We are excited to announce the publication of our latest research article, "Exploring freshwater soundscapes of tropical marshland habitats in Southeast Asia: insights into auditory sensory adaptation of wild Siamese fighting fish Betta splendens," in PeerJ.
The Siamese fighting fish (Betta splendens), renowned in the ornamental fish industry and as a model for genetic and behavioral studies, thrives in the tranquil freshwater marshlands of Southeast Asia. Our study delved into the natural soundscapes of these habitats in Chiang Rai province, Thailand, to understand how these environments influence the auditory adaptations of wild B. splendens.
Key Findings
Habitat Characteristics: The studied marshlands are characterized by low dissolved oxygen levels and dense vegetation, providing a unique acoustic environment.
Soundscape Analysis: These habitats are relatively quiet, with sound pressure levels ranging from 102 to 105 dB re 1 µPa, and most acoustic energy concentrated below 1,000 Hz. The recordings captured a variety of biological sounds, predominantly from insects and potential fish vocalizations.
Auditory Sensitivity: Using auditory evoked potential recordings, we determined that B. splendens have optimal hearing within the 100–400 Hz frequency range. Notably, males exhibited greater sensitivity than females at 400 and 600 Hz.
Implications
Our findings suggest that B. splendens are finely tuned to low-frequency sounds prevalent in their natural habitats, making them potentially vulnerable to anthropogenic noise pollution. This research underscores the importance of preserving the quietude of lentic freshwater ecosystems to maintain the auditory health and ecological balance of species like the Siamese fighting fish.
For a comprehensive understanding of our study, we invite you to read the full article here:
Ramos A., Gonçalves D., Vasconcelos R.O. (2025). Exploring freshwater soundscapes of tropical marshland habitats in Southeast Asia: insights into auditory sensory adaptation of wild Siamese fighting fish Betta splendens. PeerJ 13:e18491 https://doi.org/10.7717/peerj.18491
This research was a collaborative effort among scientists from the Institute of Science and Environment at the University of Saint Joseph, Macao, MARE–Marine and Environmental Sciences Centre at the University of Lisbon, and the Department of Life Sciences at Lusófona University, Lisbon. We extend our gratitude to the funding bodies and local communities in Thailand who supported this research.
Stay tuned to our website for more updates on our ongoing research.