Water temperature modulates social behavior of ornamental cichlid (Pterophyllum scalare) in an artificial system

ABSTRACT

Environmental changes can cause physiological alterations in fish, which may affect some behavioral patterns. We evaluated the effects of water temperature on the aggressive behavior of male freshwater angelfish, Pterophyllum scalare. We subjected pairs to three water temperature conditions: low (23.8 ± 0.8°C), medium (27.9 ± 1.2°C), and high (31.7 ± 1.0°C), with eight repetitions each. We assessed latency to fighting, aggressive interaction frequency, and territorial defense. In low and high temperatures there was a reduction in aggressive behavior exhibitions in comparison to medium temperatures (P < 0.05). As a result, water temperature can influence aggressive motivation and territorial establishment, given that temperatures closer to species optima (27.9 ± 1.2°C) can favor social contests for an Amazonian ornamental cichlid species, P. scalare.

KEYWORDS:

• Aggressiveness
• environmental change
• fish
• social hierarchy

Authors’ contributions

All authors contributed equally to this work.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Ethics statement

All procedures employed in this study were in accordance with Brazilian Council for Animal Experimentation under the protocol number 061/2017, approved by the Ethics Committee for the Use of Animals of UFAM.

Additional information

Funding

This work was supported by the FAPEAM (Fundação de Amparo à Pesquisa do Estado do Amazonas under grant (number 062.00679/2015). MWSR is a recipient of a CAPES personal grant.