Association between physiological performance and short temporal changes in habitat utilisation modulated by...

Area of Science:

• Ecology
• Physiology
• Environmental Science

Background:

• Temporal environmental variability impacts organismal behavior and physiology, influencing population and community dynamics.
• Linking ecological changes to environmental drivers is complex, but integrating physiological data can facilitate this connection.

Purpose of the Study:

• To investigate the association between physiological performance and habitat utilization patterns in fish.
• To understand how short-term fluctuations in environmental factors, specifically dissolved oxygen (DO), modulate these patterns.

Main Methods:

• In situ monitoring of fish species with varying habitat use across dissolved oxygen (DO) fluctuations.
• Measurement of metabolic variables including critical oxygen (O_2crit), incipient lethal oxygen (ILO), and oxygen deficit (O_2deficit) using respirometry.
• Analysis of field monitoring data to correlate physiological performance with observed habitat use.

Main Results:

• Physiological performance varied significantly among the four studied fish species (Siganus lineatus, Acanthopagrus pacificus, Heniochus acuminatus, and Chaetodon vagabundus).
• Species with lower O_2crit and better survival capacity below O_2crit (S. lineatus, A. pacificus) were observed in areas with lower DO.
• DO levels frequently dropped below species' critical and lethal thresholds, indicating that short-term avoidance of hypoxic conditions drives habitat use.

Conclusions:

• Organismal physiology provides crucial insights into ecological changes driven by short-term environmental variability.
• Integrating physiological data with ecological data at relevant temporal scales is essential for predicting ecosystem structure and function shifts.
• This approach can help identify ecological patterns often overlooked due to their rapid, short-term nature.