Effects of temperature and oxygen availability on blood parameters of Hallobatrachus dactylopterus

JUAN MANUEL MOLINA; PEDRO GUERREIRO; ANDREAS KUNZMANN

Bremen

Conferencia; ZMT Annual Conference (ZAC2); 2021

ZMT

Temperature and oxygen are two of the most dynamic and influential physical drivers for marine animals. Unsurprisingly, climate change exerts most of its deleterious effects on the biota by changing these two drivers. We simulated climate change scenarios, to see what were the effects of high temperature, hypoxia and a combination of both on the blood parameters of Hallobatrachus dactylopterus, as well as a condition index. The two environmental drivers studied showed effects on some of the blood parameters of this species over the course of 30 days of exposure. The most affected parameter was the hematocrit, which increased significantly in hypoxic conditions. Hemoglobin concentration was unaffected by our treatments. Red blood cell counts were higher in high temperature, but oxygen levels showed no effects on this parameter. Blood pH was significantly lower in the high temperature normoxic scenario in comparison to all other treatments. These changes seem to have negatively impacted the condition of the fish, as individuals on the high temperature conditions exhibited much lower condition index values.