Monday, April 18, 2016

Pond Management Seminar

On Wednesday, April 13, 2016, I attended a Pond Management Meeting in Jesup, Iowa.

The guest speakers were Nate Herman ( ) and his Fish Biologist, Tad Locher.  The speakers were enthusiastic and knowledgable, and I found the presentation to be immensely interesting.  Between information presented and questions I asked before and after the seminar, I feel like a learned quite a bit.

My interest and questions were largely associated with my desire to help the city where I live and fish to manage some of their 30+ public ponds.  Most of the ponds, we'd like to manage to provide good-sized Bluegills.  In a few others, we may want to focus more on managing for good-sized bass.  Some of the things I learned are below.  Some of it, I added some necessary background information as well.
1.  Channel Catfish in ponds:  Channel catfish are a good add-on fish.  They don't seem to adversely affect either the panfish or bass populations.  They are omnivorous, and tend to be more predatorial as they get bigger.   They are an excellent table fish, and are best when harvested at around 1.5 lb size.
They don't typically reproduce well in ponds, so their population should be maintained by balancing stocking rates with harvest rates.

2.  Blue Catfish:  Nate and Tad were VERY excited with the results they've been seeing from stocking Blue Catfish in ponds & lakes.  They are more of a predator than Channel Catfish, and seem to grow faster and larger.  They can reach sizes of 20-25 lbs or more in ponds.  They are good at helping control bluegill and crappie populations, and they will also eat young carp if present.  They typically stock these at a rate of FIVE 8"-10" fish/acre of water.  That seems like a low number, but not when you image them growing to  FIVE 20lb fish/acre!

3.  Hybrid Striped Bass:  Their experience with adding this fish to ponds has been largely good.  They don't do well in some ponds, but do well in others.  They can help control bluegill populations by eating the smaller ones, but won't eat the large ones because of their mouth size.  They typically reach 4-6 lbs in size.  The ponds they do well in often have a good steady supply of water coming in, and/or at least some shad in the pond.  They said there really is no down side to trying Hybrid Striped Bass...if they don't eat well, they just won't grow much.  They recommend stocking of ~ 30 4"-6" fish/acre.

4.  Bluegills:  The most recent studies have shown that if a pond/lake has big bluegills in it, you need to protect the big males that build the nests during spawning.  It works like this:  As long as you have large males doing the nesting/spawning, the younger bluegills will continue to spend their energy on feeding and growing, until they reach the size to be able to compete with those "alpha males".  If those "alpha males" are removed from a pond, the smaller bluegills immediately become sexually mature and their growth rate slows tremendously.  That's commonly how ponds and lakes get "stunted bluegills" that never seem to grow to large sizes. They recommended harvesting female bluegills only.  

5.  Largemouth Bass:  Largemouth Bass have 2 main Roamers (constantly swim around in search of food) and Ambushers (sit and wait for food to swim by a piece of underwater structure).  Roamers eat more bluegills, but expend more they max out at around 3lbs in size.  Ambushers eat fewer bluegills, but expend less energy, so these bass can grow to large sizes.  In waters where large bluegills are the desired goal, you want very little structure, and plenty of bass under 16".  In waters were large bass are the desired goal, you want more structure for ambushing, and you want to harvest skinny bass of any size, but release all fat healthy bass.

6.  Aeration is desired in most ponds.  Actually the "aeration", or pumping air to diffusers placed strategically on the pond bottom, serves to circulate the water column, and when the water from the depths reaches the surface, it will become more oxygenated by contact with the air.  Aeration typically allows an even amount of dissolved oxygen at all depths, and allows fish and bacteria to utilized the entire pond year-round.  Without it, ponds typically stratify during the hot summer months, and water becomes low on dissolved oxygen in the depths.  Inadequate aeration can cause a slow rate of circulation in ponds, which can result in algae blooms and fish kills.

7.  Adding supplemental food (pellets) to ponds can greatly improve fish growth rates and the ultimate size they can obtain.  The type of feed used is important.  For example, bluegills will grow and do well if fed on an omnivorous catfish food pellet.  But they will max out at around 3/4 lb.  If fed a higher protein pellet, they can reach 1.5-2 lbs!  Feeding pelleted food is more economical than feeding minnows.  For example, it takes 10 lbs of fathead minnows to generate 1 additional pound of gamefish biomass in a pond.  It takes 2 lbs of pelleted food to generate 1 lb of additional gamefish biomass in a pond.

8.  If the bluegills in your pond don't seem to grow beyond 4"-6", you can actually help the population by removing some of those fish and stocking 4"-6" bluegills from a hatchery.  This is because the fish in your pond may be 4-8 years old...while the fish from the hatchery are fast-growing fish that are probably only 1.5  years old.  They are likely to outgrow the size of the existing fish in your pond.  This is a good thing!

I thought this was pretty cool....during the presentation, Nate put up a PowerPoint slide showing the differences between a male bluegill and a female bluegill.  I thought the pictures looked really familiar...  so I took a picture of him and the slide to check it out later.
Turns out they are both pictures I took on a flyfishing trip in my kayak at Lake Keomah, Iowa.  I blogged about it here back in 2012.
Yep...pretty cool!  :)  Of all the pictures of bluegills out there....what were the chances???

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