A different approach to identifying thermal parameters for invasive species

Area of Science:

• Entomology
• Invasive Species Biology
• Ecological Physiology

Background:

• The brown marmorated stink bug (Halyomorpha halys) is an invasive agricultural pest in the eastern United States.
• Environmental temperature is a key factor in the establishment and spread of invasive species.
• Understanding the metabolic response to temperature across all life stages is crucial for predicting invasive potential.

Purpose of the Study:

• To investigate the metabolic response of all life stages of Halyomorpha halys to varying temperatures.
• To identify the most temperature-sensitive life stage of H. halys.
• To assess the utility of differential scanning calorimetry in predicting invasive species establishment.

Main Methods:

• Differential scanning calorimetry (DSC) was employed to analyze the metabolic activity of H. halys across different temperatures.
• Isothermal and scanning calorimetric experiments were conducted on all life stages, including eggs, nymphs (instars), and adults.
• Calorimetric data were used to determine lower, optimal, and upper developmental temperatures.

Main Results:

• The third instar nymph was identified as the most thermoresponsive life stage of H. halys.
• Eggs and fifth instar nymphs exhibited the least thermoresponsiveness.
• Third instar nymphs demonstrated a broader range of thermoresponsiveness compared to other developmental stages.
• Determined developmental temperature thresholds aligned with existing degree-day models.

Conclusions:

• Differential scanning calorimetry provides valuable insights into the thermal tolerance and developmental responses of H. halys.
• The third instar is the critical stage for assessing temperature-dependent survival and distribution.
• This calorimetric approach can accelerate the development of degree-day models for improved invasive species management and control efforts.