DOI: 10.5061/dryad.2rbnzs7vm
title: Data and code from: You shall not pass, the Pacific oxygen minimum zone creates a boundary to shortfin mako shark distribution in the Eastern North Pacific Ocean

description: Shoaling of large oxygen minimum zones (OMZs) that form along eastern
 margins of the world’s oceans can reduce habitat availability for some
 pelagic fishes. Our aim was to test the hypothesis that habitat
 compression caused by shoaling of the Pacific OMZ in tropical regions
 creates a boundary to the southern distribution of shortfin mako sharks
 (Isurus oxyrinchus) in the Eastern North Pacific Ocean.
description: Satellite tagging of shortfin mako sharks captured in long line
 or sportfishing equipment in the northwest Atlantic (2013 - 2020) and
 northeast Pacific (2003-2016) Oceans. Sharks were tagged with fin-mounted
 satellite-linked radio tags (SLRT), and a subset of sharks in the Pacific
 were also tagged with pop-up archival tags (PAT). 
 <strong>Location </strong> Eastern
 North Pacific and Western North Atlantic oceans.
 <strong>Methods </strong> We
 compared environmental conditions between areas used by satellite-tagged
 mako sharks in the Eastern North Pacific, encompassing the world’s largest
 OMZ, to those used in the Western North Atlantic where no OMZ is present.
 In the Pacific we quantified the effects of temperature and dissolved
 oxygen (DO) on depth use and tested if sharks spent less time in areas
 with strong habitat compression over the OMZ than expected by
 chance. <strong>Results</strong>
 The southern distribution of sharks in the Pacific corresponded
 with the apex of OMZ shoaling in the North Equatorial Current. Sharks in
 the Atlantic occupied areas with warm surface temperatures (≥
 26<sup>o</sup>C) more often than the Pacific, and waters with
 these temperatures in the Atlantic had greater DO at depth. Sharks in the
 Pacific reduced time near the surface in warm temperatures and
 consistently avoided depths with low DO and spent less time in areas with
 strong habitat compression than expected by chance.
 <strong>Main Conclusions</strong>
 The combination of warm surface temperatures and shoaling of the
 OMZ creates a soft boundary to mako shark movements in the Eastern North
 Pacific Ocean. The expected expansion of OMZs due to climate change could
 have considerable impact on future distribution of mako sharks and other
 pelagic fish. As such, development of species distribution models to
 predict effects of climate change on pelagic fish distributions should
 incorporate oxygen availability.
description: # Data and code from: You shall not pass; the Pacific oxygen minimum zone
 creates a boundary to shortfin mako shark distribution in the Eastern
 North Pacific Ocean
 [https://doi.org/10.5061/dryad.2rbnzs7vm](https://doi.org/10.5061/dryad.2rbnzs7vm) Satellite tracking data for mako sharks in the Eastern North Pacific and Western North Atlantic Oceans, as well as environmental data and R code for simulating tracks. ## Description of the data and file structure AtlanticArgos.csv; Raw Argos data for mako sharks in the Atlantic, with columns: id = track id date = date and time (UTC) of Argos detections lc = Argos location class (3,2,1,0,A,B) lon = longitude lat = latitude PacificArgos.csv; Raw Argos data for mako sharks in the Pacific, with columns: id = track id date = date and time (UTC) of Argos detections lc = Argos location class (3,2,1,0,A,B) lon = longitude lat = latitude Track_Simulation_Analysis_Code.R = R code for simulating tracks and recreating the analysis of avoidance of the Pacific OMZ Mako_DATA.RData = an R workspace containing data objects including: 12 Monthly Raster Brick objects with SST, Ocean Heat Content, and Dissolved O2 at 100m (JanR, FebR, etc.) Atl.SSM = Data frame of daily SSM location estimates for Atlantic Sharks Pacific.SSM = Data frame of daily SSM location estimates for Pacific Sharks Atl.samples = Data frame of 100 random daily MCMC samples from SSM locations for Atlantic sharks PacFemale.samples = Data frame of 100 random daily MCMC samples from SSM locations for female Pacific sharks PacMale.samples = Data frame of 100 random daily MCMC samples from SSM locations for male Pacific sharks Simulation.Data = Data frame of daily locations and habitat variables for simulated tracks simulation.summary = Data frame of summarized count of days over the Pacific OMZ for real and simulated tracks Pacific_TAD.csv; Time at depth data for make sharks in the Pacific during days with SLRT and PAT available. Columns include: id = shark id PAT_PTT = PAT tag id spot_tt = SLRT id Date = Date B_50 = proportion of time between 0 - 50m B100 = proportion of time &gt;50 - 100m B150 = proportion of time &gt;100 - 150m B200 = proportion of time &gt;150 - 200m B_200 = proportion of time &gt; 200m lon = longitude lat = latitude SST = sea surface temperature (Celsius) DO_depth = Hypoxic boundary depth (m), where dissolved oxygen concentration is 3.0 ml/l ## Code/Software All analyses were run in R v4.2.2