Lotka-Volterra — dH/dt presa

dH/dt = aH − bHP.
Created by
Renato Passos, Eng. de Software
Reviewed by
Renato Passos, Eng. de Software

Last updated: Apr 18, 2026

dH/dt
4,00 indiv/t

About this calculator

This calculator solves the Lotka-Volterra prey equation (dH/dt = aH − bHP). It predicts how prey population (H) changes over time, balancing natural growth (a) and predation-driven losses (bHP).

The formula accounts for two dynamics: (1) exponential prey growth (aH), proportional to population density; and (2) prey loss from predation (bHP), which depends on both prey and predator abundance. The model is foundational in ecological population studies.

Use this tool in ecological research to simulate predator-prey systems, such as lemmings and arctic foxes. It's applicable for academic studies, conservation planning, or understanding natural population fluctuations.

Caveats: the model ignores external factors like climate or resource availability. Results are theoretical and require adjustments for real-world complexity. Initial values for H, P, a, and b must be grounded in empirical data for accuracy.

Frequently asked questions

What does the variable H represent in the equation?

H represents prey population density at a given time, measured in individuals per unit area.

Why does predation reduce H nonlinearly?

The bHP term depends on both prey and predator abundance, creating a multiplicative relationship that models random encounters between species.

When should this calculator be used instead of the full model?

Use it when focusing exclusively on prey dynamics without analyzing the predator equation (dP/dt).

How do the values of a and b affect results?

a controls prey exponential growth rate, while b determines predator hunting efficiency.

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