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Spotted handfish are a critically endangered anglerfish. Monitoring of the species has, in the past, been undertaken via underwater visual census (UVC) parameterised with fixed length 100 m × 3 m strip transects measured with reel lines. However, the sparse distribution and cryptic nature of handfish resulted in low statistical power to track populations through time. To achieve reasonable confidence of detecting change ~ 40 transects are required for density estimates, making the logistical constraints of monitoring onerous. We trialled a new survey method for UVC at one study site with a known local population of fish, replacing reel transects with variable length strip transects parameterised with a diver towed Global Positioning System (GPS) float. From 18 transects we determined a density of 24 (± 3.5) handfish per hectare, but bootstrapping suggested little improvement in precision occurred after 8 transects …