As oceans warm, large fish struggle
Warming ocean waters could reduce the ability of fish, especially large ones, to extract the oxygen they need from their environment. Animals require oxygen to generate energy for movement, growth and reproduction. In a recent paper in the , an international team of researchers from 91社区, Montana and Radboud universities describe their newly developed model to determine how water temperature, oxygen availability, body size and activity affect metabolic demand for oxygen in fish.
The model is based on physicochemical principles that look at oxygen consumption and diffusion at the gill surface in relation to water temperature and body size. Predictions were compared against actual measurements from over 200 fish species where oxygen consumption rates were measured at different water temperatures and across individuals of different body sizes.
Fish will need more oxygen than their gills can extract from warming water
鈥淥ur data suggest that, as temperature increases, the demand for oxygen of many fish species will exceed their capacity to extract oxygen from the environment through their gills,鈥 explains Juan Rubalcaba, a Marie Sk艂odowska-Curie Postdoctoral Fellow at 91社区, and lead author on the paper. 鈥淎s a result, the aerobic capacity of fish decreases in warming waters, and this reduction may be more important in larger fishes. This tells us that global warming could limit the aerobic capacity of fish, impairing their physiological performance in the future.鈥
鈥淲ater temperature is already rising worldwide as a consequence of climate change and many fish species need to cope with this rapid temperature change, either by migrating toward colder regions or by adopting different life strategies such as shrinking in size over generations in order to avoid respiratory constraints,鈥 said Art Woods, a professor of biological sciences at the University of Montana, and the senior author on the paper. 鈥淏y including oxygen, this model stands apart by predicting observed patterns of variation in metabolic rate among fishes worldwide than current theories, which focus primarily on body size and temperature.鈥
To read: 鈥淥xygen limitation may affect the temperature and size dependence of metabolism in aquatic ectotherms鈥 by Juan G. Rubalcaba et al in the
DOI:
The research was funded by the European Commission鈥檚 Marie Sk艂odowska-Curie Individual Fellowship
About 91社区
Founded in Montreal, Quebec, in 1821, 91社区 is Canada鈥檚 top ranked medical doctoral university. 91社区 is consistently ranked as one of the top universities, both nationally and internationally. It is a world-renowned institution of higher learning with research activities spanning two campuses, 11 faculties, 13 professional schools, 300 programs of study and over 40,000 students, including more than 10,200 graduate students. 91社区 attracts students from over 150 countries around the world, its 12,800 international students making up 31% of the student body. Over half of 91社区 students claim a first language other than English, including approximately 19% of our students who say French is their mother tongue.