DIVE DRY WITH DR. BILL #595: THE "BASS" ARE BACK
Last weekend I had a chance to vastly improve my giant sea bass (GSB) count for the year. Because I dive mostly at night this time of year to avoid the crowds, I had yet to see a single giant sea bass (Stereolepis gigas) in our waters this year. Even when I dive during the day, I have my eyes glued to my high definition camera's viewfinder looking down on the reef and probably wouldn't realize it if a giant sea bass (or a great white for that matter) was looking over my shoulder. Earlier this year, Dr. Larry Allen, head of the biology department at Cal State Northridge (CSUN) and a noted fish expert, contacted me regarding studies his graduate students were doing on the giant sea bass. He asked for my input and suggested I dive with them this summer. How could I resist the opportunity?
Saturday was the day. Larry called to say CSUN's research vessel, the R/V Yellowfin, was steaming south toward Avalon from the Isthmus and they would send a skiff in to pick me up at the Pleasure Pier. Fortunately it was the day of the World Cup consolation match so I could forego watching soccer for one day. When the Boston whaler arrived, I loaded my dive gear on board and we headed out to the Yellowfin off the harbor mouth. Once on board, we gathered to discuss the day's diving. One group would dive off the skiff on the backside of the island while the group I was to dive with would check out Blue Car Wreck north of the East End Quarry Two years ago when I was filming the documentary for NHK (Japan's public TV station) with the team from Japan Underwater Films, we had great luck (and great visibility) at that site.
While the R/V Yellowfin did some acoustic data collection, my group submerged off the Boston Whaler. The visibility was great. It wasn't long before we spotted four giant sea bass swimming over to check us out. Now I always dive with my camera, but this time I elected to leave it at home. Not a wise choice as one of the GSBs swam over to me and gave me the eye, then circled me. I think it finally recognized I was not a suitable mate and swam on, but it would have given me an opportunity to get some great footage! Our support boat was flying the diver down flag, but it seems some of the weekend warriors who bring boats out to Catalina have little clue what the flag means. We had a power boat go almost overhead in shallow water. I suggested limpet mines might be more effective than the dive flag.
After a lunch break and some discussion, we were off to Twin Rocks for the second dive. This is another location where we had great luck filming the NHK special and divers have been seeing GSBs on almost every trip. My thoughts on this are that the large mating aggregation that used to gather at nearby Italian Gardens got tired of all the divers interfering with their nuptials and moved further up the coast. I've seen this happen at other sites where GSBs were abundant in years past. Although water conditions weren't as stellar here as at Blue Car Wreck, we soon had a group of six GSBs swim past us all in a line. It is still early in their courtship and the fish often have not paired off and don't hover in one place as they do later in the summer. It is pretty standard to see them swimming from one place to another, giving us less time to study them. Ever try to outswim one of these giants? Good luck!
By the way, these huge fish are not "bass," or even seabass but members of the wreckfish family. Larry's group has made some interesting discoveries about the GSBs, but I won't reveal their secrets until they publish them in a scientific journal. However, one very interesting piece of data came from the use of a laser "measuring stick." By positioning the fish within the two ends of this device and sending out a laser pulse to measure distance, one can mathematically determine the length of the fish. I've had a running "debate" with another long-time diver who claims the GSBs today are much smaller than divers have reported. He has based this on his days as a spearfisher decades back, and on historic photos showing GSBs in the 200-400 lb range next to human anglers in the 1890s and early 1900s. Of course people were smaller way back then. He doubts that fish today are larger than 400 lbs, but many of us have seen GSBs we estimate at up to 600 lbs and 7 1/2 ft in length. One fish measured by the CSUN grad students came in at NINE FEET and, if accurate, this fish must have weighed about 800 lbs (the upper limit of their reported historic weight).
As a solo diver, I believe in having backups of safety gear. For that reason, I dive with two computers so if one fails or the battery goes dead I still have one to tell me my depth, dive time and how close I am to requiring decompression. My backup computer had died on me two dives ago, but I still had my primary one so I had no worries doing these two dives. Little did I expect that this computer's battery would suddenly fail on the first dive. I made both dives without any information as to my depth, dive time or proximity to decompression. I had little choice but to make the dives, but it was a bit unnerving. Then when I surfaced following the second dive, my backup computer's battery compartment had flooded. That was a total shock because I had tried changing the battery, but had no luck getting the battery cover off a few days earlier. On the dive, it just fell off. Go figure. Hopefully that computer will still work once I get a new battery for it.
On the way back from our last dive, the R/V Yellowfin stopped off Toyon, my home for the first 10 years of my life on the island (1969 to 1979). It's always good to get a look at my old marine biology lab by the pier and the apartment I called home. However, we were in 200 ft of water and the guys had stopped to do some fishing. When they started pulling up sanddabs, I checked out where we were and the boat was sitting over the old sanddab hole I used to fish in the early 1970s when the school dining hall was closed for the summer and I had to provide my own food. Looks like that hole is still producing. We also pulled up a few rock cod, and their swim bladders had pushed their tongues and eyes out due to the reduced pressure in shallow water. The team had an interesting device that allowed an angler to lower the fish back in and release it at depths up to 150 ft. That way the fish could survive a plunge back to depth and live another day. Based on survival studies, the device works. Pretty cool. The crew was thinking how big one would have to be to drop a GSB back to depth. Of course you'd need a lot more weight on it to do that!
Over the last two decades I've seen a fair number of giant sea bass and filmed so many I hesitate to gather more footage of them. However, on this fishing interlude one of the anglers captured something I'd never seen off Catalina... a sarcastic fringehead (Neoclinus blanchardi). Although my mainland dive friends see this species in relatively shallow water, in all my 45 years of diving Catalina I had never seen one here! This was a first. Since we were fishing in 200 ft of water, Larry thought it might be a new depth record for the species but after doing a little research he discovered it had been reported down to a maximum depth of 200 ft. I guess this little fringehead knew its limits!
Image caption: The R/V Yellowfin research vessel, giant sea bass posing for me when I had my camera and a sarcastic fringehead male (image courtesy of Kevin Lee)
Last weekend I had a chance to vastly improve my giant sea bass (GSB) count for the year. Because I dive mostly at night this time of year to avoid the crowds, I had yet to see a single giant sea bass (Stereolepis gigas) in our waters this year. Even when I dive during the day, I have my eyes glued to my high definition camera's viewfinder looking down on the reef and probably wouldn't realize it if a giant sea bass (or a great white for that matter) was looking over my shoulder. Earlier this year, Dr. Larry Allen, head of the biology department at Cal State Northridge (CSUN) and a noted fish expert, contacted me regarding studies his graduate students were doing on the giant sea bass. He asked for my input and suggested I dive with them this summer. How could I resist the opportunity?
Saturday was the day. Larry called to say CSUN's research vessel, the R/V Yellowfin, was steaming south toward Avalon from the Isthmus and they would send a skiff in to pick me up at the Pleasure Pier. Fortunately it was the day of the World Cup consolation match so I could forego watching soccer for one day. When the Boston whaler arrived, I loaded my dive gear on board and we headed out to the Yellowfin off the harbor mouth. Once on board, we gathered to discuss the day's diving. One group would dive off the skiff on the backside of the island while the group I was to dive with would check out Blue Car Wreck north of the East End Quarry Two years ago when I was filming the documentary for NHK (Japan's public TV station) with the team from Japan Underwater Films, we had great luck (and great visibility) at that site.
While the R/V Yellowfin did some acoustic data collection, my group submerged off the Boston Whaler. The visibility was great. It wasn't long before we spotted four giant sea bass swimming over to check us out. Now I always dive with my camera, but this time I elected to leave it at home. Not a wise choice as one of the GSBs swam over to me and gave me the eye, then circled me. I think it finally recognized I was not a suitable mate and swam on, but it would have given me an opportunity to get some great footage! Our support boat was flying the diver down flag, but it seems some of the weekend warriors who bring boats out to Catalina have little clue what the flag means. We had a power boat go almost overhead in shallow water. I suggested limpet mines might be more effective than the dive flag.
After a lunch break and some discussion, we were off to Twin Rocks for the second dive. This is another location where we had great luck filming the NHK special and divers have been seeing GSBs on almost every trip. My thoughts on this are that the large mating aggregation that used to gather at nearby Italian Gardens got tired of all the divers interfering with their nuptials and moved further up the coast. I've seen this happen at other sites where GSBs were abundant in years past. Although water conditions weren't as stellar here as at Blue Car Wreck, we soon had a group of six GSBs swim past us all in a line. It is still early in their courtship and the fish often have not paired off and don't hover in one place as they do later in the summer. It is pretty standard to see them swimming from one place to another, giving us less time to study them. Ever try to outswim one of these giants? Good luck!
By the way, these huge fish are not "bass," or even seabass but members of the wreckfish family. Larry's group has made some interesting discoveries about the GSBs, but I won't reveal their secrets until they publish them in a scientific journal. However, one very interesting piece of data came from the use of a laser "measuring stick." By positioning the fish within the two ends of this device and sending out a laser pulse to measure distance, one can mathematically determine the length of the fish. I've had a running "debate" with another long-time diver who claims the GSBs today are much smaller than divers have reported. He has based this on his days as a spearfisher decades back, and on historic photos showing GSBs in the 200-400 lb range next to human anglers in the 1890s and early 1900s. Of course people were smaller way back then. He doubts that fish today are larger than 400 lbs, but many of us have seen GSBs we estimate at up to 600 lbs and 7 1/2 ft in length. One fish measured by the CSUN grad students came in at NINE FEET and, if accurate, this fish must have weighed about 800 lbs (the upper limit of their reported historic weight).
As a solo diver, I believe in having backups of safety gear. For that reason, I dive with two computers so if one fails or the battery goes dead I still have one to tell me my depth, dive time and how close I am to requiring decompression. My backup computer had died on me two dives ago, but I still had my primary one so I had no worries doing these two dives. Little did I expect that this computer's battery would suddenly fail on the first dive. I made both dives without any information as to my depth, dive time or proximity to decompression. I had little choice but to make the dives, but it was a bit unnerving. Then when I surfaced following the second dive, my backup computer's battery compartment had flooded. That was a total shock because I had tried changing the battery, but had no luck getting the battery cover off a few days earlier. On the dive, it just fell off. Go figure. Hopefully that computer will still work once I get a new battery for it.
On the way back from our last dive, the R/V Yellowfin stopped off Toyon, my home for the first 10 years of my life on the island (1969 to 1979). It's always good to get a look at my old marine biology lab by the pier and the apartment I called home. However, we were in 200 ft of water and the guys had stopped to do some fishing. When they started pulling up sanddabs, I checked out where we were and the boat was sitting over the old sanddab hole I used to fish in the early 1970s when the school dining hall was closed for the summer and I had to provide my own food. Looks like that hole is still producing. We also pulled up a few rock cod, and their swim bladders had pushed their tongues and eyes out due to the reduced pressure in shallow water. The team had an interesting device that allowed an angler to lower the fish back in and release it at depths up to 150 ft. That way the fish could survive a plunge back to depth and live another day. Based on survival studies, the device works. Pretty cool. The crew was thinking how big one would have to be to drop a GSB back to depth. Of course you'd need a lot more weight on it to do that!
Over the last two decades I've seen a fair number of giant sea bass and filmed so many I hesitate to gather more footage of them. However, on this fishing interlude one of the anglers captured something I'd never seen off Catalina... a sarcastic fringehead (Neoclinus blanchardi). Although my mainland dive friends see this species in relatively shallow water, in all my 45 years of diving Catalina I had never seen one here! This was a first. Since we were fishing in 200 ft of water, Larry thought it might be a new depth record for the species but after doing a little research he discovered it had been reported down to a maximum depth of 200 ft. I guess this little fringehead knew its limits!
Image caption: The R/V Yellowfin research vessel, giant sea bass posing for me when I had my camera and a sarcastic fringehead male (image courtesy of Kevin Lee)
