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The time that animals spend travelling at various speeds and the tortuosity of their movement paths are two of the many things that affect space-use by animals. In this, high turn rates are predicted to be energetically costly, especially at high travel speeds, which implies that animals should modulate their speed according to path characteristics. When animals move so as to maximize distance and minimize metabolic energy expenditure, they travel most efficiently at the speed that gives them a minimum cost of transport (COTmin), a well-defined point for animals that move entirely in fluid media. Theoretical considerations show though, that land animals should travel at their maximum speed to minimize COT, which they do not, instead travelling at walking pace. So, to what extent does COTmin depend on speed and turn rate and how might this relate to movement paths? We measured oxygen consumption in humans walking along paths with varied tortuosity at defined speeds to demonstrate that the energetic costs of negotiating these paths increase disproportionately with both speed and angular velocity. This resulted in the COTmin occurring at very low speeds, and these COTmin speeds reduced with increased path tortuosity and angular velocity. Logged movement data from six free-ranging terrestrial species underpinned this because all individuals turned with greater angular velocity the slower their travel speeds across their full speed range. It seems, therefore, that land animals may strive to achieve minimum movement costs by reducing speed with increasing path variability, providing one of many possible explanations as to why speed is much lower than currently predicted based on lab measurements of mammalian locomotor performance.

Animals alter their habitat use in response to the energetic demands of movement ('energy landscapes') and the risk of predation ('the landscape of fear'). Recent research suggests that animals also select habitats and move in ways that minimise their chance of temporarily losing control of movement and thereby suffering slips, falls, collisions or other accidents, particularly when the consequences are likely to be severe (resulting in injury or death). We propose that animals respond to the costs of an 'accident landscape' in conjunction with predation risk and energetic costs when deciding when, where, and how to move in their daily lives. We develop a novel theoretical framework describing how features of physical landscapes interact with animal size, morphology, and behaviour to affect the risk and severity of accidents, and predict how accident risk might interact with predation risk and energetic costs to dictate movement decisions across the physical landscape. Future research should focus on testing the hypotheses presented here for different real-world systems to gain insight into the relative importance of theorised effects in the field.

Sloths are notoriously slow and consequently have limited dispersal ability, which makes them particularly vulnerable to the effects of habitat fragmentation and degradation. Sloths in Costa Rica are considered of conservation concern due to habitat loss, livestock production and increasing urbanization. Reintroductions from rescue centres are commonplace across the country, yet their genetic diversity and population structure are unknown, and there is currently little consideration of the genetic background prior to intervention or releases. We used microsatellite analysis to undertake the first exploratory investigation into sloth population genetics in Costa Rica. Using data from 98 two‐fingered sloths (Choloepus hoffmanni) from four different geographic regions, we determined the presence of four potential genetic groups, three of them with minimal population structuring despite the limited dispersal ability and presence of physical barriers. Sloths from the North appear to represent a highly distinct population that we propose may require management as a discrete unit for conservation. We stress the need for additional analyses to better understand the genetic structure and diversity of North andWest regions and suggest that rescue facilities in Costa Rica should consider the genetic background of rehabilitated sloths when planning future reintroductions. Our results also highlight the threat posed by physical isolation due to widespread urbanization and agriculture expansion for a species with a weak dispersal ability.

Animal behavior is elicited, in part, in response to external conditions, but understanding how animals perceive the environment and make the decisions that bring about these behavioral responses is challenging.Animal heads often move during specific behaviors and, additionally, typically have sensory systems (notably vision, smell, and hearing) sampling in defined arcs (normally to the front of their heads). As such, head‐mounted electronic sensors consisting of accelerometers and magnetometers, which can be used to determine the movement and directionality of animal heads (where head “movement” is defined here as changes in heading [azimuth] and/or pitch [elevation angle]), can potentially provide information both on behaviors in general and also clarify which parts of the environment the animals might be prioritizing (“environmental framing”).We propose a new approach to visualize the data of such head‐mounted tags that combines the instantaneous outputs of head heading and pitch in a single intuitive spherical plot. This sphere has magnetic heading denoted by “longitude” position and head pitch by “latitude” on this “orientation sphere” (O‐sphere).We construct the O‐sphere for the head rotations of a number of vertebrates with contrasting body shape and ecology (oryx, sheep, tortoises, and turtles), illustrating various behaviors, including foraging, walking, and environmental scanning. We also propose correcting head orientations for body orientations to highlight specific heading‐independent head rotation, and propose the derivation of O‐sphere‐metrics, such as angular speed across the sphere. This should help identify the functions of various head behaviors.Visualizations of the O‐sphere provide an intuitive representation of animal behavior manifest via head orientation and rotation. This has ramifications for quantifying and understanding behaviors ranging from navigation through vigilance to feeding and, when used in tandem with body movement, should provide an important link between perception of the environment and response to it in free‐ranging animals., We provide a new visualization of animal body and head orientation that shows in an intuitive manner how the animal frames the environment. Metrics derived from this should help us understand how animals make decisions to adopt particular behaviours.

We understand little about the energetic costs of flight in free-ranging birds; in part since current techniques for estimating flight energetics in the wild are limited. Accelerometry is known to estimate energy expenditure through body movement in terrestrial animals, once calibrated using a treadmill with chamber respirometry. The flight equivalent, a wind tunnel with mask respirometry, is particularly difficult to instigate, and has not been applied to calibrate accelerometry. We take the first steps in exploring a novel method for calibrating accelerometers with flight energy expenditure. We collected accelerometry data for Harris’s Hawks Parabuteo unicinctus flying to varying heights up to 4.1 m over a small horizontal distance; the mechanical energy expended to gain height can be estimated from physical first principles. The relationship between accelerometry and mechanical energy expenditure was strong, and while a simple wing flapping model confirmed that accelerometry is sensitive to both changes in wing beat amplitude and frequency, the relationship was explained predominately by changes in wing beat frequency, and less so by changes in amplitude. Our study provides initial, positive evidence that accelerometry can be calibrated with body power using climbing flights, potentially providing a basis for estimating flapping flight metabolic rate at least in situations of altitude gain.

International audience; Decomposing the life track of an animal into behavioral segments is a fundamental challenge for movement ecology. The proliferation of high‐resolution data, often collected many times per second, offers much opportunity for understanding animal movement. However, the sheer size of modern data sets means there is an increasing need for rapid, novel computational techniques to make sense of these data. Most existing methods were designed with smaller data sets in mind and can thus be prohibitively slow. Here, we introduce a method for segmenting high‐resolution movement trajectories into sites of interest and transitions between these sites. This builds on a previous algorithm of Benhamou and Riotte‐Lambert (2012). Adapting it for use with high‐resolution data. The data’s resolution removed the need to interpolate between successive locations, allowing us to increase the algorithm’s speed by approximately two orders of magnitude with essentially no drop in accuracy. Furthermore, we incorporate a color scheme for testing the level of confidence in the algorithm's inference (high = green, medium = amber, low = red). We demonstrate the speed and accuracy of our algorithm with application to both simulated and real data (Alpine cattle at 1 Hz resolution). On simulated data, our algorithm correctly identified the sites of interest for 99% of “high confidence” paths. For the cattle data, the algorithm identified the two known sites of interest: a watering hole and a milking station. It also identified several other sites which can be related to hypothesized environmental drivers (e.g., food). Our algorithm gives an efficient method for turning a long, high‐resolution movement path into a schematic representation of broadscale decisions, allowing a direct link to existing point‐to‐point analysis techniques such as optimal foraging theory. It is encoded into an R package called SitesInterest, so should serve as a valuable tool for making sense of these increasingly large data streams.

The amount of energy an animal uses to move may constitute a significant fraction of its energy budget, so detailed descriptions of wild animal activity budgets can help to understand the ecology of a species, both at the individual and at the population levels. The rocky‐reef fishes inhabiting the northern Patagonian gulfs of Argentina are important economic and recreational resources for which no activity or energy budgets are available. This fish assemblage may reach high aggregated biomasses (exceeding several hundreds of kilogrammes of fish distributed along a few hundred metres of linear reef ledges) and is not clear how such biomasses can be supported by the low productivity of the Patagonian coastal waters. We used animal‐attached accelerometers to characterise the behaviours and activity budgets for the most abundant and ubiquitous species of this assemblage, the Argentine sea bass or ‘Mero’ Acanthistius patachonicus (Jenyns, 1840; Osteichthyes: Serranidae). Sixteen individuals were tagged (two in captivity and 14 free‐living) and an ethogram was generated from acceleration recordings in varying environmental conditions. Two algorithms were used to classify the behaviours of wild fish. Both showed generally similar results during the cold‐water season (8–10°C), but differed slightly in the warm‐water season (16–18°C). Overall, sea bass were more active during warm season (mean time spent engaged in active behaviours; 46%, range; 24–60%). In contrast, during cold season fish only spent a mean of 29% of their time in active behaviours (range; 15–49%). No clear response to tidal state or ambient light was found, but some fish were more active during the night in the cold water season. Here, we provide the first activity budgets for the conspicuous Argentine sea bass, which contribute to our understanding of rocky‐reef fish behaviour in Patagonia. Fil: Beltramino, Lucas Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina Fil: Venerus, Leonardo Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina Fil: Trobbiani, Gastón Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina Fil: Wilson, Rory P.. Swansea University; Reino Unido Fil: Ciancio Blanc, Javier Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina

1. Step selection analysis (SSA) is a fundamental technique for uncovering the drivers of animal movement decisions. Its typical use has been to view an animal as ‘selecting’ each measured location, given its current (and possibly previous) locations. Although an animal is unlikely to make decisions precisely at the times its locations are measured, if data are gathered at a relatively low frequency (every few minutes or hours) this is often the best that can be done. Nowadays, though, tracking data are increasingly gathered at very high frequencies, often ≥1 Hz, so it may be possible to exploit these data to perform more behaviourally‐meaningful step selection analysis.\ud \ud 2. Here, we present a technique to do this. We first use an existing algorithm to determine the turning‐points in an animal's movement path. We define a ‘step’ to be a straight‐line movement between successive turning‐points. We then construct a generalised version of integrated SSA (iSSA), called time‐varying iSSA (tiSSA), which deals with the fact that turning‐points are usually irregularly spaced in time. We demonstrate the efficacy of tiSSA by application to data on both simulated animals and free‐ranging goats Capra aegagrus hircus, comparing our results to those of regular iSSA with locations that are separated by a constant time‐interval.\ud \ud 3. Using (regular) iSSA with constant time‐steps can give results that are misleading compared to using tiSSA with the actual turns made by the animals. Furthermore, tiSSA can be used to infer covariates that are dependent on the time between turns, which is not possible with regular iSSA. As an example, we show that our study animals tend to spend less time between successive turns when the ground is rockier and/or the temperature is hotter.\ud \ud 4. By constructing a step selection technique that works between observed turning‐points of animals, we enable step selection to be used on high‐frequency movement data, which are becoming increasingly prevalent in modern biologging studies. Furthermore, since turning‐points can be viewed as decisions, our method places step selection analysis on a more behaviourally‐meaningful footing compared to previous techniques.

1. Recent advances in biologging have resulted in animal location data at unprecedentedly high temporal resolutions, sometimes many times per second. However, many current methods for analysing animal movement (e.g. step selection analysis or state-space modelling) were developed with lower-resolution data in mind. To make such methods usable with high-resolution data, we require techniques to identify features within the trajectory where movement deviates from a straight line. 2. We propose that the intricacies of movement paths, and particularly turns, reflect decisions made by animals so that turn points are particularly relevant for behavioural ecologists. As such, we introduce a fast, accurate algorithm for inferring turning-points in high-resolution data. For analysing big data, speed and scalability are vitally important. We test our algorithm on simulated data, where varying amounts of noise were added to paths of straight-line segments interspersed with turns. We also demonstrate our algorithm on data of free-ranging oryx (Oryx leucoryx). We compare our algorithm to existing statistical techniques for break-point inference. 3. The algorithm scales linearly and can analyse several hundred-thousand data-points in a few seconds on a mid-range desktop computer. It identified turnpoints in simulated data with complete accuracy when the noise in the headings had a standard deviation of 8 degrees, well within the tolerance of many modern biologgers. It has comparable accuracy to the existing algorithms tested, and is up to three orders of magnitude faster. 4. Our algorithm, freely available in R and Python, serves as an initial step in processing ultra high-resolution animal movement data, resulting in a rarefied path that can be used as an input into many existing step-and-turn methods of analysis. The resulting path consists of points where the animal makes a clear turn, and thereby provides valuable data on decisions underlying movement patterns. As such, it provides an important breakthrough required as a starting point for analysing sub-second resolution data.

The recreational use of various stimulant drugs has been implicated in the development of movement disorders through dysregulation of the dopaminergic and serotoninergic neurotransmitter systems. The present study investigated psychomotor differences in current and former recreational stimulant drug users compared with nonusing controls. Sixty participants comprised 3 groups: 20 current stimulant drug users (CSUs; 11 men, aged 31.4 ± 9.1 years), 20 former stimulant drug users (FSUs; 5 men, aged 39.1 ± 8.5 years), and 20 nonuser controls (NUCs; 5 men, aged 35.7 ± 6.4 years). Psychomotor arm steadiness for each participant was assessed with a wrist-attached accelerometer during 5 arm positions with eyes open and then eyes closed. Arm-drop of arm position was indicated by the arm longitudinal rotation axis (ALoRA), and tremor was indicated by the overall vector of dynamic body acceleration (VeDBA). Overall, CSUs performed the most poorly on ALoRA (P < .05) and VeDBA indices (P < .05), and FSUs perform almost as poorly on VeDBA indices (P < .05) compared with NUCs. It was concluded that stimulant drug use, primarily MDMA and amphetamines, may result in acute stimulant-induced tremor as well as long-term proprioceptive deficits in terms of arm-droop.

Assessment of animal internal “state” – which includes hormonal, disease, nutritional, and emotional states – is normally considered the province of laboratory work, since its determination in animals in the wild is considered more difficult. However, we show that accelerometers attached externally to animals as diverse as elephants, cockroaches, and humans display consistent signal differences in micro-movement that are indicative of internal state. Originally used to elucidate the behavior of wild animals, accelerometers also have great potential for highlighting animal actions, which are considered as responses stemming from the interplay between internal state and external environment. Advances in accelerometry may help wildlife managers understand how internal state is linked to behavior and movement, and thus clarify issues ranging from how animals cope with the presence of newly constructed roads to how diseased animals might change movement patterns and therefore modulate disease spread.

Energy costs during breeding play an important role in the evolution of life history traits. Seabirds show substantial variation in both incubation shift length (ISL) and metabolic rates. However, it is still unclear how variation in life history traits relates to incubation metabolic rates (IMR). Here, we examine the relationship between IMR and life history traits, including ISL, fledging strategy (precocial to altricial), incubation period, nest location (surface vs. underground) and clutch mass relative to adult body mass for 30 species of seabirds collated from the literature. Using both conventional non-phylogenetic and phylogenetic generalized least-squares approaches, we show that IMR is negatively associated with ISL, relative clutch mass and with underground nesting, while fledging strategy and incubation period have no impact on IMR once phylogeny is accounted for. Maximum likelihood reconstructions further suggest than ancestral seabirds had average ISL and relative clutch mass, and were surface nesters. We conclude that lower metabolic rates during incubation are associated with both an increased incubation shift length that allows animals to travel farther, as well as the evolutionary emergence of underground nesting that requires less social interaction.

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 investigated the power requirements (using dynamic body acceleration as proxy for power) in relation to movement geometry of nine whale sharks (Rhincodon typus) and discovered that movement geometry significantly affects power requirements in a manner similar to travel speed. 3. Whale sharks dive repeatedly and use their negative buoyancy to glide during descents, while ascents were characterized by strong locomotory activity. Power requirements of ascents increased with the square of degrees pitch and were significantly greater than both level and descent swimming. 4. The differences in geometry of five dive types are explored using four empirical optimality models based on minimum power based on our measurements. These models suggest that some dive types minimize the horizontal cost of transport, whereas others minimize the cost of vertical transport. Whale sharks are presumed to shift diving geometry with changing currencies and ecological context. The adaptive significance of appropriate diving geometry and associated power requirements is discussed with regard to current hypotheses for diving in gill-breathers: search, orientation and travel. 5. Movement geometry significantly affects the cost of locomotion and is probably modulated by animals according to ecological circumstance. The in situ measurement of animal trajectory and locomotory activity via accelerometers now permits testing context-dependent movement geometry in free-ranging animals.

Summary 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 measurements of overall dynamic body acceleration (ODBA) through the attachment of miniature acceleration data-loggers. This technique is easy to implement and has the promise to be able to resolve energy expenditure with fine (sub-second) temporal resolution, making it the only method which promises to able to determine the cost of short-lived behaviours. Increasing evidence supports the validity of the approach although the rationale behind it is vague. 3. This study explores link between metabolic energy and acceleration by examining what is known about how muscular tissue converts metabolic energy to mechanical work via muscular contraction and how Newtonian physics facilitates a derivation of Power (the rate at which work is performed) from acceleration. The link between metabolic energy and acceleration appears to involve three discrete processes: (i) the ratio of mechanical work to metabolic work performed by a single muscle (mechano-chemical efficiency); (ii) the ratio of external and internal work performed (mechanical work of the limbs in relation to that of the centre of mass); and (iii) the ratio of inertial to de novo mechanical work. These processes may vary according to the animal’s mass, the medium in which it travels and its gait or behaviour. 4. Assessment of movement has limited application in defining non-movement energy expenditure such as that involved in specific dynamic action or non-shivering thermogenesis. However, this non-movement energy expenditure may often be modelled with reasonable confidence. The utility and appropriateness of the ODBA-energy expenditure method depends on a set of conditions, which we define and suggest should be assessed a priori. 5. This study explores the framework behind the ODBA-energy expenditure method to enable informed decisions to be made regarding the suitability for specific research questions addressed, as well as highlighting calibration needs.

This research is a contribution to the CAASE project funded by King Abdullah University of Science and Technology (KAUST) under the KAUST Sensor Initiative. We thank the staff and leadership of the Oceanografic in Valencia for their help and support during the sensor tests with turtles and crabs.

Diving synchrony was examined for varying group sizes of African penguins (Spheniscus demersus) travelling to their foraging grounds from their breeding islands. Groups of fewer than 12 birds always dived synchronously, whereas groups of more than 17 birds always dived asynchronously. Since travelling penguins do not dive deeply, large groups of birds can remain together irrespective of diving synchronization. Observations from boats showed that foraging penguins rarely occurred in groups of more than 17 birds. We suggest that groups of penguins that do not have synchronized dives cannot forage effectively, because foraging penguins dive deeply.

Summary 1. Species potentially competing for the same resource are considered to be able to co-exist if they occupy different niches. In an apparent example of this, Adelie, Chinstrap and Gentoo penguins all feed predominantly on krill Euphausea superba at certain sites of sympatry in Antarctica and are proposed to exploit different niche hyper-volumes via differential area and depth utilization. 2. Patterns of foraging for 49 of these penguins breeding in sympatry were assessed using dead-reckoning loggers to examine foraging niche overlap. 3. Area use overlaps were 0·29 for Adelie ∩ Chinstrap, 0·44 for Adelie ∩ Gentoo, and 0·40 for Chinstrap ∩ Adelie and depth use overlaps were 0·69 for Adelie ∩ Chinstrap, 0·48 for Adelie ∩ Gentoo, and 0·52 for Chinstrap ∩ Gentoo Penguins. 4. Foraging efficiency was greatest for Adelie Penguins diving near surface waters (0–15 m) while Chinstraps were most efficient at medium depths (15–60 m) and Gentoo Penguins most efficient at deeper depths (> 60 m). There appear to be physiological reasons for this. Penguins primarily exploited those depths where they were most efficient. 5. The overlap for foraging periods was 0·47 for Adelie ∩ Chinstrap, 0·26 for Adelie ∩ Gentoo, and 0·40 for Chinstrap ∩ Gentoo Penguins. Chinstraps foraged primarily at night, Gentoos during the morning and Adelies in the afternoon. Temporal differences in foraging may result in the three species exploiting krill at those depths where it is best adapted to pursue it, this being mediated by the diel vertical migration of krill. 6. Integration of all measured parameters together gives minimal overlap between species with total overlaps of 0·09 for Adelie ∩ Chinstrap, 0·05 for Adelie ∩ Gentoo, and 0·08 for Chinstrap ∩ Gentoo Penguins so it appears that these penguins conform to conventional theory in avoiding competition in areas of sympatry. However, a model incorporating prey movement between hyper-volumes indicates that penguins may still compete, even in the virtual absence of hyper-volume overlap. 7. This study shows that Pygoscelid penguin do indeed exploit different hypervolumes in areas of sympatry but that such exploitation of different niches by sympatric species feeding on a common resource does not necessarily result in reduced competition if the mobility of prey is high.

A new area of biological research is identifying and grouping patterns of behaviour in wild animals by analysing data obtained through the attachment of tri-axial accelerometers. As these recording devices become smaller and less expensive their use has increased. Currently acceleration data are visualised as 2D time series plots, and analyses are based on summary statistics and the application of Fourier transforms. We develop alternate visualisations of this data so as to analyse, explore and present new patterns of animal behaviour. Our visualisations include interactive spherical scatterplots, spherical histograms, clustering methods, and feature-based state diagrams of the data. We study the application of these visualisation methods to accelerometry data from animal movement. The reaction of biologists to these visualisations is also reported.

Radiotelemetry was used to assess the distribution and diving behaviour of Rock Shags Phalacrocorax magellanicus and Red-legged Cormorants Phalacrocorax gaimardi breeding in sympatry, and Rock Shags breeding in isolation. When breeding in sympatry there was little overlap in the foraging locations of the two species, with the highest densities of each species separated by 10 km. Red-legged Cormorants fed significantly closer to the breeding colony than did Rock Shags and undertook shorter foraging trips, making almost twice as many foraging trips per day as Rock Shags. Rock Shags breeding in isolation had a shorter foraging range than the birds breeding in sympatry with Red-legged Cormorants and foraging trip duration was significantly shorter. However, the number of feeding trips per day was similar between areas of sympatry and allopatry. Differences in the foraging ecology of Rock Shags in areas of sympatry and allopatry may be due to interspecific competition, which forces niche differentiation. The distance between foraging sites, the speed of movement of the prey, a species tendency to move into prey-depleted areas and the length of the breeding season [during which the birds are constrained to be in the same area) may play critical roles in determining the extent to which differential area use by competitors is a strategy that benefits both parties.

1. Time and energy are key currencies in animal ecology, and judicious management of these is a primary focus for natural selection. At present, however, there are only two main methods for estimation of rate of energy expenditure in the field, heart rate and doubly labelled water, both of which have been used with success; but both also have their limitations. 2. The deployment of data loggers that measure acceleration is emerging as a powerful tool for quantifying the behaviour of free-living animals. Given that animal movement requires the use of energy, the accelerometry technique potentially has application in the quantification of rate of energy expenditure during activity. 3. In the present study, we test the hypothesis that acceleration can serve as a proxy for rate of energy expenditure in free-living animals. We measured rate of energy expenditure as rates of O2 consumption (VO2) and CO2 production (VCO2) in great cormorants (Phalacrocorax carbo) at rest and during pedestrian exercise. VO2 and VCO2 were then related to overall dynamic body acceleration (ODBA) measured with an externally attached three-axis accelerometer. 4. Both VO2 and VCO2 were significantly positively associated with ODBA in great cormorants. This suggests that accelerometric measurements of ODBA can be used to estimate VO2 and VCO2 and, with some additional assumptions regarding metabolic substrate use and the energy equivalence of O2 and CO2, that ODBA can be used to estimate the activity specific rate of energy expenditure of free-living cormorants. 5. To verify that the approach identifies expected trends in from situations with variable power requirements, we measured ODBA in free-living imperial cormorants (Phalacrocorax atriceps) during foraging trips. We compared ODBA during return and outward foraging flights, when birds are expected to be laden and not laden with captured fish, respectively. We also examined changes in ODBA during the descent phase of diving, when power requirements are predicted to decrease with depth due to changes in buoyancy associated with compression of plumage and respiratory air. 6. In free-living imperial cormorants, ODBA, and hence estimated VO2, was higher during the return flight of a foraging bout, and decreased with depth during the descent phase of a dive, supporting the use of accelerometry for the determination of activity-specific rate of energy expenditure.

In a world that is increasingly perturbed by humans, the need to understand ecosystems is urgent. Attaching measuring devices to wild animals is often the only way to acquire vital life-history information on larger, charismatic species, and on cryptic species that do not lend themselves to observation. However, the ethics of acceptable practice for attached devices are poorly defined. Here, we consider the need for further research and attempt to identify a system that allows animal restraint practices and device-induced effects to be quantified and monitored, so that ethics committees can have a defined scale on which to base decisions.

Animal-attached remote sensing, or bio-logging, refers to the deployment of autonomous recording tags on free-living animals, so that multiple variables can be monitored at rates of many times per second, thereby generating millions of data points over periods ranging from hours to years. Rapid advances in technology are allowing scientists to use data-recording units to acquire huge, quantitative datasets of behavior from animals moving freely in their natural environment. In other words, scientists can examine wild animals in the field, behaving normally, with the same rigor that is normally used in the laboratory. The flexibility of such recording systems means that bio-logging science operates at the interface of several biological disciplines, looking at a wide array of aquatic, airborne, and terrestrial species, monitoring not only the physical characteristics of the environment, but also the animal's reactions to it. This approach is critically important in an era when global change threatens the survival of species and where habitat loss is leading to widespread extinctions.

Movements of animals provisioning offspring by central place foraging extend from short, highly local trips where food is brought back essentially unchanged from its normal condition to extensive interseasonal movement where the offspring are nourished from body reserves built up during the adult's absence from the breeding site. Here, appropriate strategies for maximizing lifetime reproductive success depend on the abundance and location of prey in relation to breeding sites and the energetics and speed of travel of the animal. Magellanic Penguins Spheniscus magellanicus undertake central place movements that are particularly variable during the incubation period; trips may last from a single day to over three weeks depending on colony locality. We reasoned that site-specific variability in prey distribution and abundance is responsible for this. Remote-sensing systems attached to 92 penguins from six different colonies over the species distributional range over the Patagonian Shelf were used to determine space use and foraging patterns in an attempt to understand the observed patterns. Birds in the north and south of the latitudinal range were essentially monophagic, feeding primarily on anchovies Engraulis anchoita and sprats Sprattus fuegensis, respectively, both species that are to be found relatively close to the colonies. Penguins in the center of the distributional range, where these pelagic school fish prey are essentially absent at that time of the year, traveled either north or south, to the same regions utilized by their conspecifics, presumably to exploit the same prey. A simple model is used to clarify patterns and can be used to predict which movement strategy is likely to be best according to colony location. During chick rearing, southerly movement of anchovies and northerly movement of sprats mean that Magellanic Penguins in the center of the distributional range may benefit, although the abundance of these fish is considered to be less than that closer to the Magellanic Penguin range limits. The extensive time involved in the foraging trips during incubation coupled with the postulated poorer prey conditions during the chick-rearing phase may help explain why Magellanic Penguin colony sizes in the center of the range are not elevated.

Detailed studies of the behavior and location of free-ranging animals can be considerably enhanced with the use of animal-mounted devices. A few devices, such as data loggers, have to be recovered to access the data, whereas satellite tags or radiocollars often are left on the animal after the study period. Recovery of devices, which usually necessitates animal recapture, can be problematic, especially in larger species. This paper presents a new, non-electronic release mechanism, requiring no power source on the animal, that was successfully tested on South American sea lions (Otaria flavescens) in Argentina during the 2003–2004 austral summer. The system has potential for many larger terrestrial or aquatic animals.

The great cormorant Phalacrocorax carbo is thought to have a wettable plumage, providing low body insulation during foraging. Great cormorants should thus be constrained by water temperatures, and show high energy requirements. Surprisingly, this species has one of the widest breeding distributions of all diving birds, and does not require more food than these other species. We explored this apparent paradox by comparing the insulative properties of body plumage in four subspecies of great cormorants ranging from tropical to polar regions. We found that all subspecies retained an insulating air layer in their plumage, which was, however, much thinner than for other species of diving birds. Detailed examination of the plumage showed that each cormorant body feather has a loose, instantaneously wet, outer section and a highly waterproof central portion. This indicates that the plumage of great cormorants is only partly wettable, and that birds maintain a thin layer of air in their plumage. Our findings suggest an unusual morphological-functional adaptation to diving which balances the antagonist constraints of thermoregulation and buoyancy.

published

Wandering Albatrosses Diomedea exulans are frequently killed when they attempt to scavenge baited hooks deployed by long-line fishing vessels. We studied the foraging ecology of Wandering Albatrosses breeding on Marion Island in order to assess the scale of interactions with known long-line fishing fleets. During incubation and late chick-rearing, birds foraged further away from the island, in warmer waters, and showed high spatial overlap with areas of intense tuna Thunnus spp. long-line fishing. During early chick-rearing, birds made shorter foraging trips and showed higher spatial overlap with the local Patagonian Toothfish Dissostichus eleginoides long-line fishery. Tracks of birds returning with offal from the Toothfish fishery showed a strong association with positions at which Toothfish long-lines were set and most diet samples taken during this stage contained fishery-related items. Independent of these seasonal differences, females foraged further from the islands and in warmer waters than males. Consequently, female distribution overlapped more with tuna long-line fisheries, whereas males interacted more with the Toothfish long-line fishery. These factors could lead to differences in the survival probabilities of males and females. Non-breeding birds foraged in warmer waters and showed the highest spatial overlap with tuna long-line fishing areas. The foraging distribution of Marion Island birds showed most spatial overlap with birds from the neighbouring Crozet Islands during the late chick-rearing and non-breeding periods. These areas of foraging overlap also coincided with areas of intense tuna long-line fishing south of Africa. As the population trends of Wandering Albatrosses at these two localities are very similar, it is possible that incidental mortality during the periods when these two populations show the highest spatial overlap could be driving these trends.

Summary 1 The published literature on the effects of flipper-bands on penguin ecology is reviewed. Six published studies show the following. 2 In Adelie Penguins Pygoscelis adeliae, flipper-bands directly damaged flippers, increased swimming costs by 24%, decreased survival in the first year after banding by 28%, and may have accelerated decline of a dwindling colony by 3%. 3 Adult return rates to colonies among flipper-banded Adelie, Chinstrap P. antarctica and Gentoo P. papua Penguins decreased by 8%, 12% and 25%, respectively, between single- and double-banded penguins. Juvenile return rates among Gentoo Penguins were reduced by 10·5%. Return rates to the colony among double-banded King Penguins Aptenodytes patagonicus were 31·3% and 6·7% lower than among single-banded birds in the first and second years after banding, respectively, and single flipper-banded birds showed annual survival rates 21·1% lower than those of birds fitted with subcutaneous transponders. 4 Among Royal Penguins Eudyptes schlegeli, there were no differences between chick growth, adult over-winter survival and fledging success between flipper-banded birds and birds fitted with transponders. 5 Adelie Penguin adult annual survival rates were lower among flipper-banded birds than among unbanded birds. 6 On the basis of dive profiles for Adelie Penguins, it is estimated that increased swimming costs of 5% reduce prey contact time by 10%, and of 24% reduce prey contact time by 48%. These estimated ‘knock-on’ or cumulative costs coupled with the survival and breeding costs shown by the majority of published field studies suggest that data collected on some flipper-banded populations are biased. 7The advantages and disadvantages of an alternative long-term marking technique, subcutaneously implanted passively interrogated transponder tags, are discussed. Research projects currently testing transponders and flipper-bands worldwide are listed.

Although they can provide valuable information on at-sea ecology, data-loggers may adversely affect energetics, diving performance, and breeding success of equipped birds. With the aim of determining the effects of leg-attached data-loggers on the activity budgets of Humboldt penguins (Spheniscus humboldti) while on land, we equipped birds kept at the Landau Zoo, Landau, Germany, with such devices. We followed them during sample periods and recorded the occurrence and length of behaviors. Birds quickly habituated to the devices within 1 day of deployment, and mean rates of device-pecking were low (0.7–1.7 pecks/hr), with device-induced behaviors accounting for

The behaviour of Magellanic Penguins Spheniscus magellanicus commuting between their foraging areas and breeding areas in San Julian Bay, Argentina, was studied to examine whether tidal rip currents affected travelling patterns. Although there was no apparent relationship between departure and arrival patterns and the state of the tidal cycle, birds travelling against the current dived for longer periods and a shorter rests on the surface than birds travelling with the current. In addition, bird swimming against the current hugged the banks of tidal rivers much more closely than did birds swimming with the, thus, reducing the magnitude of the current against which they had to swim. In cases of extremely high current speeds, birds travelling upstream walked. Models regarding the energetics of movement indicate that the strategies adopted by Magellanic Penguins can result in substantial energy savings. Fil: Wilson, Rory P. Institut fur Meereskunde; Alemania Fil: Locca, R.. No especifíca; Fil: Scolaro, Jose Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina Fil: Frere, Esteban. Universidad Nacional de la Patagonia Austral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Gandini, Patricia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral; Argentina

The foraging ecology of King Penguins (Aptenodytes patagonicus) at Possession Island, Crozet Archipelago, was studied between January and March 1993 and between February and March 1994. Diving activity and position of the birds were determined via externally attached logging units. Feeding behavior was detected using stomach temperature sensors. All calculated positions of the birds occurred south of Possession Island. The area most frequented was situated 250 km south of the island (48.5° S), where birds stayed for 40 h during a foraging trip, on average. The overall swim speed differed with time into the foraging trip, being lowest during the central part and highest (10 km/h) during the last night at sea, when birds were returning to the colony. Diving activities showed a clear diurnal pattern, with maximum dive depth being dependent on ambient light levels. During the night, only shallow dives 85% of the feeding events occurred during daylight and at twilight. Mean food mass ingested was calculated to be ∼2350 g/d, with the highest amounts ingested during the central and penultimate days of the foraging trip. Foraging success (grams ingested per unit time underwater) was also highest (>370 g/h) at this time. The relationships between foraging strategy, inter‐ and intraspecific competition, and King Penguin body mass are discussed.

mounds on a Texas coastal prairie. Oecologia (Berlin) 66: 111-115. Sprugel, D. G. 1976. Dynamic structure of wave-regenerated Aibes balsamea forests in the north-eastern United States. Journal of Ecology 64:889-909. Swihart, R. K., and P. M. Picone. 1991. Effects ofwoodchuck activity on woody plants near burrows. Journal of Mammalogy 72:607-611. Wildung, R. E., T. R. Garland, nd R. L. Buchbom. 1975. The interdependent effects of soil temperature and water content on soil respiration rate and plant root decompo? sition in arid grassland soils. Soil Biology and Biochemistry 7:373-378.

THE recent articles on the effects of telemetry equipment fitted to free-living wild birds (Dixon 2011, Peniche and others 2011) have highlighted an issue that has long been a concern of the RSPCA. While the RSPCA recognises that the use of such devices is important to gain a better understanding of the behaviour and movements of free-living wildlife and, indeed, uses such …

Rates of CO2 production by breeding Jackass Penguins (mean mass, 3170 g) were measured by using doubly labeled water. Time budgets were estimated from behavioral observations, and energy budgets were calculated for a typical 2-d period of 24 h sitting on a nest and 24 h off the nest (which includes 9 h foraging at sea). Distances traveled at sea were determined by using speed/ time meters harnessed to five birds containing doubly labeled water, and these measurements were used to calculate the energetic costs of swimming. Field metabolic rates (as CO2 production) averaged 0.991 mL'g'l h-', or (in energy units) 3890 kJ penguin-1 2 d-'. Energy expenditures were 1.7 times the standard metabolic rate (SMR) while brooding, 6.6 x SMR while foraging, 9.8 x SMR while swimming underwater, and 2.6 x SMR integrated over a 2-d period. Penguins spent z48% of their energy budget and 19% of their time budget to obtain food. Foraging efficiency (the metabolizable energy gained while foraging . the energy used during foraging) was 2.1 for birds with small chicks. Fresh mass consumption rates calculated on the basis of the chemical composition of Cape anchovy, Engraulis capensis, were Z758 g pen- guin-l 2 d-' for adults brooding small chicks, and 76 kg of anchovy per nest (2 adults, 2 chicks) over a 70-d nestling period. An adult penguin would need to capture ; 138 kg of fish per year. The 160,000 penguins using the South African fishing grounds would consume about 2.21 x 107 kg of fish per year, of which z80% or 1.77 x 107 kg would be Cape anchovies. This is z8% of the average commercial anchovy catch in that area.

Observations of foraging patterns are essential to understanding the energetic ecology of marine animals. However, direct observations are not often feasible in the field because most foraging takes place below the sea surface or at great distances from land. Attachment of data-recording devices to animals can greatly facilitate the collecton of meaningful data. Devices are being used to an increasing extent on marine mammals (Kooyman et al. 1976, Ray et al. 1978), birds (Kooyman et al. 1971, 1982, Adams and Brown 1983, Lishman and Croxall 1983, Wilson and Bain 1984a, b), reptiles (Stoneburner 1982), and fish (Voegeli and Piucock 1980, Priede 1983a). These devices may supply data upon recovery (e.g., Kooyman et al. 1971, 1982) or through telemetry to local receivers (e.g., Voegeli and Piucock 1980, Priede 1983a, b) or to orbiting satellites (Stoneburner 1982). The effects of instrument mass and harness attachment on land animals are considered to have the potential of affecting the outcomes of experiments and observations (Dumke and Pils 1973, Gilmeretal. 1974, Perry 1981, Perryetal. 1981). However, the effects of devices on marine animals, which live in a much more viscous medium than air, have not been evaluated. In this study we investigated the effects of attached instruments on the foraging activity of the African Penguin (Spheniscus demersus). We show that instrument size may adversely affect foraging behavior, but that data obtained using devices of varying sizes can be used to back-calculate true foraging parameters of free-swimming penguins without devices. Data-recording devices are especially important in studies of free-swimming penguins because these birds are inconspicuous on the surface of the water and are not visible during their frequent traveling and foraging dives. Instruments have been constructed to record speed (Wilson and Bain 1 984b), foraging range (Wilson and Bain 1984b, Wilson and Achleitner 1985), dive time (Trivelpiece et al., in press), dive frequency and depth (Kooyman et al. 1982, Wilson and Bain 1984a). Results show that African Penguins are capable of sustained speeds of at least 7.5 km/h (Nagy et al. 1984) and that other penguin species forage at depths exceeding 200 m (Kooyman et al. 1982). Measurements of foraging distance have also been used to estimate the energy cost of swimming and to construct energy budgets (Nagy et al. 1984). Devices may affect performance in two ways. The mere presence of a device may modify behavior. However, in our experience with penguins this does not appear to be important; after a short period of adjustment, African Penguins with devices continued their normal nesting activity and entered the sea to forage with frequencies similar to control birds (Wilson and Bain 1984a, b). Second, the mass or drag of a device may retard swimming speed, thus reducing dive depth, foraging range, and the number of prey encountered. Instrument mass in itself probably does not adversely influence foraging behavior because attached devices are usually .05) which suggests that the smallest meters had virtually no effect on foraging behavior. On the other hand, two penguins fitted with an electronic distance meter 14.6% of penguin