DOI: 10.5061/dryad.zpc866t7f
title: Macquarie Island southern elephant seal capture-mark-recapture data

description: The Southern Ocean has been disproportionately affected by climate change
 and is therefore an ideal place to study the influence of changing
 environmental conditions on ecosystems. Changes in the demography of
 predator populations are indicators of broader shifts in food-web
 structure, but long-term data are required to study these effects.
 Southern elephant seals (Mirounga leonina) from Macquarie Island have
 consistently decreased in population size while all other major
 populations across the Southern Ocean have recently stabilised or are
 increasing. Two long-term mark-recapture studies (1956-1967 and 1993-2009)
 have monitored this population, which provides an opportunity to
 investigate demographic performance over a range of climatic conditions.
 This provides insights on individual vital rates of known-age seals from
 Macquarie Island over extensively long timeseries.
description: Between 1951–1965 and 1993–1999 weaned Southern Elephant Seals
 were captured and marked permanently by hot iron branding. Seals were
 recorded in regular re-sights varying from daily isthmus searches during
 the breeding season to ad-hoc sightings outside of active monitoring.
 Biological data from individual short-term scientific projects include
 information on the physical condition for a sub-set of pups and adult
 seals.
description: Comma separated value (CSV) file able to be accessed through
 Microsoft Excel, R Studio or other analytical software
description: # README *** Macquarie Island southern elephant seal
 capture-mark-recapture history Author: Sophia Volzke, University of
 Tasmania Two long-term mark-recapture studies (1956-1967 and 1993-2009)
 have monitored the Macquarie Island breeding population of southern
 elephant seals (Mirounga leonina). These records provide an opportunity to
 investigate individual vital rates of known-age seals over extensively
 long timeseries. ## Description of the data and file structure Between
 1951-1965 and 1993-1999 weaned Southern Elephant Seals were captured and
 marked permanently by hot iron branding. Seals were recorded in regular
 re-sights varying from daily isthmus searches during the breeding season
 to ad-hoc sightings outside of active monitoring. Biological data from
 individual short-term scientific projects includes information on physical
 condition for a sub-set of pups and adult seals. Data includes a header
 row with descriptions for columns: * SIGHTING\_ID: Uniquely assigned
 number of each sighting (numeric) * WEIGHT: Weight of the individual (in
 kg) * SEX\_ON\_SIGHTING: Sex assigned during re-sighting (M Male or F
 Female) * SEAL\_TAGS\_ON\_ANIMAL: Number of flipper tags on animal (0, 1,
 2 or U - unknown) * MASTER\_SEX\_CHECKED: Sex of animal as assigned upon
 tagging and checked across adult sighting records (M Male; F Female; U
 Unknown) * SEAL\_ID: Unique identifier of animal, as assigned by brand
 and/or tag ID code (numeric) * MASTER\_TAG\_TYPE: Roto Flipper Tags or
 Branding method used for tagging (T Tags; B Branding; BT both tags and
 brands) * MOULT\_ID: State of moult in thirds (1/3 &lt; one third
 moulted, 2/3 &lt; two thirds moulted, 3/3 = between 2/3 and 3/3, and
 5/3 for complete moult. 99 if not moulting) * MODIFIED\_BY: Name of
 researcher * ENTERED\_BY: Name of researcher * DATE\_OBSERVED: Observation
 date format DD/MM/YYYY * DATE\_MODIFIED: Record modified date format
 DD/MM/YYYY * DATE\_ENTERED: Entered date format DD/MM/YYYY * COMMENTS:
 Text * SEAL\_STATUS\_ID: Number indicating breeding status upon sighting
 (01 McPherson; 02 Harem Cow with Pup; 03 Dominant Bull; 04 Assistant
 Beachmaster; 05 Challenger; 06 Bachelor Gay; 07 Pregnant Cow; 08 Moulting;
 09 Midyear haul-out; 10 Post-partum Cow; 11 End-lactation Cow; 12 Cow with
 dead pup; 13 Cow who has abandoned pup; 14 Cow with adopted pup; 15 Cow
 who has aborted pup; 16 Copulating Cow; 99 Unknown) * AGE\_CLASS\_ID:
 Number indicating age class upon sighting (01 Black Pup; 02 Weaned Pup; 03
 Suckling Pup; 04 Post-wean Pup; 05 Abandoned pup; 10 Underyearling; 20
 Yearling; 30 Subadult; 40 Adult; 50 Dead; 99 Unknown) ## Sharing/Access
 information This dataset is publicly available and has been kept updated
 as seals are sighted and this population continues to be monitored
 annually. Links to other publicly accessible locations of the data: *
 Australian Antarctic Data centre: (1950 to 1965)
 https://data.aad.gov.au/metadata/records/AADC-00101 (1985 Onwards)
 https://data.aad.gov.au/metadata/records/AADC-00102 ## Code/Software Comma
 separated value (CSV) file able to be accessed through Microsoft Excel, R
 Studio or other analytical software.