Data from: Optimization of swim depth across diverse taxa during horizontal travel
Data files
Nov 26, 2024 version files 36.69 MB
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2022_Cm_229845_track_dates.txt
435 B
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2022_Cm_229846_track_dates.txt
814 B
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2022_Cm_229847_track_dates.txt
1.22 KB
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2022_Cm_229848_track_dates.txt
1.29 KB
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2022_Cm_229849_track_dates.txt
1.44 KB
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2022_Cm_229850_track_dates.txt
586 B
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229845_Behavior.csv
487.84 KB
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229845FastGPS.txt
64.50 KB
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229846_Behavior.csv
629.55 KB
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229846FastGPS.txt
97.53 KB
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229847_Behavior.csv
607.18 KB
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229847FastGPS.txt
74.26 KB
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229848_Behavior.csv
319.39 KB
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229848FastGPS.txt
65.91 KB
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229849_Behavior.csv
463.44 KB
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229849FastGPS.txt
91.54 KB
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229850_Behavior.csv
408.49 KB
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229850FastGPS.txt
90.06 KB
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6x2022Cm_all_dives.txt
1.69 MB
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6x2022Cm_all_surface.txt
1.57 MB
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6x2022Cm_depthuse_per_depth_pelagic.txt
1.22 KB
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6x2022Cm_depthuse_per_stage.txt
829 B
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All_LP_ten_min_travel_depths.csv
462.14 KB
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Cc_T1_accelerometry_shallowdives.txt
979.70 KB
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Cc_T1_depth_1_8pm.txt
1.21 MB
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Cc_T1_diveStats_thr02.csv
216.54 KB
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Cc_T2_accelerometry_shallowdives.txt
1.11 MB
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Cc_T2_depth_1_8pm.txt
1.20 MB
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Cc_T2_diveStats_thr02.csv
302.18 KB
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Cc_T3_accelerometry_shallowdives.txt
888.03 KB
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Cc_T3_depth_1_8pm.txt
1.10 MB
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Cc_T3_diveStats_thr02.csv
144.87 KB
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Cc_T4_accelerometry_shallowdives.txt
996.18 KB
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Cc_T4_depth_1_8pm.txt
1.22 MB
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Cc_T4_diveStats_thr02.csv
45.70 KB
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G3004MP4_S1_accelerometry_commute.csv
1.75 MB
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G3004MP4_S1_depth_commute.csv
348.90 KB
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G3004MP4_S1_diveStats_thr005.csv
43.84 KB
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G3004MP4_S1_gps.csv
13.91 KB
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G3012MP15_S1_accelerometry_commute.csv
1.76 MB
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G3012MP15_S1_depth_commute.csv
295.77 KB
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G3012MP15_S1_diveStats_thr005.csv
37.76 KB
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G3012MP15_S1_gps.csv
71.96 KB
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G3013FP4_S1_accelerometry_commute.csv
1.74 MB
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G3013FP4_S1_depth_commute.csv
304.60 KB
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G3013FP4_S1_diveStats_thr005.csv
51.25 KB
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G3013FP4_S1_gps.csv
27.56 KB
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G3048FP12_S1_accelerometry_commute.csv
1.77 MB
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G3048FP12_S1_depth_commute.csv
369.37 KB
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G3048FP12_S1_diveStats_thr005.csv
45.86 KB
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G3048FP12_S1_gps.csv
40.13 KB
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G3059FP16_S1_accelerometry_commute.csv
1.76 MB
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G3059FP16_S1_depth_commute.csv
465.54 KB
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G3059FP16_S1_diveStats_thr005.csv
20.31 KB
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G3059FP16_S1_gps.csv
54.16 KB
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G3065FP2_S1_accelerometry_commute.csv
1.74 MB
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G3065FP2_S1_depth_commute.csv
675.74 KB
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G3065FP2_S1_diveStats_thr005.csv
32.71 KB
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G3065FP2_S1_gps.csv
105.11 KB
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G3091MP2_S1_accelerometry_commute.csv
1.74 MB
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G3091MP2_S1_depth_commute.csv
380.76 KB
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G3091MP2_S1_diveStats_thr005.csv
41.92 KB
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G3091MP2_S1_gps.csv
75.94 KB
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G3115FP15_S1_accelerometry_commute.csv
1.76 MB
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G3115FP15_S1_depth_commute.csv
530.88 KB
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G3115FP15_S1_diveStats_thr005.csv
41.80 KB
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G3115FP15_S1_gps.csv
78.47 KB
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G4021MP15_S1_accelerometry_commute.csv
1.76 MB
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G4021MP15_S1_depth_commute.csv
87.91 KB
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G4021MP15_S1_diveStats_thr005.csv
25.17 KB
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G4021MP15_S1_gps.csv
91.69 KB
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README.md
8.29 KB
Abstract
Semi-aquatic taxa, including humans, often swim at the air-water interface where they waste energy generating surface waves. For marine animals, theory predicts the most cost-efficient depth-use pattern for migrating, air-breathing species that do not feed in transit is to travel at around 2–3 times the depth of their body diameter, to minimise vertical distance travelled whilst avoiding wave drag close to the surface. This has rarely been examined, however, due to depth measurement resolution issues at the surface. Using satellite-relayed data for green turtles (Chelonia mydas), high-resolution depth-accelerometry and video data for little penguins (Eudyptula minor) and loggerhead turtles (Caretta caretta), and literature data for further sea turtle, penguin and whale species, we show that near-surface swimming is likely used broadly across non-foraging diving animals to minimise the cost of transport.
README
ReadMe file for data associated with the paper 'Optimization of swim depth across diverse taxa during horizontal travel'
K. L. Stokes, N. Esteban, P. Casale, A. Chiaradia, Y. Kaska, A. Kato, P. Luschi, Y. Ropert-Coudert, H. J. Stokes, G. C. Hays
https://doi.org/10.5061/dryad.rn8pk0pks
The below lists files containing animal tracking data from the above publication
For dive summary data and comparative literature data see Tables S1–S3 in supplementary materials
'NA' indicates data is not relevant for that cell
1. Green turtles (Chelonia mydas)
6x2022Cm_all_dives.txt
PTT: identifies the individual turtle
What: "Dive" - each row is an individual dive >= 5 m depth
Number: "1" - the number of dives detailed in the current row
Shape: "Square", "V" or "U" - describes the shape of the dive according to definition set by Wildlife Computers
Date: year/month/day (UTC)
Time: hours:minutes:seconds (UTC)
AveLat: the average latitude calculated for that date from the Fastloc-GPS data for that turtle
AveLon: the average longitude calculated for that date from the Fastloc-GPS data for that turtle
HoursAhead: time difference between tag recorded time (UTC) and local time, in hours
MinAhead: time difference between tag recorded time (UTC) and local time, in minutes
LocalDate: converted from UTC time and date based on longitude
LocalTime: converted from UTC time and date based on longitude
Depth: depth reading (m)
Duration: duration of that dive (s)
Stage: "premig" (pre-migratory), "pelagic" (pelagic migratory), "bank" (crossing a submerged bank), "coastalmig" (coastal migratory) or "fg" (foraging ground) - the stage of migration according to the corresponding GPS data
DN: "D", "N" or "C" for diurnal, nocturnal or crepuscular based on timings defined in the above publication
Includes all six green turtles
6x2022Cm_all_surface.txt
Columns as above, 'What' and 'Number' replaced by 'Surface' and 'Deep'
Surface: time spent between 0 and 1 m depth (s)
Deep: time spent between 1 and 5 m depth (s)
Includes all six green turtles
NB Depth categories 0–1 m and 1–5 m were collapsed owing to sensor resolution (0.5 m) and accuracy (1.01 m)
6x2022Cm_depthuse_per_depth_pelagic.txt
Summarises the percentage of time spent within each depth bracket diurnally (Dpc) and nocturnally (Npc)
Dhours and Nhours list the number of hours spent within each depth bracket diurnally (Dhours) and nocturnally (Nhours)
Includes all six green turtles during the pelagic stage only
Depths given in m
6x2022Cm_depthuse_per_stage.txt
Summarises the percentage of time spent within the two depth brackets 0-5 m and 5+ m, diurnally (Dpc) and nocturnally (Npc)
for each stage (pre-migratory, pelagic migratory, coastal migratory, foraging ground/post-migratory)
for all six turtles
Dhours and Nhours list the number of hours spent within each depth bracket diurnally (Dhours) and nocturnally (Nhours)
Depths given in m
2022_Cm_229845_track_dates.txt
(and files for 229846–229850)
These files summarise the dates used to divide the track into the various stages (pre-migratory, pelagic migratory, coastal migratory, post-migratory)
Mig_start: date of departure from nesting region; track before this date is pre-migratory
Fg_start: date the turtle switched from directed movement to sharp turning angles within a final destination (foraging ground); track after this date is post-migratory
Further categories divide the migration into pelagic, coastal and 'bank' if crossing a submerged bank
AveLat and AveLon: average per day, used to calculate the time difference from UTC
LocalDate and LocalTime: converted time and date based on longitude
229845-Behavior.csv
(and files for 229846-229850)
Raw depth tracking files from Wildlife Computers
Dives and surface periods are quantified in terms of depth and duration
See 'all_dives' and 'all_surface' files above for column descriptions and dive classification rules
229845FastGPS.txt
(and files for 229846-229850)
Unfiltered Fastloc-GPS data for each turtle for the duration of tracking
Location estimates are given in Latitude/Longitude
Number of satellites indicates the quality (error class) of each location estimate
HauledOut: whether or not the logger had sufficient 'dry' readings in a row to be classified as on land
2. Loggerhead turtles - files start with 'Cc' for Caretta caretta
Cc_T1_depth_1_8pm.txt
Cc_T2_depth_1_8pm.txt
Cc_T3_depth_1_8pm.txt
Cc_T4_depth_1_8pm.txt
Depth files for the sampling period (1–8 pm on day of release, sampling rate 1 s)
ID: identifies the individual turtle
Depth: depth reading (m)
Surface: minimum depth reading per half hour to be used for zero offset correction
DepthAdj: adjusted depth value after zero offset correction
Date: year-month-day (local time)
Time: hours:minutes:seconds (local time)
Cc_T1_diveStats_thr02.csv
(and files for T2, T3, T4)
Output file from diveMove (R package), applied to depth files above using a dive threshold of 0.2 m
Summarises all dives between 1 and 8 pm on day of release
Each row is an individual dive
Includes travel dives and deep dives
Columns 'divetim' and 'bottdep.mean' are dive duration and mean bottom depth of dive
Descriptions for other columns can be found in the 'diveMove' documentation
Means given in table S1 are for travel dives only (excluding n=2–8 'deep' dives > 5 m)
Cc_T1_accelerometry_shallowdives.txt
(and files for T2, T3, T4)
Accelerometry files for a typical period of travel dives (sampling rate 10 Hz)
Date: year-month-day (local time)
Time: hours:minutes:seconds (local time)
Depth: depth reading (m)
accX, accY, accZ: raw accelerometry values (g) in the surge, sway and heave axes
DepthAdj: adjusted depth reading after zero offset correction
3. Little penguins
All_LP_ten_min_commute_depths.csv
Summary depth file including ten minutes of commute diving per little penguin (sampling rate 1 s)
TagID: identifies the individual little penguin
Pressure: raw pressure reading (mbar)
Date: day/month/year (UTC)
Time: hours:minutes:seconds (UTC)
Depth_m: converted depth value from pressure reading (m)
xxx_gps.csv
(where xxx is the identification code for each individual little penguin)
Unfiltered GPS data for the duration of a single foraging trip per penguin
Location data are given in the 'location.lat', 'location.lon' columns
The number of satellites used to derive the location (given in 'satellites' column) gives an indication of the quality/error class of that estimate
Date and time are in UTC (local time is + 11 h)
xxx_depth_commute.csv
(where xxx is the identification code for each individual little penguin)
Depth data for the commute period (sampling rate 1 s)
TagID: identifies the individual penguin
Timestamp: identifies the date and time including fractional seconds
X_g, Y_g, Z_g: raw accelerometry values in the surge, sway and heave axes (g)
Pressure: raw pressure values used to derive depth (mbar)
Date: day/month/year (UTC)
Time: hours:minutes:seconds (UTC)
xxx_accelerometry_commute.csv
(where xxx is the identification code for each individual little penguin)
Accelerometry data for the relevant commute period selected for each little penguin (sampling rate 25 Hz)
TagID: identifies the individual penguin
Timestamp: identifies the date and time including fractional seconds
X_g, Y_g, Z_g: raw accelerometry values in the surge, sway and heave axes (g)
Pressure: raw pressure values used to derive depth (mbar)
Date: day/month/year (UTC)
Time: hours:minutes:seconds (UTC)
xxx_diveStats_thr005.csv
(where xxx is the identification code for each individual little penguin)
Output files from diveMove (R package), applied to depth files above using a dive threshold of 0.05 m
Each row is an individual dive
Columns 'divetim' and 'bottdep.mean' are dive duration and mean bottom depth of dive - values used in this analysis
Descriptions for other columns can be found in the 'diveMove' documentation online at diveMove package - RDocumentation
https://www.rdocumentation.org/packages/diveMove/versions/1.6.2
Methods
See methods detailed in 'Optimization of swim depth across diverse taxa during horizontal travel' and Supporting Information.