A few weeks ago I posted a question about an axoltol I had that was
about three to five years old and appeared to be a normal female. Then
all of the sudden I came in one to day this female had changed into a
male (apparently) and had sucessfully spawned. I asked if anyone had ever
seen such a thing before and if it was possible. I got many responses and
the following is a summary of them.
Several people have contacted me with various ideas and proposals re the
apparently sex changing axolotl. Two others have had similar situations
come up where they had wondered if a sex change had occurred but neither
was absolutely sure the animals had not been mixed up. A couple of people
were adamant that there was simply no way the axoltol could change sex.
I had one interesting and quite plausible suggestion. Since we only used
external characteristics to check the sex, the animal in question might
have been a male who was delayed in going through the final steps of
maturation. He merely appeared to be a large female but he was actually a
male. Something (possibly changing homes since this animal came from another
colony) pushed him to go through the final maturation stage and become
sexually active with the typical large male cloaca. Since young axolotls
appear to be all female and secondary sexual characteristics become
visible at highly variable ages this seems to be quite plausible.
All three of the cases I have seen have been a female turning into a male
and never the reverse. Also there are no breeding records of this
particular animal or the other two I observed having previously spawned
as a female. Without any firm literature on the topic, I think we must
leave the possibility of a true sex change as something interesting to
watch for but not in any way known to exist beyond anecdotal reports. A
full documentation would require clear breeding records showing secessful
spawning as a female and then as a male or the reverse.
If anyone has ever had a male to female sex change among their axolotls I
would really appreciate knowing. I would also really like to hear from
anyone who has a well documented sex change.
My thnaks to the 27 people who took the time to respond. My apologies for
not posting the answers sooner.
Natalie K Bjorklund
University Of Manitoba Colony
Winnipeg, Manitoba, Canada