Adrian Gleiss

Murdoch University · School of Veterinary and Life Sciences

Locomotion is one of the major energetic costs faced by animals and various strategies have evolved to reduce its cost. Birds use interspersed periods of flapping and gliding to reduce the mechanical requirements of level flight while undergoing cyclical changes in flight altitude, known as undulating flight. Here we equipped free-ranging marine ve...

1. The energetic costs of different behaviours are critical in modulating the behavioural ecology of free-living animals. Despite this, measurement of energy expenditure in the field has proved difficult. 2. A new method with broad application for field studies has been proposed for determining the rate at which animals expend energy, based on meas...

1. A primary determinant of movement strategies is travel speed, which modulates both power consumption and distance travelled and thus varies according to ecological circumstance. Many dense animals moving in 3D media face costs according to their movement trajectory and it should therefore equally be optimized according to circumstance. 2. We in...

An animal's movement is influenced by a plethora of internal and external factors, leading to individual‐ and habitat‐specific movement characteristics. This plasticity is thought to allow individuals to exploit diverse environments efficiently. We tested whether the movement characteristics of white sharks Carcharodon carcharias differ across onto...

Increased environmental temperatures result in greater energy demands for ectotherms, however, it is currently not clear if these energy demands can effectively be met by increased foraging effort. Here, we tested the temperature dependence of foraging effort and metabolic rate in an aquatic ectotherm across its entire natural thermal range. We dev...

Baitfishes may aggregate around megafauna such as whale sharks (Rhincodon typus) to gain protection from larger predatory fishes. Here, we used videos from deployments of animal-borne cameras on whale sharks and provided by tourism operators at Ningaloo Reef in Western Australia to document large schools of trevally (Carangidae spp.) consuming enti...

Conservation of threatened species and anthropogenic threat mitigation commonly rely on spatially managed areas selected according to habitat preference. Since the impact of threats can be behaviour‐specific, such information could be incorporated into spatial management to improve conservation outcomes. However, collecting spatially explicit behav...

Wildlife tourism is one of the fastest-growing sectors of the tourism industry, where feeding animals is often applied to increase the probability of up-close encounters. However, directly feeding wildlife can cause behavioural, ecological, and physiological changes in the target species. In Oslob, Philippines, whale shark (Rhincodon typus) tourism...

Home range size and metabolic rate of animals are expected to scale with body mass at similar rates; with home ranges expanding to meet increased metabolic requirements. This expectation has widely been tested using lab-derived estimates of basal metabolic rate as proxies for field energy requirements, however, it is unclear if existing theory alig...

Hammerhead sharks hold their breath when diving to regulate body temperature.

An animal’s movement is influenced by a plethora of internal and external factors, leading to individual- and habitat-specific movement characteristics. This plasticity is thought to allow individuals to exploit diverse environments efficiently. We tested if the movement characteristics of white sharks Carcharodon carcharias differ across ontogeny...

Knowledge of the three-dimensional movement patterns of elasmobranchs is vital to understand their ecological roles and exposure to anthropogenic pressures. To date, comparative studies among species at global scales have mostly focused on horizontal movements. Our study addresses the knowledge gap of vertical movements by compiling the first globa...

Niche partitioning of time, space or resources is considered the key to allowing the coexistence of competitor species, and particularly guilds of predators. However, the extent to which these processes occur in marine systems is poorly understood due to the difficulty in studying fine-scale movements and activity patterns in mobile underwater spec...

Underwater visual surveys represent an essential component of coastal marine research and play a crucial role in supporting the management of marine systems. However, logistical and financial considerations can limit the availability of survey data in some systems. While biologging camera tag devices are being attached to an increasing diversity of...

Background Tri-axial accelerometers have been used to remotely describe and identify in situ behaviours of a range of animals without requiring direct observations. Datasets collected from these accelerometers (i.e. acceleration, body position) are often large, requiring development of semi-automated analyses to classify behaviours. Marine fishes e...

• Sawfishes (Family: Pristidae) are one of the most imperilled fish families worldwide. There is an increasingly urgent need to better understand the biology, ecology, and population status of the five sawfish species to develop more effective conservation measures. The dwarf sawfish, Pristis clavata, is one of the least researched members of the p...

COVID-19 restrictions have led to an unprecedented global hiatus in anthropogenic activities, providing a unique opportunity to assess human impact on biological systems. Here, we describe how a national network of acoustic tracking receivers can be leveraged to assess the effects of human activity on animal movement and space use during such globa...

Bio‐logging data obtained by tagging animals are key to addressing global conservation challenges. However, the many thousands of existing bio‐logging datasets are not easily discoverable, universally comparable, nor readily accessible through existing repositories and across platforms, slowing down ecological research and effective management. A s...

Predation is a primary selection pressure contributing to both the morphological and behavioral adaptations of organisms (Brodie 1983, Lima and Dill 1990). However, studying the anti‐predator behaviors of aquatic taxa such as sea turtles is currently limited by the difficulty of observing the natural behaviors of free‐ranging individuals at sea (He...

Dynamic Body Acceleration (DBA), measured through animal-attached tags, has emerged as a powerful method for estimating field metabolic rates of free-ranging individuals. Following respirometry to calibrate oxygen consumption rate ( M O 2 ) with DBA under controlled conditions, predictive models can be applied to DBA data collected from free-rangin...

The increase in severity and occurrence of drought from environmental change poses a significant threat to freshwater ecosystems. However, many of the mechanisms by which periodic drought affects aquatic animals are poorly understood. Here we integrated physical, physiological, and behavioural measurements made in the field over a twelve-year perio...

How animals partition activity throughout the day is influenced by processes that affect supply and obtainability of resources. However, as resource supply and usability are often entrained by the same diurnal pattern, it has been difficult to disentangle their relative importance. Given the strong influence that tide has on the distribution and ac...

Understanding how the movement and habitat use of fishes are influenced by flow regimes is important in sustainably managing river ecosystems, particularly in regions undergoing drying due to climate change. Here, we aimed to determine how the movement of a freshwater fish from refuge pools is influenced by discharge and environmental variables in...

Tiger sharks, Galeocerdo cuvier , are a keystone, top-order predator that are assumed to engage in cost-efficient movement and foraging patterns. To investigate the extent to which oscillatory diving by tiger sharks conform to these patterns, we used a biologging approach to model their cost of transport. High-resolution biologging tags with tri-ax...

Life history, reproduction, and survival are fundamentally linked to energy expenditure and acquisition. Dynamic Body Acceleration (DBA), measured through animal-attached data-loggers or transmitters, has emerged as a powerful method for estimating field metabolic rates of free-ranging individuals. After using respirometry to calibrate oxygen consu...

Environments where extreme temperatures and low productivity occur introduce energetically challenging circumstances that may be exacerbated by climate change. Despite the strong link between metabolism and temperature in ectotherms, there is a paucity of data regarding how the metabolic ecology of species affects growth and fitness under such circ...

This study developed a portable, low‐cost field respirometer for measuring oxygen consumption rates of large‐bodied fishes. The respirometer performed well in laboratory tests and was used to measure the oxygen consumption rates ( O2) of bull sharks Carcharhinus leucas (mean: 249.21 ± 58.10 mg O2 kg⁻¹ h⁻¹ at 27.05°C). Interspecific comparisons and...

In tunas, the slow-twitch red muscle, which has an elevated temperature, powers thunniform locomotion, a stiff-bodied swimming style. The anatomical placement and operating temperatures of red muscle vary widely among teleosts: in tunas, the red muscle is located centrally in the body, adjacent to the spine, and maintains an elevated temperature. I...

Temperature is one of the most influential drivers of physiological performance and behaviour in ectotherms, determining how these animals relate to their ecosystems and their ability to succeed in particular habitats. Here, we analysed the largest set of acceleration data compiled to date for elasmobranchs to examine the relationship between volit...

The freshwater sawfish (Pristis pristis) was recently listed as the most Evolutionarily Distinct and Globally Endangered (EDGE) animal. The Fitzroy River in the remote Kimberley region of north-western Australia represents a significant stronghold for the species, which uses the freshwater reaches of the river as a nursery. There is also mounting p...

Background The study of bioenergetics, kinematics, and behavior in free-ranging animals has been transformed through the increasing use of biologging devices that sample motion intensively with high-resolution sensors. Overall dynamic body acceleration (ODBA) derived from biologging tags has been validated as a proxy of locomotor energy expenditure...

Large epipelagic fishes (> 30 kg maximum size) are known to display a variety of patterns of vertical movement. Although advances in the affordability and sophistication of electronic tags now allows researchers to routinely document these patterns, there is no standardised approach to classify these behaviours and investigate their physical and bi...

Tunas possess a range of physiological and mechanical adaptations geared towards high-performance swimming that are of considerable interest to physiologists, ecologists and engineers. Advances in biologging have provided significant improvements in understanding tuna migrations and vertical movement patterns, yet our understanding of the locomotio...

An understanding of the role that large marine predators play in structuring trophic flow and nutrient cycling in marine ecosystems requires knowledge of their fine-scale (m-km) movement behaviors. In this study, biologging tags were used to reveal new insights into the three-dimensional fine-scale movement ecology of tiger sharks (Galeocerdo cuvie...

Traditional forms of marine wildlife research are often restricted to coarse telemetry or surface-based observations, limiting information on fine-scale behaviours such as predator–prey events and interactions with habitat features. We use contemporary animal-attached cameras with motion sensing dataloggers, to reveal novel behaviours by white shar...

Bluefin tunas are highly specialized fish with unique hydrodynamic designs and physiological traits. In this study, we present results in a captive population that demonstrate strong effects of ambient temperature on the tail beat frequency and swimming speed of a pelagic fish in both pre- and post-prandial states. We measured the responses of a ra...

Understanding the behaviours of free-ranging animals over biologically meaningful time scales (e.g., diel, tidal, lunar, seasonal, annual) gives unique insight into their ecology. Bio-logging tools such as accelerometers allow the remote study of elusive or inaccessible animals by recording high resolution movement data. Machine learning (ML) is be...

The expanding use of biologging tags in studies of shark movement provides an opportunity to elucidate the context and drivers of fine-scale movement patterns of these predators. In May 2017, we deployed high-resolution biologging tags on four mature female sandbar sharks Carcharhinus plumbeus at Ningaloo Reef for durations ranging between 13 and 2...

This study reports on the metabolic rate of the blacktip shark Carcharhinus limbatus and the energetic costs of external tag attachment. Metabolic rates, swimming speed and tail‐beat (BT) frequency were measured in a static respirometer with untagged animals and animals equipped with a small data logger. Tagged sharks showed significantly higher ro...

Large-bodied pelagic ectotherms such as sharks need to maintain internal temperatures within a favourable range in order to maximise performance and be cost-efficient foragers. This implies that behavioural thermoregulation should be a key feature of the movements of these animals, although field evidence is limited. We used depth and temperature a...

Discerning behaviours of free-ranging animals allows for quantifcation of their activity budget, providing important insight into ecology. Over recent years, accelerometers have been used to unveil the cryptic lives of animals. The increased ability of accelerometers to store large quantities of high resolution data has prompted a need for automate...

Measuring the metabolic rate of animals is an essential part of understanding their ecology, behaviour and life history. Respirometry is the standard method of measuring metabolism in fish, but different respirometry methods and systems can result in disparate measurements of metabolic rate, a factor often difficult to quantify. Here we directly co...

The whale shark is an ideal flagship species for citizen science projects because of its charismatic nature, its size, and the associated ecotourism ventures focusing on the species at numerous coastal aggregation sites. An online database of whale shark encounters, identifying individuals on the basis of their unique skin patterning, captured almo...

Buoyancy control is a fundamental aspect of aquatic life that has major implications for locomotor performance and ecological niche. Unlike terrestrial animals, the densities of aquatic animals are similar to the supporting fluid, thus even small changes in body density may have profound effects on locomotion. Here, we analysed the body composition...

The largest of the sawfishes is the Critically Endangered green sawfish Pristis zijsron, a species believed to have undergone a major decline (38%) in extent of occurrence. Conservation efforts are hampered by the lack of information on the habitat requirements of this species. We used passive acoustic telemetry to document the movement patterns of...

Knowledge of how an animal uses its habitat is a fundamental component of effective conservation strategies. The Critically Endangered largetooth sawfish Pristis pristis uses rivers and their estuaries as nursery habitats, where it is likely to be exposed to elevated pressures from anthropogenic-induced stresses including fishing (e.g. bycatch, dir...

Estuaries in the Mediterranean climate regions of southern Australia are vulnerable to the effects of anthropogenic pressures and climate change. Many of these systems are affected by eutrophication, water extraction, increased loading of fine sediments and organic matter, hydrological modification, and altered geomorphology and connectivity. In ma...

Circadian rhythms occur widely amongst living organisms, often in response to diel changes in environmental conditions. In aquatic animals, circadian activity is often synchronised with diel changes in the depths individuals occupy and may be related to predator–prey interactions, where the circadian rhythm is determined by ambient light levels, or...

We utilized a unique opportunity to study the growth and bioenergetics of a highly migratory and commercially valuable marine fish under controlled environmental conditions. We maintained yellowfin tuna (Thunnus albacares) in holding tanks throughout a twenty-year period, routinely collecting data on mass and length of individual fish over time. Th...

The ability to produce estimates of the metabolic rate of free-ranging animals is fundamental to the study of their ecology. However, measuring the energy expenditure of animals in the field has proven difficult, especially for aquatic taxa. Accelerometry presents a means of translating metabolic rates measured in the laboratory to individuals stud...

Jellyfish have become a topic of interest of many marine scientists and managers alike due to their conspicuous socio-economic and environmental impacts. However, our knowledge about their “everyday life” remains limited. While electronic tags (transmitters and loggers) have been extensively used to study marine vertebrates for the past 50 years, t...

Fish migrations through riverine systems can be energetically demanding, and the presence of fishways to facilitate upstream passage can add an additional energetic cost that may directly affect fitness. Successful fishway passage is a function of the ability of fish to select appropriate paths and swimming strategies that do not exceed their swimm...

Animals exhibit various physiological and behavioural strategies for minimizing travel costs. Fins of aquatic animals play key roles in efficient travel and, for sharks, the functions of dorsal and pectoral fins are considered well divided: the former assists propulsion and generate lateral hydrodynamic forces during turns and the latter generates...

Shark-mounted video of three S. mokarran swimming at South Bimini Island, Bahamas. Video supplied by Andy B. Casagrande IV.

Shark-mounted video of 295 cm S. mokarran swimming at Batt Reef, Queensland, Australia.

Video of two S. mokarran swimming rolled in public aquaria in the United States.

Supplementary Figures 1-12, Supplementary Tables 1-2, Supplementary Notes 1-5 and Supplementary References

It is a golden age for animal movement studies and so an opportune time to assess priorities for future work. We assembled 40 experts to identify key questions in this field, focussing on marine megafauna, which include a broad range of birds, mammals, reptiles, and fish. Research on these taxa has both underpinned many of the recent technical deve...

It is a golden age for animal movement studies and so an opportune time to assess priorities for future work. We assembled 40 experts to identify key questions in this field, focussing on marine megafauna, which include a broad range of birds, mammals, reptiles, and fish. Research on these taxa has both underpinned many of the recent technical deve...

Background Gathering data on the life of enigmatic animals remains a challenge, despite its important role in biodiversity conservation and management. For many species, biogeographic investigations are largely the result of information that is generated from multiple sources, often over long time-scales, because measuring biogeographic and biologi...

External tags fitted to diving birds can affect them in many ways with the most critical effect being an increase in drag. The effects of transmitters can be even more acute due to the presence of a protruding aerial. The study assesses the impact of PTT antenna on the behaviour and energetics of device-equipped guillemots (Uria aalge) in captivity...

External tags fitted to diving birds can affect them in many ways with the most critical effect being an increase in drag. The effects of transmitters can be even more acute due to the presence of a protruding aerial. The study assesses the impact of PTT antenna on the behaviour and energetics of device-equipped guillemots (Uria aalge) in captivity...

Sharks and other top predators have a substantial impact on their ecosystems through trophically mediated effects, and understanding the scope of this impact is essential to forming an accurate picture of energy flow within an ecosystem. One of the most important factors to consider when assessing a predator's impact on their ecosystem is metabolic...

The swim bladder provides a mechanism for buoyancy regulation in teleosts. However, in certain species, its location can result in an unstable body position, with associated energetic costs assumed for maintaining posture in addition to the energetic demands from swimbladder volume regulation. Direct observations show that some body-compressed, cav...

Many marine species are difficult to study because components of their lifecycles occur solely or partially outside of the observable realm of researchers. Advances in biologging tags have begun to give us glimpses into these unobservable states. However, many of these tags require rigid attachment to animals, which normally requires catching and r...

Background Motion detecting archival data loggers such as accelerometers have become increasingly important in animal biotelemetry and offer unique insights into animal behavior, energetics, and kinematics. However, challenges remain for successful deployment and interpretation of data from captive and wild animals. Accelerometer sensors require be...

Quantifying fine-scale locomotor behaviours associated with different activities is challenging for free-swimming fish. Biologging and biotelemetry tools can help address this problem. An open channel flume was used to generate volitional swimming speed (Us) estimates of cultured lake sturgeon (Acipenser fulvescens Rafinesque, 1817) and these were...

Cross-flows (winds or currents) affect animal movements [ 1–3 ]. Animals can temporarily be carried off course or permanently carried away from their preferred habitat by drift depending on their own traveling speed in relation to that of the flow [ 1 ]. Animals able to only weakly fly or swim will be the most impacted (e.g., [ 4 ]). To circumvent...

Major transitions between marine and freshwater habitats are relatively infrequent, primarily as a result of major physiological and ecological challenges. Few species of cartilaginous fish have evolved to occupy freshwater habitats. Current thought suggests that the metabolic physiology of sharks has remained a barrier to the diversification of th...

A spring emergence of avian haemosporidian infections is nearly universal among temperate zone birds and is often described as a cost of reproductive effort. We take advantage of the opportunistic (i.e., aseasonal) breeding schedule of the red crossbill (Loxia curvirostra) to determine the relative contributions of season vs. host physiology to the...

Activity patterns of animals often relate to environmental variables such as food availability and predation pressure. Technological advances are providing us with new tools to monitor and better understand these activity patterns. We used animal-attached data loggers recording acceleration and depth to compare activity patterns and vertical habita...

1. Maintaining a high and stable body temperature is often critical for female ectotherms during reproduction. Yet this strategy may be energetically costly, and therefore challenging, during this period of already high-energy demand. 2. Here, the 6-week deployment of tri-axial accelerometers (n = 6) on a marine ectotherm, the loggerhead turtle (C...

Dynamic body acceleration (DBA) has been used as a proxy for energy expenditure in logger-equipped animals, with researchers summing the acceleration (overall dynamic body acceleration--ODBA) from the three orthogonal axes of devices. The vector of the dynamic body acceleration (VeDBA) may be a better proxy so this study compared ODBA and VeDBA as...

Over-fishing may lead to a decrease in fish abundance and a proliferation of jellyfish. Active movements and prey search might be thought to provide a competitive advantage for fish, but here we use data-loggers to show that the frequently occurring coastal jellyfish (Rhizostoma octopus) does not simply passively drift to encounter prey. Jellyfish...

Optimal foraging models predict that large predators should concentrate on large prey in order to maximize their net gain of energy intake. Here, we show that the largest species of sea turtle, Dermochelys coriacea, does not strictly adhere to this general pattern. Field observations combined with a theoretical model suggest that a 300 kg leatherba...