DOI: 10.5061/dryad.mw6m90624
title: Ontogeny of movement patterns in naïve grey seal pups inhabiting a complex continental shelf ecosystem

description: Most vertebrate offspring must transition from the relative security of
 parental care (nutrition and protection) to independent foraging.
 Offspring face many challenges during this critical period, particularly
 in species where parental care ends at weaning, such as the grey seal
 (Halichoerus grypus). We studied the development of movement behaviour in
 naïve grey seal pups from their first trips to sea to about five months of
 age. Twenty-five (12 males and 13 females) newly-weaned pups were fitted
 with satellite-linked GPS tags on Sable Island, Nova Scotia, Canada in
 January 2016. The influence of fixed effects (pup size, sex, week) and the
 random effect of pup identity on trip characteristics were examined.
 Movement behaviour was analyzed using a move persistence mixed-effects
 model. Habitat use was highly variable among individuals and covered much
 of the geographic distribution of the population. Unlike older juveniles,
 subadults, and adults in this population, most naïve pups used multiple
 haulout sites to begin and end trips. There was little evidence of
 area-restricted search behaviour during trips, suggesting that naïve pups
 were using an opportunistic foraging tactic that may result in more
 variable foraging success than that of older, experienced animals. Naïve
 pups made longer trips with longer haulout durations between them than
 observed for older greys seals. Males and females differed in some trip
 characteristics, but sex effects were small over the first few months of
 life. Offspring size at weaning was not a useful predictor of trip
 characteristics. Move persistence of grey seal pups was initially high and
 then decreased over time as individuals gained experience. Both intrinsic
 and extrinsic factors were influential on the movements of grey seal pups.
 Greater body length at weaning, longer duration spent on shore after
 weaning, shallower water column depth, and farther distance from shore
 were all associated with lower move persistence. Female grey seal pups had
 lower move persistence than males. Overall, the movements of naïve grey
 seal pups during the first few months of life were characterized by
 extensive exploration, but move persistence decreased over time suggesting
 they may be using an exploration-refinement foraging tactic.
description: ## DFO Sable Island Grey Seal Pup Project Twenty-five newly-weaned pups
 were fitted with satellite-linked GPS tags on Sable Island, Nova Scotia,
 Canada in January 2016. We studied the development of movement behaviour
 in naïve grey seal pups from their first trips to sea to about five months
 of age. We explored the influence of intrinsic factors on the trip
 characteristics and move persistence of grey seal pups and how their
 movement behaviour changed over time. ## Description of the data and file
 structure The data for this project includes two files: (1)
 2016PupDeployments-PupData.csv This file includes the biometric data
 collected on grey seal pups selected for inclusion in this study with the
 following columns: DeployID - unique identifier for each individual grey
 seal included in the study PTTID - Argos Platform Transmission Terminal
 identifier, which is a unique number identifying each Mk10-AF Fastloc GPS
 tag SerialNo - serial number for each Mk10-AF Fastloc GPS tag Cohort -
 year grey seal pups were born where 2016 corresponds to December
 2015/January 2016 Sex - individual sex where male = 1 and female = 2
 WeanDate - the date each grey seal pup was weaned WeighDate - the date
 each grey seal pup was weighed WeanWeight - the mass (kg) of each grey
 seal on the WeighDate StdLength - the standard length (cm) of each grey
 seal at the time of instrumentation TagDeployment - date the Mk10-AF
 Fastloc GPS was instrumented on each grey seal pup Comments - any
 additional comments regarding data transmission (2)
 2016PupDeployments-Locations.csv This file includes the Fastloc GPS and
 Argos locations collected by grey seal pups instrumented with Mk10-AF
 Fastloc GPS tags (www.wildlifecomputers.com) with the following columns:
 DeployID - unique identifier for each individual grey seal included in the
 study PTTID - Argos Platform Transmission Terminal identifier, which is a
 unique number identifying each Mk10-AF Fastloc GPS tag Instr - Wildlife
 Computers instrument family Date - date and time (AST) of each location
 Type - type of location, either GPS (Fastloc GPS) or Argos Quality - class
 of location generated by Argos for the satellite pass containing this
 message - values in ascending order of quality are "Z",
 "B", "A", "0", "1", "2",
 "3" Latitude - latitude of the location Longitude - longitude of
 the location ## Sharing/Access information This project was financially
 supported by the Department of Fisheries and Oceans, Canada and The Ocean
 Tracking Network, Dalhousie University, Halifax, Nova Scotia. All sampling
 protocols were conducted in accordance with the requirements of the
 Canadian Council on Animal Care and were approved by Fisheries and Oceans
 Canada's Maritime Region Animal Care Committee (protocol number
 15-27) and Dalhousie University’s Committee on Laboratory Animals
 (protocol number 15-115). Work was undertaken under the Parks Canada
 Agency Research and Collection Permit SINP-2012-12974.