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Pollination is an ecosystem service that is in jeopardy globally. Decreasing trends in wild pollinator populations are primarily attributed to habitat loss and degradation. These concerns are especially apparent in the Rainwater Basin of Nebraska, USA where more than 90% of the land has been cultivated and 90% of the wetlands have been lost. We compared hymenopteran and dipteran pollinator abundance, richness, and diversity in 28 wetlands and their adjacent uplands within 3 dominant land-condition types: cropped, restored, and reference state. We used vane traps to capture local pollinator insects and sweep nets to collect insect pollinators on flowers. Vane-trap captures revealed a greater abundance, richness, and diversity of hymenopteran pollinators in uplands as compared to wetlands over the entire growing season in all land-condition types. However, net collections showed that hymenopterans foraged more in wetlands than in uplands, especially in restored wetlands. The exception was September when hymenopterans were captured in uplands more than wetlands while feeding on late season forbs. Dipteran vane-trap and sweepnet captures primarily consisted of hoverflies (Syrphidae). Hoverflies were more abundant in wetlands than uplands. All pollinators used both wetlands and uplands for resources. Thus, insect-pollinator conservation can be enhanced by promoting native forb communities and pollinator habitat through wetland restoration and the planting of buffer strips.

In 2016, the annual value of all global crops dependent upon pollination was valued at $ 235–$ 577 billion (US$). Pollination service is threatened by habitat loss, pesticides, and climate change. We collected potential pollinators with blue vane traps in native grasslands, Conservation Reserve Program (CRP) lands, and cropland (land use), and their embedded playa wetlands (land type) in the Southern High Plains of Texas (SHP). We collected vegetation data that included floral cover, floral diversity, native grass cover, introduced grass cover, canopy gap, and duff cover. Our objective was to determine if individual vegetation characteristics influenced potential pollinator abundance and richness in addition to land use or land type as a whole. The top model explaining abundance was land use, land type, and floral cover. Floral cover had a positive influence on all land uses. The top model that explained insect richness was land use x floral cover, land type, canopy gap, and duff cover. Floral cover positively influenced insect richness in native grasslands but negatively influenced cropland and CRP richness. Percent of canopy gap had a slight negative influence on insect richness, and duff cover positively influenced richness. Our recommendations to land managers are to protect playas to preserve undisturbed areas and native floral resources and seed all future CRP contracts with floral rich plantings to provide for pollinators over the entire growing season. Implications for insect conservation Our results show that vegetation characteristics shared by all land uses such as floral cover, canopy gap and duff cover influence pollinator abundance and richness. Therefore, conserving playa wetlands and programs such as the CRP have the potential for enhancing pollinator habitat in working landscapes of the SHP of Texas.

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