Yellow Downlooker Snipefly (Rhagio strigosus)
Key Details
| Taxonomic Groups: | Invertebrate > insect - true fly (Diptera) > Soldier fly or ally |
| Red List Status: | Vulnerable (Not Relevant) [VU(nr)] |
| D5 Status: | Included in the baseline Red List Index for England (Wilkins, Wilson & Brown, 2022) |
| Section 41 Status: | (not listed) |
| Taxa Included Synonym: | (none) |
| UKSI Recommended Name: | Rhagio strigosus |
| UKSI Recommended Authority: | (Meigen, 1804) |
| UKSI Recommended Qualifier: | (none specified) |
| Red List Citation: | Drake, 2017 |
| Notes on taxonomy/listing: | (none) |
Criteria
| Question 1: | Does species need conservation or recovery in England? |
| Response: | Yes |
| Justification: | Multiple records from Oxfordshire, Surrey and Berkshire over the past 30 years, however, there are multiple sightings from the same areas which may indicate that the fly has a stable if somewhat limited distribution. |
| Question 2: | Does recovery/ conservation depend on species-specific actions? |
| Response: | Yes |
| Justification: | As with many of the species being researched here the population status and distribution is not fully understood and as with other species surveying and recording to get a better picture of the flies situation is needed before any specific actions can be applied to sites of interest. |
| 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: | Yes |
| Justification: | Areas of old grassland within scrub or woodland or hedgerows, on chalk, with solitary trees, seems to be the preferred habitat. Any management aimed at preserving or increasing suitable habitat may allow some spread if populations exist at former sites. Conventional management of rides and glades would be positive action in general. |
Species Assessment
| Current step on the Species Recovery Curve (SRC): | 4. Autecology and pressures understood |
| Recovery potential/expectation: | Medium-high |
| National Monitoring Resource: | Opportunistic - insufficient |
| Species Comments: | Potentially the species is at the northern point of its distribution (climatic range) |
Key Actions
Key Action 1
Proposed Action: Tailored surveys of the required habitat in the adult flight period to be completely sure whether the previous populations are present before more specific targeted actions may be implemented if required
Action targets: 3. National Monitoring Plan agreed and implemented
Action type: Targeted monitoring
Duration: 2 years
Scale of Implementation: ≤ 10 sites
High priority sites: Buckinghamshire, Wardrobes Lane, (SP818016), Berkshire, Aston Upthorpe Downs, (SU545838, SU546839), Oxfordshire, Warburg BBOWT, 2006, (SU718878) also older records from (SU676882, SU685874, SU683869) 2005 and Berkshire Sodom Lane (SU58427610) and Surrey Headley Warren (TQ194538) in 200/2002.
Comments: To determine if older sites are still populated and also to discover if other viable sites have undiscovered populations. This would then hopefully allow for more targeted approaches. Surveyors need to be capturing scales of scrub inclusion on the grassland, sward heights, extent of "bare ground", hill slope aspect etc.
Key Action 2
Proposed Action: Conservation management relation to rotational clearance/.cutting of woodland ridea and edges under the assumption from previous records and sites that the fly relies on transitional edges between woodland and more open areas.
Action targets: 4. Autecology and pressures understood
Action type: Habitat management
Duration: >10 years
Scale of Implementation: ≤ 10 sites
High priority sites: Buckinghamshire, Wardrobes Lane, (SP818016), Berkshire, Aston Upthorpe Downs, (SU545838, SU546839), Oxfordshire, Warburg BBOWT, 2006, (SU718878) also older records from (SU676882, SU685874, SU683869) 2005 and Berkshire Sodom Lane (SU58427610) and Surrey Headley Warren (TQ194538) in 200/2002.
Comments:
Key Action 3
Proposed Action: Liaison with landowners and local authorities to identify the need to protect hedgerows and specifically isolated trees within these that adult males may use for gathering while awaiting females.
Action targets: 2. Biological status assessment exists
Action type: Advice & support
Duration: >10 years
Scale of Implementation: ≤ 10 sites
High priority sites: Buckinghamshire, Wardrobes Lane, (SP818016), Berkshire, Aston Upthorpe Downs, (SU545838, SU546839), Oxfordshire, Warburg BBOWT, 2006, (SU718878) also older records from (SU676882, SU685874, SU683869) 2005 and Berkshire Sodom Lane (SU58427610) and Surrey Headley Warren (TQ194538) in 2001/2002.
Comments:
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.