Biodiversity of Non-Apis Bees (Hymenoptera: Apoidea) in the Potohar Region of Pakistan

Bees are essential for providing ecosystem services such as pollination to many crops worldwide. However, there is growing concern over the decline of bee populations, which threatens agricultural productivity. Despite the known importance of bees, including non-Apis bees, in crop pollination, their diversity and distribution remain understudied in the Potohar region of Pakistan. The current study addresses this gap by assessing the biodiversity of non-Apis bees across five districts of the Potohar region, Pakistan: Attock, Chakwal, Jhelum, Rawalpindi, and Islamabad. The objective was to evaluate the species richness, diversity, and evenness using various richness and diversity indices. A total of 2005 specimens, representing 27 species from 13 genera and five families (Apidae, Halictidae, Colletidae, Megachilidae, and Andrenidae), were collected over 24 surveys conducted between 2012 and 2015. Two richness indices, Shannon’s Species Richness Index and Margalef’s Richness Index, showed moderate to high species richness across localities, with values ranging from 2.378 to 4.186 and 1.508 to 2.711, respectively. Simpson’s Index and Simpson’s Reciprocal Index exhibited dominance and high diversity across sites, with values ranging from 0.094 to 0.880 and 4.446 to 11.315, respectively. Additionally, the Shannon–Wiener and Shannon Equitability indices indicated fairly even species distributions across localities. A correlation analysis revealed strong positive relationships between most indices, except for Simpson’s Reciprocal Index, which showed negative correlations with the other indices. These findings provide crucial insights into the biodiversity of non-Apis bees in the Potohar region and underscore the importance of maintaining diverse pollinator communities to support sustainable agriculture in the area.