Pond Boss Forums INTRO Questions & Observations Comments wanted on using a rot basket.

I would/will use this system once I have a pond.

What I got from the article I posted is not to use birds if there is a large number of them dead from an unknown cause. Also I probably wouldn't use dead fish from my own pond just to be safe.

I just finished reading an article I had set aside while researching maggots as fish food. I still would probably utilize a rot basket for feeding fish, but given what I just read I would definitely avoid using any birds as a medium, especially waterfowl.

One of the most interesting points this article makes is that avian botulism is anything but rare.

Here are a few excerpts from the article:

"During the last century, avian botulism killed many millions of
birds, especially waterfowl and shorebirds, and was the most
significant disease of waterbirds in total mortality. Large
outbreaks of “duck sickness”, later recognized to be type C botu-
lism, were first documented in the western USA and Canada in
the early 1900s (Hobmaier 1932)."

"More than a million deaths from
type C avian botulism have been reported during single
outbreaks in some wetlands in North America and Russia (Table
1), and outbreaks with losses exceeding 50 000 birds have been
relatively common. Even though most of the large outbreaks of
avian botulism occurred in North America, the global impor-
tance of the disease and its potential to cause massive and even
catastrophic losses of birds are evident."

"Birds that sift through the mud to feed, such as Mallard and
other dabbling ducks, and filter feeders, such as Northern
Shoveler, are likely to ingest a wide variety of decaying organic
matter or dead invertebrates that may contain sufficient levels of
toxin to cause botulism. Waterbirds may also be poisoned upon
consumption of zooplankton or wetland invertebrates that have
consumed toxic material. The carcass-maggot cycle, described in
more detail below, is a classic example of secondary poisoning
through consumption of toxin-laden invertebrates, but other
aquatic animals may serve in this role as well. Wetlands are home
to numerous invertebrates and zooplankton that consume organic
debris, particularly in the benthos, and type C botulinum toxin has
been demonstrated in free-living aquatic invertebrates (Kalmbach
& Gunderson 1934, Rocke unpubl. data), crustacea (Rocke
unpubl. data), and zooplankton (Neubauer et al. 1988).
Unfortunately, direct evidence that clarifies the role of inverte-
brates in the initiation of botulism outbreaks is lacking. Instead,
most research has focused on the role of sarcophagous larvae on
carcasses and the carcass-maggot cycle of botulism."

"Carcass-maggot cycle of avian botulism
It is well known that decomposing tissues containing botulinum
spores can support high levels of toxin production (Bell et al.
1955, Reed & Rocke 1992). Fly larvae and other invertebrates are
unaffected by the toxin and, as they feed on decaying matter, they
effectively act to concentrate the toxin. Toxin levels in maggots as
high as 400 000 mouse lethal doses (MLD)/g have been found on
waterfowl carcasses (Duncan & Jensen 1976). With a 50% lethal
dose for type C botulinum toxin in waterfowl estimated at 36 000-
43 000 MLD/kg of body weight (Rocke et al. 2000), ingestion of
only a single toxic maggot could be lethal. Although most water-
fowl will not directly consume a vertebrate carcass, many would
ingest maggots that fall off. In this way, botulism outbreaks in
waterfowl often become self-perpetuating. This has become
known as the carcass-maggot cycle of botulism, and it is thought
that toxic maggots have the greatest potential to cause massive
die-offs of birds (Wobeser 1997)."

ARTICLE

Please don't get me wrong, I'm not trying to be alarmist. It's just that I was totally unaware of this information and it's definitely something I would want to know if I found dead waterfowl by my pond (if I had a pond)(which I don't at this time)(but hopefully will soon)(soon being relative of course).

I have a squirrel that the dogs have killed just waiting for a feeder basket to be installed. neat, neat, neat! I was thinking of a basket floating out in the middle in a inner tube to keep the smell from being to close to shore, then I remembered I have turtles and they surely would figure out a way to get to the carcass. Hey if you felt like you needed to shake up the basket just tie a string to it and give it shake now and then from shore.

I hang my basket from a pole sticking out from the dock. Many times when I'm on the dock I'll give the pole a shake just to see the fish feed. But the maggots will all hit the water on their own eventually. I got a few friends that really look at me funny when they come over fishing and see/smell the "recycling center" as we call it. Just a side note, I hate cats and I've told several neighbors that I'd be glad to recycle theirs for them. They give me a wierd look but little do they know that I'm serious. There are a lot of farrell cats around here and more than one has been converted to fish food. I guess I'm not going to worry about botulism since I only use animals that I've killed myself or I know how they got killed versus died of disease. The only birds I use are my own chickens when they get killed by an animal or something. You know this is a rather morbid discussion isn't it? But that's life I guess.

I use all the walleye scrapes that I catch and basically not much of anything else. I also get donations of other slain walleyes to. Its better than stinking up my garbage can or thiers. My pond is also not located at my residence and i personally dont swim in it. even though its over an acre in size.

DY: For a short time, I thought this might be the answers to everyone's commorant / heron prayers. Looks like it gets the wrong birds though. :-( Bummer!

"Carcass-maggot cycle of avian botulism
It is well known that decomposing tissues containing botulinum spores can support high levels of toxin production (Bell et al.
1955, Reed & Rocke 1992). Fly larvae and other invertebrates are unaffected by the toxin and, as they feed on decaying matter, they effectively act to concentrate the toxin. Toxin levels in maggots as high as 400 000 mouse lethal doses (MLD)/g have been found on waterfowl carcasses (Duncan & Jensen 1976). With a 50% lethal dose for type C botulinum toxin in waterfowl estimated at 36 000-43 000 MLD/kg of body weight (Rocke et al. 2000), ingestion of only a single toxic maggot could be lethal. Although most water-fowl will not directly consume a vertebrate carcass, many would ingest maggots that fall off. In this way, botulism outbreaks in waterfowl often become self-perpetuating. This has become known as the carcass-maggot cycle of botulism, and it is thought that toxic maggots have the greatest potential to cause massive die-offs of birds (Wobeser 1997)."