Demography, ecology and behaviour of southern elephant seals of Sea Lion Island, Falkland Islands (1995-2019)

The dataseries on southern elephant seals (Mirounga leonina) of Sea Lion Island (Falkland Islands) is based on data collected from 1995 to present. The general goal of this long term research project is the study of breeding and survival strategies of individual seals, by marking seals at birth and following up them along their whole lifetime, thanks to the high breeding site fidelity of these seals. The study of lifetime individual strategies can greatly help in elucidating some core aspects of the theory of evolution by natural and sexual selection. The study has a special focus on behavioural strategies and tactics used to compete, mate, and breed, but we are using a multi-factorial approach, and we are collecting data on the seal structural phenotype (age, size and morphology), on the effect of the spatial and social structure of the population on individual behaviour, on the effects of hormones and physiology at large on behaviour; and on the genetic correlates of the social system. On the applied side, we are producing estimates of population size and trend, vital statistics and life tables, analysis and forecast of population viability, and study of habitat selection and usage. Along the years we produced a rather large amount of articles on different aspects of seal biology, ranging from demography to vocal communication. Further information is available on the research group website,

Data and Resources

Additional Info

Field Value
Last Updated December 21, 2020, 10:00 (PST)
Created January 30, 2020, 05:20 (PST)
Region Falkland Islands
Language eng
Topic Category Biota; flora and/or fauna in natural environment
Temporal Extent Start 1995-01-01
Temporal Extent End 2019-12-31
Dataset Reference Date 2019
Lineage Various methologies have been used for colleting a large number of different data types. Briefly, tags (Dalton Jumbo and Caisley Primaflex tags) are deployed for long-term marking of seals (mark-resight study); hair dye marks are used to recognize seals from the distance (behaviour study); count and identification sessions are carried out daily (estimation of population trend); mapping of individuals is used to study movements, site fidelity, and population spatial structure; data on breeding events (e.g., births) is collected to to study variation in timing of breeding; observation of elephant seal bahaviour is used to study social system, communication, mating tactics and breeding strategies; weighing and measurement of pups are carried out to study maternal investment and to assess female access to resources; skin and blood samples are taken for genetic studies, to assess stress, and to study pathogens (population health study); environmental data is collected using dataloggers to study the relationship between microclimate and elephant seals behaviour. Spatial data is collected by GPS and used to map the coastline, the topography of the breeding areas, and the profile of harems. GPS tracks of each operator are used to estimate the effective time spent in the field, and the km walked in the study areas (measures of effort used to standardize the collected data). Accurate positioning of individual females inside harems is collected using a 3D laser positioning system (Laser Locator, Leica, +/- 1m precision). This system allows the collection of spatial data together with behavioural data without disturbing the seals. More information on the project, and all the published papers, are available on the research project website ( For access to data please contact the data owner.
West Longitude -59.1519
South Latitude -52.4486
East Longitude -59.0364
North Latitude -52.4205
Spatial Reference System WGS84
Responsible Organisation Name Hidden (personal data protection)
Contact Mail Address Hidden (personal data protection)
Responsible Party Role Hidden (personal data protection)
Access Limitations Restricted, send data request to data owner
Use Constraints Restricted, but open subject to limitations and prior agreement with responsible organisation. Copyright must be cited
Resource Reference Copyright ESRG 1995-present - All Rights Reserved. Please contact ESRG before citing unpublished reports.
Data Format csv, pdf
Update Frequency annually
Accuracy mapping with GPS (e.g. daily mapping of males): 5 m. mapping of topography and harem profiles is submetric to decimetric. position of individual females with Laser Locator is between 0.5 and 1 m
Resource Type Dataseries
Original Title Hidden (internal use only)
Metadata Date 2019-04-03
Metadata Point of Contact
Contact Consent Contact details hidden
Unique Resource ID FK-ESRG-169

Dataset extent

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