Insights into varroa mite (Varroa destructor) infestation levels in local honeybee (Apis mellifera) colonies of Ethiopia

Abstract

The varroa mite (Varroa destructor) is the most economically important parasitic pest of honey bees (Apis mellifera) that causes global colony decline and loss. Since its first detection in Ethiopia in 2010, little is known about the current infestation levels and contributing factors to the mite's distribution across the country. In this study, we conducted a large‐scale assessment of varroa prevalence and infestation levels in managed colonies across three potential beekeeping regions of Ethiopia; Oromia, Amhara and Southern Nations, Nationalities and Peoples Region (SNNPR). A total of 360 samples from 39 apiaries were collected following standard protocols and the mite prevalence and infestation levels were determined using the established method of varroa research. Overall, 89% of sampled colonies were infested by the mite, with varying prevalence rates across the regions: 95.8% in Oromia, 85.2% in Amhara and 71.9% in SNNPR, indicating the widespread nature of the parasite throughout the country. The varroa infestation levels were lower in local hives (2.6 ± 5.9) than in frame hives (5.0 ± 0.9), and significantly higher in brood bees (5.6 ± 0.8) than in adult bees (1.93 ± 0.17) (p < 0.001). Possible factors contributing to the varied mite prevalence and infestation levels in the country include differences in agro‐ecology, beekeeping practices, host age preference and the nature of bee hives. Therefore, our study provides insights into the current status of varroa prevalence and associated factors across regions in Ethiopia. Further investigation is required to explore the probable impact of the parasite on the health and productivity of local honey bees, in order to design future monitoring strategies.

Epidemiology, factors influencing prevalence and level of varroosis infestation (Varroa destructor) in honeybee (Apis mellifera) colonies in different agroecologies of Southwest Ethiopia

“…Several studies conducted in Ethiopia have examined the prevalence of Varroa infestation in honeybee colonies and reported a high prevalence ranging from 30.5% to 91.8%. Furthermore, the infestation has been reported to have significant detrimental effects on both honeybee colonies and honey production, posing a considerable challenge for the country's beekeeping industry ( Begna, 2015 ; Godifey, 2015 ; Mezgabu et al, 2016 ; Nega et al, 2019 ; Shegaw et al, 2022 ; Gela et al, 2023 ). Furthermore, studies have shown that Ethiopian honey bee antennae exhibit an increased level of gene expression of the odorant binding protein OBP14, suggesting a potential improvement in detection and elimination of reproducing mites ( Gebremedhn et al, 2023 ).…”

“…These disease assaults continue to have a serious effect on honeybees and their products, despite the lack of many solid kinds of research on the effects of the disease ( Shegaw et al, 2022 ). Varroosis is one of the serious honeybee diseases that affected honey production in Ethiopia ( Begna, 2006 ; Shegaw et al, 2022 ; Gela et al, 2023 ). However, evidence on the magnitude and distribution of varroa mites is still insufficient ( Godifey, 2015 ).…”

High Rates of Honey Bee Colony Losses and Regional Variability in Ethiopia Based on the Standardised COLOSS 2023 Survey

“…However, some honey bee populations have been identified as tolerant against this pest and able to survive even without anti-varroa treatment [ 12 , 13 , 14 , 15 ]. Since the detection of varroa for the first time in northern Ethiopia’s Tigray region [ 16 ], several studies have been conducted on its distribution and prevalence in the country [ 17 , 18 , 19 ]. A national survey conducted in Ethiopia, which covered all regions except Tigray, showed a wide distribution and up to 95.8% prevalence in the country with a significant variation between regions [ 18 ].…”

“…Since the detection of varroa for the first time in northern Ethiopia’s Tigray region [ 16 ], several studies have been conducted on its distribution and prevalence in the country [ 17 , 18 , 19 ]. A national survey conducted in Ethiopia, which covered all regions except Tigray, showed a wide distribution and up to 95.8% prevalence in the country with a significant variation between regions [ 18 ]. The prevalence of varroa in Ethiopia was reported to be influenced by several factors including agroecology and management systems [ 19 ].…”