist...

Marine teleost fishes often experience over 99% mortality in the early life stages (eggs and larvae), yet larval survival is essential to population sustainability. Marine fish larvae from a wide range of families display elaborate, delicate features that bear little resemblance to adult forms and hinder their swimming escape ability by increasing...

Plankton patch dynamics strongly influences rates of trophic transfer and many ecological processes, yet patchiness is poorly described, especially on fine-scales (cm to 10s of m). We deployed the In Situ Ichthyoplankton Imaging System beneath the Mississippi River plume to measure horizontal distributions of zooplankton across three depth zones (1...

Imaging systems were developed to explore the fine scale distributions of plankton (<10 m), but they generate huge datasets that are still a challenge to handle rapidly and accurately. So far, imaged organisms have been either classified manually or pre-classified by a computer program and later verified by human operators. In this paper, we post-p...

Current knowledge of zooplankton distribution at very fine scale (~1 m) is limited, as even the most advanced nets integrate over 10s of m of depth and 100s of m horizontally. Yet, this fine scale is the one relevant for biological interactions such as predation or gregarious behaviour. New imaging tools, like the In Situ Ichthyoplankton Imaging Sy...

Ocean fronts represent productive regions of the ocean, but predator-prey interactions within these features are poorly understood partially due to the coarse-scale and biases of net-based sampling methods. We used the In Situ Ichthyoplankton Imaging System (ISIIS) to sample across a front near the Georges Bank shelf edge on two separate sampling d...

Mesoscale fronts occur frequently in many coastal areas and often are sites of elevated productivity; however, knowledge of the fine-scale distribution of zooplankton at these fronts is lacking, particularly within the mid-trophic levels. Furthermore, small (<13 cm) gelatinous zooplankton are ubiquitous, but are under-studied, and their abundances...

Current knowledge of larval fish distribution in the fine-scale (<10m) is limited, as even the most advanced nets integrate over 10s of m of depth and 100s of m horizontally. Yet, this fine-scale is the one relevant for biological interactions such as predation or gregarious behaviour. New imaging tools, like the In Situ Ichthyoplankton Imaging Sys...

The behavior of reef fish larvae, equipped with a complex toolbox of sensory apparatus, has become a central issue in understanding their transport in the ocean. In this study pelagic reef fish larvae were monitored using an unmanned open-ocean tracking device, the drifting in-situ chamber (DISC), deployed sequentially in oceanic waters and in reef...

Statistical Analyses. (DOC)

Movement analysis of individual fish larvae deployed in the Drifting In Situ Chamber (DISC) at One Tree Island (OTI) on the Great Barrier Reef, February of 2009. A) cardinalfish larva of the species Cheilodipterus quinquelineatus (Family: Apogonidae) in plume water (deployment #55); B) cardinalfish larva C. quinquelineatus in ocean water (deploymen...

Thin layers of phytoplankton are well documented, common features in coastal areas globally, but little is known about the relationships of these layers to higher trophic levels. We deployed the In Situ Ichthyoplankton Imaging System (ISIIS) to simultaneously quantify the three trophic levels of plankton, including phytoplankton, primary consumers...

Poster presented at the SEEDs interdisciplinary workshop

Plankton and larval fish sampling programs often are limited by a balance between sampling frequency (for precision) and costs. Advancements in sampling techniques hold the potential to add considerable efficiency and, therefore, add sampling frequency to improve precision. We compare a newly developed plankton imaging system, In Situ Ichthyoplankt...

1] We sampled a front detected by SST gradient, ocean color imagery, and a Spray glider south of San Nicolas Island in the Southern California Bight between 14 and 18 October 2010. We sampled the front with an unusually extensive array of instrumentation, including the Continuous Underway Fish Egg Sampler (CUFES), the undulating In Situ Ichthyoplan...

Among eukaryotes, four major phytoplankton lineages are responsible for marine photosynthesis; prymnesiophytes, alveolates, stramenopiles, and prasinophytes. Contributions by individual taxa, however, are not well known, and genomes have been analyzed from only the latter two lineages. Tiny "picoplanktonic" members of the prymnesiophyte lineage hav...

Critical gaps in our understanding of the distributions, interactions, life histories and preferred habitats of large and medium-size pelagic fishes severely constrain the implementation of ecosystem-based, spatially structured fisheries management approaches. In particular, spawning distributions and the environmental characteristics associated wi...

Vertical distribution patterns were studied in the community of coral-reef fish larvae around Tetiaroa (French Polynesia) using vertically stratified net tows within the first 100~m of the water column. These patterns were examined statistically using an approach based on the center of mass of larval patches. Regression trees first highlighted larg...

The pelagic larval phase represents a major opportunity for dispersal in benthic organisms, yet behaviors controlling and potentially limiting dispersal are still largely unknown for most larvae. Here, we present a new means of observing the orientation of larvae of all developmental stages in the pelagic environment. A cylindrical frame holding a...

Researchers at the University of Miami have developed a fully automated high-throughput specimen recognition software to assist the plankton imaging system, the In-Situ Ichthyoplankton Imaging System (ISIIS). The software uses novel machine vision and learning methods to achieve the best possible robustness to a high amount of data intricacies such...

Over the last two decades, there has been an accelerating advancement of acoustic and optical plankton samplers, opening many opportunities for fine-scale studies of plankton distribution. To date, however, the imaging systems have been limited in the volume of water being sampled, thereby restricting their utility to quantifying highly abundant, s...

A central question in marine ecology today is to understand the spatial scales over which populations are connected by larval dispersal. Although coral reef fish larvae develop strong behavioral capabilities during the processes of dispersal (e.g., vertical migration, swimming), the influence of these capabilities on survival depends on the ability...

We have built a high resolution towed digital imaging system (ISIIS) capable of imaging water volumes sufficient to accurately quantify even rare plankton (e.g. larval fish) in situ. This imaging system produces very high resolution imagery at very high data rates necessitating automated image analysis. As we are interested in the identification an...

While there is mounting evidence that larval coral reef fishes develop strong behavioral capabilities through ontogeny (e.g. swimming) and at settlement (e.g. orientation to sound), the influence of these capabilities on dispersal patterns depends on their ability to orient in the open ocean. A new apparatus was designed to detect, quantify, and un...

Recruitment levels of fishes are potentially related to the abundance of larval fishes and their food source. A system that could allow for the concurrent investigation of fine-scale distribution of fish larvae and their potential prey could add significantly to the understanding of the early life history of marine fishes. A coupled Multiple Openin...

1. ABSTRACT One driving factor improving the resolution of oceanographic sampling has been the observation of fine structure in the ocean. As oceanographers improve their sample resolution, the finer patterns that are discovered lead to a better understanding (and new questions) about dynamic processes in the ocean. To date, current technologies av...