Notes
Additional data owners: Hutton's Shearwater Trust and Puhi Peaks
Methods for calculating positions from GLS data (analysed by Simon Lamb):
GLS data was processed using the probGLS package in R (Merkel et al., 2016), other packages used are specified below
GLS devices used: BAS Mk-14 geolocators (British Antarctic Survey, Cambridge, UK).
To determine appropriate values for the parameters (mean, standard deviation and maximum value) of: ‘speed.dry’ and ‘speed.wet’ we used GPS-derived velocities of Hutton shearwaters using a maximum value of 2.5 m s-1 as an appropriate cut-off for maximum wet speeds. Wet: mean 0.3911598 ± 0.4747255 sd (max, 2.473817), dry: mean 8.0356733 ± 3.1140281 (max, 16.864860)
Model parameters: Values used
particle.number = 1,000
Iteration.number = 100
sensor = As specified for each bird using the function: probGLS::sst_deduction(datetime, temp = temperature data, temp.range = c(-2,40)) #mean wet temperature
tagging.date = As specified for each bird
retrieval date = As specified for each bird
act = As specified for each bird
trn = As specified for each bird using the below function to interactively determine twilights
#BAStag::preprocessLight(light data,
# threshold = 2.5, #default for open marine open environments
# offset = 10,
# lmax = 20,
# gr.Device = "default")
#Then using the function TwGeos::export2GeoLight(trn file) to get into appropriate format for probGLS
NOAA.OI.location = File path of folder containing environmental data from NOAA (Reynolds et al 2007), data sets required per each year the tracking covers: mean daily ice cover, land mask, mean daily sea surface temperature, mean daily sea surface temperature error
Available from: https://www.esrl.noaa.gov/psd/data/gridded/data.noaa.oisst.v2.highres.html
tagging.location = c(173.61, -42.24) #Kowhai Colony
sunrise.sd = twilight_error_estimation(shape = 2.49, scale = 0.94, delay = 0)
sunset.sd = twilight_error_estimation(shape = 2.49, scale = 0.94, delay = 0)
range.solar = c(-7,-1)
speed.dry = c(8.0356733, 3.1140281, 16.864860)
speed.wet = c(0.3911598, 0.4747255 , 2.473817)
sst.sd = 0.5 #as specified in manual
max.sst.diff = 3
ice.conc.cutoff = 0 #0% of ice expected in this bird’s range
boundary.box = c(-180, 180,-50,-5),
med.sea FALSE
black.sea FALSE
Baltic.sea FALSE
Caspian.sea FALSE
east.west.comp FALSE
wetdry.resolution 3 # 3 second resolution as specified in manual