DIVE DRY WITH DR. BILL #519: WHERE HAVE ALL THE "NUDIs" GONE?
Most of you know Pete Seeger's sad folk song "Where have all the flowers gone?" In it he lamented a chain of actions beginning with young men picking them... everyone... to give to young ladies, who married young men who became soldiers and went off to war returning to be buried in graveyards that became covered in flowers. Whew. Now all you "young" girls know why I "don't bring you flowers any more.
This week my song would be "where have all the nudis gone?" I won't sing it for you because my voice sounds like fingernails on a blackboard even when emanating from my shower. Oh, and the nudis haven't gone to places like Black's Beach in San Diego, Little Beach in Hawaii or Praia do Pinho in Brazil. Nudies go there, not nudis. Shame on you. Regular readers of my column should know that nudis are the often beautifully colored snails without a shell.
Recently I went out on Scuba Luv's King Neptune to dive three island sites looking mainly for squid eggs. I found carpets of them at Hen Rock and Long Point, but only scattered "candles" (the individual egg sacks containing up to 300 eggs each) at Garibaldi Reef. There wasn't a single living squid there... or even a dead one as predators had vacuumed them all up from the bottom. I saw and filmed lots of life on these three dives, but one thing shocked me. Read on.
I've been doing mostly shallow dives above 50 ft in the dive park to maximize my bottom time and gather the most video footage possible to share with you. On these dives I went reasonably deep, up to 114 ft. At those deeper depths I usually encounter lots of nudibranchs in the colder bottom waters... but on this day I saw a total of just one. It wasn't for lack of looking. The one I found, a Chromodoris macfarlandi, was less than an inch long and barely detectable to my aging eyes.
Now where have all the Acanthodoris, the Triopha, the Dialula, the Peltodoris, the Cadlina, the Mexichromis, the Doriopsilla, the Dendronotus, the Flabellina, the Janolus and the Hermissenda gone; not to mention their cousins the Aplysia and Navanax? I don't really expect you to answer that... or even remember the names. It's hard enough for me to do that. Besides, it's MY job to answer these pressing questions of existence!
I noticed that even at these depths, water temperature remains fairly warm for this time of year. The lowest temperature I got during the deeper dives was a balmy 57 degrees. Yes, I know... it sounds cold. But just two years ago it was 52-54 F at those depths and sites. One thing I've noticed is that nudis here, unlike nudies, actually seem to like cold temperatures. Some that are common in the colder mainland waters at shallower depths seem to be missing until one descends to depths below 80-100 ft off Catalina.
My educated guess is that these nudis may actually tolerate warmer water, but their food sources (hydroids, bryozoa, sponges, etc.) may prefer cooler waters. This is what we scientists refer to as an hypothesis. Now if I was well connected, I'd hastily scribble a grant request and get billions of $$$ from the U.S. government to research this question. I'd buy a research vessel, staff it with a lovely (and equally intelligent) bikini-clad crew and sail the ocean blue. Dream on, Dr. Bill.
Given the reality of the situation, I looked for reports from divers in other locations. A friend, Phil Garner, often dives mainland sites like Old Marineland with Merry and another mutual friend, nudi photographer Kevin Lee. They have reported a dearth of dorids and other nudis off "Lost" Angeles as well. Steve Murvine, a well-respected diver from "Sandy Eggo" further south reports the same thing from the waters off La Jolla and Point Loma.
For those of you who thought I'd actually give you the answer to this question, I still need to get that big bucks bequest from the powers that be. I'm not holding my breath, believe me. If you feel so inspired, feel free to send me your donations of a few grand each (not tax deductible) and maybe I'll amass enough to fund the expedition and pay the hand-selected crew. I'm not holding my breath on that, either. Instead, I just booked a flight to Nassau in the Bahamas and plan to spend 10 days there researching bikinis on the beaches... er, I mean filming sharks and efforts to control the invasive lionfish on the coral reefs there. Maybe there will be a few checks in the mail when I get home. I didn't think so.
Image caption: Colorful nudibranchs including Spanish shawl, noble doris, horned aeolid and California blue dorid.
Most of you know Pete Seeger's sad folk song "Where have all the flowers gone?" In it he lamented a chain of actions beginning with young men picking them... everyone... to give to young ladies, who married young men who became soldiers and went off to war returning to be buried in graveyards that became covered in flowers. Whew. Now all you "young" girls know why I "don't bring you flowers any more.
This week my song would be "where have all the nudis gone?" I won't sing it for you because my voice sounds like fingernails on a blackboard even when emanating from my shower. Oh, and the nudis haven't gone to places like Black's Beach in San Diego, Little Beach in Hawaii or Praia do Pinho in Brazil. Nudies go there, not nudis. Shame on you. Regular readers of my column should know that nudis are the often beautifully colored snails without a shell.
Recently I went out on Scuba Luv's King Neptune to dive three island sites looking mainly for squid eggs. I found carpets of them at Hen Rock and Long Point, but only scattered "candles" (the individual egg sacks containing up to 300 eggs each) at Garibaldi Reef. There wasn't a single living squid there... or even a dead one as predators had vacuumed them all up from the bottom. I saw and filmed lots of life on these three dives, but one thing shocked me. Read on.
I've been doing mostly shallow dives above 50 ft in the dive park to maximize my bottom time and gather the most video footage possible to share with you. On these dives I went reasonably deep, up to 114 ft. At those deeper depths I usually encounter lots of nudibranchs in the colder bottom waters... but on this day I saw a total of just one. It wasn't for lack of looking. The one I found, a Chromodoris macfarlandi, was less than an inch long and barely detectable to my aging eyes.
Now where have all the Acanthodoris, the Triopha, the Dialula, the Peltodoris, the Cadlina, the Mexichromis, the Doriopsilla, the Dendronotus, the Flabellina, the Janolus and the Hermissenda gone; not to mention their cousins the Aplysia and Navanax? I don't really expect you to answer that... or even remember the names. It's hard enough for me to do that. Besides, it's MY job to answer these pressing questions of existence!
I noticed that even at these depths, water temperature remains fairly warm for this time of year. The lowest temperature I got during the deeper dives was a balmy 57 degrees. Yes, I know... it sounds cold. But just two years ago it was 52-54 F at those depths and sites. One thing I've noticed is that nudis here, unlike nudies, actually seem to like cold temperatures. Some that are common in the colder mainland waters at shallower depths seem to be missing until one descends to depths below 80-100 ft off Catalina.
My educated guess is that these nudis may actually tolerate warmer water, but their food sources (hydroids, bryozoa, sponges, etc.) may prefer cooler waters. This is what we scientists refer to as an hypothesis. Now if I was well connected, I'd hastily scribble a grant request and get billions of $$$ from the U.S. government to research this question. I'd buy a research vessel, staff it with a lovely (and equally intelligent) bikini-clad crew and sail the ocean blue. Dream on, Dr. Bill.
Given the reality of the situation, I looked for reports from divers in other locations. A friend, Phil Garner, often dives mainland sites like Old Marineland with Merry and another mutual friend, nudi photographer Kevin Lee. They have reported a dearth of dorids and other nudis off "Lost" Angeles as well. Steve Murvine, a well-respected diver from "Sandy Eggo" further south reports the same thing from the waters off La Jolla and Point Loma.
For those of you who thought I'd actually give you the answer to this question, I still need to get that big bucks bequest from the powers that be. I'm not holding my breath, believe me. If you feel so inspired, feel free to send me your donations of a few grand each (not tax deductible) and maybe I'll amass enough to fund the expedition and pay the hand-selected crew. I'm not holding my breath on that, either. Instead, I just booked a flight to Nassau in the Bahamas and plan to spend 10 days there researching bikinis on the beaches... er, I mean filming sharks and efforts to control the invasive lionfish on the coral reefs there. Maybe there will be a few checks in the mail when I get home. I didn't think so.
Image caption: Colorful nudibranchs including Spanish shawl, noble doris, horned aeolid and California blue dorid.
