Dataset: Photobehavior for octopus (‘Octopus bimaculatus’) and squid (‘Doryteuthis opalescens’) paralarvae during exposure to 9 light irradiance levels and 4 oxygen conditions in trials conducted in April of 2019

This dataset gives the results of photobehavior experiments under different oxygen conditions in larvae of the market squid (Doryteuthis opalescens) and two-spot octopus (Octopus bimaculatus). Photobehavior experiments were conducted to determine whether the impairment of visual physiology observed in marine invertebrate larvae (McCormick et al., 2019) is subsequently affecting visual behavior in marine larvae.

Briefly, animals were placed in a 20cmx4cmx5cm clear plexiglass chamber filled with seawater to 16cm inside a light-tight box with an overhead light stimulus. After animals were placed in the chamber, the oxygen and temperature were measured, and then a 15-minute dark adaptation period was started. The experiment consisted of a series of a 10-s light stimulus followed by 3-minute dark period; this was repeated at 9 different irradiance levels (1= lowest, 9= highest; 0.062-2.45 mol photons/m^2/s) and at 4 different oxygen levels. Oxygen levels were selected based on the 3 visual metrics that were calculated to quantify the effects of reduced pO2 on retinal function (McCormick et al., 2019). V90, V50, and V10 were calculated for each individual larva as the oxygen where there was 90%, 50%, and 10% retinal function remaining, in respect to retinal responses in normoxia (surface-ocean oxygen levels). For squid, oxygen levels were 1) Normoxia (21.1 kPa); 2) V50 (12.9 kPa); 3) V10 (6.6 kPa); and 4) Low (4.2 kPa). For octopus, oxygen levels were 1) Normoxia (21.3 kPa); 2) V90 (10.7 kPa); 3) V50 (7.4 kPa); and 4) V10 (5.8 kPa). All experiments were video recorded and analyzed using Noldus EthoVision XT software (version 15).

Oxygen and temperature were measured using a Microx4 (PreSens) oxygen meter and a Pst-7 oxygen optode probe.