DIVE DRY WITH DR. BILL #885: BITE ME!
People often ask how I can still dive after 58 years on SCUBA. "Haven't you seen it all by now?" they ask. Of course with my advancing age, I can barely remember what I saw on yesterday's dive so it's all new to me each day. But seriously, even though I've done thousands of dives in Catalina waters, I still see new behaviors and occasionally new species that keep me going. It would take a hundred lifetimes to learn "everything" about our kelp forest ecosystems.
Some time ago, I once again observed a behavior I don't believe I've ever seen before. I was cruising along in the shallows looking for abalone to feed when I stopped a few feet from two small (~7 inch) kelp bass (Paralabrax clathratus), also known as calico bass. Now this species is one of the most common fish in the dive park so I thought I'd seen it all, but no...
These two fish were mouth fighting, opening their mouths wide and threatening each other at close distance (a silly centimeter or two)! Sometimes when they'd break, one would nip the other on the body. This went on for nearly five minutes as I watched from three feet away (alas, with no camera). Then a third, and larger, kelp bass joined the fray and engaged in a brief episode of mouth fighting.
Another common species in the dive park, the California sheephead (Semicossyphus pulcher), is well known for its ritualistic mouth fighting. Males threaten other males to establish dominance for territory and a harem of lovely ladies. In fact the females will even engage in mouth fighting with other females. I've even seen the youngsters (2-3") do it as well. On occasion I've observed an adult male winner in the competition nip its defeated rival.
Of course fish don't have arms and boxing gloves wouldn't fit well on their pectoral fins, so the mouth is one of the few weapons they can employ in combat. But then Mike Tyson decided to use his mouth in a boxing match. I wonder if he is part fish? At least with the fish it is largely ritualized and actual harm rarely befalls the loser (other than the ignominy of defeat).
Years ago I was flabbergasted when I observed and filmed halfmoon (Medialuna californiensis), also erroneously called Catalina blue perch (they are sea chubs), engaged in such combat. Individuals would literally lock lips (sigh, I used to do that with my girlfriends) and literally try to body slam their rival. That was quite surprising since they are generally well behaved in "schools" and never sent to the principal's office. Sadly my video camera malfunctioned and the footage I took came out badly over-exposed.
Kelp bass are often overlooked by divers since they are so common... unless they are spearos and are looking for a tasty dinner. And thanks to the snorkelers feeding them frozen peas, they often bite divers' hands! What self respecting kelp bass would go to Vons to buy a bag? I'll admit I don't pay these fish a lot of attention. They are good at signalling when an octopus is nearby since they gather and point to the cephalopod. However, they are a critical component of our ecosystem and are worthy of closer study.
As an ecologist, I don't focus on a single species, or even an entire family, order or phylum of marine critters. All species matter in a healthy ecosystem. My job is to try to understand the interactions of all the inhabitants of our kelp forests. Now that is a daunting task, but its breadth keeps me diving well into my "mature" years in the never-ending quest to understand our underwater world.
© 2020 Dr. Bill Bushing. For the entire archived set of nearly 900 "Dive Dry" columns, visit my website Star Thrower Educational Multimedia (S.T.E.M.) Home Page
Image caption: Kelp bass staring me down and two youngsters facing off; halfmoon and adult male sheephead; female and young sheephead.
People often ask how I can still dive after 58 years on SCUBA. "Haven't you seen it all by now?" they ask. Of course with my advancing age, I can barely remember what I saw on yesterday's dive so it's all new to me each day. But seriously, even though I've done thousands of dives in Catalina waters, I still see new behaviors and occasionally new species that keep me going. It would take a hundred lifetimes to learn "everything" about our kelp forest ecosystems.
Some time ago, I once again observed a behavior I don't believe I've ever seen before. I was cruising along in the shallows looking for abalone to feed when I stopped a few feet from two small (~7 inch) kelp bass (Paralabrax clathratus), also known as calico bass. Now this species is one of the most common fish in the dive park so I thought I'd seen it all, but no...
These two fish were mouth fighting, opening their mouths wide and threatening each other at close distance (a silly centimeter or two)! Sometimes when they'd break, one would nip the other on the body. This went on for nearly five minutes as I watched from three feet away (alas, with no camera). Then a third, and larger, kelp bass joined the fray and engaged in a brief episode of mouth fighting.
Another common species in the dive park, the California sheephead (Semicossyphus pulcher), is well known for its ritualistic mouth fighting. Males threaten other males to establish dominance for territory and a harem of lovely ladies. In fact the females will even engage in mouth fighting with other females. I've even seen the youngsters (2-3") do it as well. On occasion I've observed an adult male winner in the competition nip its defeated rival.
Of course fish don't have arms and boxing gloves wouldn't fit well on their pectoral fins, so the mouth is one of the few weapons they can employ in combat. But then Mike Tyson decided to use his mouth in a boxing match. I wonder if he is part fish? At least with the fish it is largely ritualized and actual harm rarely befalls the loser (other than the ignominy of defeat).
Years ago I was flabbergasted when I observed and filmed halfmoon (Medialuna californiensis), also erroneously called Catalina blue perch (they are sea chubs), engaged in such combat. Individuals would literally lock lips (sigh, I used to do that with my girlfriends) and literally try to body slam their rival. That was quite surprising since they are generally well behaved in "schools" and never sent to the principal's office. Sadly my video camera malfunctioned and the footage I took came out badly over-exposed.
Kelp bass are often overlooked by divers since they are so common... unless they are spearos and are looking for a tasty dinner. And thanks to the snorkelers feeding them frozen peas, they often bite divers' hands! What self respecting kelp bass would go to Vons to buy a bag? I'll admit I don't pay these fish a lot of attention. They are good at signalling when an octopus is nearby since they gather and point to the cephalopod. However, they are a critical component of our ecosystem and are worthy of closer study.
As an ecologist, I don't focus on a single species, or even an entire family, order or phylum of marine critters. All species matter in a healthy ecosystem. My job is to try to understand the interactions of all the inhabitants of our kelp forests. Now that is a daunting task, but its breadth keeps me diving well into my "mature" years in the never-ending quest to understand our underwater world.
© 2020 Dr. Bill Bushing. For the entire archived set of nearly 900 "Dive Dry" columns, visit my website Star Thrower Educational Multimedia (S.T.E.M.) Home Page
Image caption: Kelp bass staring me down and two youngsters facing off; halfmoon and adult male sheephead; female and young sheephead.
