Sea Aster Bee (Colletes halophilus)
Key Details
| Taxonomic Groups: | Invertebrate > insect - hymenopteran > Bee |
| Red List Status: | (Not Relevant) [(not listed)(nr)] |
| D5 Status: | |
| Section 41 Status: | (not listed) |
| Taxa Included Synonym: | (none) |
| UKSI Recommended Name: | Colletes halophilus |
| UKSI Recommended Authority: | Verhoeff, P.M.F., 1944 |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | (not listed) |
| Notes on taxonomy/listing: | Listed in Falk (1991) as Nationally Notable (Na). |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | Britain has a global responsibility to conserve this bee, which is restricted to North Sea coastal sites in western Europe. Although it has never been accorded a Red Data Book status, this bee will be highly vulnerable to climate change-driven sea levels rises. It forages on Sea Aster in saltmarshes, which is under threat from coastal squeeze between rising sea levels and engineered coastal defence walls. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | Extensive stands of Sea Aster are needed in order to support viable bee populations. Stable clay slopes are needed for nesting. |
| Question 3: | At a landscape scale, would the species benefit from untargeted habitat management to increase habitat mosaics, structural diversity, or particular successional stages? |
| Response: | No |
| Justification: | The bee is dependent upon upper saltmarsh communities rich in Sea Aster. Whilst foraging on Ragwort flowers is known, this is unlikely to be a successful alternative forage source at a population level. |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 6. Recovery solutions trialled |
| Recovery potential/expectation: | Low - Climate change |
| National Monitoring Resource: | Opportunistic - sufficient |
| Species Comments: | Necessary actions are well-understood. There is a need to create more upper saltmarsh vegetation rich in Sea Aster. This will require suitable design and species-specific needs considered in future managed realignment schemes, allowing for saltmarsh vegetation as well as mud flats and lower saltmarsh habitat creation in any coastal defence realignment work. |
Key Actions
Key Action 1
Proposed Action: Promote the creation of new saltmarsh habitats in coastal realignment schemes, through education/awareness for land managers and other partners.
Action targets: 6. Recovery solutions trialled
Action type: Education/awareness raising
Duration: >10 years
Scale of Implementation: National
High priority sites: Essex coast; north Kent coast; north Norfolk coast; Lincolnshire coast.
Comments: The need to create upper saltmarsh in managed retreat schemes needs to be disseminated to government agencies, local planning authorities and environmental consultancies through advice and guidance. Compensation schemes tend to focus on the loss of intertidal muds for over-wintering birds, which may be the fundamental reason behind any site designations, but the needs for other intertidal habitats should not be overlooked. Any such saltmarsh creation needs to be "future-proofed" against further sea level rises.
Key Action 2
Proposed Action: Seek to protect non-SSSI saltmarshes as Local Wildlife Sites to preserve current populations.
Action targets: 6. Recovery solutions trialled
Action type: Site protection
Duration: >10 years
Scale of Implementation: ≤ 50 sites
High priority sites: Essex and Kent coastline
Comments: Development pressure on saltmarsh fringes is most acute in the outer Thames estuary and The Solent (Hampshire). In sites where grazing of saltmarsh persists, this may provide a means of dialogue to control this.
Key Action 3
Proposed Action: Create stabilised nesting banks of sandy clay or clay above current high water mark as a key reproductive habitat requirement for the species
Action targets: 6. Recovery solutions trialled
Action type: Habitat creation
Duration: 3-5 years
Scale of Implementation: ≤ 50 sites
High priority sites: Outer Thames estuary and The Solent.
Comments: Nesting sites are vulnerable to being washed away during winter storms. Although nest entrances can be submerged by high tides, destruction of clay faces in saltmarsh will result in nest loss.
Acknowledgment:
Data used on this website are adapted from Threatened species recovery actions 2025 baseline (JP065): Technical report and spreadsheet user guide (Natural England, 2025). Available here.