southern elephant seal
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This meta data describes the raw output of the SES DEB-IBM built in NetLogo (version 6.0.1, March 2017; available from http://modelingcommons.org/browse/one_model/5348). The raw output consists of .csv files from several model runs. The detailed explanation of the model workings and background are published in Goedegebuure et al. (2018, PLoS ONE; Modelling southern elephant seals Mirounga leonina using an individual-based model coupled with a dynamic energy budget; DOI: 10.1371/journal.pone.0194950). In short: we developed an individual-based model which is coupled with a dynamic energy budget (a DEB-IBM) for southern elephant seals to demonstrate a method for detailed representation of marine mammals. We aimed to develop a model which could i) simulate energy use and life histories, as well as breeding traits of southern elephant seals in an emergent manner, ii) project a stable population over time, and iii) have realistic population dynamics and structure based on emergent life history features (such as age at first breeding, lifespan, fecundity and (yearling) survival). We evaluated the model's ability to represent a stable population over long time periods (> 10 generations), including the sensitivity of the emergent properties to variations in key parameters. The model was developed using life history data of female southern elephant seals from Macquarie Island and follows individuals from birth to death. The information collected in the raw output are the same for the baseline model (stable, and with standard parameters), and the modified models to test for 1) low, and 2) high food availability, 3) low, and 4) high weaning thresholds (energetic level at which pups transition to juveniles), 5) low, and 6) high puberty thresholds (energetic level at which juveniles transition to physically mature adults). As well as recording the parameter values as set in the model, each .csv file records: 1) run number (usually 1-10) 2) step (time step, days) 3) min age at first breeding (years) 4) min age of adult 5) mean age of adult 6) mean age of juvenile 7) max age of individuals 8) max number of pups per female 9) fecundity 10) max size of individuals 11) mean size of adults 12) mean size of juveniles 13) total count of modelled population 14) total count of embryos 15) total count of pups 16) total count of yearlings 17) total count of juveniles (includes yearlings) 18) total count of adults 19) mean food availability of independent individuals (those not reliant on their mother) that are not fasting/moulting 20) carrying capacity (or expected equilibrium) 21) seed NB. NetLogo calls individuals within the model turtles - thus output will mention turtles. Stages are as follows 0 = foetus, 1 = pup, 2 = juvenile, 3 = adult. Status are as follows, 0 = dependent on mother, 1 = fasting, 2 = foraging.
Between 1951-1965 and 1993-1999 newly weaned southern elephant seal pups were captured and permanently marked. Organised re-sight efforts were made to provide longitudinal demographic data for this population. Biological data from individual short-term scientific projects includes information on physical condition for a portion of pups and adult seals.