Sponge pumping: Seein' with fluorescein! @PawlikLab

Uploaded August 2016 | Updated September 2026, 42 minutes ago

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Visualizing the movement of water through 4 species of Caribbean sponges using fluorescein dye, a non-toxic fluorescent tracer. Video shot on the coral reef off Carrie Bow Cay, Belize, and near the Aquarius undersea research lab off Islamorada, in the Florida Keys.

Coral reef rescue: Save the parrotfishes!

$Diving Looe Key, Florida Keys Change to 4K resolution if your system wont skip! Video made 7 March 2023 while diving with Captain Hooks Scuba Center of Big Pine Key. Looe Key Reef is very shallow (30 ft max depth, mostly 25 ft) with no drop off, formerly having very large live coral heads. Hard coral cover is now a small fraction of what it was in the past, but whats left looks good. Some observations: (1) Huge parrotfishes! Shows that marine park protection works! Also, schools of large blue tangs. Lots of herbivory by fishes. As a consequence, seaweed abundance is low, and pink coralline algal crusts are easily seen. Listen to the sound of large parrotfishes grazing (4:07). (2) Sea fans are thriving, no evidence of sea fan disease (aspergillosis) that was a much-discussed emerging threat in the 1990s. (3) Lots of black grouper. Small snappers and grunts hide in sea fans showing fear of reef sharks, which are present (9:30, 10:10). (4) Tragic loss of many large coral heads (4:20). But, higher coral survivorship than expected with recent SCTLD outbreaks. Out-planted staghorn corals seem to be doing well. (5) Surprisingly large giant barrel sponges for a very shallow site. (6) Despite hiding behavior of fishes, parrots and other fishes were remarkably unafraid of divers.$