Squat lobster latitudinal life habitat shifts and metabolic response to combined temperature and oxygen conditions in the Humboldt Current System

We examined how a species inhabiting a latitudinal gradient from surface oxygenated warm waters to subsurface severely oxygen-limited cold waters along the continental shelf of the Eastern South Pacific (ESP) is responding to the latitudinal temperature changes of low oxygen isopleths. We combined temperature-oxygen latitudinal sections from World Ocean Database, historical recordings of pelagic/benthic Grimothea monodon occurrence through latitude and conducted laboratory experiments assessing juvenile’s routine and postprandial metabolism at realistic oxygen-temperature conditions. S quat lobsters main habits (pelagic to benthic) were related with temperature at the 2 ml O ₂ L ^− 1 (~ 89 µM) oxygen isopleth. Warm (> 15°C) hypoxic upper oxygen minimum zone (OMZ) impairs G. monodon all time permanence on benthic habitat or restrict it to pelagic habits. The physiological performance of juveniles (main migratory stage) was negatively affected by high temperature-hypoxia interaction. Routine metabolic rates showed a 60% decrease with hypoxia at high temperatures (21°C). Postprandial metabolism (as SDA) was mostly affected at high temperatures and low oxygen. Grimothea monodon can adjust their life habits to a wide range of conditions along the ESP coast maintaining intergenerational capability to shift from one habit to the other, their expansion/restriction in vertical distribution, would allow for maintaining/expanding latitudinal ranges as benthic and pelagic food webs adjust to its availability as key prey item and humans to future fishing grounds.