I felt like this was a good time to post some info on FHM and their spawning behavior. Many recent postings leave the impression FHM have spawned "once or twice" now. I will try not to drag this out so bare with me here.
First, FHM become sexually mature fairly quickly at an intermediate size-not just as 3 to 3-1/2" adults. Males are slower to mature than females for a reason.....stress or lack of. Males begin cleaning rock, wood, pvc pipe or actually about anything intersecting the basin.
He attracts females to continually lay eggs in his spot. He guards, cleans and hatches daily until death.
The part that is sometimes hard to understand is the frequency of the spawn as a group. They do not actually spawn as a group, they spawn as individuals which means there are females laying eggs every minute of the day when water temps rise and they are triggered to spawn. Every minute of every day for the summer months-generally. When this is happening, keep in mind there are eggs hatching every minute of every day, throughout the summer. Every day the FHM are growing in numbers substantially higher than mortality.
In a fertile environment the first 30-60 days of hatchlings can become sexually mature and begin the cycle the same as the original adults did-in the same year they hatch. This is a part of the reason starting in a new pond it is not necessary to pile an outlandish number of minnows to start, in fact it's best if you start with a lower number so the forage (planktonic in nature) available to the new hatch is not removed too quick-fertilization is important here, or having the nutrient load available to grow the single cell organisms that start this cycle.
I have seen several project beginnings with my own eyes where the FHM and GSH have started to appear very lean due to a lack of fertility. A fish eating 100 skinny minnows is getting far less return than a fish eating 50 fat, healthy minnows because that fish done twice the work for the same useable consumption so the higher the reproduction, the more fry, the quicker this can occur, creating a problem that is not easily corrected. To add to that, it's not always practical for some pond owners to fertilize at the right times with the right products simply because "they didn't know". We hope they all find PondBoss to gain the knowledge needed, but we've all seen that at some point because we didn't know what we didn't know...
I hope this makes sense and isn't misleading to anyone, I have just noticed several posts this spring about FHM that waved a flag for me. Hope this is useful to some.