Data from: Post-harvest population reservoirs of Coffee Berry Borer, Hypothenemus hampei (Coleoptera: Curculionidae) on Hawai'i Island

Coffee Berry Borer, Hypothenemus hampei Ferrari (CBB), is the most damaging insect pest of coffee worldwide. Old coffee berries (raisins) are widely acknowledged as CBB reservoirs, yet few studies have attemped to quantify CBB populations in raisins remaining on farms post-harvest. We collected ground and tree raisins at six coffee farms on Hawai'i Island to assess raisin density, infestation, CBB abundance, and adult mortality in three areas of each farm: trees, driplines (ground below the tree foliage), and center aisles (ground between tree rows). We also assessed infestation of the new season's crop by conducting whole-tree counts of infested green berries. Mean raisin density was significantly higher in the dripline compared to the center aisle and trees (131 vs. 17 raisins/m2 and 12 raisins/tree, respectively). Raisin infestation was significantly higher in samples from trees (70%) relative to those from the dripline (22%) and center aisle (18%). Tree raisins had significantly higher CBB abundance compared to both areas of the ground (20 vs. 3–5 CBB/raisin). Adult mortality was significantly higher on the ground (63–71%) compared to the trees (12%). We also observed a significant positive correlation between ground raisin density and infestation of the new season's crop. Across all farms, we estimated that 49.5% of the total CBB load was present in dripline raisins, 47.3% in tree raisins, and 3.2% in center aisle raisins. Our findings confirm the importance of whole-farm sanitation in CBB management by demonstrating the negative impact that poor post-harvest control can have on the following season's crop.