Northwest Dive Club

So my wife was asking if Wolfie's just mate seasonally, or do they stick with the same mate? Or is this a one time deal like a gpo or something? I didn't know the answer... does anyone else?

Unlike other fishes they mate for life and the male will vigorously defend his mate and her eggs.

How romantic! My wife will be pleased with that answer!

A rare thing in the underwater world indeed

They do mate and utilize the same dens for protracted periods of time which can be years in some cases. How long depends on the individuals and the opportunities, both for dens and mates. PM me with an email and I can send you an article on a study done by Tony Parra on this for the DIW and Sunrise wolf eels. Tony is a buddy of John Rawlings. I got him to come to one of our meetings once and give a talk on it after John linked me up. There's a lot of great knowledge around here.

Seahorses and many butterfly fish (probably a bunch of others) also have established long term relationships.

Interesting note-they used dye injected into the head to ID the wolfies. For a good while after you could visually see this if you looked carefully.

I'll look forward to reading it...

An ancillary question might be how do you get a wild wolfie to hold still while you inject it's face with dye?

I can't manage to get my domesticated dog to cooperate long enough to give him a bath, and that's painless and on (mostly) dry land.

From the study protocol:

[Tagging Procedure
Individual wolf-eels were identified using two methods; tagging and photographic recognition. To facilitate
tagging, wolf-eels were anaesthetized using a solution of clove oil mixed with equal parts ethanol and
ambient seawater (Munday and Wilson 1997). The anaesthetizing solution was delivered into a wolf-eel
den via a 60 cc catheter syringe and surgical tubing. Initial response by wolf-eels typically involved
retreating deeper into the den, followed by exiting the den as the solution diffused and sedation
commenced. Upon exiting the den, the wolf-eel was restrained in a polyester mesh bag to allow tag
application while minimizing stress to the fish, potential for escape, and injury to the divers. Visible
Implant Elastomer® tags were applied via a 3 cc hypodermic syringe to the anterior portion of the head
(Figure 2) in a unique position and color combination for each individual tagged. Tagged fish were
identified in subsequent dives using an underwater flashlight fitted with an ultraviolet filtered lens.]

Note - If you looked for it you could see this coloration in some individual Wolfies for awhile after. It's long gone now though.

Dusty2 wrote:Unlike other fishes they mate for life....

Not so.

I also had heard this and used to believe that wolf-eels mated for life until I met Marine Biologist Tony Parra years ago, (as Fritz mentioned above), and he disabused me of this notion. I've enjoyed many dives with Tony over the years, and each time I managed to learn something new from him. Here's a quote from the article on wolf-eels that I wrote soon after based on Tony's (and others) research:

"In the past it was regarded as a well-known fact that wolf-eels mated for life. This “fact” was the result of previous studies conducted in aquariums and on casual observations in the wild in which individual fish were not clearly identified with certainty. The new research has revealed that wolf-eels indeed do appear to be loyal mates, but apparently only on a fairly seasonal basis rather than for a lifetime. With some mated pairs, even this does not appear to be an ironclad rule, with the occasional female abandoning the loser of a fight between males to share a den with the victor."

There are many other fallacies out there regarding marine life that everybody seems to "know".

- John