What does it do?
The moth4pop model simulates the lives of moths.
It simulates their survival from larvae to adults, the dispersal of adults from their larval habitat and egg deposition, accounting for the effects of light pollution and weather.
This enables the model to predict the relative abundance of moths across a landscape.
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Where does it come from?
The moth4pop model was created by researchers at the UK Centre for Ecology & Hydrology with the help of Butterfly Conservation and the Garden Moth Scheme.
Moth4pop model development is led by Claudia Acerini.
How does it work?
Moth4pop reads in a landcover map plus additional maps giving the locations of fine-scale habitat features (e.g. hedgerows, field margins).
It combines these with expert opinion estimates of the amount of larval habitat resources each landcover type is expected to offer the moths that are being modelled. This allows the model to map the larval habitat resources provided by the landscape.
The model also reads in a light pollution map and information on larval densities in lit and unlit locations.
It uses this to place larvae in the landscape, putting more in places where there are more larval habitat resources and less light pollution.
The model uses information on seasonal weather conditions and moth weather responses to calculate how many larvae survive to become adults.
It then uses information on movement ranges to disperse the adults across the landscape assuming the density of dispersed adults decreases with distance away from their original larval location.
The model calculates the distribution of eggs laid assuming that adults deposit more eggs in places nearer to their original larval location and in places with more larval habitat resources.
These eggs turn into larvae, with the maximum allowed number of larvae in any given location capped according to the amount of larval habitat resources and level of light pollution.
The model loops round and round multiple generations to work out where the moths would be able to survive, given the composition and configuration of habitat resources provided by the input landscape.
Moth4pop can also be run for multiple years using landcover maps and weather conditions that change over time and we’re actively developing this part of the model.
What knowledge does the model use?
The moth4pop model was originally parameterised for five moth groups – low mobility generalist moths, high mobility generalist moths, low mobility woodland moths, high mobility woodland moths, and low mobility grassland moths. We are now exploring making species-specific models.
It currently uses:
- expert opinion on moth habitat preferences from a survey of 7 moth experts
- literature data on larval densities, dispersal distances and weather responses
How do we know it works correctly?
We compare moth4pop model predictions to observed moth abundances recorded at 225 sites across Great Britain through the Rothamsted Insect Survey.
How has moth4pop been used?
We have used moth4pop to explore how future land use changes might affect moths over time, working with Defra’s national evidence teams.
Visit our pages on supporting decision-making to find out more about this work.
*4pop models 