Populations of bees and other pollinators are declining around the world. Learn about some of the challenges they are facing and how you can help.
![A green plant grows through cement](/subjects/pollinators/images/26164_sma_1.jpg?maxwidth=650&autorotate=false)
Encyclopedia of Life Photo
Habitat Loss
Pollinators require natural spaces with vegetation and flowering plants in which to live and forage for their food: pollen and nectar.The chief causes for pollinator habitat loss are agriculture, mining and human development:
- Alternate land uses may not provide overwintering, foraging, and nesting sites for pollinators that have specific habitat needs.
- Concrete, cement, and metal surfaces replace vegetated areas limit habitat for ground-nesting pollinators and provide scarce opportunities for pollinator foraging.
- Fragmented habitat may be too small to meet pollinator survival needs.
![Purple spotted knapweed plant](/subjects/pollinators/images/knapweed_NPS_1.jpg?maxwidth=650&autorotate=false)
NPS Photo
Non-Native Species
Pollinators require specific plants which provide nutrition and habitat to larval (immature stages) and adults pollinators.Native plants or wildflowers needed by pollinators may be out-competed by non-native species.
- Non-native plants may attract pollinators away from native species that are more nutritious and better food sources.
- Non-native species of pollinators may compete with native pollinators for pollen and nectar.
![Two people are spaying green vegetation with chemicals.](/subjects/pollinators/images/pesticide_2.jpg?maxwidth=650&autorotate=false)
NPS Photo
Pesticides
Pesticides are tools used to kill pest plants, insects, fungi, other pests. They include herbicides, insecticides, fungicides.
- Pesticides can adversely affect pollinators directly or some types of pesticides may remain in the environment for an extended time and affect multiple generations of pollinators.
- Insecticides applied to plant seeds may, when the plant is mature, contaminate pollen grains that are food sources for pollinators.
- Insecticides that don't directly kill may hamper the ability of pollinators to navigate or forage.
- Herbicides may kill important forage plants for pollinators.
![Three violet colored Frigid Shooting Star flower heads point downward with green leaves in the background](/subjects/pollinators/images/frigid-shooting-star_1.jpg?maxwidth=650&autorotate=false)
NPS Photo / Jacob W. Frank
Climate Change
- Flowering plants may occur farther north or at higher elevations as a response to warming temperatures and may become out of sync with their pollinators.
- The types and distributions of pollinators may change; pollinators adapted to warmer temperatures may expand their northward range, displacing other pollinators.
![Close-up photo of a tiny Hive Beetle](/subjects/pollinators/images/hive_beetle_eol2_2.jpg?maxwidth=650&autorotate=false)
Encyclopedia of Life Photo
- Key parasites and diseases affecting honey bees include Varrora mites, Hive Beetle, and Colony Collapse Disorder.
- There is more extensive transfer of parasites and diseases due to rapid travel and commerce.
- Non-native parasites and diseases infect native species.
Last updated: June 18, 2018