Social dynamics obscure the effect of temperature on air breathing in Corydoras catfish

Type Article
Date 2020-11
Language English
Author(s) Pineda Mar1, Aragao Isabel1, McKenzie David2, Killen Shaun S.1
Affiliation(s) 1 : Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
2 : MARBEC, Université de Montpellier, CNRS, Ifremer, IRD, 9190 Montpellier, France
Source Journal Of Experimental Biology (0022-0949) (The Company of Biologists), 2020-11 , Vol. 223 , N. 21 , P. jeb222133 (9p.)
DOI 10.1242/jeb.222133
Keyword(s) Air-breathing fish, Environmental stress, Metabolic rate, Oxygen, Social behaviour
Abstract

In some fishes, the ability to breathe air has evolved to overcome constraints in hypoxic environments but comes at a cost of increased predation. To reduce this risk, some species perform group air breathing. Temperature may also affect the frequency of air breathing in fishes, but this topic has received relatively little research attention. This study examined how acclimation temperature and acute exposure to hypoxia affected the air-breathing behaviour of a social catfish, the bronze corydoras Corydoras aeneus, and aimed to determine whether individual oxygen demand influenced the behaviour of entire groups. Groups of seven fish were observed in an arena to measure air-breathing frequency of individuals and consequent group air-breathing behaviour, under three oxygen concentrations (100%, 60% and 20% air saturation) and two acclimation temperatures (25 and 30°C). Intermittent flow respirometry was used to estimate oxygen demand of individuals. Increasingly severe hypoxia increased air breathing at the individual and group levels. Although there were minimal differences in air-breathing frequency among individuals in response to an increase in temperature, the effect of temperature that did exist manifested as an increase in group air-breathing frequency at 30°C. Groups that were more socially cohesive during routine activity took more breaths but, in most cases, air breathing among individuals was not temporally clustered. There was no association between an individual's oxygen demand and its air-breathing frequency in a group. For C. aeneus, although air-breathing frequency is influenced by hypoxia, behavioural variation among groups could explain the small overall effect of temperature on group air-breathing frequency.

Full Text
File Pages Size Access
Publisher's official version 9 616 KB Open access
Top of the page