Mosquito density forecast from flooding: population dynamics model for Aedes caspius (Pallas)

Area of Science:

• Ecology
• Environmental Science
• Entomology

Background:

• Insect population dynamics are heavily influenced by environmental factors, particularly meteorological conditions for floodwater mosquitoes.
• Rainfall and temperature are critical drivers, triggering egg hatching and controlling immature development duration, respectively.

Purpose of the Study:

• To develop a simple, mechanistic model predicting floodwater mosquito population dynamics using only rainfall and temperature.
• To validate the model by fitting it to experimental field data for Aedes caspius.

Main Methods:

• A mechanistic model was created with three parameters: immature development duration (tdev), adult emergence rate function (f(t), characterized by emergence time scale τ), and adult depletion rate (α).
• The model was applied to fit experimental field data of Aedes caspius dynamics.
• Meteorological records (rainfall, temperature) were used as inputs for model validation.

Main Results:

• The adult emergence rate function accurately reproduced immature development data across sampled temperatures.
• Estimated values for tdev and τ showed Arrhenius behavior with temperature.
• The model successfully fit field data from a two-site CO2 trapping survey (2004-2005).
• Estimated depletion rates (mortality + emigration) followed a concave quadratic function of temperature, peaking at 0.5 per day around 22°C.

Conclusions:

• The developed model provides a tractable method for predicting floodwater mosquito population dynamics based on accessible meteorological variables.
• The model's parameters exhibit temperature-dependent relationships, offering insights into mosquito life cycle responses to climate.
• This modeling approach can aid in managing pest mosquito populations, such as Aedes caspius, by forecasting abundance.