Pond Boss Forums INTRO Questions & Observations Paddlefish for Control of Filamentous Algae?

Crazy FishinRod question of the month to follow:

I looked up the paddlefish (aka spoonbill) record for Kansas yesterday, and was shocked to see that the record 144# fish came from a pond, rather than from a sluggish Kansas river.

Paddlefish are filter feeders with gill rakers - similar to tilapia.

The literature suggests they don't "do well" in environments without moving water, but also says that they need moving water to spawn. So I don't know if "don't do well" actually means failure to thrive, or failure to reproduce?

In my experience, ponds in Kansas during the summer have HEAVIER planktonic blooms for filter feeders compared to moving water.

1.) Not considering the supply logistics, would a couple of large paddlefish in a pond filtering out the planktonic food supply ALSO filter out a lot of the filamentous algae?

2.) Considering the problem of obtaining the fish, it is legal to snag them in a few designated locations in Kansas and I believe the only prohibition is transporting them over state lines for caviar purposes. However, I believe they are a totally protected species in some other states.


Comments speculating that paddlefish might actually be a tool for FA control, or help clear the water in a pond primarily used for swimming, as well as comments regarding the ridiculousness of the idea would all be welcome!

Rod, I overlooked this post. I'm guessing that nobody has ever tried that.

Considering their growth potential and the fact that they don't feed on other fish I would think that would work if they consume FA.

I don't see anything in the Oklahoma regulations prohibiting it but know it's not recommended to stock from other water supplies.

Google says this They are not known to actively consume filamentous algae as part of their diet. However, filamentous algae can sometimes be present in the environments where they feed, and they may incidentally ingest small amounts while filtering for plankton. If you're looking for fish that specifically target filamentous algae, species like Siamese algae eaters, mollies, and Florida flagfish are more effective choices

Funny that it doesn't recommend Tilapia.

After more research, the fish recommended are only fish typically used in Aquariums.

Paddlefish have lived and grown (perhaps slowly) without moving water in our ponds. (Unless the osprey has intervened) we currently have two. Our previous paddlefish grew from about 1 ft to about 3 ft before succumbing to a fish kill.

How large is your BOW and what's the stocking ratio of each species? I have seen some pictures of your massive BGXRES. Are they in the same pond?
Due to their size do you think there's any need to be concerned about the amount of Plankton they consume that the BG and other species could be consuming?

We have a 1/2 acre pond and a 2/3 acre pond, with one Paddlefish stocked in each. (Truly a big time Paddlefish operation. ) Given that density it is hard to notice any impact.

We have them just for the variety. They are the only fish my wife claims as her own.

Thanks, Theo.

I didn't think they would eat enough algae to make a significant dent, compared to an entire population of tilapia that still has to work hard to make a dent!

However, does your wife enjoy HER fish? Do you observe her fish cruising around the pond occasionally?

I doubt I will ever have the opportunity to stock any, but that it would be a good conversation starter to have a couple in the swimming pond.

Where do you get paddlefish for stocking? I'd throw a few in pond in a heartbeat.

^^^ Nevermind. A quick Google search found as many as I'm willing to pay for.

Since I've retired, I'm not sure she enjoys anything.

I'm not sure we've ever seen any of them swimming around. But I heard about it when the first one died.

I thought I had seen paddlefish (a while back) in the "fish listings" for some suppliers.

I assume they wouldn't stock them if they didn't have some reason to tell pond owners how they would provide a benefit to the pond?

Do paddlefish stir up the bottom to filter feed, or do they just cruise through the water column and actually clear things up?

I have seen oxbows of rivers that stayed murky for weeks after any floodwaters entered. They were full of trash fish, such as carp, buffalo, suckers, and drum. I don't know which of those stir the water the most, but some fish were keeping that water constantly churned!

Here's a link to a place that raises them a couple towns over from me (southern OH). Not sure on how they do with algae control, but looks like they stock their farm ponds/lakes at 10-20 fish per acre.

https://www.bigfishfarms.com/about

Conservation Efforts and Regulations

"Recognizing the vulnerability of paddlefish populations, Texas enacted protective measures in 1977, designating them as a threatened species. This status makes it unlawful to catch, kill, or harm paddlefish in Texas. The intention behind this protection is to allow the population to recover and thrive in its natural environment."

https://enviroliteracy.org/are-there-paddlefish-in-texas/

Unlawful to catch one. Need to explain that one to the fish

The Mo conservation dept. stocked some in a friend of mines ponds and left them in there for ten yrs, I believe, then they came back and harvested them for the eggs for hatching in their hatcheries and restocking several state bodies of water.

Might be worth looking in to.

My research and readings indicate that paddlefish almost exclusively eat larger zooplankton of sizes 200 -1000 um (0.20 – 1.0mm or 0.0078 – 0.0393”) and not algae. See below. Note – Immature stages of Crustacean zooplankton consumed are often greater than 150um. However there are many other types of zooplankton including rotifers and protozoans present in the zooplankton community less than 200um. Paddlefish are able to uniquely locate and strain out mainly larger zooplankton of Cladocerans and or Copepods depending on seasonality. When available they will strain out small stages of insect larvae and fish fry. Feeding methods also cause them to at times inadvertently ingest up to 50% of their gut content as very small sand grains and detritus particles strained from the water column .

Because paddlefish gather food by methods of filtering – straining the water, the long strands of filamentous algae IMO are rarely if ever eaten because these spaghetti like strands and mats would plug, clog and become entangled in their physical feeding mechanisms and process. Thus their feeding mechanisms are very counter- productive for eating FA.

Planktonic food items will be highly dependent on the types of plankton endemic to each water body.
Reference Notes – “Our study supports the argument that paddlefish do not selectivity feed and can be described as indiscriminate feeders.”
One example food items:
From one of the referenced articles below, they identified seven different taxonomic groups in order of most abundant prey items: Copepoda, Cladocera, Insecta, Ostracoda, Amphipoda, Decapoda, and diatoms (Table 2). Amphipods and decapods (bottom living crustaceans) were rarely found in paddlefish stomachs.
Study Note- It is possible that the importance of algae in the diets of subadult and adult paddlefish has been underestimated. We found that diatoms (are non FA algae) dominated the stomachs of Louisiana paddlefish in May 2003. This is similar to other southern rivers where Hageman et al. (1986) found “prominent green masses of algal and/or plant cells” in one particular month (October). (Note many forms of larger unicellular and colonial soft bodied algae would not be readily identifiable in gut contents). Although few studies have reported algae as a diet item, some paddlefish populations apparently do consume algae during certain times of the year. IMO probably due to the common preponderance of seasonal types of usable sizes of planktonic algae.

Note – IMO fish that normally do eat filamentous algae (FA) do not gather FA by filter feeding and use a different feeding mechanism or method.

https://fisheries.org/docs/books/54066P/4.pdf
https://fisheries.org/docs/books/54066P/1.pdf

Thanks Bill!

The important and relevant data that you list is NOT available in the average internet article for "paddlefish feeding habits". Sure is nice to get some actual professional input.