With his bright colors, signature rounded “hump,” and confident personality, Humphrey the humphead wrasse is hard to miss as he glides alongside sharks in the Tropical Reef Aquarium’s Outer Reef habitat.

Recently, aquarists noticed Humphrey was “flashing,” rubbing his sides against rocks and other surfaces, essentially a fish’s way of saying, “I’m itchy!” Flashing often suggests irritation caused by external parasites.

Because fish can’t exactly “hold still” on command, Humphrey was safely anesthetized so the veterinary team could perform a thorough, low-stress examination.

During the exam, the team evaluated his gill health, performed skin scrapes to check for external parasites under a microscope, assessed his fins and scales, paying close attention to areas parasites commonly target, and conducted an ultrasound to examine his internal organs.

“We didn’t directly observe any parasites under the microscope,” said Head Veterinarian Dr. Karen Wolf. “Parasites can be difficult to detect, especially beneath the dense scales of a humphead wrasse. However, based on his flashing behavior, we elected to treat him for external parasites.”

Dr. Wolf added, “It’s important to remember that parasites are naturally present in ocean environments. Even in well-managed aquaria, low levels can exist without causing harm. However, when parasite burdens increase to irritating levels, fish may begin to flash in response.”

After treatment, aquarists report that Humphrey is no longer flashing and appears comfortable again. Even better, his appetite was never affected, which is always a reassuring sign. He continues to eat well and interact normally with his environment.

“We’ll continue to monitor him closely,” said Dr. Wolf, “but at this time, he’s back to being his bold, charismatic self.”