Bio


For the most up to date information, check out www.davidecade.com

Honors & Awards


  • Anne T. and Robert M. Bass Fellowship, Stanford University (2014)
  • Outstanding Achievement Award for High Impact Paper, Hopkins Marine Station (2014-2015)

Professional Education


  • Doctor of Philosophy, Stanford University, BIO-PHD (2019)
  • Master of Arts, Stanford University, ED-MA (2005)
  • Bachelor of Arts, Brown University, Mathematics (2002)
  • Master of Science, Oregon State University, Ocean, Earth and Atmospheric Sciences (2014)

Stanford Advisors


All Publications


  • The effect of group size on individual behavior of bubble-net feeding humpback whales in the southern Gulf of Maine MARINE MAMMAL SCIENCE Mastick, N. C., Wiley, D., Cade, D. E., Ware, C., Parks, S. E., Friedlaender, A. S. 2022

    View details for DOI 10.1111/mms.12905

    View details for Web of Science ID 000740705000001

  • Tools for integrating inertial sensor data with video bio-loggers, including estimation of animal orientation, motion, and position ANIMAL BIOTELEMETRY Cade, D. E., Gough, W. T., Czapanskiy, M. F., Fahlbusch, J. A., Kahane-Rapport, S. R., Linsky, J. J., Nichols, R. C., Oestreich, W. K., Wisniewska, D. M., Friedlaender, A. S., Goldbogen, J. A. 2021; 9 (1)
  • Scaling of oscillatory kinematics and Froude efficiency in baleen whales. The Journal of experimental biology Gough, W. T., Smith, H. J., Savoca, M. S., Czapanskiy, M. F., Fish, F. E., Potvin, J., Bierlich, K. C., Cade, D. E., Clemente, J. D., Kennedy, J., Segre, P., Stanworth, A., Weir, C., Goldbogen, J. A. 2021

    Abstract

    High efficiency lunate-tail swimming with high-aspect-ratio lifting surfaces has evolved in many vertebrate lineages, from fish to cetaceans. Baleen whales (Mysticeti) are the largest swimming animals that exhibit this locomotor strategy and present an ideal study system to examine how morphology and the kinematics of swimming scale to the largest body sizes. We used data from whale-borne inertial sensors coupled with morphometric measurements from aerial drones to calculate the hydrodynamic performance of oscillatory swimming in six baleen whale species ranging in body length from 5-25m (fin whale, Balaenoptera physalus; Bryde's whale, Balaenoptera edeni; sei whale, Balaenoptera borealis; Antarctic minke whales, Balaenoptera bonaerensis; humpback whales, Megaptera novaeangliae; and blue whales, Balaenoptera musculus). We find that mass-specific thrust increases with both swimming speed and body size. Froude efficiency, defined as the ratio of useful power output to the rate of energy input (Sloop, 1978), generally increased with swimming speed but decreased on average with increasing body size. This finding is contrary to previous results in smaller animals where Froude efficiency increased with body size. Although our empirically-parameterized estimates for swimming baleen whale drag was higher than that of a simple gliding model, oscillatory locomotion at this scale exhibits generally high Froude efficiency as in other adept swimmers. Our results quantify the fine-scale kinematics and estimate the hydrodynamics of routine and energetically expensive swimming modes at the largest scale.

    View details for DOI 10.1242/jeb.237586

    View details for PubMedID 34109418

  • Modelling short-term energetic costs of sonar disturbance to cetaceans using high-resolution foraging data JOURNAL OF APPLIED ECOLOGY Czapanskiy, M. F., Savoca, M. S., Gough, W. T., Segre, P. S., Wisniewska, D. M., Cade, D. E., Goldbogen, J. A. 2021
  • Predator‐scale spatial analysis of intra‐patch prey distribution reveals the energetic drivers of rorqual whale super‐group formation Functional Ecology Cade, D. E., Seakamela , M., Findlay, K. P., Fukunaga , J., Kahane‐Rapport, S. R., Warren, J. D., Calambokidis, J., Fahlbusch, J. A., Friedlaender , A. S., Hazen, E. L., Kotze , D., McCue, S., Meÿer , M., Oestreich , W. K., Oudejans, M. G., Wilke, C., Goldbogen, J. A. 2021

    View details for DOI 10.1111/1365-2435.13763

  • Context-dependent variability in the predicted daily energetic costs of disturbance for blue whales. Conservation physiology Pirotta, E. n., Booth, C. G., Cade, D. E., Calambokidis, J. n., Costa, D. P., Fahlbusch, J. A., Friedlaender, A. S., Goldbogen, J. A., Harwood, J. n., Hazen, E. L., New, L. n., Southall, B. L. 2021; 9 (1): coaa137

    Abstract

    Assessing the long-term consequences of sub-lethal anthropogenic disturbance on wildlife populations requires integrating data on fine-scale individual behavior and physiology into spatially and temporally broader, population-level inference. A typical behavioral response to disturbance is the cessation of foraging, which can be translated into a common metric of energetic cost. However, this necessitates detailed empirical information on baseline movements, activity budgets, feeding rates and energy intake, as well as the probability of an individual responding to the disturbance-inducing stressor within different exposure contexts. Here, we integrated data from blue whales (Balaenoptera musculus) experimentally exposed to military active sonar signals with fine-scale measurements of baseline behavior over multiple days or weeks obtained from accelerometry loggers, telemetry tracking and prey sampling. Specifically, we developed daily simulations of movement, feeding behavior and exposure to localized sonar events of increasing duration and intensity and predicted the effects of this disturbance source on the daily energy intake of an individual. Activity budgets and movements were highly variable in space and time and among individuals, resulting in large variability in predicted energetic intake and costs. In half of our simulations, an individual's energy intake was unaffected by the simulated source. However, some individuals lost their entire daily energy intake under brief or weak exposure scenarios. Given this large variation, population-level models will have to assess the consequences of the entire distribution of energetic costs, rather than only consider single summary statistics. The shape of the exposure-response functions also strongly influenced predictions, reinforcing the need for contextually explicit experiments and improved mechanistic understanding of the processes driving behavioral and physiological responses to disturbance. This study presents a robust approach for integrating different types of empirical information to assess the effects of disturbance at spatio-temporal and ecological scales that are relevant to management and conservation.

    View details for DOI 10.1093/conphys/coaa137

    View details for PubMedID 33505702

    View details for PubMedCentralID PMC7816799

  • Remoras pick where they stick on blue whales. The Journal of experimental biology Flammang, B. E., Marras, S., Anderson, E. J., Lehmkuhl, O., Mukherjee, A., Cade, D. E., Beckert, M., Nadler, J. H., Houzeaux, G., Vazquez, M., Amplo, H. E., Calambokidis, J., Friedlaender, A. S., Goldbogen, J. A. 2020; 223 (Pt 20)

    Abstract

    Animal-borne video recordings from blue whales in the open ocean show that remoras preferentially adhere to specific regions on the surface of the whale. Using empirical and computational fluid dynamics analyses, we show that remora attachment was specific to regions of separating flow and wakes caused by surface features on the whale. Adhesion at these locations offers remoras drag reduction of up to 71-84% compared with the freestream. Remoras were observed to move freely along the surface of the whale using skimming and sliding behaviors. Skimming provided drag reduction as high as 50-72% at some locations for some remora sizes, but little to none was available in regions where few to no remoras were observed. Experimental work suggests that the Venturi effect may help remoras stay near the whale while skimming. Understanding the flow environment around a swimming blue whale will inform the placement of biosensor tags to increase attachment time for extended ecological monitoring.

    View details for DOI 10.1242/jeb.226654

    View details for PubMedID 33115921

  • The scale of the whale: using video-tag data to evaluate sea-surface ice concentration from the perspective of individual Antarctic minke whales ANIMAL BIOTELEMETRY Linsky, J. J., Wilson, N., Cade, D. E., Goldbogen, J. A., Johnston, D. W., Friedlaender, A. S. 2020; 8 (1)
  • A perfectly inelastic collision: Bulk prey engulfment by baleen whales and dynamical implications for the world's largest cetaceans AMERICAN JOURNAL OF PHYSICS Potvin, J., Cade, D. E., Werth, A. J., Shadwick, R. E., Goldbogen, J. A. 2020; 88 (10): 851–63

    View details for DOI 10.1119/10.0001771

    View details for Web of Science ID 000571786400010

  • Animal-Borne Metrics Enable Acoustic Detection of Blue Whale Migration. Current biology : CB Oestreich, W. K., Fahlbusch, J. A., Cade, D. E., Calambokidis, J., Margolina, T., Joseph, J., Friedlaender, A. S., McKenna, M. F., Stimpert, A. K., Southall, B. L., Goldbogen, J. A., Ryan, J. P. 2020

    Abstract

    Linking individual and population scales is fundamental to many concepts in ecology [1], including migration [2, 3]. This behavior is a critical [4] yet increasingly threatened [5] part of the life history of diverse organisms. Research on migratory behavior is constrained by observational scale [2], limiting ecological understanding and precise management of migratory populations in expansive, inaccessible marine ecosystems [6]. This knowledge gap is magnified for dispersed oceanic predators such as endangered blue whales (Balaenoptera musculus). As capital breeders, blue whales migrate vast distances annually between foraging and breeding grounds, and their population fitness depends on synchrony of migration with phenology of prey populations [7, 8]. Despite previous studies of individual-level blue whale vocal behavior via bio-logging [9, 10] and population-level acoustic presence via passive acoustic monitoring [11], detection of the life history transition from foraging to migration remains challenging. Here, we integrate direct high-resolution measures of individual behavior and continuous broad-scale acoustic monitoring of regional song production (Figure1A) to identify an acoustic signature of the transition from foraging to migration in the Northeast Pacific population. We find that foraging blue whales sing primarily at night, whereas migratory whales sing primarily during the day. The ability to acoustically detect population-level transitions in behavior provides a tool to more comprehensively study the life history, fitness, and plasticity of population behavior in a dispersed, capital breeding population. Real-time detection of this behavioral signal can also inform dynamic management efforts [12] to mitigate anthropogenic threats to this endangered population [13, 14]).

    View details for DOI 10.1016/j.cub.2020.08.105

    View details for PubMedID 33007246

  • An Algorithmic Approach to Natural Behavior. Current biology : CB Hein, A. M., Altshuler, D. L., Cade, D. E., Liao, J. C., Martin, B. T., Taylor, G. K. 2020; 30 (11): R663–R675

    Abstract

    Uncovering the mechanisms and implications of natural behavior is a goal that unites many fields of biology. Yet, the diversity, flexibility, and multi-scale nature of these behaviors often make understanding elusive. Here, we review studies of animal pursuit and evasion - two special classes of behavior where theory-driven experiments and new modeling techniques are beginning to uncover the general control principles underlying natural behavior. A key finding of these studies is that intricate sequences of pursuit and evasion behavior can often be constructed through simple, repeatable rules that link sensory input to motor output: we refer to these rules as behavioral algorithms. Identifying and mathematically characterizing these algorithms has led to important insights, including the discovery of guidance rules that attacking predators use to intercept mobile prey, and coordinated neural and biomechanical mechanisms that animals use to avoid impending collisions. Here, we argue that algorithms provide a good starting point for studies of natural behavior more generally. Rather than beginning at the neural or ecological levels of organization, we advocate starting in the middle, where the algorithms that link sensory input to behavioral output can provide a solid foundation from which to explore both the implementation and the ecological outcomes of behavior. We review insights that have been gained through such an algorithmic approach to pursuit and evasion behaviors. From these, we synthesize theoretical principles and lay out key modeling tools needed to apply an algorithmic approach to the study of other complex natural behaviors.

    View details for DOI 10.1016/j.cub.2020.04.018

    View details for PubMedID 32516620

  • Whale sharks increase swimming effort while filter feeding, but appear to maintain high foraging efficiencies. The Journal of experimental biology Cade, D. E., Levenson, J. J., Cooper, R., de la Parra, R., Webb, D. H., Dove, A. D. 2020

    Abstract

    Whale sharks (Rhincodon typus Smith 1828) - the largest extant fish species - reside in tropical environments, making them an exception to the general rule that animal size increases with latitude. How this largest fish thrives in tropical environments that promote high metabolism but support less robust zooplankton communities has not been sufficiently explained. We used open-source inertial measurement units (IMU) to log 397 hours of whale shark behavior in Yucatan, Mexico, at a site of both active feeding and intense wildlife tourism. Here we show that the strategies employed by whale sharks to compensate for the increased drag of an open mouth are similar to ram-feeders five orders of magnitude smaller and one order of magnitude larger. Presumed feeding constituted 20% of the total time budget of four sharks, with individual feeding bouts lasting up to 11 consecutive hrs. Compared to normal, sub-surface swimming, three sharks increased their stroke rate and amplitude while surface feeding, while one shark that fed at depth did not demonstrate a greatly increased energetic cost. Additionally, based on time-depth budgets, we estimate that aerial surveys of shark populations should consider including a correction factor of 3 to account for the proportion of daylight hours that sharks are not visible at the surface. With foraging bouts generally lasting several hours, interruptions to foraging during critical feeding periods may represent substantial energetic costs to these endangered species, and this study presents baseline data from which management decisions affecting tourist interactions with whale sharks may be made.

    View details for DOI 10.1242/jeb.224402

    View details for PubMedID 32366692

  • Energetic and physical limitations on the breaching performance of large whales. eLife Segre, P. S., Potvin, J., Cade, D. E., Calambokidis, J., Di Clemente, J., Fish, F. E., Friedlaender, A. S., Gough, W. T., Kahane-Rapport, S. R., Oliveira, C., Parks, S. E., Penry, G. S., Simon, M., Stimpert, A. K., Wiley, D. N., Bierlich, K. C., Madsen, P. T., Goldbogen, J. A. 2020; 9

    Abstract

    The considerable power needed for large whales to leap out of the water may represent the single most expensive burst maneuver found in nature. However, the mechanics and energetic costs associated with the breaching behaviors of large whales remain poorly understood. In this study we deployed whale-borne tags to measure the kinematics of breaching to test the hypothesis that these spectacular aerial displays are metabolically expensive. We found that breaching whales use variable underwater trajectories, and that high-emergence breaches are faster and require more energy than predatory lunges. The most expensive breaches approach the upper limits of vertebrate muscle performance, and the energetic cost of breaching is high enough that repeated breaching events may serve as honest signaling of body condition. Furthermore, the confluence of muscle contractile properties, hydrodynamics, and the high speeds required likely impose an upper limit to the body size and effectiveness of breaching whales.

    View details for DOI 10.7554/eLife.51760

    View details for PubMedID 32159511

  • From a calf's perspective: humpback whale nursing behavior on two US feeding grounds PEERJ Tackaberry, J. E., Cade, D. E., Goldbogen, J. A., Wiley, D. N., Friedlaender, A. S., Stimpert, A. K. 2020; 8: e8538

    Abstract

    Nursing influences growth rate and overall health of mammals; however, the behavior is difficult to study in wild cetaceans because it occurs below the surface and can thus be misidentified from surface observations. Nursing has been observed in humpback whales on the breeding and calving grounds, but the behavior remains unstudied on the feeding grounds. We instrumented three dependent calves (four total deployments) with combined video and 3D-accelerometer data loggers (CATS) on two United States feeding grounds to document nursing events. Two associated mothers were also tagged to determine if behavior diagnostic of nursing was evident in the mother's movement. Animal-borne video was manually analyzed and the average duration of successful nursing events was 23 s (±7 sd, n = 11). Nursing occurred at depths between 4.1-64.4 m (along the seafloor) and in close temporal proximity to foraging events by the mothers, but could not be predicted solely by relative positions of mother and calf. When combining all calf deployments, successful nursing was documented eleven times; totaling only 0.3% of 21.0 hours of video. During nursing events, calves had higher overall dynamic body acceleration (ODBA) and increased fluke-stroke rate (FSR) compared to non-nursing segments (Mixed effect models, ODBA: F1,107 = 13.57756, p = 0.0004, FSR: F1,107 = 32.31018, p < 0.0001). In contrast, mothers had lower ODBA and reduced FSR during nursing events compared to non-nursing segments. These data provide the first characterization of accelerometer data of humpback whale nursing confirmed by animal-borne video tags and the first analysis of nursing events on feeding grounds. This is an important step in understanding the energetic consequences of lactation while foraging.

    View details for DOI 10.7717/peerj.8538

    View details for Web of Science ID 000517940900003

    View details for PubMedID 32181052

    View details for PubMedCentralID PMC7060748

  • Whale sharks increase swimming effort while filter feeding, but appear to maintain high foraging efficiencies. The Journal of experimental biology Cade, D. E., Levenson, J. J., Cooper, R., de la Parra, R., Webb, D. H., Dove, A. D. 2020

    Abstract

    Whale sharks (Rhincodon typus Smith 1828) - the largest extant fish species - reside in tropical environments, making them an exception to the general rule that animal size increases with latitude. How this largest fish thrives in tropical environments that promote high metabolism but support less robust zooplankton communities has not been sufficiently explained. We used open-source inertial measurement units (IMU) to log 397 hours of whale shark behavior in Yucatan, Mexico, at a site of both active feeding and intense wildlife tourism. Here we show that the strategies employed by whale sharks to compensate for the increased drag of an open mouth are similar to ram-feeders five orders of magnitude smaller and one order of magnitude larger. Presumed feeding constituted 20% of the total time budget of four sharks, with individual feeding bouts lasting up to 11 consecutive hrs. Compared to normal, sub-surface swimming, three sharks increased their stroke rate and amplitude while surface feeding, while one shark that fed at depth did not demonstrate a greatly increased energetic cost. Additionally, based on time-depth budgets, we estimate that aerial surveys of shark populations should consider including a correction factor of 3 to account for the proportion of daylight hours that sharks are not visible at the surface. With foraging bouts generally lasting several hours, interruptions to foraging during critical feeding periods may represent substantial energetic costs to these endangered species, and this study presents baseline data from which management decisions affecting tourist interactions with whale sharks may be made.

    View details for DOI 10.1242/jeb.224402

    View details for PubMedID 34005603

  • Behavioral responses of individual blue whales (Balaenoptera musculus) to mid-frequency military sonar. The Journal of experimental biology Southall, B. L., DeRuiter, S. L., Friedlaender, A., Stimpert, A. K., Goldbogen, J. A., Hazen, E., Casey, C., Fregosi, S., Cade, D. E., Allen, A. N., Harris, C. M., Schorr, G., Moretti, D., Guan, S., Calambokidis, J. 2019; 222 (Pt 5)

    Abstract

    This study measured the degree of behavioral responses in blue whales (Balaenoptera musculus) to controlled noise exposure off the southern California coast. High-resolution movement and passive acoustic data were obtained from non-invasive archival tags (n=42) whereas surface positions were obtained with visual focal follows. Controlled exposure experiments (CEEs) were used to obtain direct behavioral measurements before, during and after simulated and operational military mid-frequency active sonar (MFAS), pseudorandom noise (PRN) and controls (no noise exposure). For a subset of deep-feeding animals (n=21), active acoustic measurements of prey were obtained and used as contextual covariates in response analyses. To investigate potential behavioral changes within individuals as a function of controlled noise exposure conditions, two parallel analyses of time-series data for selected behavioral parameters (e.g. diving, horizontal movement and feeding) were conducted. This included expert scoring of responses according to a specified behavioral severity rating paradigm and quantitative change-point analyses using Mahalanobis distance statistics. Both methods identified clear changes in some conditions. More than 50% of blue whales in deep-feeding states responded during CEEs, whereas no changes in behavior were identified in shallow-feeding blue whales. Overall, responses were generally brief, of low to moderate severity, and highly dependent on exposure context such as behavioral state, source-to-whale horizontal range and prey availability. Response probability did not follow a simple exposure-response model based on received exposure level. These results, in combination with additional analytical methods to investigate different aspects of potential responses within and among individuals, provide a comprehensive evaluation of how free-ranging blue whales responded to mid-frequency military sonar.

    View details for PubMedID 30833464

  • Behavioral responses of individual blue whales (Balaenoptera musculus) to mid-frequency military sonar JOURNAL OF EXPERIMENTAL BIOLOGY Southall, B. L., DeRuiter, S. L., Friedlaender, A., Stimpert, A. K., Goldbogen, J. A., Hazen, E., Casey, C., Fregosi, S., Cade, D. E., Allen, A. N., Harris, C. M., Schorr, G., Moretti, D., Guan, S., Calambokidis, J. 2019; 222 (5)

    View details for DOI 10.1242/jeb.190637

    View details for Web of Science ID 000461414600007

  • Scaling of swimming performance in baleen whales. The Journal of experimental biology Gough, W. T., Segre, P. S., Bierlich, K. C., Cade, D. E., Potvin, J. n., Fish, F. E., Dale, J. n., di Clemente, J. n., Friedlaender, A. S., Johnston, D. W., Kahane-Rapport, S. R., Kennedy, J. n., Long, J. H., Oudejans, M. n., Penry, G. n., Savoca, M. S., Simon, M. n., Videsen, S. K., Visser, F. n., Wiley, D. N., Goldbogen, J. A. 2019

    Abstract

    The scale-dependence of locomotor factors have long been studied in comparative biomechanics, but remain poorly understood for animals at the upper extremes of body size. Rorqual baleen whales include the largest animals, but we lack basic kinematic data about their movements and behavior below the ocean surface. Here we combined morphometrics from aerial drone photogrammetry, whale-borne inertial sensing tag data, and hydrodynamic modeling to study the locomotion of five rorqual species. We quantified changes in tail oscillatory frequency and cruising speed for individual whales spanning a threefold variation in body length, corresponding to an order of magnitude variation in estimated body mass. Our results showed that oscillatory frequency decreases with body length (∝ length-0.53) while cruising speed remains roughly invariant (∝ length0.08) at 2 m s-1 We compared these measured results for oscillatory frequency against simplified models of an oscillating cantilever beam (∝ length-1) and an optimized oscillating Strouhal vortex generator (∝ length-1). The difference between our length-scaling exponent and the simplified models suggests that animals are often swimming non-optimally in order to feed or perform other routine behaviors. Cruising speed aligned more closely with an estimate of the optimal speed required to minimize the energetic cost of swimming (∝ length0.07). Our results are among the first to elucidate the relationships between both oscillatory frequency and cruising speed and body size for free-swimming animals at the largest scale.

    View details for DOI 10.1242/jeb.204172

    View details for PubMedID 31558588

  • Filtration area scaling and evolution in mysticetes: trophic niche partitioning and the curious cases of sei and pygmy right whales BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY Werth, A. J., Potvin, J., Shadwick, R. E., Jensen, M. M., Cade, D. E., Goldbogen, J. A. 2018; 125 (2): 264–79
  • Determining forward speed from accelerometer jiggle in aquatic environments. The Journal of experimental biology Cade, D. E., Barr, K. R., Calambokidis, J. n., Friedlaender, A. S., Goldbogen, J. A. 2018; 221 (Pt 2)

    Abstract

    How fast animals move is critical to understanding their energetic requirements, locomotor capacity and foraging performance, yet current methods for measuring speed via animal-attached devices are not universally applicable. Here, we present and evaluate a new method that relates forward speed to the stochastic motion of biologging devices as tag jiggle, the amplitude of the tag vibrations as measured by high sample rate accelerometers, increases exponentially with increasing speed. We successfully tested this method in a flow tank using two types of biologging devices and in situ on wild cetaceans spanning ∼3 to >20 m in length using two types of suction cup-attached tag and two types of dart-attached tag. This technique provides some advantages over other approaches for determining speed as it is device-orientation independent and relies only on a pressure sensor and a high sample rate accelerometer, sensors that are nearly universal across biologging device types.

    View details for PubMedID 29191861

  • Determining forward speed from accelerometer jiggle in aquatic environments JOURNAL OF EXPERIMENTAL BIOLOGY Cade, D. E., Barr, K. R., Calambokidis, J., Friedlaender, A. S., Goldbogen, J. A. 2018; 221 (2)

    View details for DOI 10.1242/jeb.170449

    View details for Web of Science ID 000424076300018

  • Context-dependent lateralized feeding strategies in blue whales CURRENT BIOLOGY Friedlaender, A. S., Herbert-Read, J. E., Hazen, E. L., Cade, D. E., Calambokidis, J., Southall, B. L., Stimpert, A. K., Goldbogen, J. A. 2017; 27 (22): R1206–R1208

    Abstract

    Lateralized behaviors benefit individuals by increasing task efficiency in foraging and anti-predator behaviors [1-4]. The conventional lateralization paradigm suggests individuals are left or right lateralized, although the direction of this laterality can vary for different tasks (e.g. foraging or predator inspection/avoidance). By fitting tri-axial movement sensors to blue whales (Balaenoptera musculus), and by recording the direction and size of their rolls during lunge feeding events, we show how these animals differ from such a paradigm. The strength and direction of individuals' lateralization were related to where and how the whales were feeding in the water column. Smaller rolls (≤180°) predominantly occurred at depth (>70 m), with whales being more likely to rotate clockwise around their longest axis (right lateralized). Larger rolls (>180°), conversely, occurred more often at shallower depths (<70 m) and were more likely to be performed anti-clockwise (left lateralized). More acrobatic rolls are typically used to target small, less dense krill patches near the water's surface [5,6], and we posit that the specialization of lateralized feeding strategies may enhance foraging efficiency in environments with heterogeneous prey distributions.

    View details for PubMedID 29161554

  • How Baleen Whales Feed: The Biomechanics of Engulfment and Filtration. Annual review of marine science Goldbogen, J. A., Cade, D. E., Calambokidis, J., Friedlaender, A. S., Potvin, J., Segre, P. S., Werth, A. J. 2017; 9: 367-386

    Abstract

    Baleen whales are gigantic obligate filter feeders that exploit aggregations of small-bodied prey in littoral, epipelagic, and mesopelagic ecosystems. At the extreme of maximum body size observed among mammals, baleen whales exhibit a unique combination of high overall energetic demands and low mass-specific metabolic rates. As a result, most baleen whale species have evolved filter-feeding mechanisms and foraging strategies that take advantage of seasonally abundant yet patchily and ephemerally distributed prey resources. New methodologies consisting of multi-sensor tags, active acoustic prey mapping, and hydrodynamic modeling have revolutionized our ability to study the physiology and ecology of baleen whale feeding mechanisms. Here, we review the current state of the field by exploring several hypotheses that aim to explain how baleen whales feed. Despite significant advances, major questions remain about the processes that underlie these extreme feeding mechanisms, which enabled the evolution of the largest animals of all time.

    View details for DOI 10.1146/annurev-marine-122414-033905

    View details for PubMedID 27620830

  • Humpback whale "super-groups" - A novel low-latitude feeding behaviour of Southern Hemisphere humpback whales (Megaptera novaeangliae) in the Benguela Upwelling System. PloS one Findlay, K. P., Seakamela, S. M., Meÿer, M. A., Kirkman, S. P., Barendse, J., Cade, D. E., Hurwitz, D., Kennedy, A. S., Kotze, P. G., McCue, S. A., Thornton, M., Vargas-Fonseca, O. A., Wilke, C. G. 2017; 12 (3)

    Abstract

    Southern Hemisphere humpback whales (Megaptera novaeangliae) generally undertake annual migrations from polar summer feeding grounds to winter calving and nursery grounds in subtropical and tropical coastal waters. Evidence for such migrations arises from seasonality of historic whaling catches by latitude, Discovery and natural mark returns, and results of satellite tagging studies. Feeding is generally believed to be limited to the southern polar region, where Antarctic krill (Euphausia superba) has been identified as the primary prey item. Non-migrations and / or suspended migrations to the polar feeding grounds have previously been reported from a summer presence of whales in the Benguela System, where feeding on euphausiids (E. lucens), hyperiid amphipods (Themisto gaudichaudii), mantis shrimp (Pterygosquilla armata capensis) and clupeid fish has been described. Three recent research cruises (in October/November 2011, October/November 2014 and October/November 2015) identified large tightly-spaced groups (20 to 200 individuals) of feeding humpback whales aggregated over at least a one-month period across a 220 nautical mile region of the southern Benguela System. Feeding behaviour was identified by lunges, strong milling and repetitive and consecutive diving behaviours, associated bird and seal feeding, defecations and the pungent "fishy" smell of whale blows. Although no dedicated prey sampling could be carried out within the tightly spaced feeding aggregations, observations of E. lucens in the region of groups and the full stomach contents of mantis shrimp from both a co-occurring predatory fish species (Thyrsites atun) and one entangled humpback whale mortality suggest these may be the primary prey items of at least some of the feeding aggregations. Reasons for this recent novel behaviour pattern remain speculative, but may relate to increasing summer humpback whale abundance in the region. These novel, predictable, inter-annual, low latitude feeding events provide considerable potential for further investigation of Southern Hemisphere humpback feeding behaviours in these relatively accessible low-latitude waters.

    View details for DOI 10.1371/journal.pone.0172002

    View details for PubMedID 28249036

    View details for PubMedCentralID PMC5332018

  • Hydrodynamic properties of fin whale flippers predict maximum rolling performance. journal of experimental biology Segre, P. S., Cade, D. E., Fish, F. E., Potvin, J., Allen, A. N., Calambokidis, J., Friedlaender, A. S., Goldbogen, J. A. 2016; 219: 3315-3320

    Abstract

    Maneuverability is one of the most important and least understood aspects of animal locomotion. The hydrofoil-like flippers of cetaceans are thought to function as control surfaces that effect maneuvers, but quantitative tests of this hypothesis have been lacking. Here, we constructed a simple hydrodynamic model to predict the longitudinal-axis roll performance of fin whales, and we tested its predictions against kinematic data recorded by on-board movement sensors from 27 free-swimming fin whales. We found that for a given swimming speed and roll excursion, the roll velocity of fin whales calculated from our field data agrees well with that predicted by our hydrodynamic model. Although fluke and body torsion may further influence performance, our results indicate that lift generated by the flippers is sufficient to drive most of the longitudinal-axis rolls used by fin whales for feeding and maneuvering.

    View details for PubMedID 27591304

  • Kinematic Diversity in Rorqual Whale Feeding Mechanisms CURRENT BIOLOGY Cade, D. E., Friedlaender, A. S., Calambokidis, J., Goldbogen, J. A. 2016; 26 (19): 2617-2624

    Abstract

    Rorqual whales exhibit an extreme lunge filter-feeding strategy characterized by acceleration to high speed and engulfment of a large volume of prey-laden water [1-4]. Although tagging studies have quantified the kinematics of lunge feeding, the timing of engulfment relative to body acceleration has been modeled conflictingly because it could never be directly measured [5-7]. The temporal coordination of these processes has a major impact on the hydrodynamics and energetics of this high-cost feeding strategy [5-9]. If engulfment and body acceleration are temporally distinct, the overall cost of this dynamic feeding event would be minimized. However, greater temporal overlap of these two phases would theoretically result in higher drag and greater energetic costs. To address this discrepancy, we used animal-borne synchronized video and 3D movement sensors to quantify the kinematics of both the skull and body during feeding events. Krill-feeding blue and humpback whales exhibited temporally distinct acceleration and engulfment phases, with humpback whales reaching maximum gape earlier than blue whales. In these whales, engulfment coincided largely with body deceleration; however, humpback whales pursuing more agile fish demonstrated highly variable coordination of skull and body kinematics in the context of complex prey-herding techniques. These data suggest that rorquals modulate the coordination of acceleration and engulfment to optimize foraging efficiency by minimizing locomotor costs and maximizing prey capture. Moreover, this newfound kinematic diversity observed among rorquals indicates that the energetic efficiency of foraging is driven both by the whale's engulfment capacity and the comparative locomotor capabilities of predator and prey. VIDEO ABSTRACT.

    View details for DOI 10.1016/j.cub.2016.07.037

    View details for Web of Science ID 000385690800022

    View details for PubMedID 27666966

  • Insights into the Underwater Behavior, Species Interactions, and Biomechanics of Baleen Whales using Suction-Cup Attached Video and Inertial Sensors Goldbogen, J., Cade, D., Calambokidis, J., Stimpert, A., Friedlaender, A. FEDERATION AMER SOC EXP BIOL. 2016
  • Depths, migration rates and environmental associations of acoustic scattering layers in the Gulf of California DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS Cade, D. E., Benoit-Bird, K. J. 2015; 102: 78-89
  • An automatic and quantitative approach to the detection and tracking of acoustic scattering layers LIMNOLOGY AND OCEANOGRAPHY-METHODS Cade, D. E., Benoit-Bird, K. J. 2014; 12: 742-756