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| Title | Breaking the sticks: a hierarchical change-point model for estimating ontogenetic shifts with stable isotope data | Type | Journal Article | ||
| Year | 2012 | Publication | Methods in Ecology and Evolution | Abbreviated Journal | |
| Volume | 3 | Issue | 2 | Pages | 281-290 |
| Keywords | Bayesian methods, linear models, modelling, population ecology, statistics, | ||||
| Abstract | 1.Stable isotopes are increasingly used in ecology to investigate ontogenetic shifts in foraging habitat (via 13C) and in trophic level (via 15N). These shifts are in essence an individual-level phenomenon, requiring repeated measures throughout the life of individuals, i.e. longitudinal data. Longitudinal data require in turn specifying an appropriate covariance structure. Here we present a hierarchical model to jointly investigate individual ontogenetic shifts in 13C and 15N values. 2.In a Bayesian framework, we used a Cholesky decomposition for estimating a moderately-sized covariance matrix, thereby directly estimating correlations between parameters describing time-series of isotopic measurements. We offer guidelines on how to select the covariance structure. 3.The approach is illustrated with a hierarchical change-point (or broken stick) model applied to a data set collected on Southern Elephant Seals, Mirounga leonina. Ontogenetic shifts in foraging habitat, following a juvenile and variable stage, were detected and interpreted as fidelity to a foraging strategy; while ontogenetic shifts in trophic level were more likely the result of complete independence from maternal resources followed by a gradual increase in trophic level as seals aged. 4.Specifying both an appropriate covariance and mean structure enabled us to draw strong inferences on the ecology of an elusive marine predator, and has wide applicability for isotopic ecology provided repeated isotopic measurements are available.
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| Programme | 109 | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Blackwell Publishing Ltd | Place of Publication | Editor | ||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
ISSN  |
2041-210X | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 3863 | |||
| Permanent link to this record | |||||
| Author | |||||
| Title | Tracking prospecting movements involved in breeding habitat selection: insights, pitfalls and perspectives | Type | Journal Article | ||
| Year | 2013 | Publication | Methods in Ecology and Evolution | Abbreviated Journal | |
| Volume | 4 | Issue | 2 | Pages | 143-150 |
| Keywords | biotelemetry, breeding habitat choice, dispersal decisions, individual strategies, social information, spatial population ecology, | ||||
| Abstract | 1. Prospecting allows individuals to gather information on the local quality of potential future breeding sites. In a variable and heterogeneous environment, it plays a major role in breeding habitat selection and potentially helps individuals make optimal dispersal decisions. Although prospecting movements, involving visits to other breeding sites, have been observed in many species at relatively fine spatial scales, little is known about their occurrence at larger scales. Furthermore, the adaptive value of dispersal strategies in response to environmental changes remain poorly investigated.
2. Here, our main objective is to highlight in what ways tracking devices could constitute powerful tools to study prospecting behaviours at various spatial scales. First, we stress the importance of considering prospecting movements involved in breeding habitat selection and we detail the type of data that can be collected. Then, we review the advantages and constraints associated with the use of tracking devices in this context and we suggest new perspectives to investigate the behavioural strategies adopted by individuals during breeding habitat selection processes and dispersal decisions. 3. The rapid development of new powerful electronic tools for tracking individual behaviour thus opens a wide range of opportunities. More specifically, it may allow a more thorough understanding of the role of scale-dependent dispersal behaviour in population responses to environmental changes. |
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| Programme | 333 | ||||
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| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
2041-210X | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 3981 | |||
| Permanent link to this record | |||||
| Author | Fouchet D, Santin-Janin H, Sauvage F, Yoccoz N G, Pontier D, | ||||
| Title | An R package for analyzing survival using continuous-time open capture-recapture models | Type | Journal Article | ||
| Year | 2015 | Publication | Methods in Ecology and Evolution | Abbreviated Journal | |
| Volume | Issue | Pages | |||
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| Abstract | |||||
| Programme | 279 | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
2041-210X | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 6235 | |||
| Permanent link to this record | |||||
| Author | Cox Sam L., Orgeret Florian, Gesta Mathieu, Rodde Charles, Heizer Isaac, Weimerskirch Henri, Guinet Christophe, O'Hara Robert B. | ||||
| Title | Processing of acceleration and dive data on?board satellite relay tags to investigate diving and foraging behaviour in free?ranging marine predators | Type | Journal | ||
| Year | 2017 | Publication | Methods in Ecology and Evolution | Abbreviated Journal | |
| Volume | 9 | Issue | 1 | Pages | 64-77 |
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| Abstract | |||||
| Programme | 109 | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
2041-210X | ISBN | 2041-210X | Medium | |
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 6658 | |||
| Permanent link to this record | |||||
| Author | Stier Antoine, Romestaing Caroline, Schull Quentin, Lefol Emilie, Robin Jean?Patrice, Roussel Damien, Bize Pierre, Davey Matthew | ||||
| Title | How to measure mitochondrial function in birds using red blood cells: a case study in the king penguin and perspectives in ecology and evolution | Type | Journal | ||
| Year | 2017 | Publication | Methods in Ecology and Evolution | Abbreviated Journal | |
| Volume | 8 | Issue | 10 | Pages | 1172-1182 |
| Keywords | erythrocyte high?resolution respirometry metabolism mitochondria non?invasive methodology | ||||
| Abstract | |||||
| Programme | 119,131 | ||||
| Campaign | |||||
| Address | |||||
| Corporate Author | Thesis | Bachelor's thesis | |||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
2041-210X | ISBN | 2041-210X | Medium | |
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 6795 | |||
| Permanent link to this record | |||||
| Author | Sam L. Cox, Florian Orgeret, Mathieu Gesta, Charles Rodde, Isaac Heizer, Henri Weimerskirch, Christophe Guinet | ||||
| Title | Processing of acceleration and dive data on-board satellite relay tags to investigate diving and foraging behaviour in free-ranging marine predators | Type | Journal | ||
| Year | 2018 | Publication | Methods in Ecology and Evolution | Abbreviated Journal | |
| Volume | 9 | Issue | 1 | Pages | 64-77 |
| Keywords | accelerometers animal biotelemetry Argos data abstraction Mirounga leonina prey catch attempts satellite data relaying southern elephant seal swimming effort | ||||
| Abstract | Biologging technologies are changing the way in which the marine environment is observed and monitored. However, because device retrieval is typically required to access the high-resolution data they collect, their use is generally restricted to those animals that predictably return to land. Data abstraction and transmission techniques aim to address this, although currently these are limited in scope and do not incorporate, for example, acceleration measurements which can quantify animal behaviours and movement patterns over fine-scales. In this study, we present a new method for the collection, abstraction and transmission of accelerometer data from free-ranging marine predators via the Argos satellite system. We test run the technique on 20 juvenile southern elephant seals Mirounga leonina from the Kerguelen Islands during their first months at sea following weaning. Using retrieved archival data from nine individuals that returned to the colony, we compare and validate abstracted transmissions against outputs from established accelerometer processing procedures. Abstracted transmissions included estimates, across five segments of a dive profile, of time spent in prey catch attempt (PrCA) behaviours, swimming effort and pitch. These were then summarised and compared to archival outputs across three dive phases: descent, bottom and ascent. Correlations between the two datasets were variable but generally good (dependent on dive phase, marginal R2 values of between .45 and .6 to >.9) and consistent between individuals. Transmitted estimates of PrCA behaviours and swimming effort were positively biased to those from archival processing. Data from this study represent some of the first remotely transmitted quantifications from accelerometers. The methods presented and analysed can be used to provide novel insight towards the behaviours and movements of free-ranging marine predators, such as juvenile southern elephant seals, from whom logger retrieval is challenging. Future applications could however benefit from some adaption, particularly to reduce positive bias in transmitted PrCA behaviours and swimming effort, for which this study provides useful insight. | ||||
| Programme | 109 | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
2041-210X | ISBN | 2041-210X | Medium | |
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 7116 | |||
| Permanent link to this record | |||||
| Author | Aidan D. Bindoff, Simon J. Wotherspoon, Christophe Guinet, Mark A. Hindell | ||||
| Title | Twilight-free geolocation from noisy light data | Type | Journal | ||
| Year | 2017 | Publication | Methods in Ecology and Evolution | Abbreviated Journal | |
| Volume | 9 | Issue | 5 | Pages | 1190-1198 |
| Keywords | animal tracking archival tag bird migration global location sensor Hidden Markov Models | ||||
| Abstract | |||||
| Programme | 1201 | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
2041-210X | ISBN | 2041-210X | Medium | |
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 7314 | |||
| Permanent link to this record | |||||
| Author | |||||
| Title | A remote-controlled observatory for behavioural and ecological research: A case study on emperor penguins | Type | Journal | ||
| Year | 2018 | Publication | Methods in Ecology and Evolution | Abbreviated Journal | |
| Volume | 9 | Issue | 5 | Pages | 1168-1178 |
| Keywords | animal colony Antarctica behaviour emperor penguin remote-controlled observatory time-lapse imaging | ||||
| Abstract | |||||
| Programme | 137 | ||||
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| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
2041-210X | ISBN | 2041-210X | Medium | |
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 7400 | |||
| Permanent link to this record | |||||
| Author | Nicolas E. Humphries, Henri Weimerskirch, David W. Sims | ||||
| Title | A new approach for objective identification of turns and steps in organism movement data relevant to random walk modelling | Type | Journal | ||
| Year | 2013 | Publication | Methods in Ecology and Evolution | Abbreviated Journal | |
| Volume | 4 | Issue | 10 | Pages | 930-938 |
| Keywords | |||||
| Abstract | |||||
| Programme | 109 | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
2041-210X | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8218 | |||
| Permanent link to this record | |||||
| Author | Taiki Adachi, Philip Lovell, James Turnbull, Mike A. Fedak, Baptiste Picard, Christophe Guinet, Martin Biuw, Theresa R. Keates, Rachel R. Holser, Daniel P. Costa, Daniel E. Crocker, Patrick J. O. Miller | ||||
| Title | Body condition changes at sea: Onboard calculation and telemetry of body density in diving animals | Type | Journal | ||
| Year | 2023 | Publication | Methods in Ecology and Evolution | Abbreviated Journal | |
| Volume | 14 | Issue | 6 | Pages | 1457-1474 |
| Keywords | animal health bio-logging body density buoyancy marine mammal real-time monitoring satellite transmission | ||||
| Abstract | The ability of marine mammals to accumulate sufficient lipid energy reserves is vital for mammals' survival and successful reproduction. However, long-term monitoring of at-sea changes in body condition, specifically lipid stores, has only been possible in elephant seals performing prolonged drift dives (low-density lipids alter the rates of depth change while drifting). This approach has limited applicability to other species. Using hydrodynamic performance analysis during transit glides, we developed and validated a novel satellite-linked data logger that calculates real-time changes in body density (?lipid stores). As gliding is ubiquitous amongst divers, the system can assess body condition in a broad array of diving animals. The tag processes high sampling rate depth and three-axis acceleration data to identify 5 s high pitch angle glide segments at depths >100 m. Body density is estimated for each glide using gliding speed and pitch to quantify drag versus buoyancy forces acting on the gliding animal. We used tag data from 24 elephant seals (Mirounga spp.) to validate the onboard calculation of body density relative to drift rate. The new tags relayed body density estimates over 200 days and documented lipid store accumulation during migration with good correspondence between changes in body density and drift rate. Our study provided updated drag coefficient values for gliding (Cd,f = 0.03) and drifting (Cd,s = 0.12) elephant seals, both substantially lower than previous estimates. We also demonstrated post-hoc estimation of the gliding drag coefficient and body density using transmitted data, which is especially useful when drag parameters cannot be estimated with sufficient accuracy before tag deployment. Our method has the potential to advance the field of marine biology by switching the research paradigm from indirectly inferring animal body condition from foraging effort to directly measuring changes in body condition relative to foraging effort, habitat, ecological factors and anthropogenic stressors in the changing oceans. Expanding the method to account for diving air volumes will expand the system's applicability to shallower-diving (<100 m) species, facilitating real-time monitoring of body condition in a broad range of breath-hold divers. | ||||
| Programme | 109, 1201 | ||||
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| Address | |||||
| Corporate Author | Thesis | Bachelor's thesis | |||
| Publisher | Place of Publication | Editor | |||
| Language | Summary Language | Original Title | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN |
2041-210X | ISBN | Medium | ||
| Area | Expedition | Conference | |||
| Notes | Approved | yes | |||
| Call Number | Serial | 8620 | |||
| Permanent link to this record | |||||