Insects perform numerous vital ecosystem services, so widespread reports of insect declines are of considerable concern. However, there are huge knowledge gaps with regard to the extent and scale of insect declines, with most studies being from Europe and North America and very few long-term data sets on insect population change in Asia, Africa or South America. The current study describes trends in abundance of insect pollinators visiting loquat (Eriobotrya japonica) over 13 years (2006–2018) in ten widely-spaced orchards in the Pothwar region of Pakistan. Results reveal a significant and concerning decline of 89.9% in overall abundance of flower-visitors across the study period. All pollinator species declined; for example numbers of Apis dorsata fell by 97%, A. mellifera by 96%, A. cerana by 93%, and Bombus haemorrhoidalis by 84%. Declines were non-linear, being most rapid in 2006–2009. In parallel, the average yield per loquat tree fell by 61%; sugar and organic acid content also declined. Total flower-visiting insect abundance was a strong predictor of crop yield and quality over time and across sites, while pollinator species richness was less powerful. Trees that were given supplemental pollination by caging them with small honeybee colonies during flowering showed no decrease in yield or fruit quality. These results indicate that declines in populations of wild pollinators are negatively impacting loquat production and the livelihood of the small farmers of the area. Further research to identify the cause of these insect declines is urgently needed, alongside development of conservation strategies for pollinators in this region.

昆虫执行许多重要的生态系统服务，因此昆虫衰退的广泛报道引起了人们的极大关注。然而，关于昆虫减少的程度和规模存在巨大的知识差距，大多数研究来自欧洲和北美，亚洲、非洲或南美昆虫种群变化的长期数据集很少。目前的研究描述了 13 年（2006 年至 2018 年）期间，在巴基斯坦 Pothwar 地区的十个宽阔果园中访问枇杷（ Eriobotrya japonica ）的昆虫传粉者的丰度趋势。结果显示，在整个研究期间，花卉访客的总体丰度显着下降了 89.9%。所有传粉媒介物种都减少了；例如，Apis dorsata的数量下降了 97%，A. mellifera 96​​%、A. cerana 93% 和Bombus hemorrhoidalis84%。下降是非线性的，在 2006-2009 年间最为迅速。与此同时，每棵枇杷树的平均产量下降了 61%；糖和有机酸的含量也有所下降。随着时间的推移和跨地点，访花昆虫的总丰度是作物产量和质量的一个强有力的预测指标，而传粉媒介物种的丰富度则不那么强大。在开花期间通过用小蜂群笼住它们进行补充授粉的树木显示产量或果实质量没有下降。这些结果表明，野生传粉媒介数量的下降对该地区的枇杷生产和小农的生计产生了负面影响。迫切需要进一步研究以确定这些昆虫减少的原因，同时制定该地区传粉媒介的保护策略。