Dive Dry with Dr. Bill

#130 The Boring Treefish

There is a group of fishes that may be one of the most boring I've ever encountered, at least during the day. These are the rockfishes and they include the one I will focus on this week... the treefish. Somewhat secretive during daylight, these yellow and black fish are usually found resting in rock crevices and small caves. They are so boring that I've stopped filming them on my dives because they barely blink on camera, much less do anything really exciting.

Treefish and other rockfish are members of the scorpionfish family. Some scorpionfish in the tropics are deadly poisonous. Fortunately treefish are not. They are found from San Francisco to central Baja, although they are rare north of Pt. Conception. They prefer habitats shallower than 100 feet with plenty of hiding places, but can be found to depths of about 150 feet. The Casino breakwater is perfect since the large rocks offer many crevices, holes and small caves. Here they remain out of sight (except for the keen, albeit aging, eyes of Dr. Bill!).

Adults reach a maximum size of about 16 inches. They are a dull "dirty" yellow (like a "dirty" blonde, and I'm not referring to her language) with a series of 5-6 wide dark bars running vertically. Their lips often appear as if they applied red lipstick a little too liberally, making them look like a blonde whose language might be a little "off color" (or "dirty" if you prefer)!

The young treefish are much more attractive. Their bodies are a bright, clean yellow and the body bands tend to be a darker black. The tips of the pectoral and caudal (tail) fins are often tinged with iridescent blue. In addition to being more photogenic, the young are also much more active than their elders and often swim briskly around their protected niche.

These rockfish tend to be solitary and somewhat territorial. Although generally not aggressive in defending their nook or cranny, they often erect their dorsal fin with its sharp spines if approached by another fish. The red lipstick may also be useful as a warning to other treefish which might attempt to intrude on their turf.

I did encounter one exception to their boring daytime behavior when I encountered two adult treefish interacting. It appeared that they were mating, and showed absolutely no modesty about it at all. The only other occasions I've managed to get interesting footage were when treefish would raise their dorsal fins during threat displays, or when filming the much more vigorous young (ah, why is the energy always wasted on youth?).

As you may have suspected, treefish rest during the day because they are active and feed at other times. They either take the night shift, or work a split shift at dawn and dusk. Imagine having to commute two round trips a day to work. Their food most likely consists of crustaceans like shrimp and crabs, and small fish. Sounds like a fairly healthy diet to me. I wonder if they have to deal with high cholesterol from the shrimp given their generally "rock potato" nature?

As this week's column goes to press, I plan to be diving with my nephew David from Atlanta. He and his sister Kara are visiting this week along with my little sister, Nancy. What a treat to be able to spend time with them and dive with David. He's actually dived more places in the Caribbean than I have! Let's see how he likes a 7mm wetsuit and the cool waters of the California Current. Maybe he'll take me back to Bonaire, Turks and Caycos or some other warm Caribbean dive paradise when he leaves. I'm already packed!

© 2005 Dr. Bill Bushing. Watch the "Dive Dry with Dr. Bill" underwater videos on Catalina Cable TV channel 49, 10:00 AM and 5:00 PM weekdays.

Bright colored juvenile treefish swimming actively (top); adult
treefish with dull colors and doing what it does best- resting.

This document maintained by Dr. Bill Bushing.
Material and images © 2005 Star Thrower Educational Multimedia