I’m trialing a Diving-PAM II alongside photo-quadrat transects to sharpen coral health assessments during biodiversity surveys. For those running conservation-focused monitoring in surgey sites, how are you balancing Fv/Fm readings and quick eDNA grabs with enough throughput to cover 50 m transects (we managed 8 in 90 minutes at Heron Island last month) without compromising data quality?
We pre-load Sterivex cartridges and [redacted] syringes so eDNA grabs happen at the same “three fixed waypoints” we use for Fv/Fm (0, 25, 50 m), with blackout caps on lanyards to get 15–20 s dark adaptation even in surge. That kept us at 6–9 transects per 90 min at North Stradbroke; small caveat is you’ll under-sample shaded morphs, so once per dive we add a quick extra read on a branching colony flagged by the photo-quadrat — like checking a pulse on a rollercoaster. If swell spikes, we drop PAM to 2 waypoints and bump the eDNA volume instead.
I slip a tiny about 5 mm silicone standoff over the Diving-PAM II fiber and brace it on the quadrat frame — cuts aim time in surge so Fv/Fm is a 10–15 s touch-and-go; we time eDNA on the return leg like @mperryman91, but the standoff adds a bit of drag so keep it low-profile… Are you dark-adapting in situ or shooting pre-dawn?