Life Sciences Commons^™

Performance Evaluation Of Cetacean Species Distribution Models Developed Using Generalized Additive Models And Boosted Regression Trees, Elizabeth A. Becker, James V. Carretta, Karin A. Forney, Jay Barlow, Stephanie Brodie, Ryan Hoopes, Michael G. Jacox, Sara M. Maxwell, Jessica V. Redfern, Nicholas B. Sisson, Heather Welch, Elliott L. Hazen

Biological Sciences Faculty Publications

Species distribution models (SDMs) are important management tools for highly mobile marine species because they provide spatially and temporally explicit information on animal distribution. Two prevalent modeling frameworks used to develop SDMs for marine species are generalized additive models (GAMs) and boosted regression trees (BRTs), but comparative studies have rarely been conducted; most rely on presence-only data; and few have explored how features such as species distribution characteristics affect model performance. Since the majority of marine species BRTs have been used to predict habitat suitability, we first compared BRTs to GAMs that used presence/absence as the response variable. We then …

Using Genetics To Inform Restoration And Predict Resilience In Declining Populations Of A Keystone Marine Sponge, Sarah M. Griffiths, Evelyn D. Taylor-Cox, Donald C. Behringer, Mark J. Butler Iv, Richard F. Preziosi

Biological Sciences Faculty Publications

Genetic tools can have a key role in informing conservation management of declining populations. Genetic diversity is an important determinant of population fitness and resilience, and can require careful management to ensure sufficient variation is present. In addition, population genetics data reveal patterns of connectivity and gene flow between locations, enabling mangers to predict recovery and resilience, identify areas of local adaptation, and generate restoration plans. Here, we demonstrate a conservation genetics approach to inform restoration and management of the loggerhead sponge (Spheciospongia vesparium) in the Florida Keys, USA. This species is a dominant, habitat-forming component of marine ecosystems in …

Translating Globally Threatened Marine Species Information Into Regional Guidance For The Gulf Of Mexico, Kyle Strongin, Beth Polidoro, Christi Linardich, Gina Ralph, Kent Carpenter

Biological Sciences Faculty Publications

A comprehensive understanding of the status of marine organisms in the Gulf of Mexico is critical to the conservation and improved management of marine biodiversity in the region. Threats and extinction risk, based on application of the IUCN Red List Categories and Criteria at the global level, were analyzed for 1,300 Gulf of Mexico marine species. These species include all known marine mammals, sea birds, marine reptiles, cartilaginous fishes, bony shorefishes, corals, mangroves, seagrasses and complete clades of select invertebrates. Analyses showed that 6% of these species are threatened, 2% Near Threatened, 9% Data Deficient, and 83% Least Concern. However, …

Conserving Spawning Stocks Through Harvest Slot Limits And No-Take Protected Areas, Gaya Gnanalingam, Holly Gaff, Mark J. Butler Iv

Biological Sciences Faculty Publications

The key to the conservation of harvested species is the maintenance of reproductive success. Yet for many marine species large, old individuals are targeted despite their disproportionate contribution to reproduction. We hypothesized that a combination of no-take marine protected areas (MPAs) and harvest slot limits (maximum and minimum size limits) would result in the conservation of large spawning individuals under heavy harvest. We tested this approach under different harvest intensities with a 2-sex, stage-structured metapopulation model for the Caribbean spiny lobster (Panulirus argus). P. argus is intensively harvested in the Caribbean, and in many localities large, mature individuals no longer …

Standardized Short-Term Acute Heat Stress Assays Resolve Historical Differences In Coral Thermotolerance Across Microhabitat Reef Sites, Christian R. Voolstra, Carol Buitrago-López, Gabriela Perna, Anny Cárdenas, Benjamin C. C. Hume, Nils Rädecker, Daniel J. Barshis

Biological Sciences Faculty Publications

Coral bleaching is one of the main drivers of reef degradation. Most corals bleach and suffer mortality at just 1–2°C above their maximum monthly mean temperatures, but some species and genotypes resist or recover better than others. Here, we conducted a series of 18‐hr short‐term acute heat stress assays side‐by‐side with a 21‐day long‐term heat stress experiment to assess the ability of both approaches to resolve coral thermotolerance differences reflective of in situ reef temperature thresholds. Using a suite of physiological parameters (photosynthetic efficiency, coral whitening, chlorophyll a , host protein, algal symbiont counts, and algal type association), we assessed …

Correction: New Approaches For Assessing Squid Fin Motions: Coupling Proper Orthogonal Decomposition With Volumetric Particle Tracking Velocimetry (Doi:10.1242/Jeb.176750), Ian K. Bartol, Paul S. Krueger, Carly A. York, Joseph T. Thompson

Biological Sciences Faculty Publications

Squid, which swim using a coupled fin/jet system powered by muscular hydrostats, pose unique challenges for the study of locomotion. The high flexibility of the fins and complex flow fields generated by distinct propulsion systems require innovative techniques for locomotive assessment. For this study, we used proper orthogonal decomposition (POD) to decouple components of the fin motions and defocusing digital particle tracking velocimetry (DDPTV) to quantify the resultant 3D flow fields. Kinematic footage and DDPTV data were collected from brief squid, Lolliguncula brevis [3.1–6.5 cm dorsal mantle length (DML)], swimming freely in a water tunnel at speeds of 0.39–7.20 DML …

Predator Water Balance Alters Intraguild Predation In A Streamsidefood Web, Israel L. Leinbach, Kevin E. Mccluney, John L. Sabo

Biological Sciences Faculty Publications

Previous work suggests that animal water balance can influence trophic interactions, with predators increasing their consumption of water-laden prey to meet water demands.But it is unclear how the need for water interacts with the need for energy to drive trophic interactions under shifting conditions. Using manipulative field experiments, we show that water balance influences the effects of top predators on prey with contrasting ratios of water and energy, altering the frequency of intraguild predation. Water-stressed top predators (large spiders) negatively affect water-laden basal prey (crickets), especially male prey with higher water content, whereas alleviation of water limitation causes top predators …

Editorial: Advances In The Biology And Conservation Of Marine Turtles, Sara M. Maxwell, Annette C. Broderick, Peter H. Dutton, Sabrina Fossette-Halot, Mariana M.P.B. Fuentes, Richard D. Reina

Biological Sciences Faculty Publications

(First Paragraph) Marine turtles have been the subject of research over many decades, inspired by their unique life history and necessitated by their declining populations from a suite of human impacts including direct harvest, bycatch in marine fisheries, pollution, and climate change. Despite this, much about marine turtle biology has remained a mystery (Godley et al., 2008; Rees et al., 2016; Wildermann et al., 2018), but the rate of scientific discovery is increasing rapidly. As research techniques and conservation practices expand, the marine turtle research community has kept abreast of these developments and their application to marine turtles. In this …

Mapping Status And Conservation Of Global At-Risk Marine Biodiversity, Casey C. O'Hara, Juan Carlos Villaseñor-Derbez, Gina M. Ralph, Benjamin S. Halpern

Biological Sciences Faculty Publications

To conserve marine biodiversity, we must first understand the spatial distribution and status of at‐risk biodiversity. We combined range maps and conservation status for 5,291 marine species to map the global distribution of extinction risk of marine biodiversity. We find that for 83% of the ocean, >25% of assessed species are considered threatened, and 15% of the ocean shows >50% of assessed species threatened when weighting for range‐limited species. By comparing mean extinction risk of marine biodiversity to no‐take marine reserve placement, we identify regions where reserves preferentially afford proactive protection (i.e., preserving low‐risk areas) or reactive protection (i.e., mitigating …

Parasitic Dinoflagellate Hematodinium Perezi Prevalence In Larval And Juvenile Blue Crabs Callinectes Sapidus From Coastal Bays Of Virginia, H. J. Small, J. P. Huchin-Mian, K. S. Reece, K. M. Pagenkopp Lohan, Mark J. Butler Iv, J. D. Shields

Biological Sciences Faculty Publications

The parasitic dinoflagellate Hematodinium perezi infects the American blue crab Callinectes sapidus and other decapods along the Eastern seaboard and Gulf of Mexico coast of the USA. Large juvenile and adult blue crabs experience high mortality during seasonal outbreaks of H. perezi, but less is known about its presence in the early life history stages of this host. We determined the prevalence of H. perezi in megalopae and early benthic juvenile crabs from multiple locations along the Virginia portion of the Delmarva Peninsula. The DNA of H. perezi was not detected in any megalopae collected from several locations within …

Seasonal Spatial Segregation In Blue Sharks (Prionace Glauca) By Sex And Size Class In The Northeast Pacific Ocean, Sara M. Maxwell, Kylie L. Scales, Steven Bograd, Dana K. Briscoe, Heidi Dewar, Elliott L. Hazen, Rebecca L. Lewison, Heather Welch, Larry B. Crowder

Biological Sciences Faculty Publications

Aim: Animal tracking can provide unique insights into the ecology and conservation of marine species, such as the partitioning of habitat, including differences between life history stages or sexes, and can inform fisheries stock assessments, bycatch reduction and spatial management such as dynamic management.

Location: Northeast Pacific Ocean.

Methods: We used satellite tracking data from 47 blue sharks (Prionace glauca) from the Northeast Pacific to determine movements and home range along the west coast of North America, and sex–size class (immature females, mature males) specific habitat preferences using boosted regression trees. Using a suite of static and dynamic …

Adaptive Signatures In Thermal Performance Of The Temperate Coral Astrangia Poculata, H. E. Aichelman, Richard C. Zimmerman, Daniel J. Barshis

Biological Sciences Faculty Publications

Variation in environmental characteristics and divergent selection pressures can drive adaptive differentiation across a species' range. Astrangia poculata is a temperate scleractinian coral that provides unique opportunities to understand the roles of phenotypic plasticity and evolutionary adaptation in coral physiological tolerance limits. A. poculata inhabits hard bottom ecosystems from the northwestern Atlantic to the Gulf of Mexico and withstands an annual temperature range up to 20° C. Additionally, A. poculata is facultatively symbiotic and co-occurs in both symbiotic ("brown") and aposymbiotic ("white") states. Here, brown and white A. poculata were collected from Virginia (VA) and Rhode Island (RI), USA and …

Sponges Structure Water-Column Characteristics In Shallow Tropical Coastal Ecosystems, Marla M. Valentine, Mark J. Butler Iv

Biological Sciences Faculty Publications

Sponges can have powerful effects on ecosystem processes in shallow tropical marine ecosystems. They drive benthic-pelagic coupling by filtering dissolved and particulate organic matter from the water column, alter water chemistry in association with their symbiotic microorganisms, and increase habitat structural complexity. Anthropogenic degradation of coastal waters is widespread and can reduce the density and diversity of foundation species such as sponges, potentially diminishing their contributions to ecosystem processes. We used a novel mesocosm design that minimized artifacts associated with traditional single-species and closed-system filtration experiments to examine the effects of water turnover and sponge biomass on water-column properties. Using …

High-Frequency Temperature Variability Mirrors Fixed Differences In Thermal Limits Of The Massive Coral Porites Lobata, Daniel J. Barshis, Charles Birkeland, Robert J. Toonen, Ruth D. Gates, Jonathon H. Stillman

Biological Sciences Faculty Publications

Spatial heterogeneity in environmental characteristics can drive adaptive differentiation when contrasting environments exert divergent selection pressures. This environmental and genetic heterogeneity can substantially influence population and community resilience to disturbance events. Here, we investigated corals from the highly variable back-reef habitats of Ofu Island in American Samoa that thrive in thermal conditions known to elicit widespread bleaching and mortality elsewhere. To investigate the relative importance of acclimation versus site of origin in shaping previously observed differences in coral tolerance limits at Ofu Island, specimens of the common Indo-Pacific coral Porites lobata from locations with differing levels of thermal variability were …

Troubled Waters: Threats And Extinction Risk Of The Sharks, Rays And Chimaeras Of The Arabian Sea And Adjacent Waters, Rima W. Jabado, Peter M. Kyne, Riley A. Pollom, David A. Ebert, Colin A. Simpfendorfer, Gina M. Ralph, Shakha S. Al Dhaheri, K. V. Akhilesh, Khadeeja Ali, Mohamud Hassan Ali

Biological Sciences Faculty Publications

The extinction risk of sharks, rays and chimaeras is higher than that for most other vertebrates due to low intrinsic population growth rates of many species and the fishing intensity they face. The Arabian Sea and adjacent waters border some of the most important chondrichthyan fishing and trading nations globally, yet there has been no previous attempt to assess the conservation status of species occurring here. Using IUCN Red List of Threatened Species Categories and Criteria and their guidelines for application at the regional level, we present the first assessment of extinction risk for 153 species of sharks, rays and …

Dermal Mycobacteriosis And Warming Sea Surface Temperatures Are Associated With Elevated Mortality Of Striped Bass In Chesapeake Bay, Maya L. Groner, John M. Hoenig, Roger Pradel, Rémi Choquet, Wolfgang K. Vogelbein, David T. Gauthier, Marjorie A. M. Friedrichs

Biological Sciences Faculty Publications

Temperature is hypothesized to alter disease dynamics, particularly when species are living at or near their thermal limits. When disease occurs in marine systems, this can go undetected, particularly if the disease is chronic and progresses slowly. As a result, population-level impacts of diseases can be grossly underestimated. Complex migratory patterns, stochasticity in recruitment, and data and knowledge gaps can hinder collection and analysis of data on marine diseases. New tools enabling quantification of disease impacts in marine environments include coupled biogeochemical hydrodynamic models (to hindcast key environmental data), and multievent, multistate mark-recapture (MMSMR) (to quantify the effects of environmental …

Genetic Patterns In Peripheral Marine Populations Of The Fusilier Fish Caesio Cuning Within The Kuroshio Current, Amanda S. Ackiss, Christopher E. Bird, Yuichi Akita, Mudjekeewis D. Santos, Katsunori Tachihara, Kent E. Carpenter

Biological Sciences Faculty Publications

Aim: Mayr’s central‐peripheral population model (CCPM) describes the marked differences between central and peripheral populations in genetic diversity, gene flow, and census size. When isolation leads to genetic divergence, these peripheral populations have high evolutionary value and can influence biogeographic patterns. In tropical marine species with pelagic larvae, powerful western‐boundary currents have great potential to shape the genetic characteristics of peripheral populations at latitudinal extremes. We tested for the genetic patterns expected by the CCPM in peripheral populations that are located within the Kuroshio Current for the Indo‐Pacific reef fish, Caesio cuning.

Methods: We used a panel of 2,677 …

Global Conservation Status Of Marine Pufferfishes (Tetraodontiformes: Tetraodontidae), Emilie Stump, Gina M. Ralph, Mia T. Comeros-Raynal, Keiichi Matsuura, Kent E. Carpenter

Biological Sciences Faculty Publications

Puffers are biologically and ecologically fascinating fishes best known for their unique morphology and arsenal of defenses including inflation and bioaccumulation of deadly neurotoxins. These fishes are also commercially, culturally, and ecologically important in many regions. One-hundred-and-fifty-one species of marine puffers were assessed against the International Union for Conservation of Nature (IUCN) Red List Criteria at a 2011 workshop held in Xiamen, China. Here we present the first comprehensive review of puffer geographic and depth distribution, use and trade, and habitats and ecology and a summary of the global conservation status of marine puffers, determined by applying the International Union …

Sea Turtles And Survivability In Demersal Trawl Fisheries: Do Comatose Olive Ridley Sea Turtles Survive Post-Release?, Sara M. Maxwell, Matthew J. Witt, Gaspard Abitsi, Marie Pierre Aboro, Pierre Didier Agamboue, Georges Mba Asseko, Francois Boussamba, Emmanuel Chartain, Micheline Schummer Gnandji, Brice Didier Koumba Mabert

Biological Sciences Faculty Publications

Incidental capture of air‑breathing species in fishing gear is a major source of mortality for many threatened populations. Even when individuals are discarded alive, they may not survive due to direct injury, or due to more cryptic internal physiological injury such as decompression sickness. Post‑release mortality, however, can be difficult to determine. In this pilot study, we deployed survivorship pop‑up archival tags (sPAT) (n = 3) for an air‑breathing species, the olive ridley sea turtle (Lepidochelys olivacea), one of the first studies to do so. We found that at least two of the three turtles survived after being …

Characterizing Habitat Suitability For A Central‐Place Forager In A Dynamic Marine Environment, Dana K. Briscoe, Sabrina Fossette, Kylie L. Scales, Elliott L. Hazen, Steven J. Bograd, Sara M. Maxwell, Elizabeth A. Mchuon, Patrick W. Robibson, Carey Kuhn, Daniel P. Costa, Larry B. Crowder, Rebecca L. Lewison

Biological Sciences Faculty Publications

Characterizing habitat suitability for a marine predator requires an understanding of the environmental heterogeneity and variability over the range in which a population moves during a particular life cycle. Female California sea lions (Zalophus californianus) are central‐place foragers and are particularly constrained while provisioning their young. During this time, habitat selection is a function of prey availability and proximity to the rookery, which has important implications for reproductive and population success. We explore how lactating females may select habitat and respond to environmental variability over broad spatial and temporal scales within the California Current System. We combine near‐real‐time …

High Frequency Temperature Variability Reduces The Risk Of Coral Bleaching, Aryan Safaie, Nyssa J. Silbiger, Timothy R. Mcclanahan, Geno Pawlak, Daniel J. Barshis, James L. Hench, Gareth J. Williams, Kristen A. Davis

Biological Sciences Faculty Publications

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 (km), and is therefore not predictable using conventional remote sensing products. Here, we systematically assess the relationship between in situ measurements of 20 environmental variables, along with seven remotely sensed SST thermal stress metrics, and 81 observed bleaching events at coral reef locations spanning five major reef regions globally. We find that high-frequency temperature variability (i.e., daily temperature range) was the most influential factor in …

The Spatial Context Of “Winning” In Mpa Network Design: Location Matters, Andrew S. Kough, Claire B. Paris, Mark J. Butler Iv

Biological Sciences Faculty Publications

(First paragraph) Chollett et al. (2017) make the case that a local network of marine protected areas (MPAs) enhances fisheries for Caribbean spiny lobster (Panulirus argus) off the coast of Honduras. However, their simulation focused on one ecoregion where self-recruitment is predicted to be among the highest in the Caribbean (Cowen, Paris, & Srinivasan, 2006). The shallow banks and scattered cays of the Honduran-Nicaraguan Rise, separating the Cayman and Colombian basins, create an obstacle to the powerful southern Caribbean jet (Richardson, 2005), fostering an ideal location for topographically steered eddies and larval retention. Local management,whether based on traditional …

Integrating Dynamic Subsurface Habitat Metrics Into Species Distribution Models, Stephanie Brodie, Michael G. Jacox, Steven J. Bograd, Heather Welch, Heidi Dewar, Kylie L. Scales, Sara M. Maxwell, Dana M. Briscoe, Christopher A. Edwards, Larry B. Crowder, Rebecca L. Lewison, Elliott L. Hazen

Biological Sciences Faculty Publications

Species distribution models (SDMs) have become key tools for describing and predicting species habitats. In the marine domain, environmental data used in modeling species distributions are often remotely sensed, and as such have limited capacity for interpreting the vertical structure of the water column, or are sampled in situ, offering minimal spatial and temporal coverage. Advances in ocean models have improved our capacity to explore subsurface ocean features, yet there has been limited integration of such features in SDMs. Using output from a data-assimilative configuration of the Regional Ocean Modeling System, we examine the effect of including dynamic subsurface …

Energy-Rich Mesopelagic Fishes Revealed As A Critical Prey Resource For A Deep-Diving Predator Using Quantitative Fatty Acid Signature Analysis, Chandra Goetsch, Melinda G. Conners, Suzanne M. Budge, Yoko Mitani, William A. Walker, Jeffrey F. Bromaghin, Samantha E. Simmons, Colleen Reichmuth, Daniel P. Costa

Biological Sciences Faculty Publications

Understanding the diet of deep-diving predators can provide essential insight to the trophic structure of the mesopelagic ecosystem. Comprehensive population-level diet estimates are exceptionally difficult to obtain for elusive marine predators due to the logistical challenges involved in observing their feeding behavior and collecting samples for traditional stomach content or fecal analyses. We used quantitative fatty acid signature analysis (QFASA) to estimate the diet composition of a wide-ranging mesopelagic predator, the northern elephant seal (Mirounga angustirostris), across five years. To implement QFASA, we first compiled a library of prey fatty acid (FA) profiles from the mesopelagic eastern North Pacific. Given …

Turning Performance Of Brief Squid Lolliguncula Brevis During Attacks On Shrimp And Fish, Rachel A. Jastrebsky, Ian K. Bartol, Paul S. Krueger

Biological Sciences Faculty Publications

Although squid are generally considered to be effective predators, little is currently known of how squid maneuver and position themselves during prey strikes. In this study, high-speed video and kinematic analyses were used to study attacks by the brief squid Lolliguncula brevis on both shrimp and fish. Squid attack successwas high (>80%) and three behavioral phases were identified: (1) approach, (2) strike and (3) recoil. Lolliguncula brevis demonstrated greater maneuverability (i.e. a smaller length-specific turning radius) and employed more body adjustments (i.e. mantle angle posturing) during approaches toward shrimp versus fish. Squid exhibited higher linear approach/strike velocities and accelerations …

Blubber Transciptome Response To Acute Stress Axis Activation Involves Transient Charges In Adipogenesis And Lipolysis In Fast-Adapted Marine Mammal, J. I. Khudyakov, C. D. Champagne, L. M. Meneghetti, D. E. Crocker

Biological Sciences Faculty Publications

Stress can compromise an animal's ability to conserve metabolic stores and participate in energy-demanding activities that are critical for fitness. Understanding how wild animals, especially those already experiencing physiological extremes (e.g. fasting), regulate stress responses is critical for evaluating the impacts of anthropogenic disturbance on physiology and fitness, key challenges for conservation. However, studies of stress in wildlife are often limited to baseline endocrine measurements and few have investigated stress effects in fasting-adapted species. We examined downstream molecular consequences of hypothalamic-pituitary-adrenal (HPA) axis activation by exogenous adrenocorticotropic hormone (ACTH) in blubber of northern elephant seals due to the ease of …

Informing Marine Protected Area Designation And Management For Nesting Olive Ridley Sea Turtles Using Satellite Tracking, Tiffany M. Dawson, Angela Formia, Pierre D. Agamboué, Georges M. Asseko, François Boussamba, Floriane Cardiec, Emmanuel Chartrain, Philip D. Doherty, J. Michael Fay, Brendan J. Godley, Francis Lambert, Brice D. Koumba Mabert, Jean C. Manfoumbi, Kristian Metcalfe, Gianna Minton, Ivan Ndanga, Jacob Nzegoue, Carmen K. Kouerey Oliwina, Philippe Du Plessis, Guy-Philippe Sounguet, Dominic Tilley, Matthew J. Witt, Sara M. Maxwell

Biological Sciences Faculty Publications

Understanding the horizontal and vertical habitat of olive ridley sea turtles (Lepidochelys olivacea), a threatened species, is critical for determining regions for protection and relevant gear modifications that may effectively reduce bycatch, the largest threat to this species. Satellite transmitters were used to determine the movement and dive behavior of 21 female olive ridley turtles tagged in Pongara National Park, Gabon during the 2012, 2013, and 2015 nesting seasons. A switching state-space model was used to filter the tracking data and categorize the internesting and post-nesting movements. Gridded utilization distribution (UD) home range analysis of tracking data revealed …

Multiple Sensory Modalities Used By Squid In Successful Predator Evasion Throughout Ontogeny, Carly A. York, Ian K. Bartol, Paul S. Kruger

Biological Sciences Faculty Publications

Squid rely on multiple sensory systems for predator detection. In this study we examine the role of two sensory systems, the lateral line analogue and vision, in successful predator evasion throughout ontogeny. Squid Doryteuthis pealeii and Lolliguncula brevis were recorded using high-speed videography in the presence of natural predators under light and dark conditions with their lateral line analogue intact or ablated via a pharmacological technique. Paralarval squid showed reduced escape responses when ablated; however, no differences were found between light and dark conditions in non-ablated paralarvae, as was previously shown in juveniles and adults, indicating that the lateral line …

Turning Performance In Squid And Cuttlefish: Unique Dual-Mode, Muscular Hydrostatic Systems, Rachel A. Jastrebsky, Ian K. Bartol, Paul S. Krueger

Biological Sciences Faculty Publications

Although steady swimming has received considerable attention in prior studies, unsteady swimming movements represent a larger portion of many aquatic animals' locomotive repertoire and have not been examined extensively. Squids and cuttlefishes are cephalopods with unique muscular hydrostat-driven, dual-mode propulsive systems involving paired fins and a pulsed jet. These animals exhibit a wide range of swimming behavior, but turning performance has not been examined quantitatively. Brief squid, Lolliguncula brevis, and dwarf cuttlefish, Sepia bandensis, were filmed during turns using high-speed cameras. Kinematic features were tracked, including the length-specific radius of the turn (R/L), a measure of maneuverability, and …

Volumetric Flow Imaging Reveals The Importance Of Vortex Ring Formation In Squid Swimming Tail-First And Arms-First, Ian K. Bartol, Paul S. Krueger, Rachel A. Jastrebsky, Sheila Williams, Joseph T. Thompson

Biological Sciences Faculty Publications

Squids use a pulsed jet and fin movements to swim both arms-first (forward) and tail-first (backward). Given the complexity of the squid multi-propulsor system, 3D velocimetry techniques are required for the comprehensive study of wake dynamics. Defocusing digital particle tracking velocimetry, a volumetric velocimetry technique, and high-speed videography were used to study arms-first and tail-first swimming of brief squid Lolliguncula brevis over a broad range of speeds [0-10 dorsal mantle lengths (DML) s^-1) in a swim tunnel. Although there was considerable complexity in the wakes of these multi-propulsor swimmers, 3D vortex rings and their derivatives were prominent reoccurring features …