Anyone know what causes these spots?

Additional pics here: (Michigan-Sportsman site)

http://www.michigan-sportsman.com/forum/showthread.php?t=256750&highlight=black+spots

Nope, but we see them frequently here to, note the tail on the fish in the pic.

I think its a fungus or parasite caugh this LMB this weekend

Happens to largemouth too. Not sure of the cause! Sun beaten carpet nice fish NOT GOOD!!!

we've had lots of threads about this before. It's some sort of pigmentation alteration.

I e-mailed the pic to the fisheries service for Maryland's DNR ,,,,I will post any info if and when I get it

Its melanoma.

Interesting article I found while surfing on fish melanoma: http://www.news-medical.net/?id=40771

emo bass

emo bass

That's hilarious!

We have caught some in Maine like that too.

They all seem healthy, but are limited to a few lakes.  

Use to come across this black-spot disease on catfish mostly, but also on bass as well.These parasitic flatworms appear as tiny black spots on the skin, fins and flesh of fish. No method of control is available for the elimination of this problem. This organism does little harm to the fish. The main problem associated with black-spot is the unsightly appearance it may cause. Skinning infected fish will remove most black spots.

The life cycle of the parasite is quite complex. A fish-eating bird (typically a great blue heron or kingfisher) eats an infected fish. The black spot or worms are released and grow to sexual maturity in the bird's intestine. The adult worms pass eggs with the bird's droppings. When the eggs reach water, they hatch into free-swimming organisms which then penetrate snails for further development. Finally, after leaving the snails they burrow into the skin of fish and form a cyst. The fish surrounds the cyst with black pigment that gives the disease its name. If an infected fish is consumed by a bird, the cycle repeats itself.

Use to come across this black-spot disease on catfish mostly, but also on bass as well.These parasitic flatworms appear as tiny black spots on the skin, fins and flesh of fish. No method of control is available for the elimination of this problem. This organism does little harm to the fish. The main problem associated with black-spot is the unsightly appearance it may cause. Skinning infected fish will remove most black spots.

The life cycle of the parasite is quite complex. A fish-eating bird (typically a great blue heron or kingfisher) eats an infected fish. The black spot or worms are released and grow to sexual maturity in the bird's intestine. The adult worms pass eggs with the bird's droppings. When the eggs reach water, they hatch into free-swimming organisms which then penetrate snails for further development. Finally, after leaving the snails they burrow into the skin of fish and form a cyst. The fish surrounds the cyst with black pigment that gives the disease its name. If an infected fish is consumed by a bird, the cycle repeats itself.

I've seen the above described spotting in fish before, but mostly in panfish and it has never been as dark or big as the pics being shown in this thread. I have even filet some of said panfish and dissected these little cysts.

Again, I do not think that is the same as the pics being shown in this thread.

emo bass

Is it gonna cry and write a love song and sing it off key?

Use to come across this black-spot disease on catfish mostly, but also on bass as well.These parasitic flatworms appear as tiny black spots on the skin, fins and flesh of fish. No method of control is available for the elimination of this problem. This organism does little harm to the fish. The main problem associated with black-spot is the unsightly appearance it may cause. Skinning infected fish will remove most black spots.

The life cycle of the parasite is quite complex. A fish-eating bird (typically a great blue heron or kingfisher) eats an infected fish. The black spot or worms are released and grow to sexual maturity in the bird's intestine. The adult worms pass eggs with the bird's droppings. When the eggs reach water, they hatch into free-swimming organisms which then penetrate snails for further development. Finally, after leaving the snails they burrow into the skin of fish and form a cyst. The fish surrounds the cyst with black pigment that gives the disease its name. If an infected fish is consumed by a bird, the cycle repeats itself.

I am familiar with Digenetic Trematodes, but those usually manifest as white, pill like cysts beneath the scales in muscle or gill tissue. Neascus (a digenetic trematode) appear as black dots, and is probably similar to what you've seen in catfish. It really is a fascinating life cycle. You are correct in your description of the illness, which rarely is fatal, but in the pictures you see above, is clearly malignant melanoma, and studies have shown that these fish indeed die earlier than anaffected fish from the same region. There has been a ton of recent research about this, and I haven't kept up on it. Perhaps someone currently in the field could add to this.

On a side note, all this talk of critters on the skin has me itchy all over.