Margaret River
South West, WA · Shire of Augusta-Margaret River · Relative human–shark interaction conditions
Town is inland; public coastal-risk area covering Prevelly / Gracetown surf coast.
Experimental · uncalibrated
Evidence freshness: 19 Sept 2026, 3:13 pm
Dominant evidence class for the index: Historical seasonal association
Why?
- •Area roll-up of 1 sub-locations (0.5×max + 0.5×mean public index)
- •Highest localised index: Prevelly (35.5/100 · MODERATE)
- •Sub-location precision limited where data is MOCK or incomplete
- •Water temperature (~17.7°C) favours great white shark thermal suitability
Margaret River interaction risk is a development roll-up of 1 sub-locations (0.5*max(child publicIndex)+0.5*mean(child publicIndex); conf=min(child); hazard=max(child)). Public index 35.5/100 — MODERATE. Combined confidence moderate. Sub-location data may be MOCK or incomplete; this is not an operational warning system. Always follow lifeguard instructions, beach closures, and official WA SharkSmart / DPIRD advice. vShark is not a government or SLSA product.
Species conditions
No species contribution breakdown for this assessment.
South-western transition hypothesis: still temperate-leaning, with increasing mixed-assemblage uncertainty toward Cape Naturaliste. Hypothesis to be tested.
Recent detections / sightings
No shark observations are stored for this location. That is a data gap, not evidence that sharks are absent. SharkSmart WA is not machine-connected.
CACHED rows are curated public notices, not a live tagged-shark feed, and do not enter the 0–100 as live detections.
Environmental state
- air_temperatureLIVE15.5 °C20 Sept 2026, 3:00 am
- rainfall_24hLIVE5.4 mm20 Sept 2026, 3:00 am
- sstLIVE17.7 °C20 Sept 2026, 3:00 am
- swell_heightLIVE4.4 m20 Sept 2026, 3:00 am
- wind_direction_degLIVE268 deg20 Sept 2026, 3:00 am
- wind_speed_knLIVE11.4 kn20 Sept 2026, 3:00 am
Human exposure
- Class
- estimated
- Popularity proxy
- high
- Model exposure
- 0.50
Activity classes: surfing, bodyboarding, foiling
Estimated, not observed counts. No false precision.
Persistent spatial context
- beach
- reef
- headland
Geomorphology is persistent context, not a transient observation.
Data gaps
- sub location live feeds
Missing data reduces confidence; it does not mean low risk.
Nested locations
- PrevellyMODERATE
Nearby locations
Data coverage
Where vShark knows little is as important as where it knows more. Missing coverage does not mean low risk.
- Shark observation coverageNONE
SharkSmart WA / DPIRD detections are not machine-connected. No live tagged detections in vShark.
- Ocean coverageMODERATE
Open-Meteo marine SST and wave height at a regional centroid — not a beach sensor.
- Weather coverageMODERATE
Open-Meteo forecast weather at a regional centroid.
- Ecology coverageLOW
No live prey, whale, seal or productivity feed. Seasonal notes are hypotheses or climatology.
- Human exposure coverageLOW
Estimated from popularity class, weekday/weekend and swell. Not a head-count.
- Sensor coverageNONE
No acoustic, camera, drone or eDNA adapters connected.
- Historical coverageLOW
Incident reconstructions are added as frozen validation cases, not a complete history.
NOW / HISTORY — recent assessments
Append-only model outputs. New model versions do not rewrite these rows.
| When | Band | Index | Confidence | Model |
|---|---|---|---|---|
| 19 Sept 2026, 3:13 pm | MODERATE | 35.5 | MODERATE | 0.1.0-dev |
| 18 Sept 2026, 8:29 pm | MODERATE | 24.9 | MODERATE | 0.1.0-dev |
Evidence hierarchy
- Direct recent detection — Tagged receiver, verified instrument detection, or equivalent in the relevant window.
- Verified sighting — Sighting confirmed by a responsible authority or trained observer.
- Multiple corroborated observations — Independent reports that agree in space and time.
- Strong ecological proxy — Prey aggregation, carcass, or similar with documented association — still a proxy.
- Environmental habitat suitability — Temperature, depth, and similar suitability — not presence.
- Historical seasonal association — Climatology / phenology prior. Not a live observation.
- Long-term background prevalence — Baseline occurrence in the region. Weakest for now-casting.
Methodology
Relative interaction risk, not attack probability. Official advice outranks this page. Methodology · Data sources