Unravelling the Impact of Climate Change on Honey Bees: An Ensemble
Modelling Approach to Predict Shifts in Habitat Suitability in
Honey bees play a vital role in providing essential ecosystem services
and contributing to global agriculture. However, the potential effect of
climate change on honey bee distribution is still not well understood.
This study aims to identify the most influential bioclimatic and
environmental variables, assess their impact on honey bee distribution,
and predict future distribution. An ensemble modelling approach using
the BIOMOD2 package in R was employed to develop three models, i.e., a
climate-only model, an environment-only model, and a combined climate
and environment model. The climate-only model focused on the bioclimatic
factors: radiation of the wettest and driest quarters, and temperature
seasonality. By utilizing bioclimatic data from 1990 to 2009, combined
with observed honey bee presence and pseudo absence data, this model
predicted honey bee distribution for two future time spans: 2020-2039
and 2060-2079. The climate-only model exhibited a True Skill Statistic
(TSS) value of 0.85, underscoring the pivotal role of radiation and
temperature seasonality in shaping honey bee distribution. The
environment-only model incorporated environmental variables: proximity
to regional ecosystems (floral resources), foliage projective cover, and
elevation. This model demonstrated strong predictive performance, with a
TSS of 0.88, emphasizing the significance of environmental variables in
determining habitat suitability for honey bees. Remarkably, the combined
model had a higher TSS of 0.96, indicating that the combination of
climate and environmental variables enhances the model’s performance.
Predictions for the 2060-2079 period revealed a concerning trend of
100% transition of highly suitable land into moderately (0.54%),
marginally (17.56%) or not suitable areas (81.9%) for honey bees.
These results emphasize the critical need for targeted conservation
efforts and the implementation of policies aimed at safeguarding honey
bees and the vital apiary industry.