Smallie Attack!

[Jim J]

[Gary L]

Is it my imagination or does that Crawfish have a frightened look on his little face.

[jim bielecki]

 

 

Awsome Pic!!!

[Rick D.]

Is that fear of being dinner on that crawfish's face?

or

Is that pleasure from that smallie kissing it on the bootie?

 

GREAT PIC!!!

[Guest Don R]

Too funny Gary. I was thinking the same thing.

[Tim Smith]

I'd like to know the back story...

 

...does the smallie catch this crayfish?

 

I'd give even odds. This pass looks like a likely miss. The smallie has a closed mouth and the crayfish is in cover and looks to be rotating fast to get it's claws in position to fight. That's a pretty big crayfish for that size of smallmouth too...can't see enough to be sure, but from the size and the black bands on the claws it looks like it might be a rusty crayfish too...very nasty species.

 

Who wins this battle, Jim?

[Tim Smith]

...I was curious enough to e-mail the photographer and here is his reply.

 

Hi Timothy,

 

Thanks for your kind words and interest in my fish pictures.

As I recall, the smallmouth in the picture did in fact briefly pick up that rusty crayfish. But he dropped it almost immediately, and swam away.

After years of viewing the interaction between crayfish and smallmouth bass, I've come to learn that they will not eat adult crayfish during the hard shell period. As you may know, crayfish go through a molting process periodically when they shed their exoskeleton or outside shell. After this process, the new shell is soft, but gradually hardens. When the shell is in the hard condition, smallmouth avoid eating them. I'm not sure why. They absolutely love them however, when they're in the soft shell phase.

Also, although I can't tell the difference with my eyes, the bass can almost always determine if the shell is hard or soft. I cannot determine weather they do this by sight or by smell. I've seen evidence that would support the notion that both senses are capable of this detection.

It's all pretty interesting.

Anyway, a long answer to your question.

 

I will go to your website and check it out.

 

Thanks again for your email. Nice hearing from you.

 

Eric Engbretson

Engbretson Underwater Photo

[Guest rich mc]

i have often heard the lake michigan perch guys talk of using soft shells> is this a phase that happens around the full moon too. how often do they change their hard cover?

[Tim Smith]

i have often heard the lake michigan perch guys talk of using soft shells> is this a phase that happens around the full moon too. how often do they change their hard cover?

 

Soft shells happen after a crayfish "molts" or sheds its outer shell. After a molt they are soft and rubbery (you can even bend their claws and legs like rubber). During that time they are easily eaten by predators of all sorts including each other.

 

I'm not aware of any connection to phases of the moon, but I suppose it's possible. The thing that definitely drives crayfish molts is growth. Very young crayfish molt every few weeks until their growth levels off. Adult crayfish tend to molt once in late May or June. Some species may molt more often than that, but most grow slowly in the later stages of their lives.

[jamie shard]

is this a phase that happens around the full moon too.

 

I'm not sure if molting is synchonized, but I think they typically spawn during a full moon -- could be a myth.

 

-j

[jude]

Cool pic. The response from the photographer was very enlightening. Do the crayfish within a certain area all molt at the same general time, or is it staggered. I guess I'm wondering if it's like a mayfly hatch. If so, it would be wise to turn over a few rocks upon arriving at your river. Catch a crayfish. If it's soft, the hatch is on!

[Tim Smith]

Hey Jude...You'll find clusters of molts in late spring that lead me to believe the molts are often done close together in time. I don't think it's quite as tight as a mayfly hatch, but there would be advantages for the crayfish if it were. Spring is a big growth time when forage is abundant and temperatures are ideal.

 

Jamie, it has been my experience that crayfish spawn whenever and wherever they can. I've collected them in buckets from the bottom of drained ponds during the fall and summer and sometimes they'll be locked up together then (I have a picture of that some where, but this is a family forum after all). Maybe there's MORE spawning during the full moon? I've never heard anything along those lines. Where did you hear that?

[Tim Smith]

 

 

Mr. Engbretson kindly forwarded some additional pictures of smallmouth bass consuming crayfish.

 

The crayfish species on the bottom left is a common one in Illinois, the Northern crayfish (Orconectes virilis). I think the one being caught off a log is a rusty. I'm not sure about the one in the upper left...probably a rusty too.

 

Definitely check out Eric's site. Very, very cool pictures all 'round. I get the impression Eric is doing this as a business, so if you use the pics, be sure to pay.

[Jim Kast]

I have always heard that a Smallie will take a crayfish into it's mouth and clamp down. If the shell is hard it'll spit it back out. Whenever fishing with a Yum Crawbug, I always feel the initial "hit", then wait for the 2nd or 3rd tap to set the hook. I've always attributed the first hit as the "test run". Crawbugs seem to work pretty well year round, so who knows what's what with the whole molting issue?

[Tim Smith]

Crawbugs seem to work pretty well year round, so who knows what's what with the whole molting issue?

 

It all depends on growth.

 

If an exoskeleton is getting tight, a crayfish will molt. Most of that happens in the spring. A few of the older stragglers give it a whirl later in the year. In their first year of life, when growth is rapid, crayfish are molting constantly.

I've also pulled plenty of hardshelled crayfish out of bass guts (non-destructive diet analysis after electrofishing surveys) but they're generally smaller proportional to the bass than the ones pictured here. I believe your "testing" hypothesis, but I suspect that's more true for larger crayfish than smaller ones.

[Jim J]

In their first year of life, when growth is rapid, crayfish are molting constantly.

 

 

Seems I've read about studies showing preferred crawfish size which is generally small (2-2.5 inches)

 

Would this be because smaller craws are younger craws and molting more?

[Tim Smith]

Seems I've read about studies showing preferred crawfish size which is generally small (2-2.5 inches)

 

Would this be because smaller craws are younger craws and molting more?

 

They are molting more often, yes, but the smaller ones also put up less of a fight and have less effective claws for fighting.

 

Bass do eat hardshells, just not as readily.

[jamie shard]

Maybe there's MORE spawning during the full moon? I've never heard anything along those lines. Where did you hear that?

 

I came across that factoid when I was researching colors for crayfish lures about a year ago. The reason I figure it might be a myth is that I only see it quoted on fishing sites! It might be that guys are out fishing during the bright nights and crayfish lures work... so they created a premise to fit the facts. I haven't found a journal article that says the same thing-- yet.

 

So, Believe it... or Not!

 

I'm still trying to get a handle on crayfish colors. Here's where my research left off:

 

 

northern, Orconectes virilis:

green to red brown body

orange tip pincers with whitish knobs (can use white flash)

up to 5"

papershell, Orconectes immunis:

pale grey green body (pale area down middle of top), males purple hued

orange tip pincers,

2-3.5"

also Blandingii actus, lakes, ponds, sloughs

dark red with darker stripe down back,

slender pinchers

propinquis, riffles in streams rarely bigger than 2.5"

dark and blue

 

That's as far as I got. Seems to explain why olive and orange works... and maybe blue and black and maybe purple and black. Sometimes I can't tell if I like fishing because of the biology or biology because of the fishing!

 

-j

[Tim Smith]

The moon issue is still interesting. It seems to me there are quite a few researchers who have made their names by formally studying "myths". The progress from myth, to data to printed page is still a slow one in ecology. Something like that might have been studied and then turned down by the journal reviewers...who's logical processes can be inscrutible at times.

 

I think by Blandingii acutus you mean Procambarus acutus. Here's a picture of those. They like siltier bottoms and are more common in lakes. They're very similar to, and often live together with Procambarus clarkii, the aquacultural species that supports the cajun food industry down there.

 

 

 

Most of these are O. virilis. The one with the blue chela in the middle is an O. virilis. The one with the greenish mottled chela just below it is O. immunis. The colors for all these species becomes more pronounced when they have high protein diets.

 

 

[jamie shard]

Is it wrong that I get hungry when I look at those piles of crayfish?

 

[Tim Smith]

Is it wrong that I get hungry when I look at those piles of crayfish?

 

 

I sure hope not, jamie...there's a reason they're in piles, and it wasn't so I could photograh them.

[jbcook]

Cool thread. I found it interesting to see those smallies eating craws so huge relative to their own size. It's got me thinking about upsizing.

[Tim Smith]

Cool thread. I found it interesting to see those smallies eating craws so huge relative to their own size. It's got me thinking about upsizing.

 

Based on what you find in their stomachs, the ratio of the crayfish cephalothorax length (head and abdomen) to bass total length should be under 10%. Anything bigger than that in a bass' gut is likely to be a softshell.

[skjordan]

Based on what you find in their stomachs, the ratio of the crayfish cephalothorax length (head and abdomen) to bass total length should be under 10%. Anything bigger than that in a bass' gut is likely to be a softshell.

 

Now thats a peice of trivia that you wont be getting on any other forum.

 

This will give fly tiers some insight as to how big we should be tying our craw imitations.

 

Is there a similar ratio for bait fish.

[Tim Smith]

Now thats a peice of trivia that you wont be getting on any other forum.

 

This will give fly tiers some insight as to how big we should be tying our craw imitations.

 

Is there a similar ratio for bait fish.

 

 

I know some for largemouth.

 

33% max length gizzard shad to body length

 

24% bluegill

 

40% small largemouth (prey)