Abstract:
Sustainable development of Apis cerana colonies is highly influenced by nutritional adequacy and
efficiency of pollen foraging. Due to limited scientific research on Apis cerana in Sri Lanka, a
systematic understanding of its nutritional dynamics is essential for ensuring sustainable
beekeeping practices. This study was conducted over two months, from March to May 2025, in
the Kalutara District (Low Country Wet Zone), Sri Lanka, to assess the impact of protein
availability and pollen collection on colony development stages across eight Apis cerana hives
under tropical field conditions. Pollen collection was quantified at one-day intervals using
repeated one-minute forager counts conducted in the mid-morning. A forager was defined as a
worker bee returning with visible pollen loads, averaged over four replicates per hive. Concurrent
photographic inspections were conducted every two weeks to evaluate the Colony Status Index
(CSI), based on total brood area, honey reserves and pollen stores, providing a comprehensive
measure of colony health and growth. Results demonstrated a strong positive correlation
between total brood area and pollen foraging activity, described by the regression model
y = 0.1285x with a determination coefficient (R²) of 0.814, indicating that pollen collection rate is
closely linked to brood development. Colonies with brood areas greater than 774 cm² showed
significantly higher pollen collection rates (>20 loads/min), while those below 322 cm² displayed
lower rates (<12 loads/min). Higher CSI scores were associated with increased brood density and
honey storage, validating pollen intake as a key driver of internal colony productivity. Simple
linear regression and one-way ANOVA were used to analyse these relationships, with regression
emphasized for model fitting and prediction. This research highlights the predictive power of
integrating behavioural data (pollen foraging) with the Colony Status Index to evaluate and
forecast colony sustainability. The findings emphasize that maintaining continuous pollen
availability could enhance colony performance and long-term sustainability in artificial Apis
cerana hives.
