spawn

[Damien]

how long does it normally take for a female to produce eggs inside her??? i caught a nice fish last week and i dont know if it was a female or male it had no sign of a belly but it was on its bed.

[Under the Radar]

how long does it normally take for a female to produce eggs inside her??? i caught a nice fish last week and i dont know if it was a female or male it had no sign of a belly but it was on its bed.

A lot faster than outside  ;D ;D

[Paul Roberts]

Dunno. Seasonally -it takes a full year!

I've been told (by Ralph Manns) that given enough food (for important fat reserves) females can make more eggs and spawn again. But the spawn period is a window that will pass. Bigger deeper waters with different basins of different depths can produce a long spawn period (lake-wide).

As to sexing bass; It's guesswork. Ralph Manns (a biologist specializing in bass) says that no one has found a consistent method. In general, females grow larger than males. Largest, but very rare, males have been known to hit 5lbs..  The only time you can really tell is around during the spawn: by behavior, when females are swollen with eggs in pre-spawn, and post-spawn when they are hollow bellied.

[Catt]

I'm not sure what the gestation period of a female bass is; maybe Raul our resident veterinarian can shed some light on this subject.

[Sam]

Males guard the bed.

So you probably saw a male guarding the bed.

[Paul Roberts]

I think I can handle the gestation period question. Fish don't really have an internal "gestation period" like mammals do. Fertilization occurs outside the body and embryo development rate is determined by temperature (eggs hatching in about a week in most circumstances).

Now egg maturation within the female, what Catt, and maybe Damien, is getting at , is a different thing. With spring spawners it begins the previous year, with immature eggs appearing in the ovaries in the autumn. They then develop slowly (in the south), or enter a nearly complete hiatus (in the north), during winter. In the late winter/early spring there is a surge of hormones coupled with increasing temperatures that bring on maturation.

Final timing is a combination of factors: An endogenous rhthym (internal clock; apparently set the previous year), temperature (known to be critical for egg survival), and other stuff I've listed in another recent post.

In the upper latitudes where I've fished and observed, calendar dates seem to be most useful, coupled with water temperature trends to fine tune by a week or so. The bulk of the spawn seems to be pretty consistent where I've fished, falling within a week (either side) of a specified week -i.e. I expect the Colorado spawn in my small shallow ponds to fall around the first of May. However, deeper (colder) waters fall later -as much as a month in the deepest ones.

Hope this helps.