Nitrogen Narcosis, The Martini Effect, and Rapture of the Deep: all are terms used to describe the effects of the alteration in consciousness when diving to depths greater than 100 feet (30 meters). This temporary and reversible effect is similar to being intoxicated or when one visits the dentist to have work performed with laughing gas (nitrous oxide), which is used as a dissociative anesthetic.
Anyone who has strapped on dive gear and ventured into the water using compressed air at depths out of the ordinary (more than 100 feet) has suffered from the effects of Nitrogen Narcosis. Symptoms such as dizziness, anxiety, a feeling of euphoria, reasoning, memory recollection problems, as well as an overwhelming sense of well-being are all potential side effects of visiting the abyss, but once back on the surface the effects of nitrogen narcosis goes away almost immediately.
The Narcosis Angelfish- (Centropyge narcosis) is also known as the Narc Angelfish and Deep Reef Pygmy Angel. By far, they are one of the most elusive pygmy angelfish – rarely seen – much less available for sale in the marine aquarium trade. This striking deepwater beauty sports a bold yellow coloration, flanked on each side of their body with a jet black spot. This species was formally described by Richard Pyle and Jack Randall in 1993, and is reported to attain a maximum total length of 3.5 inches (9 cm).
Narcosis Angelfish are found singly or in small groups, in deepwater fore-reef habitats ranging at depths from 361-420 feet (110-128 meters). They prefer rocky, cave laden vertical drop offs where large cracks in the rocky terrain reside. Although first thought to be an endemic species in the Eastern Central Pacific Ocean of Rarotonga, Cooks Islands, they have also been recently discovered in similar deepwater habitat over 700 miles (1199 kilometers) away in Tahiti.
So, how did this bright yellow, elusive fish obtain the species name of Narcosis? Thanks to a good friend and angelfish guru John Coppolino (copps), who corresponds with some well-known scientists and Ichthyologists from time to time, the story goes like this: Back in 1989, an aspiring graduate student named Richard Pyle had been in communication via snail mail (hand written letters) with friend and fellow fish enthusiast named Chip Boyle. The two were planning a deepwater dive trip in the hopes of collecting the first Peppermint Angelfish (Centropyge boylei).
Chip Boyle wrote that he observed a second angelfish that he didn’t recognize. The fish appeared strikingly similar to a Juvenile Lemonpeel Angelfish (Centropyge flavissima), but the spot on the side of the fish that is normally present in C. flavissima as a juveniles, was visible on the adults of this “new” yellow angelfish. During graduate student seminars, Richard Pyle and friend Randall Kosaki would frequently pass notes back and forth to one another in an attempt to make each other chuckle.
Richard passed along one such note stating “Chip says he saw ‘another’ new angelfish at 330 feet- all yellow with a black spot”. Kosaki, knowing Chip was using compressed air, dubiously wrote “Centropyge narcosis”, which in turn made Richard laugh. It was then that Richard Pyle made the decision that if this new angelfish species did exist, it would be named Centropyge narcosis.
This all came to fruition on their first deepwater dive together on the trip in Rarotonga while using compressed air. Richard Pyle collected the first ever specimen of Centropyge narcosis at a depth of 330-340 feet (100-103 meters). It wasn’t until half way through the assent to the surface, during the required decompression stops, where the effects of nitrogen narcosis started to fade. As he opened up his collection holding bucket to peek inside, he then realized that he had actually collected the elusive bright yellow fish with the black spot.
The Narcosis Angelfishes’ closest relative is the Colin’s Angelfish (Centropyge colini) which does show up from time to time in the aquarium trade. In their natural habitat, Narcosis Angelfish have been reported to frequently swim in an upside down position, continually maintaining their chest in close proximity to the rocky terrain.
When threatened, they have been observed to orient themselves in a head down position, dorsal spines pointed forward, taking on the appearance of a large fish-eating predator staring directly at the would be attacker. The two black spots that flank each side of the Narcosis could be mistaken for the large eyes of a fish-eating predator.
In the aquarium, they exhibit an almost identical personality and behavior to the Colin’s Pygmy Angelfish. Both species are more delicate pygmy angelfish species, having a preference for more subdued lighting and ample rock work arranged strategically to provide caves and overhangs. Ideal companions should include less active, and non threatening tank mates, as the goal should be to ensure the Narcosis Angelfish as one of the dominant fish in the display.
Deepwater fishes are few and far between in the marine aquarium trade, and when infrequently available, they normally fetch very large sums of money. Two of the most expensive Angelfish species include the barber pole colored Centropyge boylei and the bright yellow Centropyge narcosis. Both species are incredibly rare in the aquarium trade due to their restricted range, remote habitats and extreme depths where they reside.
There are but only a handful of very experienced scientists and collectors in the entire world who can safely dive to these extreme depths, much less harvest and then decompress some of these “twilight” species. Statistically, most twilight species of marine fishes that have become available to the trade go directly to the Asian market and fetch top dollars.
Being in the unique position as the Director of LiveAquaria.com for Drs. Foster and Smith, I am incredibly fortunate to have an opportunity to handle and condition some of the most uncommon, elusive, and hard to find fishes in the marine ornamentals trade. Having worked in the business now for thirty years, there are only but a handful of fishes which I would consider my personal “holy grail” species, of which I can honestly count on one hand.
In late August of 2012, we were graced with the very first Narcosis Angelfish to ever become available in United States. The fish was obtained by Quality Marine, located in Los Angeles California, who imported a single Centropyge narcosis. The fish was obtained from their exclusive “short supply chain” export stations in the Cook Islands, operated by Chip Boyle.
I have received, packaged and shipped literally thousands of fishes in my tenure in the marine ornamentals trade, and normally don’t get overly excited or nervous about their transport. For some reason the shipment which contained this Narcosis Angelfish was different — unlike any other. Not only was the fish incredibly expensive, but was also the only Narcosis Angelfish to ever grace our shores. The anticipation, anxiety and stress of the shipment began to build. The evening prior to receiving the fish – I could barely sleep – as all I could think about was is the little guy ok, is the transport going without a hitch, is the bag sealed well?
The following day when FedEx arrived at our door the excitement and anticipation was at its peak. As I opened the box, and gazed down on the fully inflated shipping bag full of oxygen and water, I breathed a sigh of relief to find the small yellow fish gleaming up at me! Now the reality of the situation set in and the pressure was on to properly acclimate, quarantine and condition this rare beauty so that we could bring this fish to market for the first time ever.
Conditioning and Husbandry
The Narcosis Angelfish was introduced directly to a special quarantine tank which contained a well-established reef set-up that already housed a variety of large polyp stony corals, and a few deepwater Acropora species. The temperate of the set-up was slowly adjusted down to 74° Fahrenheit (23 degrees Celsius), prior to introducing the fish into the display, and the LED lighting utilized to illuminate the aquarium was reduced to fifty percent power. Multiple sheets of Black Egg Crate lighting grid were also placed on top of the glass canopy in the right most section in an effort to provide a very dark area.
Like other twilight fishes, low lighting, along with cool water temperatures are a must for these fishes’ well-being and acclimation to a captive environment, with 74° being the extreme upper echelon of the temperature range. The aquarium already contained a small pair of ORA’s new Black Snowflake Clownfish (Amphiprion ocellaris var.), along with a few smaller species of wrasse, and a pair of Scarlet Cleaner Shrimp (Lysmata amboinensis).
The Narcosis Angelfish is a very shy and secretive fish by nature, and after the initial introduction into the conditioning aquarium, would refuse to venture out from the large cave in the center of the aquarium or out from underneath the overhanging Chalice corals. The fish was definitely sensitive to light levels, even subdued ones, but over time eventually adapted to the dimmed LED’s over the display. Feeding took a concerted effort, as the fish refused to eat any frozen foods. The next step was to try enriched live adult Artemia, which, over the course of a few days, coaxed the bright yellow angelfish to start feeding.
Over the next few weeks the Narcosis was weaned onto enriched frozen Artemia and minced Mysis shrimp, but the feeding response still wasn’t what I had hoped for as the fish would only eat food that passed by his favorite cave. It was then that I decided to implement Plan B to speed up the conditioning. The fish needed to feel like he owned the display and was in charge. The best way to achieve this was through the introduction of a similarly-shaped fish so that he could become the bully and not the passive bystander.
Success was achieved with the introduction of a very small Multicolor Angelfish (Centropyge multicolor), a close relative to the Narcosis Angelfish. The tiny dwarf Multicolor was literally one fourth the size of the Narcosis, and as I anticipated, immediately changed the demeanor of the laid-back Narcosis. The Narcosis immediately started to become more territorial and responsive to the other fishes in the display, as well as more receptive to prepared foods during feeding time. Surprisingly these two fish never once showed “extreme” aggression towards one another, but rather sorted out their hierarchy and size differences rather quickly. The only problems that were observed with housing two of very similar shaped dwarf angelfish together was when the Multicolor would “forget” who’s cave it was. The little Multicolor would venture into the cave owned and operated by the Narcosis, only to be immediately chased out by the big yellow bully.
Over the next several months the Narcosis angelfish became well accustomed to its surroundings and was out swimming in the open more often than not. The feeding response from the fish was like most other angelfish species that I have housed in my personal office aquariums. The Narcosis would wait impatiently, like an excited puppy dog, hoping to be fed when I walk up to the display with a cup filled with enriched frozen foods. The fish also adapted to the slow and incremental increase in lighting intensity, all the way back to full power which was achieved over a two month time frame.
The one downside to maintaining Centropyge narcosis with fleshy stony corals was its fondness for sessile corals such as Fungiids, where it would frequently pick at Cycloseris and Fungia species, as well as some Chalice Corals such as Echinophyllia, Echinopora, and Mycedium species on occasion in the conditioning aquarium. All of the Chalice fared well and were healthy enough to overcome the infrequent irritation from the Angelfish, but some of the Fungiids still have yet to fully recover to this day as they were the preferred target.
On October 18th, 2012, the fish was listed in the Diver’s Den(R) section of LiveAquaria.com, where it was snatched up in a matter of seconds for a retail price of $4999.99. A few days later, the Narcosis was packaged and shipped to a “rare fish collector” here in the United States. I am happy to report it is thriving. I was sad to see the fish go, but am very happy and proud to have had the unique opportunity to learn about and care for a fish that I had previously only seen in books or images of on the internet, and consider one of my top five “Holy Grail Species”. Now onto the next four!
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