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Background Quantifying metabolic rate in free-living animals is invaluable in understanding the costs of behaviour and movement for individuals and communities. Dynamic body acceleration (DBA) metrics, such as vectoral DBA (VeDBA), are commonly used as proxies for the energy expenditure of movement but are of limited applicability for slow-moving species. It has recently been suggested that metrics based on angular velocity might be better suited to characterise their energetics. We investigated whether a novel metric—the ‘Rate of change of Rotational Movement (RocRM)’, calculated from the vectoral sum of change in the pitch, roll and yaw/heading axes over a given length of time, is a suitable proxy for energy expenditure. Results We found that RocRM can be used as an alternative energy expenditure proxy in a slow-moving benthic invertebrate. Eleven Giant spider conchs Lambis truncata (collected in the Red Sea) were instrumented with multiple channel (Daily Diary) tags and kept in sealed chambers for 5 h while their oxygen consumption, V̇O2, was measured. We found RocRM to be positively correlated with V̇O2, this relationship being affected by the time-step (i.e. the range of the calculated differential) of the RocRM. Time steps of 1, 5, 10 and 60 s yielded an explained variability of between 15 and 31%. The relationship between V̇O2 and VeDBA was not statistically significant, suggesting RocRM to provide more accurate estimations of metabolic rates in L. truncata. Conclusions RocRM proved to be a statistically significant predictor of V̇O2 where VeDBA did not, validating the approach of using angular-based metrics over dynamic movement-based ones for slower moving animals. Further work is required to validate the use of RocRM for other species, particularly in animals with minimally dynamic movement, to better understand energetic costs of whole ecosystems. Unexplained variability in the models might be a consequence of the methodology used, but also likely a result of conch activity that does not manifest in movement of the shell. Additionally, density plots of mean RocRM at each time-step suggest differences in movement scales, which may collectively be useful as a species fingerprint of movement going forward.

Background The metabolic syndrome (MetS), defined by the simultaneous clustering of cardio-metabolic risk factors, is a significant worldwide public health burden with an estimated 25% prevalence worldwide. The pathogenesis of MetS is not entirely clear and the use of molecular level data could help uncover common pathogenic pathways behind the observed clustering. Methods Using a highly multiplexed aptamer-based affinity proteomics platform, we examined associations between plasma proteins and prevalent and incident MetS in the KORA cohort (n = 998) and replicated our results for prevalent MetS in the HUNT3 study (n = 923). We applied logistic regression models adjusted for age, sex, smoking status, and physical activity. We used the bootstrap ranking algorithm of least absolute shrinkage and selection operator (LASSO) to select a predictive model from the incident MetS associated proteins and used area under the curve (AUC) to assess its performance. Finally, we investigated the causal effect of the replicated proteins on MetS using two-sample Mendelian randomization. Results Prevalent MetS was associated with 116 proteins, of which 53 replicated in HUNT. These included previously reported proteins like leptin, and new proteins like NTR domain-containing protein 2 and endoplasmic reticulum protein 29. Incident MetS was associated with 14 proteins in KORA, of which 13 overlap the prevalent MetS associated proteins with soluble advanced glycosylation end product-specific receptor (sRAGE) being unique to incident MetS. The LASSO selected an eight-protein predictive model with an (AUC = 0.75; 95% CI = 0.71–0.79) in KORA. Mendelian randomization suggested causal effects of three proteins on MetS, namely apolipoprotein E2 (APOE2) (Wald-Ratio = − 0.12, Wald-p = 3.63e−13), apolipoprotein B (APOB) (Wald-Ratio = − 0.09, Wald-p = 2.54e−04) and proto-oncogene tyrosine-protein kinase receptor (RET) (Wald-Ratio = 0.10, Wald-p = 5.40e−04). Conclusions Our findings offer new insights into the plasma proteome underlying MetS and identify new protein associations. We reveal possible casual effects of APOE2, APOB and RET on MetS. Our results highlight protein candidates that could potentially serve as targets for prevention and therapy.

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.

Background Semi-aquatic mammals exploit resources both on land and in water and may require both to meet their habitat requirements including food- and building resources, refuges, and for social interactions with conspecifics. Within this, the specific availability of both terrestrial and aquatic resources is expected to impact individual fitness. Beavers are highly dependent on water for movement and protection from predators. They are central place foragers and mostly forage on woody vegetation near water although aquatic vegetation may also be an important food resource. However, little is known about their use of aquatic habitats. We aimed to address this knowledge gap by dead-reckoning fine-scale movement tracks and classifying fine-scale diving events, which we then related to the spatial distribution of aquatic vegetation and habitat components within the territory. Results Overall, there was a statistically clear decrease in probability that diving would occur at dawn and with increasing distance from territory borders. In addition, the distance from the lodge at which animals dived decreased through the night and during the spring/early summer. There was strong selection for diving habitats located closer to the riverbank, with stronger selection for these areas being observed in individuals with larger home ranges. We saw a higher selection for diving above clay sediment, and within 150 m from the lodge, presumably because mud and clay sediment tended to be located closer to the lodge than sand and rock sediment. Furthermore, we found a clear selection for diving in the presence of quillwort (Isoetes spp.), shoreweed (Littorella uniflora), and stonewort (Nitella spp.). Selection for these focal species was stronger among subordinate individuals. Individuals with lower body condition dived closer to the beaver lodge, and dives located further from the lodge were associated with high densities of aquatic vegetation. Conclusion We provide new knowledge on the aquatic habitat use in a semi-aquatic mammal and show how energetic constraints may shape how beavers spatially use the aquatic environment, whereby short and shallow dives appear most beneficial. We show how aquatic habitats may have great importance for both foraging, building materials and safety, and discuss to how they may affect the fitness of individuals.

Here we examine the association between DNA methylation in circulating leukocytes and blood lipids in a multi-ethnic sample of 16,265 subjects. We identify 148, 35, and 4 novel associations among Europeans, African Americans, and Hispanics, respectively, and an additional 186 novel associations through a trans-ethnic meta-analysis. We observe a high concordance in the direction of effects across racial/ethnic groups, a high correlation of effect sizes between high-density lipoprotein and triglycerides, a modest overlap of associations with epigenome-wide association studies of other cardio-metabolic traits, and a largely non-overlap with lipid loci identified to date through genome-wide association studies. Thirty CpGs reached significance in at least 2 racial/ethnic groups including 7 that showed association with the expression of an annotated gene. CpGs annotated to CPT1A showed evidence of being influenced by triglycerides levels. DNA methylation levels of circulating leukocytes show robust and consistent association with blood lipid levels across multiple racial/ethnic groups., Abnormal blood lipid levels are important risk factors for cardiovascular and other various diseases. Here the authors conduct a large-scale multi-ethnic epigenome-wide association study combined with epigenetic (cis-QTL and eQTM) data, and identify CpG-lipid traits associations that are specific to or common across racial/ethnic groups.

The combined use of Global Positioning System (GPS) technology and motion sensors within the discipline of movement ecology has increased over recent years. This is particularly the case for instrumented wildlife, with many studies now opting to record parameters at high (infra-second) sampling frequency. However, the detail with which GPS loggers can elucidate fine-scale movement depends on the precision and accuracy of fixes, with accuracy (specifically, location error and fix success rate) being affected by signal reception. We hypothesised that animal behaviour was the main factor affecting fix inaccuracy (particularly for collar-mounted tags sampling at high frequency). In conjunction to this, inherent GPS positional noise (‘jitter’), would be most apparent during GPS fixes for non-moving locations, thereby producing disproportionate error during rest periods. A Movement Verified Filtering (MVF) protocol was constructed to compare GPS-derived speed data to dynamic body acceleration (DBA). This was collected by a simultaneously deployed tri-axial accelerometer, to provide a computationally quick method for identifying genuine travelling movement. This method was tested on 11 free-ranging lions ( Panthera leo ) within the Kgalagadi Transfrontier park in the Kalahari Desert, fitted with collar-mounted GPS units and tri-axial motion sensors (Daily Diary; DD) recording at 1 and 40 Hz, respectively. The findings support the hypothesis and show that distance moved estimates were, on average, overestimated by > 80 % prior to GPS screening. We present the conceptual and mathematical protocols for screening fix inaccuracy within high resolution GPS datasets. We demonstrate the importance that MVF has for avoiding inaccurate and biased estimates of movement and caution the accuracy of findings from previous studies that employed minimal GPS pre-processing . Throughout, we address the applicability of comparing fine-scale indices of GPS- and motion sensor-borne data in tandem to qualify animal behaviour.

Background Animal-attached devices can be used on cryptic species to measure their movement and behaviour, enabling unprecedented insights into fundamental aspects of animal ecology and behaviour. However, direct observations of subjects are often still necessary to translate biologging data accurately into meaningful behaviours. As many elusive species cannot easily be observed in the wild, captive or domestic surrogates are typically used to calibrate data from devices. However, the utility of this approach remains equivocal. Methods Here, we assess the validity of using captive conspecifics, and phylogenetically-similar domesticated counterparts (surrogate species) for calibrating behaviour classification. Tri-axial accelerometers and tri-axial magnetometers were used with behavioural observations to build random forest models to predict the behaviours. We applied these methods using captive Alpine ibex (Capra ibex) and a domestic counterpart, pygmy goats (Capra aegagrus hircus), to predict the behaviour including terrain slope for locomotion behaviours of captive Alpine ibex. Results Behavioural classification of captive Alpine ibex and domestic pygmy goats was highly accurate (> 98%). Model performance was reduced when using data split per individual, i.e., classifying behaviour of individuals not used to train models (mean ± sd = 56.1 ± 11%). Behavioural classifications using domestic counterparts, i.e., pygmy goat observations to predict ibex behaviour, however, were not sufficient to predict all behaviours of a phylogenetically similar species accurately (> 55%). Conclusions We demonstrate methods to refine the use of random forest models to classify behaviours of both captive and free-living animal species. We suggest there are two main reasons for reduced accuracy when using a domestic counterpart to predict the behaviour of a wild species in captivity; domestication leading to morphological differences and the terrain of the environment in which the animals were observed. We also identify limitations when behaviour is predicted in individuals that are not used to train models. Our results demonstrate that biologging device calibration needs to be conducted using: (i) with similar conspecifics, and (ii) in an area where they can perform behaviours on terrain that reflects that of species in the wild.

Background DNA methylation is a key epigenetic modification that can directly affect gene regulation. DNA methylation is highly influenced by environmental factors such as cigarette smoking, which is causally related to chronic obstructive pulmonary disease (COPD) and lung cancer. To date, there have been few large-scale, combined analyses of DNA methylation and gene expression and their interrelations with lung diseases. Results We performed an epigenome-wide association study of whole blood gene expression in ~ 6000 individuals from four cohorts. We discovered and replicated numerous CpGs associated with the expression of cis genes within 500 kb of each CpG, with 148 to 1,741 cis CpG-transcript pairs identified across cohorts. We found that the closer a CpG resided to a transcription start site, the larger its effect size, and that 36% of cis CpG-transcript pairs share the same causal genetic variant. Mendelian randomization analyses revealed that hypomethylation and lower expression of CHRNA5, which encodes a smoking-related nicotinic receptor, are causally linked to increased risk of COPD and lung cancer. This putatively causal relationship was further validated in lung tissue data. Conclusions Our results provide a large and comprehensive association study of whole blood DNA methylation with gene expression. Expression platform differences rather than population differences are critical to the replication of cis CpG-transcript pairs. The low reproducibility of trans CpG-transcript pairs suggests that DNA methylation regulates nearby rather than remote gene expression. The putatively causal roles of methylation and expression of CHRNA5 in relation to COPD and lung cancer provide evidence for a mechanistic link between patterns of smoking-related epigenetic variation and lung diseases, and highlight potential therapeutic targets for lung diseases and smoking cessation.

Background The discovery of robust and trans-ethnically replicated DNA methylation markers of metabolic phenotypes, has hinted at a potential role of epigenetic mechanisms in lipid metabolism. However, DNA methylation and the lipid compositions and lipid concentrations of lipoprotein sizes have been scarcely studied. Here, we present an epigenome-wide association study (EWAS) (N = 5414 total) of mostly lipid-related metabolic measures, including a fine profiling of lipoproteins. As lipoproteins are the main players in the different stages of lipid metabolism, examination of epigenetic markers of detailed lipoprotein features might improve the diagnosis, prognosis, and treatment of metabolic disturbances. Results We conducted an EWAS of leukocyte DNA methylation and 226 metabolic measurements determined by nuclear magnetic resonance spectroscopy in the population-based KORA F4 study (N = 1662) and replicated the results in the LOLIPOP, NFBC1966, and YFS cohorts (N = 3752). Follow-up analyses in the discovery cohort included investigations into gene transcripts, metabolic-measure ratios for pathway analysis, and disease endpoints. We identified 161 associations (p value −10), covering 16 CpG sites at 11 loci and 57 metabolic measures. Identified metabolic measures were primarily medium and small lipoproteins, and fatty acids. For apolipoprotein B-containing lipoproteins, the associations mainly involved triglyceride composition and concentrations of cholesterol esters, triglycerides, free cholesterol, and phospholipids. All associations for HDL lipoproteins involved triglyceride measures only. Associated metabolic measure ratios, proxies of enzymatic activity, highlight amino acid, glucose, and lipid pathways as being potentially epigenetically implicated. Five CpG sites in four genes were associated with differential expression of transcripts in blood or adipose tissue. CpG sites in ABCG1 and PHGDH showed associations with metabolic measures, gene transcription, and metabolic measure ratios and were additionally linked to obesity or previous myocardial infarction, extending previously reported observations. Conclusion Our study provides evidence of a link between DNA methylation and the lipid compositions and lipid concentrations of different lipoprotein size subclasses, thus offering in-depth insights into well-known associations of DNA methylation with total serum lipids. The results support detailed profiling of lipid metabolism to improve the molecular understanding of dyslipidemia and related disease mechanisms.

Background Studies on the relationship between renal function and the human plasma proteome have identified several potential biomarkers. However, investigations have been conducted largely in European populations, and causality of the associations between plasma proteins and kidney function has never been addressed. Methods A cross-sectional study of 993 plasma proteins among 2,882 participants in four studies of European and admixed ancestries (KORA, INTERVAL, HUNT, QMDiab) identified trans-ethnic associations between eGFR/CKD and proteomic biomarkers. For the replicated associations, two-sample bidirectional Mendelian randomization (MR) was used to investigate potential causal relationships. Publicly available datasets and transcriptomic data from independent studies were used to examine the association between gene expression in kidney tissue and eGFR . Results Fifty-seven plasma proteins were associated with eGFR, including one novel protein. Twenty-three of these were additionally associated with CKD. The strongest inferred causal effect was the positive effect of eGFR on testican-2, in line with the known biological role of this protein and the expression of its protein-coding gene (SPOCK2) in renal tissue. We also observed suggestive evidence of an effect of melanoma inhibitory activity (MIA), carbonic anhydrase III, and cystatin-M on eGFR. Conclusions In a discovery-replication setting, we identified 57 proteins trans-ethnically associated with eGFR. The revealed causal relationships are an important stepping-stone in establishing testican-2 as a clinically relevant physiological marker of kidney disease progression, and point to additional proteins warranting further investigation.

Ruminant urine patches are potential sites of reactive nitrogen (N) loss to the environment. Quantification of N losses from grazed grasslands requires measurement of the frequency of urine deposition, as well as its volume and chemical composition. However, studies to date are typically restricted to analyses of few replicate animals and urination events, especially for sheep. Here, we present data on urine frequency, volume, chemical composition (n = 193 events from n = 6 sheep) and metabolomic profile (n = 4–5 events from n = 4–5 sheep) from penned sheep. Differences in urine parameters and chemical composition data were compared seasonally and between two sites (improved and semi-improved pasture). Sheep urinated 8–11 times d−1, assuming time within pens represented a 24 h period. The mean urine event volume recorded was 289 ± 14 mL, from which we estimated a daily urine production value of 2.77 ± 0.15 L urine sheep−1 d−1. Daily urine N excretion and individual urine N concentrations were greater from sheep in improved pasture (26.7 ± 2.3 g N sheep−1 d−1; 7.0 ± 0.2 g N L−1) compared to those in semi-improved pasture (16.7 ± 1.2 g N sheep−1 d−1; 5.5 ± 0.4 g N L−1), but this did not equate to greater individual urine patch N loadings due to site differences in the urine-to-soil surface area influenced (17.5 L m-2 at the semi-improved site and 8.9 L m-2 at the improved site). Urine chemical composition varied seasonally and by site. Site- and season-specific urine should, therefore, be used in studies assessing N losses from urine patches. Based on the urine chemical composition data, we provide an updated artificial sheep urine ‘recipe’ which could be utilised to replicate natural sheep urine. The urine metabolomic profile clustered according to pasture quality, while clustering according to season was less evident. Our results provide important information for experimental and modelling studies assessing the scale and nature of N pollution arising from sheep-grazed pastures.

Vertebrates are recognized as sentient beings. Consequently, urgent priority is now being given to understanding the needs and maximizing the welfare of animals under human care. The general health of animals is most commonly determined by physiological indices e.g. blood sampling, but may also be assessed by documenting behaviour. Physiological health assessments, although powerful, may be stressful for animals, time-consuming and costly, while assessments of behaviour can also be time-consuming, subject to bias and suffer from a poorly defined link between behaviour and health. However, behaviour is recognized as having the potential to code for stress and well-being and could, therefore, be used as an indicator of health, particularly if the process of quantifying behaviour could be objective, formalized and streamlined to be time efficient. This study used Daily Diaries (DDs), (motion-sensitive tags containing tri-axial accelerometers and magnetometers), to examine aspects of the behaviour of bycaught loggerhead turtles, Caretta caretta in various states of health. Although sample size limited statistical analysis, significant behavioural differences (in terms of activity level and turn rate) were found between ‘healthy’ turtles and those with external injuries to the flippers and carapace. Furthermore, data visualization (spherical plots) clearly showed atypical orientation behaviour in individuals suffering gas emboli and intestinal gas, without complex data analysis. Consequently, we propose that the use of motion-sensitive tags could aid diagnosis and inform follow-up treatment, thus facilitating the rehabilitation process. This is particularly relevant given the numerous rehabilitation programs for bycatch sea turtles in operation. In time, tag-derived behavioural biomarkers, TDBBs for health could be established for other species with more complex behavioural repertoires such as cetaceans and pinnipeds which also require rehabilitation and release. Furthermore, motion-sensitive data from animals under human care and wild conspecifics could be compared in order to define a set of objective behavioural states (including activity levels) for numerous species housed in zoos and aquaria and/or wild species to help maximize their welfare.

Lipoprotein(a) [Lp(a)] is a major cardiovascular risk factor, which is largely genetically determined by one major gene locus, the LPA gene. Many aspects of the transcriptional regulation of LPA are poorly understood and the role of epigenetics has not been addressed yet. Therefore, we conducted an epigenome-wide analysis of DNA methylation on Lp(a) levels in two population-based studies (total n = 2208). We identified a CpG site in the LPA promoter which was significantly associated with Lp(a) concentrations. Surprisingly, the identified CpG site was found to overlap the SNP rs76735376. We genotyped this SNP de-novo in three studies (total n = 7512). The minor allele of rs76735376 (1.1% minor allele frequency) was associated with increased Lp(a) values (p = 1.01e-59) and explained 3.5% of the variation of Lp(a). Statistical mediation analysis showed that the effect on Lp(a) is rather originating from the base change itself and is not mediated by DNA methylation levels. This finding is supported by eQTL data from 208 liver tissue samples from the GTEx project, which shows a significant association of the rs76735376 minor allele with increased LPA expression. To evaluate, whether the association signal at rs76735376 may actually be derived from a stronger eQTL signal in LD with this SNP, eQTL association results of all correlated SNPs (r(2)>= 0.1) were integrated with genetic association results. This analysis pinpointed to rs10455872 as the potential trigger of the effect of rs76735376. Furthermore, both SNPs coincide with short apo(a) isoforms. Adjusting for both, rs10455872 and the apo(a) isoforms diminished the effect size of rs76735376 to 5.38 mg/dL (p = 0.0463). This indicates that the effect of rs76735376 can be explained by both an independent effect of the SNP and a strong correlation with rs10455872 and apo(a) isoforms.

Here we examine the association between DNA methylation in circulating leukocytes and blood lipids in a multi-ethnic sample of 16,265 subjects. We identify 148, 35, and 4 novel associations among Europeans, African Americans, and Hispanics, respectively, and an additional 186 novel associations through a trans-ethnic meta-analysis. We observe a high concordance in the direction of effects across racial/ethnic groups, a high correlation of effect sizes between high-density lipoprotein and triglycerides, a modest overlap of associations with epigenome-wide association studies of other cardio-metabolic traits, and a largely non-overlap with lipid loci identified to date through genome-wide association studies. Thirty CpGs reached significance in at least 2 racial/ethnic groups including 7 that showed association with the expression of an annotated gene. CpGs annotated to CPT1A showed evidence of being influenced by triglycerides levels. DNA methylation levels of circulating leukocytes show robust and consistent association with blood lipid levels across multiple racial/ethnic groups.

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 almost 30,000 whale shark encounter reports from 1992 to 2014, with more than 6000 individuals identified from 54 countries. During this time, the number of known whale shark aggregation sites (hotspots) increased from 13 to 20. Examination of photo-identification data at a global scale revealed a skewed sex-ratio bias toward males (overall, more than 66%) and high site fidelity among individuals, with limited movements of sharks between neighboring countries but no records confirming large, ocean basin-scale migrations. Citizen science has been vital in amassing large spatial and temporal data sets to elucidate key aspects of whale shark life history and demographics and will continue to provide substantial long-term value.

Bio-logging is becoming increasingly popular amongst wildlife researchers, providing a remote way of monitoring free-ranging animals in their natural habitats. However, capturing and tagging can be stressful and may alter animal behaviour. In this study, we investigated whether tagging altered activity and movement patterns of Eurasian beavers (Castor fiber) during the first week after release, predicting that beavers would be less active, travel shorter distances and stay closer to the lodge in the first nights after the tagging event. We captured 29 dominant free-ranging beavers (12 females, 17 males) in Telemark county, Norway, and tagged them with GPS units (n = 23; 12 males, 11 females) and tri-axial acceleration data loggers (n = 14; 9 males, 5 females). Accelerometer data was used to investigate activity levels (using mean overall dynamic body acceleration ODBA and principal activity periods), while GPS data was used to determine movement patterns (using distance moved and lodge displacement rate). Tagging effects were apparent only in activity levels of beavers, where we found lower mean ODBA values after release although the small effect size (Cohen’s d = 0.17) indicates only a minimal difference in activity. Neither principal activity periods nor distances moved or lodge displacement rate changed within the first week after release, which indicates that beavers were active and post-release space use within the territory was not affected by the tagging event in this respect.

Two prime issues can detrimentally affect animals that have been equipped with tags: (i) the effect of the capture and restraint process; and (ii) the effect of the tag itself. This work examines some of the issues surrounding quantification of tag effects on wild animals for both restrained and free-living animals. A new method to quantify stress effects based on monitoring ventilation rates in relation to activity is suggested for restrained animals which may help improve the practice of handling animals. It is also suggested that various metrics, many derived from accelerometers, can be examined in tagged wild animals to examine the change in behaviors over time with a view to having a better understanding of welfare issues, assuring the quality of recorded data and informing best practice.

The susceptibility to autoimmune diseases is influenced by genes encoding major histocompatibility complex (MHC) proteins. By examining the epigenetic methylation maps of cord blood samples, we found marked differences in the methylation status of CpG sites within the MHC genes (cis-metQTLs) between carriers of the type 1 diabetes risk haplotypes HLA-DRB1*03-DQA1*0501-DQB1*0201 (DR3-DQ2) and HLA-DRB1*04-DQA1*0301-DQB1*0302 (DR4-DQ8). These differences were found in children and adults, and were accompanied by reduced HLA-DR protein expression in immune cells with the HLA-DR3-DQ2 haplotype. Extensive cis-metQTLs were identified in all 45 immune and non-immune type 1 diabetes susceptibility genes analyzed in this study. We observed and validated a novel association between the methylation status of CpG sites within the LDHC gene and the development of insulin autoantibodies in early childhood in children who are carriers of the highest type 1 diabetes risk genotype. Functionally relevant epigenetic changes in susceptibility genes may represent therapeutic targets for type 1 diabetes.

In recent decades, biologists have sought to tag animals with various sensors to study aspects of their behavior otherwise inaccessible from controlled laboratory experiments. Despite this, chemical information, both environmental and physiological, remains challenging to collect despite its tremendous potential to elucidate a wide range of animal behaviors. In this work, we explore the design, feasibility, and data collection constraints of implantable, near-infrared fluorescent nanosensors based on DNA-wrapped single-wall carbon nanotubes (SWNT) embedded within a biocompatible poly(ethylene glycol) diacrylate (PEGDA) hydrogel. These sensors are enabled by Corona Phase Molecular Recognition (CoPhMoRe) to provide selective chemical detection for marine organism biologging. Riboflavin, a key nutrient in oxidative phosphorylation, is utilized as a model analyte in in vitro and ex vivo tissue measurements. Nine species of bony fish, sharks, eels, and turtles were utilized on site at Oceanogràfic in Valencia, Spain to investigate sensor design parameters, including implantation depth, sensor imaging and detection limits, fluence, and stability, as well as acute and long-term biocompatibility. Hydrogels were implanted subcutaneously and imaged using a customized, field-portable Raspberry Pi camera system. Hydrogels could be detected up to depths of 7 mm in the skin and muscle tissue of deceased teleost fish ( Sparus aurata and Stenotomus chrysops) and a deceased catshark ( Galeus melastomus). The effects of tissue heterogeneity on hydrogel delivery and fluorescence visibility were explored, with darker tissues masking hydrogel fluorescence. Hydrogels were implanted into a living eastern river cooter ( Pseudemys concinna), a European eel ( Anguilla anguilla), and a second species of catshark ( Scyliorhinus stellaris). The animals displayed no observable changes in movement and feeding patterns. Imaging by high-resolution ultrasound indicated no changes in tissue structure in the eel and catshark. In the turtle, some tissue reaction was detected upon dissection and histopathology. Analysis of movement patterns in sarasa comet goldfish ( Carassius auratus) indicated that the hydrogel implants did not affect swimming patterns. Taken together, these results indicate that this implantable form factor is a promising technique for biologging using aquatic vertebrates with further development. Future work will tune the sensor detection range to the physiological range of riboflavin, develop strategies to normalize sensor signal to account for the optical heterogeneity of animal tissues, and design a flexible, wearable device incorporating optoelectronic components that will enable sensor measurements in moving animals. This work advances the application of nanosensors to organisms beyond the commonly used rodent and zebrafish models and is an important step toward the physiological biologging of aquatic organisms.

Energy harvesting by animals is important because it provides the power needed for all metabolic processes. Beyond this, efficient food finding enhances individual fitness [1] and population viability [2], although rates of energy accumulation are affected by the environment and food distribution. Typically, differences between individuals in the rate of food acquisition are attributed to varying competencies [3], even though food-encounter rates are known to be probabilistic [4]. We used animal-attached technology to quantify food intake in four disparate free-living vertebrates (condors, cheetahs, penguins, and sheep) and found that inter-individual variability depended critically on the probability of food encounter. We modeled this to reveal that animals taking rarer food, such as apex predators and scavengers, are particularly susceptible to breeding failure because this variability results in larger proportions of the population failing to accrue the necessary resources for their young before they starve and because even small changes in food abundance can affect this variability disproportionately. A test of our model on wild animals indicated why Magellanic penguins have a stable population while the congeneric African penguin population has declined for decades. We suggest that such models predicting probabilistic ruin can help predict the fortunes of species operating under globally changing conditions.

Accelerometers are becoming ever more important sensors in animal-attached technology, providing data that allow determination of body posture and movement and thereby helping elucidate behaviour in animals that are difficult to observe.We sought to validate the identification of sea turtle behaviours from accelerometer signals by deploying tags on the carapace of a juvenile loggerhead (Caretta caretta), an adult hawksbill (Eretmochelys imbricata) and an adult green turtle (Chelonia mydas) at Aquarium La Rochelle. We recorded tri-axial acceleration at 50Hz for each species for a full day while two fixed cameras recorded their behaviours. We identified behaviours from the acceleration data using two different supervised learning algorithms; Random Forest and Classification And Regression Tree (CART), treating the data from the adult animals as separate from the juvenile data. We achieved a global accuracy of 81.30% for the adult turtle CART model and 71.63% for the juvenile loggerhead, identifying 10 and 12 different behaviours, respectively. Equivalent figures were 86.96% for the hawksbill and green turtle Random Forest model and 79.49% for the loggerhead, for the same behaviours. The use of Random Forest combined with CART algorithms allowed us to understand the decision rules implicated in behaviour discrimination, and thus remove or group together some “confused” or underrepresented behaviours in order to get the most accurate models. This study is the first to validate accelerometer data to identify turtle behaviours and the approach can now be tested on other captive sea turtle species.

Poikilotherms and homeotherms have different, well-defined metabolic responses to ambient temperature (Ta), but both groups have high power costs at high temperatures. Sloths (Bradypus) are critically limited by rates of energy acquisition and it has previously been suggested that their unusual departure from homeothermy mitigates the associated costs. No studies, however, have examined how sloth body temperature and metabolic rate vary withTa. Here we measured the oxygen consumption (VO2) of eight brown-throated sloths (B. variegatus) at variableTa’s and found that VO2indeed varied in an unusual manner with what appeared to be a reversal of the standard homeotherm pattern. Sloth VO2increased withTa, peaking in a metabolic plateau (nominal ‘thermally-active zone’ (TAZ)) before decreasing again at higherTavalues. We suggest that this pattern enables sloths to minimise energy expenditure over a wide range of conditions, which is likely to be crucial for survival in an animal that operates under severe energetic constraints. To our knowledge, this is the first evidence of a mammal provisionally invoking metabolic depression in response to increasingTa’s, without entering into a state of torpor, aestivation or hibernation.

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 paired with simultaneously recorded accelerometer-derived metrics of activity obtained from three types of data-storage tags. This study examined whether a predictive relationship could be established between four different activity metrics (tail-beat frequency (TBF), tail-beat acceleration amplitude (TBAA), overall dynamic body acceleration (ODBA), and vectorial dynamic body acceleration (VeDBA)) and the swimming speed of A. fulvescens. Volitional Usof sturgeon ranged from 0.48 to 2.70 m·s−1(0.51–3.18 body lengths (BL)·s−1). Swimming speed increased linearly with all accelerometer-derived metrics, and when all tag types were combined, Usincreased 0.46 BL·s−1for every 1 Hz increase in TBF, and 0.94, 0.61, and 0.94 BL·s−1for every 1g increase in TBAA, ODBA, and VeDBA, respectively. Predictive relationships varied among tag types and tag-specific parameter estimates of Usare presented for all metrics. This use of acceleration data-storage tags demonstrated their applicability for the field quantification of sturgeon swimming speed.

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.

Background The evidence for epigenome-wide associations between smoking and DNA methylation continues to grow through cross-sectional studies. However, few large-scale investigations have explored the associations using observations for individuals at multiple time-points. Here, through the use of the Illumina 450K BeadChip and data collected at two time-points separated by approximately 7 years, we investigate changes in methylation over time associated with quitting smoking or remaining a former smoker, and those associated with continued smoking. Results Our results indicate that after quitting smoking the most rapid reversion of altered methylation occurs within the first two decades, with reversion rates related to the initial differences in methylation. For 52 CpG sites, the change in methylation from baseline to follow-up is significantly different for former smokers relative to the change for never smokers (lowest p-value 3.61 x 10-39 for cg26703534, gene AHRR). Most of these sites’ respective regions have been previously implicated in smoking-associated diseases. Despite the early rapid change, dynamism of methylation appears greater in former smokers vs never smokers even four decades after cessation. Furthermore, our study reveals the heterogeneous effect of continued smoking: the methylation levels of some loci further diverge between smokers and non-smokers, while others re-approach. Though intensity of smoking habit appears more significant than duration, results remain inconclusive. Conclusions This study improves the understanding of the dynamic link between cigarette smoking and methylation, revealing the continued fluctuation of methylation levels decades after smoking cessation and demonstrating that continuing smoking can have an array of effects. The results can facilitate insights into the molecular mechanisms behind smoking-induced disturbed methylation, improving the possibility for development of biomarkers of past smoking behavior and increasing the understanding of the molecular path from exposure to disease. Electronic supplementary material The online version of this article (10.1186/s12864-017-4198-0) contains supplementary material, which is available to authorized users.

Semi‐aquatic mammals have secondarily returned to the aquatic environment, although they spend a major part of their life operating in air. Moving both on land, as well as in, and under water is challenging because such species are considered to be imperfectly adapted to both environments. We deployed accelerometers combined with a depth sensor to study the diving behavior of 12 free‐living Eurasian beavers Castor fiber in southeast Norway between 2009 and 2011 to examine the extent to which beavers conformed with mass‐dependent dive capacities, expecting them to be poorer than wholly aquatic species. Dives were generally shallow (

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.

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 habitat use of whale sharks (Rhincodon typus) at Ningaloo Reef, Western Australia. Whale sharks showed a moderate reverse diel vertical migration but exhibited a clear crepuscular pattern in locomotory activity. Peak activity occurred at sunset, whereas vertical movement peaked prior to this. Typical ram surface filter feeding could be identified and occurred primarily during sunset and the first hours of night. At such times, direct observations indicated whale sharks were feeding on tropical krill swarms. Kinematic analysis of postural data and data from vertical movement suggests that whale sharks at Ningaloo spend ~8 min per day actively ram surface filter feeding. Considering the high biomass present in krill schools, it is estimated that whale sharks at Ningaloo have a similar energy intake as those at other aggregation sites. Diel patterns in activity and diving behaviour suggest that whale sharks have tuned their diving behaviour in anticipation of the formation of these high-density patches which appear to only be periodically, but predictably available at sunset. Our results confirm that diel patterns in vertical habitat selection and vertical movements do not necessarily reflect patterns in activity and foraging behaviour. Direct quantification of activity and behaviour is required in gaining accurate representation of diel activity patterns.

Energy management during the breeding season is crucial for central place foragers since parents need to feed themselves and their offspring while being spatially and temporally constrained. In this work, we used overall dynamic body acceleration as a measure of activity and also to allude to the foraging energy expenditure of breeding Imperial cormorants Phalacrocorax atriceps. We also analyzed how changes in the time or energy allocated to different activities affected the foraging trip energy expenditure and estimated the daily food requirements of the species. Birds spent 42 % of the total energy flying to and from the feeding areas and 16 % floating at sea. The level of activity underwater was almost 1.5 times higher for females than for males. The most expensive diving phase in terms of rate of energy expenditure was descending though the water column. The total foraging trip energy expenditure was particularly sensitive to variation in the amount of time spent flying. During the breeding season, adult cormorants breeding along the Patagonian coast would consume approximately 10,000 tons of food. Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina Fil: Wilson, Rory P.. University of Wales. Institute of Environmental Sustainability. Biological Sciences; Reino Unido Fil: Shepard, Emily L. C.. University of Wales. Institute of Environmental Sustainability. Biological Sciences; Reino Unido Fil: Quintana, Flavio Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina

Three Steller sea lions Eumetopias jubatus, trained to dive voluntarily to depths ranging from 10 to 50 m, were used to determine whether the relationship between activity and metabolic rate during a diving interval (MRDI, dive + surface interval) was affected by fasting (9 d) during the breeding season (spring through summer). We subsequently used the relationship between activity and MRDI to partition the metabolic costs between underwater breath-holding activity and surface breathing activities. We estimated activity from overall dynamic body accel- eration (ODBA) measured using a 3-axis accelerometer, and measured MRDI using flow-through respirometry. The relationship between ODBA-based activity and MRDI was not affected by fast- ing period, suggesting that ODBA can be used to predict energy expenditure regardless of nutri- tional state in the spring and summer. However, the relationship between ODBA and dive meta- bolic rate differs from the relationship between ODBA and the surface metabolic rate before diving. Partitioning MRDI into the metabolic cost of remaining at the surface versus swimming underwater suggests that the metabolic cost of diving for Steller sea lions is approximately 29% lower than when breathing at the surface. ODBA appears to be a reasonable proxy to estimate metabolic rate in marine mammals, but more detailed behavioral data may be required to accu- rately apply the method in the field.

DNA methylation (DNAm) has been revealed to play a role in various diseases. Here we performed epigenome-wide screening and validation to identify mortality-related DNAm signatures in a general population-based cohort with up to 14 years follow-up. In the discovery panel in a case-cohort approach, 11,063 CpGs reach genome-wide significance (FDR, DNA methylation is modulated by environmental factors and has a role in many complex diseases. Here, the authors find that methylation at specific DNA sites is associated with all-cause mortality, and a methylation-based risk score may be informative for risk assessment and stratification.

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. Birds with antenna-devices appeared to consume about 20% more energy than non-antenna birds during the descent phase of the dive. The balance of the birds while diving or resting on the water also appeared to be compromised by the presence of an antenna. Based on these first results and because transmitters are one of the most common methods used to track animals, it appears critical to determine what impact these devices, and particularly antenna, can have on their bearers and try minimize it.

Animals are not distributed randomly in space and time because their movement ecology is influenced by a variety of factors. Energy landscapes and the landscape of fear have recently emerged as largely independent paradigms, both reshaping our perspectives and thinking relating to the spatial ecology of animals across heterogeneous landscapes. We argue that these paradigms are not distinct but rather complementary, collectively providing a better mechanistic basis for understanding the spatial ecology and decision-making of wild animals. We discuss the theoretical underpinnings of each paradigm and illuminate their complementary nature through case studies, then integrate these concepts quantitatively by constructing quantitative pathways of movement modulated by energy and fear to elucidate the mechanisms underlying the spatial ecology of wild animals.

Thermoregulation could represent a significant fraction of the total energy budget of endotherms under unfavourable environmental conditions. This cost affects several traits of the ecology of an organism such as its behaviour, distribution, or life history. Heat produced by muscle contraction during activity can be used to pay for heat loss or thermoregulation in many species (known as “thermal substitution”). This study seeks to unite the effects of temperature, depth, and activity on the energetic costs of endotherm divers using the Magellanic penguin as model species and to evaluate whether penguins may benefit from thermal substitution. This species operates under highly variable temperature and depth conditions along its breeding range and provides an ideal natural experiment. A developed thermodynamic model describing foraging activity predicted that the major element affecting heat loss was depth, exacerbated by temperature. Birds living in colder waters are predicted to be able to minimize costs by executing shallower dives and benefit from thermal substitution by swimming faster, particularly during deeper dives. The model was evaluated in two contrasting scenarios: (1) when birds swim near the surface commuting to the foraging areas and (2) when birds dive to depth to forage. Activity data from tags on free-living penguins indicated two of these predictions were apparent; penguins generally travelled faster while commuting at the surface in colder waters, while birds from warmer water colonies dived deeper while foraging. Contrary to predictions, however, penguins swam slower at deeper depths during both descent and ascent phases of foraging dives. These results suggest that penguins may benefit from thermal substitution by swimming faster when birds perform shallow dives commuting to and back from foraging areas, but they provide no evidence of behavioural response (via swimming faster) for thermoregulation when diving to depth to forage. Reasons for this are discussed and include the relevance of prey abundance in 3-d space and maximizing dive duration by conserving oxygen reserves. The way the bird operates will have profound consequences for the energy needed and therefore necessary energy acquisition rates. Expansion of our findings to other diving endotherms might help explain both global activity patterns and energy flow in ecosystems. Fil: Ciancio Blanc, Javier Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Quintana, Flavio Roberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Sala, Juan Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Wilson, Rory P. Swansea University. College Of Sciences. Departament Of Biosciences; Reino Unido

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 swim bladder volume regulation. Direct observations show that some body-compressed, cave-refuging teleosts that nominally operate near neutral buoyancy may adopt unusual body attitudes within crevices. We hypothesize that these fishes may relax their buoyancy and posture control mechanisms during periods of rest. A prediction derived from this is that resting fish may adopt a wide range of roll angles (i.e., rotation about their longitudinal axis) inside caves. To quantify this behavior and for testing this hypothesis, triaxial accelerometers were deployed on free-living, cave-refuging Argentine sea bass Acanthistius patachonicus, and the relationship between roll angle and a proxy for activity (defined as the vectorial dynamic body acceleration, VeDBA) was analyzed. The results were compared with data available for three other species of fishes with disparate body forms and lifestyles: the pelagic whale shark Rhincodon typus, the dorsoventrally compressed benthic great sculpin Myoxocephalus polyacanthocephalus, and the fusiform and demersal Atlantic cod Gadus morhua. Inactive Argentine sea bass adopted a wide variety of roll angles, including extreme ones exceeding 80°, but had lower roll angles closer to an upright posture primarily associated with higher activity levels. In contrast, the great sculpin and Atlantic cod both rested at a close to upright roll angle but had higher activity levels associated with larger roll angles. Whale shark did not rest for the duration of the recorded period and also showed higher activity levels associated with larger roll angles. We propose that relaxation of buoyancy and posture control may help to reduce the metabolic rate in laterally compressed, cave-refuging fishes during periods of rest within crevices. Fil: Ciancio Blanc, Javier Ernesto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos 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: Beltramino, Lucas Esteban. Universidad Nacional de la Patagonia; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Gleiss, Adrian C.. Murdoch University; Australia Fil: Wright, Serena. Centre For Environment, Fisheries And Aquaculture Scien; Reino Unido Fil: Norman, Brad. Ecocean Inc; Austria Fil: Holton, Mark. Swansea University; Reino Unido Fil: Wilson, Rory P.. Swansea University; Reino Unido

Background Coastal aggregations of whale sharks, typically dominated by juvenile males and occurring seasonally, are now documented in many places around the world, including Ningaloo Reef, Western Australia (WA). This aggregation occurs during the Austral autumn and winter and supports a lucrative tourism industry which operates during the whale shark “season” (generally April – July). Despite being one of the most highly studied aggregations of whale sharks in the world, their location and movements outside this period remain poorly understood, but are critical for understanding long term population dynamics and for effective management and conservation. An earlier study by ECOCEAN, combining satellite tracking and citizen science sightings of whale sharks outside the “season” at Ningaloo Reef and elsewhere along the WA coast, indicates that whale sharks may move north and south along the coast throughout the year, and/or make relatively short migrations, rather than undertaking long, trans-oceanic migrations. To test this further, a novel satellite tagging programme, supported by The Western Australian Department of Education (The Department), aims to discover where the whale sharks are when they are not at Ningaloo Reef and determine whether there are other unidentified “hotspots” for foraging and/or migration, i.e. areas of habitat critical for whale sharks. This programme also aims to provide innovative learning opportunities for school children, to make them more aware of the biology and ecology of WA's marine emblem and the marine environment, as well as to encourage engagement with STEM (Science, Technology, Engineering and Maths) learning. Approach Satellite tags (Wildlife Computers SPOT tags) were deployed on 12 whale sharks (identified using photo-identification through the Wildbook for Whale Sharks) at Ningaloo Reef in July 2015 using a custom-made clamp attachment on the first dorsal fin, designed to have minimal impact on the animals. Tags were funded by 16 schools from around WA participating in a joint ECOCEAN - Western Australian Department of Education science learning programme. Tracks of the sharks are displayed publically on the ZoaTrack website (www.zoatrack.org/projects/243/ analysis) and were used by participating schools in an eight week teaching programme. Results Data from satellite tags deployed in 2015 are still being collected and will be analysed as part of an Honours project in 2016, however, the teaching programme proved highly successful: The Department developed a comprehensive suite of resources addressing science, technology, engineering, mathematics and arts subjects to support students to engage in authentic learning experiences, and classes from pre-primary through to senior high school were involved. Preliminary results from the tags show that all have successfully reported positional data, for periods ranging from 15 to 156 days (mean 93.4 ± 13.1 SE) (as at 31/12/15). Homing migrations, to the southern part of Ningaloo Reef, have been recorded for 50% of all the sharks tagged, within periods ranging from 44 to 93 days (mean 65.7 ± 7.8 SE). These data show sharks making short forays away from Ningaloo Reef, and reveal areas important for commuting and foraging. Conclusions This innovative approach to funding allowed the satellite tracking programme to proceed and not only provided new information on the movements of whale sharks from Ningaloo Reef that can be used for conservation planning and management, but also provided novel learning experiences for school children and raised awareness for whale shark conservation and the marine environment. The data gathered support the hypothesis that whale sharks from the Ningaloo Reef aggregation do not typically undertake ocean basin scale migrations, rather they make shorter forays, perhaps to exploit food resources that vary spatially and temporally, and could be used to benchmark conservation outcomes for WA whale sharks and to provide pathways for more effective protection.

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 swimming capacity. Triaxial accelerometers were used to estimate the energetic expenditure of adult lake sturgeon (Acipenser fulvescens) swimming through a vertical slot fishway, to determine whether individual behaviour or path selection, resulting in differences in cumulative energy use, explain fishway passage success. Most individuals attempted to pass the fishway (n=30/44; 68%), although successful passage only occurred for a subset of those attempting (n=7/30; 23%). High-speed swimming was rarely observed during upstream passage through fishway basins, and was of short duration. Two turning basins delayed passage, subsequently resulting in a higher energetic cost. The rate at which energy was expended did not differ among successful and unsuccessful individuals, although successful sturgeon exhibited higher costs of transport (42.75 versus 25.85 J kg−1 m−1). Energy expenditure metrics were not predictive of successful fishway passage, leading us to conclude that other endogenous or exogenous factors influence passage success. In a practical application of field measurements of energy expenditure, we demonstrate that fishway passage through a structure designed to facilitate migration does result in an energetic loss for lake sturgeon (3249–16,331 J kg−1), equivalent to individuals travelling 5.8–28.2 km in a lentic system.

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 biological data over large geographic areas is simply not feasible by a single team of researchers. But in the current age of a well-educated public and accessible and mobile digital technology, scientists are now able to harness the observations of many, thus infinitely increasing their power of observation. Despite its status as the world's largest fish, there remains a paucity of information on the biology and ecology of whale sharks (Rhincodon typus). This species is however a prime target for ‘citizen science’ monitoring because of its charismatic nature, presence at many coastal aggregation sites and the growth of ecotourism around this species. Approach Information on whale shark sightings worldwide can be gathered by various stakeholders and stored in the Wildbook for Whale Sharks (www.whaleshark.org) database. Whale shark identification images are collected when a swimmer photographs the individual's unique spot pattern immediately behind the gill slits, which is distinct and long-lasting, and this image (with associated sighting data and information on shark size and sex) is then submitted to the online database. Computer-assisted scanning technology is then employed to determine whether the individual whale shark in question is a ‘new’ shark or a ‘resight’ of a previously reported whale shark within the database. Wildbook can then be queried to gain insights on various aspects of whale shark biology and ecology from data available at the various global hotspots. Results Members of the public and researchers alike contributed in this collaborative citizen science project enabling (as of 31 December 2014) almost 30000 whale shark encounter reports, comprising 6300+ individuals from 54 countries, to be identified. The number of recognized global aggregation sites (constellations) has increased from 13 to 20. The majority of these (14 out of 20) show a marked sex-ratio bias towards males (>66%). Site fidelity is relatively high, with an overall mean percentage of sharks returning to the 20 hotspots in two or more years of 35.7% (to a maximum of 21 years). Despite photo-identification revealing movements of sharks between a number of neighbouring countries/regions, there are no records confirming large, ocean basin-scale migrations. Strong seasonality in sightings is evident at many locations, suggesting that in general, that these aggregations are frequently exploiting known coastal feeding opportunities. Conclusions This study demonstrates the utility of citizen science in amassing large datasets and their utility in elucidating key aspects of whale shark life-history and demographics.

Acceleration data loggers can be used to construct time–energy budgets or identify specific behaviours in free living animals. Within a marine context such devices have been largely deployed on vertebrates with comparatively little attention paid to commercially important invertebrates such as cephalopod molluscs. Here we tested the utility of tri-axial accelerometers to tease apart six discrete behaviours in the common cuttlefish Sepia officinalis. By considering depth profiles in conjunction with body pitch and roll and overall dynamic body acceleration we were able to make distinctions between resting at the seabed, active swimming, mating, post-coital panting and active manoeuvring along the seabed.

SUMMARYIncreasing experience in long-lived species is fundamental to improving breeding success and ultimately individual fitness. Diving efficiency of marine animals is primarily determined by their physiological and mechanical characteristics. This efficiency may be apparent via examination of biomechanical performance (e.g. stroke frequency and amplitude, change in buoyancy or body angle, etc.), which itself may be modulated according to resource availability, particularly as a function of depth. We investigated how foraging and diving abilities vary with age in a long-lived seabird. During two breeding seasons, small accelerometers were deployed on young (5 year old) and older (8/9 year old) brooding king penguins (Aptenodytes patagonicus) at the Crozet Archipelago, Indian Ocean. We used partial dynamic body acceleration (PDBA) to quantify body movement during dive and estimate diving cost. During the initial part of the descent, older birds exerted more effort for a given speed but younger penguins worked harder in relation to performance at greater depths. Younger birds also worked harder per unit speed for virtually the whole of the ascent. We interpret these differences using a model that takes into account the upthrust and drag to which the birds are subjected during the dive. From this, we suggest that older birds inhale more at the surface but that an increase in the drag coefficient is the factor leading to the increased effort to swim at a given speed by the younger birds at greater depths. We propose that this higher drag may be the result of young birds adopting less hydrodynamic postures or less direct trajectories when swimming or even having a plumage in poorer condition.

In long-lived species such as seabirds, foraging success is considered to be related to breeding success, so quantification of foraging parameters during the breeding season should help understand population trends. Using GPS units, we studied the foraging effort of 55 breeding Magellanic penguins Spheniscus magellanicus from 5 colonies in coastal Patagonia, Argentina (42 to 54°S): Punta Norte, Bahia Bustamante, Puerto Deseado, Puerto San Julian and Isla Martillo, in an attempt to relate this to differences in breeding population trends. Measures of foraging effort—trip duration, total distance covered and maximun distance of the foraging trips from the breeding colony—decreased with increasing rate of population change. This information sug- gests that there are large differences in foraging effort and success among Patagonian penguin colonies, and penguins from Bahia Bustamante and Puerto Deseado, which are in the centre of the geographic range, require the highest foraging effort but are the least successful. It is plausible that lower population growth rates in these 2 colonies stem from the differences in food availabil- ity rather than any other process on land.

Biologging data have provided important insights into the biology of marine mam- mals, sea turtles, birds, fish, and some invertebrates. These techniques have primarily targeted adult organisms. As a result, the early life histories of many marine species are still poorly under- stood. Technological advances have enabled attachment of smaller tags to young animals, although equipment limitations, access to and capture/handling of animals, and equipment and data recovery pose additional challenges to researchers. In this Theme Section, we highlight novel uses of biologging data on juvenile animals, including reviews of tagging efforts on multiple life- history stages and the integration of oceanographic data in tagging efforts.

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Current guidelines for instrumenting birds state that external devices should not exceed 3–5% of the birds’ body mass; however, the energetic consequences of carrying any given device mass are likely to vary according to the morphology and ecology of the species concerned. We used a freeware program to estimate the mechanical power requirements of flight at the minimum power speed for 80 species of flying seabird from 8 major groups with payloads of increasing mass. Devices representing 3% of the bird’s body mass resulted in an increase in energy expenditure for flight ranging from 4.67 to 5.71% without accounting for the increase in body drag coefficient associated with external devices. This effect differed within and between seabird lineages with members of the Alcidae and Phalacrocoracidae experiencing the highest energetic costs of any increase in device mass. We propose that device effects on seabirds could be further reduced through consideration of species-specific effects of added payload and drag.

Intersexual differences in the foraging behaviour have been examined in several seabird species, especially those exhibiting sexual size dimorphism. We studied intersex behavioural differences in the Imperial Cormorant (Phalacrocorax atriceps), a size dimorphic seabird. Twenty adults (11 females and 9 males), breeding at Punta León (43°04′S; 64°2′W), Chubut, Argentina, were equipped with loggers to measure tri-axial acceleration and depth, to calculate the foraging trip time/activity budgets and diving behaviour. Both sexes had similar foraging trip durations, spending a similar proportion of the foraging time flying and floating on the sea surface. However, females spent more time underwater, executing more and shallower dives. Females also recovered more quickly than males from dives performed to depths of less than 30 m and spent more time foraging along the bottom at any depth than males. We conclude that if allometric effects affect the foraging behaviour of Imperial Cormorants, they only do so during diving because no differences were observed in the total amount of time sexes spent flying or foraging. Geschlechtsunterschiede bei der Nahrungsaufnahme wurden bereits für mehrere Seevögel beschrieben, besonders für solche mit geschlechtsabhängiger Körpergröße. Wir untersuchten geschlechtsspezifische Verhaltensunterschiede bei der Blauaugenscharbe, einem Seevogel mit geschlechtsbedingt unterschiedlicher Körpergröße. Achtundzwanzig adulte Tiere (11 Weibchen, 9 Männchen), die bei Punta León (43°04′S; 64°2′W), Chubut, Argentinien, brüteten, wurden mit Datenloggern zur Aufzeichnung ihrer drei-achsigen Beschleunigung und Tauchtiefe versehen, um ihre Zeit- und Aktivitäts-Budgets und ihr Tauchverhalten zu messen. Beide Geschlechter verbrachten etwa gleich viel Zeit bei ihren Ausflügen zur Nahrungssuche, mit in etwa auch gleich großen Zeit-Anteilen für Fliegen und Treiben auf dem Wasser. Aber die Weibchen verbrachten mehr Zeit unter Wasser bei häufigeren Tauchgängen in flacherem Wasser. Sie erholten sich auch rascher als die Männchen von Tauchgängen in Tiefen bis zu 30 Meter und verbrachten in jeder Tiefe mehr Zeit als die Männchen bei der Nahrungsaufnahme am Grund. Wir schließen hieraus, dass, wenn allometrische Effekte das Nahrungsaufnahme-Verhalten von Blauaugenscharben überhaupt beeinflussen, diese Einflüsse nur beim Tauchen auftreten, da in der Zeit, die fliegend oder für die Nahrungsaufnahme verbracht wurde, kein Geschlechtsunterschied festgestellt werden konnten. Fil: Gómez Laich, Agustina Marta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Quintana, Flavio Roberto. Wildlife Conservation Society; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina Fil: Shepard, E. L. C.. University of Wales; Reino Unido Fil: Wilson, R. P.. University of Wales; Reino Unido

Marine food web dynamics are determined by interactions within and between species and between species and their environment. Global change directly affects abiotic conditions and living organisms, impinging on all trophic levels in food webs. Different groups of marine researchers traditionally study different aspects of these changes. However, over medium to long time scales perturbations affecting food webs need to be considered across the full range from nutrients to top predators. Studies of end-to-end marine food webs not only span organism sizes and trophic levels, but should also help align multidisciplinary research to common goals and perspectives. Topics are described that bridge disciplinary gaps and are needed to develop new understanding of the reciprocal impacts of global change on marine food webs and ocean biogeochemistry. These include (1) the effects of nutrients on biomass and production, (2) the effects of varying element ratios on food web structure and food quality, (3) bulk flows of energy and material in food webs and their efficiencies of transfer, (4) the ecological effects of species richness and the roles of microbial organisms, (5) the role of feeding behaviour in food web dynamics and trophic controls, (6) the spatial dynamics of communities and links between different food webs, (7) the combined effects of body size and behaviour in determining dynamics of food webs, and (8) the extent to which the ability of marine organisms (and communities) to adapt will influence food web dynamics. An overriding issue that influences all topics concerns the time and space scales of ecosystem variability. Threads link different nodes of information among various topics, emphasizing the importance of tackling food web studies with a variety of modelling approaches and through a combination of field and experimental studies with a strong comparative approach.

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.

The rate at which animals ingest food is a fundamental part of animal ecology although it is rarely quantified, with recently-developed animal-attached tags providing a potentially viable approach. However, to date, these methods lack clarity in differentiating various eating behaviours, such as ‘chewing’ from ‘biting’. The aims of this study were to examine the use of inter-mandibular angle sensors (IMASENs), to quantify grazing behaviour in herbivores including cattle (Bos taurus), sheep (Ovis aries) and pygmy goats (Capra aegagrus hircus) eating different foodstuffs. Specifically, we aimed to: (1) quantify jaw movements of each species and determine differences between biting and chewing; (2) assess whether different food types can be discerned from jaw movements; and (3) determine whether species-specific differences in jaw movements can be detected. Subjects were filmed while consuming concentrate, hay, grass and browse to allow comparison of observed and IMASEN-recorded jaw movements. This study shows that IMASENs can accurately detect jaw movements of feeding herbivores, and, based on the rate of jaw movements, can classify biting (taking new material into the mouth) from chewing (masticating material already in the mouth). The biting behaviours associated with concentrate pellets could be identified easily as these occurred at the fastest rate for all species. However, the rates of chewing different food items were more difficult to discern from one another. Comparison of chew:bite ratios of the various food types eaten by each species showed no differences. Species differences could be identified using bite and chew rates. Cattle consistently displayed slower bite and chew rates to sheep and pygmy goats when feeding, while sheep and pygmy goats showed similar bite and chew rates when feeding on concentrate pellets. Species-specific differences in chew:bite ratios were not identified. Magnetometry has the potential to record quantitative aspects of foraging such as the feeding duration, food handling time and food type. This is of major importance for researchers interested in both captive (e.g., agricultural productivity) and wild animal foraging dynamics as it can provide quantitative data with minimal observer interference.

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.