DOI: 10.5061/dryad.qv9s4mwnp
title: Blood oxygen transport and depletion in diving emperor penguins

description: Oxygen store management underlies dive performance and is dependent on the
 slow heart rate and peripheral vasoconstriction of the dive response to
 control tissue blood flow and oxygen uptake. Prior research has revealed
 two major patterns of muscle myoglobin saturation profiles during dives of
 emperor penguins. In Type A dives, myoglobin desaturated rapidly,
 consistent with minimal muscle blood flow, and low tissue oxygen uptake.
 Type B dives, with fluctuating and slower declines in myoglobin
 saturation, were consistent with variable tissue blood flow patterns and
 tissue oxygen uptake during dives. We examined arterial and venous blood
 oxygen profiles to evaluate blood oxygen extraction and found two primary
 patterns of venous hemoglobin desaturation that complemented corresponding
 myoglobin saturation profiles. Type A dives had venous saturations that a)
 increased or plateaued for most of the dive and that only declined during
 the latter stages of ascent, b) often became arterialized (arterio-venous
 (a-v) shunting). In Type B dives, variable but progressive venous
 hemoglobin desaturation profiles were interrupted by inflections in the
 profile that were consistent with fluctuating tissue blood flows and
 oxygen uptake. End-of-dive saturations of arterial and Type A venous dives
 were not significantly different, but did differ from those of Type B
 venous dives. These findings provide further support that the dive
 response of emperor penguins is a spectrum of cardiac and vascular
 components (including a-v shunting) that are dependent on the nature and
 demands of a given dive and even of a given segment of a dive.
description: Data were collected with backpack recorders on diving emperor
 penguins in 2001-2008, and downloaded to computers for analysis.
description: # Blood oxygen transport and depletion in diving emperor penguins
 Data were collected with
 backpack recorders on diving emperor penguins, and then downloaded to
 computers for processing. Research was conducted at a sea ice camp in
 McMurdo Sound, Antarctica in 2001-2008  (see this article and related
 citations for details of procedures, data collection, and prior analyses
 of data). There were two types of recorders: an oxygen recorder and a
 depth recorder.  The recorders stored time (mm dd yyyy hh:mm:ss) and depth
 (meters), and time (mm dd yyyy hh:mm:ss) and the partial pressure of
 oxygen (PO2, mm Hg). These data allowed construction of oxygen and depth
 profiles versus time. A given bird had either an arterial or venous oxygen
 electrode (one electrode per bird).  As explained in the paper, the PO2
 was converted to hemoglobin saturation (%) with use of the emperor penguin
 O2-hemoglobin dissociation curve from Meir and Ponganis, 2009. In this
 paper, the profiles were sorted into three groups according to the type of
 hemoglobin saturation profile: arterial, Type A venous, and Type B
 venous. Criteria for Type A and Type B venous saturation profiles are
 described in the text. ## Description of the data and file structure There
 are two files.  * Saturation Profile Groups - ID & Dive
 Parameters.xlsx * Dive depth & Hb saturation data.xlsx There are two
 .xlsx files in the directory. The first file (**Saturation Profile Groups
 - ID & Dive Parameters.xlsx**) summarizes oxygen profile and dive
 characteristics for all dives in the study. The summary for each group
 (arterial, Type A venous, Type B venous) included Bird ID, Dive ID (the
 number assigned to a given dive), dive duration (minutes), maximum dive
 depth (meters), start time and end time (time is in hh:mm:ss). The second
 file (**Dive depth & Hb saturation data.xlsx**) contains serial
 collections of time, blood partial pressure of oxygen (PO2 in mm Hg),
 hemoglobin saturation (%, calculated with the pH 7.5 oxygen-hemoglobin
 dissociation curve) and depth (meters) for each bird. Blood oxygen and
 depth data are on a single worksheet for each bird in that file. On each
 worksheet, the Bird ID and a brief summary of the data are given at the
 top of the page. Time, PO2 and hemoglobin saturation are listed in the
 first set of columns; time and depth are presented in the second set of
 columns.  Time is either in date/time (M D YYYY h:mm:ss.000) or in time
 (in hh:mm:ss.000) depending upon the bird.