Thread: Ask the Biologist

No offense taken, Cnote.

I hope he has some ideas because I really like that lake.

Originally Posted by PK Buggers

Hey Craig,
Sumpthin I was always wantin to ask, how much does the full moon effect the crappie(and other fish for that matter) spawn? Is there something too the full moon influence or is it more water temperature dependent?
Thanks, PK

PK,

Photoperiod (length of daylight) and water temperature will play a larger role in timing of the spawn. Moon phase may also play a role or may improve fish activity during the nighttime hours (walleye activity for instance) but I don't have any hard data on this. Some fish, like white bass or paddlefish, need runoff or inflow events to kick their spawns in to high gear as they run up river to spawn. In short, I would focus on photoperiod (which is tied to time of the year) and water temperature for tracking the spawn of my favorite fishes.

Originally Posted by sah

Craig,
I caught a few crappie the other day and the larger one's eggs were mushy and had little to no blood in them, some of the smaller one's eggs were more firm and had more blood showing. I was wondering which one's were farther along and would lay egg's first.

sah,

It's difficult to predict when a fish will be spawning by looking at the eggs but as a general rule of thumb, the larger the individual eggs are the closer to spawning the fish is. Fish may have more more or less blood vessels in the ovaries just due to variation amongst individuals. Softer ovaries that are brighter yellow/orange with larger sized eggs are likely very close to spawning. Since crappie (and most other Kansas fish) are already preparing for the spawn in mid-fall months, they carry these eggs for a large part of the year so anglers may see a wide range of egg development if they fish throughout most of the year. From my experience with walleye, a fish can go from "green" (not ready to spawn) to "ripe" (ready to go!) in a matter of hours. Crappie are intermittent spawners and may spawn some eggs at one time and additional eggs at a later time so not all eggs may have similar appearance in the ovaries.

Thanks for your insight, Craig.

Originally Posted by Fish Taxi

Hi Craig,
I got into a discussion the other day about Lake Wabaunsee's crappie population, and would like to get your perspective.

A group of anglers was discussing the reasons why the lake contains so many small crappie. One person's theory was that it gets over fished and whenever a crappie reaches filleting-size, it hits the frying pan. Another guy's theory was that it is overpopulated and the fish are stunted.

I think both theories seem plausible.

I believe it probably does get a bit over-fished because I know of a few guys that take out boat-loads of crappies, and it gets pretty crowded with boats for a lake that's only 200 acres. There are a couple of locals that brag about how they cleaned 2000+ crappies last year and I believe them because I have fished beside them and seen how everything goes into the livewell...

I think the theory about it being overpopulated is also pretty reasonable. I sure seem to catch a lot of skinny crappie out there. It is nothing to get into a school of paper-thin 8" crappies and sit and hook them for hours. They can black-out the fish finder at times. Whenever I do catch a 10"+ crappie (about every tenth fish), it is also skinny compared to a crappie from Tuttle, Council Grove, Banner Creek, or pretty much anywhere else I can think of.

Recruitment is pretty good (I imagine) because the lake is always stable and the crappie's nests are well protected by the countless docks that line the shore. And I also have to wonder if there are enough big predators to keep the numbers of small fish in check. I think most of the anglers are throwing back bass, but the good saugeye and catfish almost always end up as someone's dinner.

So, the million dollar question(s)... From a biologist's perspective, can you explain what is going on with the crappie population in Lake Wabaunsee? And can you please tell me what, as an angler and resident, can I do to help the crappie population get bigger and fatter? Should I throw back all saugeyes and walleyes? Should I start filleting 8" crappies and throw back the 10" ones? Should I compliment the guys who are cleaning 2000+ crappies each year or encourage them to throw some back?

Thank you for taking the time to read this, and I am looking forward to your response.
Chris

Chris,

I have forwarded your question on to the KDWP fish biologist that oversees Lake Wabaunsee. I could "speculate" all day on what "might" be up with this particular crappie population but it would be better to get good information from fish sample data taken over the years. I will let you know what I hear back from Ely.

Originally Posted by cnote

Fish Taxi,
Not trying to high jack your question or pretend that I know more than a biologist, but I was wondering the same thing. I talked to my sister-in-laws husband who has a duck/fishing lease and he had the same issue, tons of small crappies. We'd go duck hunt then catch 50-100 crappie, keep them all. The last few years he's been catching a 5 gallon bucket full and keeping them all. We went duck hunting/fishing around Christmas and you could tell it's paid off. The crappie are finally getting some size to them, but he also has catfish and bass in the same lease. I'll be interested to see what the answer is from somebody who knows. But they also don't have a length limit and a 50 creel limit at Wabaunsee, makes me think they have a bunch that need thinned out, which I'm more than willing to do my part if that is what it takes.

Cnote,

Crappie can be small for a number of reasons. They may be young fish resulting from a very productive spawn that seems to overpower the rest of the larger fish in the lake causing very high "dink" to keeper ratios. The crappie may be stockpiled and slow growing (stunted) as a result of turbid water reducing predation, too much vegetation inhibiting predation, predator population out of balance causing reduced predation on the crappie, or just no predators available in the lake. If angler harvest is too high, then the crappie won't live long enough to reach the larger sizes. There may be many reasons for small crappie and sometimes the reasons are not very obvious.

Fish biologists use fish sample trend data, age and growth information, angler catch/harvest information from creel census, and other info to formulate management plans on managed waters. The "big picture" is more easily seen when you have usable data available.

It's difficult to pinpoint the reason for small crappie in a water body with only a small bit of info, but a pond/lake owner can take note of current and past conditions to get an idea of what is going on there with their crappie populations.

Hopefully you will be able to get some good info when I post the reply to the status of Wabaunsee.

I'm familiar with the "cliff's notes" version of how the crappie spawn works, but I was curious if you could tell me more details about their behavior. I know the males select a site, "build" a nest and guard it. The females deposit eggs which are fertilized by the males, and then the males guard the nest until the eggs hatch and also guard the young for a few days. (according to what I read on the internet.:D)...

Just wondering??? Is there any kind of courtship? How does a female decide which male's nest to use. Do multiple females deposit eggs in one male's nest? Do females deposit eggs in multiple males' nests? What kind of behavior do the males do to attract females? How do they get "on the same page" so they synchronize their spawning actions? Just curious.

I googled the heck out of this, but didn't find much useful information.

The reason for the question is that I am working on a taxidermy project and would like to make it more artistic than the usual "banana-shaped fish on a board". I want to accurately display several pre-spawning crappie in a natural way. Any help would be appreciated. Thanks Craig.

P.S.
I realize the rest of you guys are probably fighting the urge to crack some perverted jokes since we are all 12 years old at heart. I won't be offended if you hijack my post... as long as I get the correct answer at some point.

FishTaxi: I used to go scuba diving and snorkeling in the spring to observe crappie spawning, it was pretty fascinating to watch. The males would hover above the nest at about a 45° angle (sometimes they would be nearly vertical) and fan the gravel with their tail to make a crater like depression. If you can find some water with visibility greater than five or six feet I would recommend checking it out. It happens in shallow enough water that a snorkel and mask is all you need (and a wet suit unless you enjoy being chilled to the bone).

At times the males would be so aggressive they would even attack me if my approach was too close. I remember one occasion wherein a large male bit me on the lip, it was actually somewhat painful and left a scratch. I backed off and took a moment to appreciate the irony.