| |
Records |
Links |
|
Author  |
Alexandra T. Holland, Benoît Bergk Pinto, Rose Layton, Christopher J. Williamson, Alexandre M. Anesio, Timothy M. Vogel, Catherine Larose, Martyn Tranter |
|
| |
Title |
Over Winter Microbial Processes in a Svalbard Snow Pack: An Experimental Approach |
Type |
Journal |
| |
Year |
2020 |
Publication |
Frontiers in Microbiology |
Abbreviated Journal |
|
|
| |
Volume |
11 |
Issue |
|
Pages |
1029 |
|
| |
Keywords |
|
|
| |
Abstract |
Snow packs cover large expanses of Earth’s land surface, making them integral components of the cryosphere in terms of past climate and atmospheric proxies, surface albedo regulators, insulators for other Arctic environments and habitats for diverse microbial communities such as algae, bacteria and fungi. Yet, most of our current understanding of snow pack environments, specifically microbial activity and community interaction, is limited to the main microbial growing season during spring ablation. At present, little is known about microbial activity and its influence on nutrient cycling during the subfreezing temperatures and 24-h darkness of the polar winter. Here, we examined microbial dynamics in a simulated cold (−5°C), dark snow pack to determine polar winter season microbial activity and its dependence on critical nutrients. Snow collected from Ny-Ålesund, Svalbard was incubated in the dark over a 5-week period with four different nutrient additions, including glacial mineral particles, dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP) and a combined treatment of DIN plus DIP. Data indicate a consumption of dissolved inorganic nutrients, particularly DIN, by heterotrophic communities, suggesting a potential nitrogen limitation, contradictory to phosphorus limitations found in most aquatic environments. 16S amplicon sequencing also reveal a clear difference in microbial community composition in the particulate mineral treatment compared to dissolved nutrient treatments and controls, suggesting that certain species of heterotrophs living within the snow pack are more likely to associate with particulates. Particulate phosphorus analyses indicate a potential ability of heterotrophic communities to access particulate sources of phosphorous, possibly explaining the lack of phosphorus limitation. These findings have importance for understanding microbial activity during the polar winter season and its potential influences on the abundance and bioavailability of nutrients released to surface ice and downstream environments during the ablation season. |
|
| |
Programme |
1192 |
|
| |
Campaign |
|
|
| |
Address |
|
|
| |
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 |
1664-302X |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
yes |
|
| |
Call Number |
|
Serial |
7965 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Alexey Lyubushin |
|
| |
Title |
Global Seismic Noise Entropy |
Type |
Journal |
| |
Year |
2020 |
Publication |
Frontiers in Earth Science |
Abbreviated Journal |
|
|
| |
Volume |
8 |
Issue |
|
Pages |
558 |
|
| |
Keywords |
|
|
| |
Abstract |
Data of continuous records of low-frequency (periods from 2 to 1,000 min) seismic noise on a global network of 229 broadband stations located around the world for 23 years, 1997–2019, are analyzed. The daily values of the entropy of the distribution of the squares of the orthogonal wavelet coefficients are considered as an informative characteristic of noise. An auxiliary network of 50 reference points is introduced, the positions of which are determined from the clustering of station positions. For each reference point, a time series is calculated, consisting of 8,400 samples with a time step of 1 day, the values of which are determined as the medians of the entropy values at the five nearest stations that are operable during the given day. The introduction of a system of reference points makes it possible to estimate temporal and spatial changes in the correlation of noise entropy values around the world. Estimation in an annual sliding time window revealed a time interval from mid-2002 to mid-2003, when there was an abrupt change in the properties of global noise and an intensive increase in both average entropy correlations and spatial correlation scales began. This trend continues until the end of 2019, and it is interpreted as a feature of seismic noise which is connected with an increase in the intensity of the strongest earthquakes, which began with the Sumatran mega-earthquake of December 26, 2004 (M = 9.3). The values of the correlation function between the logarithm of the released seismic energy and the bursts of coherence between length of day and the entropy of seismic noise in the annual time window indicate the delay in the release of seismic energy relative to the coherence maxima. This lag is interpreted as a manifestation of the triggering effect of the irregular rotation of the Earth on the increase in global seismic hazard. |
|
| |
Programme |
133 |
|
| |
Campaign |
|
|
| |
Address |
|
|
| |
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 |
2296-6463 |
ISBN |
2296-6463 |
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
yes |
|
| |
Call Number |
|
Serial |
7889 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Alice Carravieri, Paco Bustamante, Pierre Labadie, Hélène Budzinski, Olivier Chastel, Yves Cherel |
|
| |
Title |
Trace elements and persistent organic pollutants in chicks of 13 seabird species from Antarctica to the subtropics |
Type |
Journal |
| |
Year |
2020 |
Publication |
Environment International |
Abbreviated Journal |
|
|
| |
Volume |
134 |
Issue |
|
Pages |
105225 |
|
| |
Keywords |
Albatrosses; Mercury; Penguins; Petrels; Selenium; Stable isotopes |
|
| |
Abstract |
Seabirds from remote regions are mainly exposed to environmental contaminants from non-point contamination of their food webs. Pre-fledging seabird chicks are fed by their parents with marine prey captured in the vicinity of breeding colonies. Contaminant concentrations in tissues of pre-fledging chicks can thus be mostly related to local dietary sources, and have the potential to unravel spatial patterns of environmental contamination in marine ecosystems. Here, mercury (Hg), 13 other trace elements, and 18 persistent organic pollutants (POPs) were quantified in blood of chicks across four breeding locations that encompass a large latitudinal range in the southern Indian Ocean (from Antarctica, through subantarctic areas, to the subtropics), over a single breeding season. Thirteen species of penguins, albatrosses and petrels were studied, including endangered and near-threatened species, such as Amsterdam albatrosses and emperor penguins. Blood Hg burdens varied widely between species, with a factor of ~50 between the lowest and highest concentrations (mean ± SD, 0.05 ± 0.01 and 2.66 ± 0.81 µg g−1 dry weight, in thin-billed prions and Amsterdam albatrosses, respectively). Species relying on Antarctic waters for feeding had low Hg exposure. Concentrations of POPs were low in chicks, with the exception of hexachlorobenzene. Contaminant concentrations were mainly explained by species differences, but feeding habitat (inferred from δ13C values) and chicks’ body mass also contributed to explain variation. Collectively, our findings call for further toxicological investigations in Amsterdam albatrosses and small petrel species, because they were exposed to high and diverse sources of contaminants, and in macaroni penguins, which specifically showed very high selenium concentrations. Capsule Seabird chicks from four distant sites in the southern Indian Ocean had contrasted blood metallic and organic contaminant patterns depending on species, feeding habitat and body mass. |
|
| |
Programme |
109 |
|
| |
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 |
0160-4120 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
yes |
|
| |
Call Number |
|
Serial |
7674 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Alice Gadea, Mathieu Fanuel, Anne-Cécile Le Lamer, Joël Boustie, Hélène Rogniaux, Maryvonne Charrier, Françoise Lohézic-Le Devehat |
|
| |
Title |
Mass Spectrometry Imaging of Specialized Metabolites for Predicting Lichen Fitness and Snail Foraging |
Type |
Journal |
| |
Year |
2020 |
Publication |
Plants |
Abbreviated Journal |
|
|
| |
Volume |
9 |
Issue |
1 |
Pages |
70 |
|
| |
Keywords |
Notodiscus hookeri Pseudocyphellaria crocata Chemical Ecology Lichens Lobariaceae Mass Spectrometry Imaging Optimal Defense Theory Specialized Metabolites |
|
| |
Abstract |
Lichens are slow-growing organisms supposed to synthetize specialized metabolites to protect themselves against diverse grazers. As predicted by the optimal defense theory (ODT), lichens are expected to invest specialized metabolites in higher levels in reproductive tissues compared to thallus. We investigated whether Laser Desorption Ionization coupled to Mass Spectrometry Imaging (LDI-MSI) could be a relevant tool for chemical ecology issues such as ODT. In the present study, this method was applied to cross-sections of thalli and reproductive tissues of the lichen Pseudocyphellaria crocata. Spatial mapping revealed phenolic families of metabolites. A quantification of these metabolites was carried out in addition to spatial imaging. By this method, accumulation of specialized metabolites was observed in both reproductive parts (apothecia and soralia) of P. crocata, but their nature depended on the lichen organs: apothecia concentrated norstictic acid, tenuiorin, and pulvinic acid derivatives, whereas soralia mainly contained tenuiorin and pulvinic acid. Stictic acid, tenuiorin and calycin, tested in no-choices feeding experiments, were deterrent for N. hookeri while entire thalli were consumed by the snail. To improve better knowledge in relationships between grazed and grazing organisms, LDI-MSI appears to be a complementary tool in ecological studies |
|
| |
Programme |
136 |
|
| |
Campaign |
|
|
| |
Address |
|
|
| |
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 |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
yes |
|
| |
Call Number |
|
Serial |
8265 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Alison Ming, V. Holly L. Winton, James Keeble, Nathan L. Abraham, Mohit C. Dalvi, Paul Griffiths, Nicolas Caillon, Anna E. Jones, Robert Mulvaney, Joël Savarino, Markus M. Frey, Xin Yang |
|
| |
Title |
Stratospheric Ozone Changes From Explosive Tropical Volcanoes: Modeling and Ice Core Constraints |
Type |
Journal |
| |
Year |
2020 |
Publication |
Journal of geophysical research: atmospheres |
Abbreviated Journal |
|
|
| |
Volume |
125 |
Issue |
11 |
Pages |
e2019JD032290 |
|
| |
Keywords |
Antarctica chemistry-climate modeling isotopes in ice cores ozone Samalas volcanic eruption |
|
| |
Abstract |
Major tropical volcanic eruptions have emitted large quantities of stratospheric sulfate and are potential sources of stratospheric chlorine although this is less well constrained by observations. This study combines model and ice core analysis to investigate past changes in total column ozone. Historic eruptions are good analogs for future eruptions as stratospheric chlorine levels have been decreasing since the year 2000. We perturb the preindustrial atmosphere of a chemistry-climate model with high and low emissions of sulfate and chlorine. The sign of the resulting Antarctic ozone change is highly sensitive to the background stratospheric chlorine loading. In the first year, the response is dynamical, with ozone increases over Antarctica. In the high HCl (2 Tg emission) experiment, the injected chlorine is slowly transported to the polar regions with subsequent chemical ozone depletion. These model results are then compared to measurements of the stable nitrogen isotopic ratio, , from a low snow accumulation Antarctic ice core from Dronning Maud Land (recovered in 2016–2017). We expect ozone depletion to lead to increased surface ultraviolet (UV) radiation, enhanced air-snow nitrate photochemistry and enrichment in in the ice core. We focus on the possible ozone depletion event that followed the largest volcanic eruption in the past 1,000 years, Samalas in 1257. The characteristic sulfate signal from this volcano is present in the ice core but the variability in dominates any signal arising from changes in ultraviolet from ozone depletion. Prolonged complete ozone removal following this eruption is unlikely to have occurred over Antarctica. |
|
| |
Programme |
1177 |
|
| |
Campaign |
|
|
| |
Address |
|
|
| |
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 |
2169-8996 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
yes |
|
| |
Call Number |
|
Serial |
7856 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Amandine Gamble, Henri Weimerskirch, Thierry Boulinier |
|
| |
Title |
Seabirds blinded by ticks |
Type |
Journal |
| |
Year |
2020 |
Publication |
Frontiers in Ecology and the Environment |
Abbreviated Journal |
|
|
| |
Volume |
18 |
Issue |
6 |
Pages |
322-322 |
|
| |
Keywords |
|
|
| |
Abstract |
In December 2017, on Possession Island (part of the Crozet Archipelago in the southern Indian Ocean), we observed two breeding white‐chinned petrels (Procellaria aequinoctialis ) with very high levels of tick (Ixodes kerguelenensis ) infestation on both eyes. This degree of infestation was likely responsible for the birds’ death. Although this rare observation may seem anecdotal, it reveals that ticks can be fatal for a long‐lived colonial seabird species, in this case one that is already under pressure from fisheries bycatch and predation by introduced black rats (Rattus rattus ). It also raises questions about the frequency and spatial distribution of such a phenomenon and the conditions that may have been responsible for its occurrence. Such high parasite loads imply high local tick abundances but also a lack of preening by the partner. Could this be linked to the recent death of the partner? Infestations by ticks can affect the health of hosts through blood loss, the injection of toxins, and the transmission of infectious agents. In this instance, the mechanical blocking of eyesight may also have affected the birds’ behavior. The potential impact of climate change on local parasitic infestation levels is another important question. Parasites and diseases can harm endangered species in polar and subpolar areas, and could play critical roles in some circumstances. |
|
| |
Programme |
1151 |
|
| |
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 |
1540-9309 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
yes |
|
| |
Call Number |
|
Serial |
7797 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Amandine Gamble, Romain Bazire, Karine Delord, Christophe Barbraud, Audrey Jaeger, Hubert Gantelet, Eric Thibault, Camille Lebarbenchon, Erwan Lagadec, Pablo Tortosa, Henri Weimerskirch, Jean-Baptiste Thiebot, Romain Garnier, Jérémy Tornos, Thierry Boulinier |
|
| |
Title |
Predator and scavenger movements among and within endangered seabird colonies: Opportunities for pathogen spread |
Type |
Journal |
| |
Year |
2020 |
Publication |
Journal of Applied Ecology |
Abbreviated Journal |
|
|
| |
Volume |
57 |
Issue |
2 |
Pages |
367-378 |
|
| |
Keywords |
conservation biology disease ecology dynamic space utilization individual heterogeneity movement ecology Pasteurella multocida sentinel species serology |
|
| |
Abstract |
The spatial structure of host communities is expected to constrain pathogen spread. However, predators and/or scavengers may connect distant host (sub)populations when foraging. Determining whether some individuals or populations play a prominent role in the spread of pathogens is critical to inform management measures. We explored movements and epidemiological status of brown skuas Stercorarius antarcticus, the only avian terrestrial consumer native of Amsterdam Island (Indian Ocean), to assess whether and how they could be involved in the spread of the bacterium Pasteurella multocida, which recurrently causes avian cholera outbreaks in endangered albatross and penguin species breeding on the island. High proportions of seropositive and DNA-positive individuals for P. multocida indicated that skuas are highly exposed to the pathogen and may be able to transmit it. Movement tracking revealed that the foraging ranges of breeding skuas largely overlap among individuals and expand all along the coasts where albatrosses and penguins nest, but not on the inland plateau hosting the endemic Amsterdam albatross Diomedea amsterdamensis. Considering the epidemiological and movement data, skua movements may provide opportunity for pathogen spread among and within seabird colonies. Synthesis and applications. This work highlights the importance of considering the behaviour and epidemiological status of predators and scavengers in disease dynamics because the foraging movements of individuals of such species can potentially limit the efficiency of local management measures in spatially structured host communities. Such species could thus represent priority vaccination targets to implement efficient management measures aiming at limiting pathogen spread and also be used as sentinels to monitor pathogen circulation and evaluate the effectiveness of management measures. |
|
| |
Programme |
109,1151 |
|
| |
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 |
1365-2664 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
yes |
|
| |
Call Number |
|
Serial |
7683 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Amandine Kaiser, Davide Faranda, Sebastian Krumscheid, Danijel Belušić, Nikki Vercauteren |
|
| |
Title |
Detecting Regime Transitions of the Nocturnal and Polar Near-Surface Temperature Inversion |
Type |
Journal |
| |
Year |
2020 |
Publication |
Journal of the atmospheric sciences |
Abbreviated Journal |
|
|
| |
Volume |
77 |
Issue |
8 |
Pages |
2921-2940 |
|
| |
Keywords |
|
|
| |
Abstract |
Abstract Many natural systems undergo critical transitions, i.e., sudden shifts from one dynamical regime to another. In the climate system, the atmospheric boundary layer can experience sudden transitions between fully turbulent states and quiescent, quasi-laminar states. Such rapid transitions are observed in polar regions or at night when the atmospheric boundary layer is stably stratified, and they have important consequences in the strength of mixing with the higher levels of the atmosphere. To analyze the stable boundary layer, many approaches rely on the identification of regimes that are commonly denoted as weakly and very stable regimes. Detecting transitions between the regimes is crucial for modeling purposes. In this work a combination of methods from dynamical systems and statistical modeling is applied to study these regime transitions and to develop an early warning signal that can be applied to nonstationary field data. The presented metric aims to detect nearing transitions by statistically quantifying the deviation from the dynamics expected when the system is close to a stable equilibrium. An idealized stochastic model of near-surface inversions is used to evaluate the potential of the metric as an indicator of regime transitions. In this stochastic system, small-scale perturbations can be amplified due to the nonlinearity, resulting in transitions between two possible equilibria of the temperature inversion. The simulations show such noise-induced regime transitions, successfully identified by the indicator. The indicator is further applied to time series data from nocturnal and polar meteorological measurements. |
|
| |
Programme |
1013 |
|
| |
Campaign |
|
|
| |
Address |
|
|
| |
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 |
0022-4928, 1520-0469 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
yes |
|
| |
Call Number |
|
Serial |
8151 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ana P. B. Carneiro, Elizabeth J. Pearmain, Steffen Oppel, Thomas A. Clay, Richard A. Phillips, Anne-Sophie Bonnet‐Lebrun, Ross M. Wanless, Edward Abraham, Yvan Richard, Joel Rice, Jonathan Handley, Tammy E. Davies, Ben J. Dilley, Peter G. Ryan, Cleo Small, Javier Arata, John P. Y. Arnould, Elizabeth Bell, Leandro Bugoni, Letizia Campioni, Paulo Catry, Jaimie Cleeland, Lorna Deppe, Graeme Elliott, Amanda Freeman, Jacob González‐Solís, José Pedro Granadeiro, David Grémillet, Todd J. Landers, Azwianewi Makhado, Deon Nel, David G. Nicholls, Kalinka Rexer‐Huber, Christopher J. R. Robertson, Paul M. Sagar, Paul Scofield, Jean-Claude Stahl, Andrew Stanworth, Kim L. Stevens, Philip N. Trathan, David R. Thompson, Leigh Torres, Kath Walker, Susan M. Waugh, Henri Weimerskirch, Maria P. Dias |
|
| |
Title |
A framework for mapping the distribution of seabirds by integrating tracking, demography and phenology |
Type |
Journal |
| |
Year |
2020 |
Publication |
Journal of Applied Ecology |
Abbreviated Journal |
|
|
| |
Volume |
57 |
Issue |
3 |
Pages |
514-525 |
|
| |
Keywords |
albatrosses at-sea threats conservation distributions longline fisheries megafauna petrels seabird density |
|
| |
Abstract |
The identification of geographic areas where the densities of animals are highest across their annual cycles is a crucial step in conservation planning. In marine environments, however, it can be particularly difficult to map the distribution of species, and the methods used are usually biased towards adults, neglecting the distribution of other life-history stages even though they can represent a substantial proportion of the total population. Here we develop a methodological framework for estimating population-level density distributions of seabirds, integrating tracking data across the main life-history stages (adult breeders and non-breeders, juveniles and immatures). We incorporate demographic information (adult and juvenile/immature survival, breeding frequency and success, age at first breeding) and phenological data (average timing of breeding and migration) to weight distribution maps according to the proportion of the population represented by each life-history stage. We demonstrate the utility of this framework by applying it to 22 species of albatrosses and petrels that are of conservation concern due to interactions with fisheries. Because juveniles, immatures and non-breeding adults account for 47%–81% of all individuals of the populations analysed, ignoring the distributions of birds in these stages leads to biased estimates of overlap with threats, and may misdirect management and conservation efforts. Population-level distribution maps using only adult distributions underestimated exposure to longline fishing effort by 18%–42%, compared with overlap scores based on data from all life-history stages. Synthesis and applications. Our framework synthesizes and improves on previous approaches to estimate seabird densities at sea, is applicable for data-poor situations, and provides a standard and repeatable method that can be easily updated as new tracking and demographic data become available. We provide scripts in the R language and a Shiny app to facilitate future applications of our approach. We recommend that where sufficient tracking data are available, this framework be used to assess overlap of seabirds with at-sea threats such as overharvesting, fisheries bycatch, shipping, offshore industry and pollutants. Based on such an analysis, conservation interventions could be directed towards areas where they have the greatest impact on populations. |
|
| |
Programme |
388 |
|
| |
Campaign |
|
|
| |
Address |
|
|
| |
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 |
1365-2664 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
yes |
|
| |
Call Number |
|
Serial |
7655 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Angus F. Henderson, Clive R. McMahon, Rob Harcourt, Christophe Guinet, Baptiste Picard, Simon Wotherspoon, Mark A. Hindell |
|
| |
Title |
Inferring Variation in Southern Elephant Seal At-Sea Mortality by Modelling Tag Failure |
Type |
Journal |
| |
Year |
2020 |
Publication |
Frontiers in Marine Science |
Abbreviated Journal |
|
|
| |
Volume |
7 |
Issue |
|
Pages |
796 |
|
| |
Keywords |
|
|
| |
Abstract |
Identifying factors influencing survivorship is key to understanding population persistence. Although satellite telemetry is a powerful tool for studying remote animal ecology and behaviour it is rarely used for demographic studies because distinguishing the death of the animal (individual mortality) from failure of the tag (mechanical tag failure) has proven difficult. Southern elephant seals present an opportunity to separate tag failure from animal mortality thanks to the availability of large tracking datasets, broad knowledge of demographic rates, and because for these large animals, satellite tags are known not to influence mortality rates. A key rationale for investigating satellite telemetry to estimate mortality as compared to using traditional Capture-Mark-Recapture methods is the potential for obtaining spatially and temporally specific information, particularly while the animals are at sea and largely unobservable. We used satellite tag data from 182 seals from Isles Kerguelen, deployed between 2004 and 2018. Of these, 76 (42%) tags transmitted for the full post-moult foraging trip (max. 265 days for females and max. 305 days for sub-adult males) with the remaining 107 tags (58%) ceasing transmission at sea. We found that contrary to expectations, behavioural choices seem not to influence tag failure rates by mechanical means, rather the signals we detected seemed to align with previously described variation in mortality between groups. There was evidence, albeit limited, for an increase in tag failure for adult females in years with negative Southern Annular Mode (lower Southern Ocean productivity). We speculate that this increase in failure may suggest higher mortality in these years. Also, males using the Kerguelen Plateau had higher tag failure rates than those in the sea-ice zone, perhaps indicative of higher mortality. We suspect that these differences in tag failure rates between groups reflect variation in predator exposure and foraging success. This suggests satellite telemetry could be used to infer mortality events for southern elephant seals while they are at sea. |
|
| |
Programme |
1201 |
|
| |
Campaign |
|
|
| |
Address |
|
|
| |
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 |
2296-7745 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
yes |
|
| |
Call Number |
|
Serial |
8007 |
|
| Permanent link to this record |
