Culture Journal: Parvocalanus crassirostris

[Ummfish]

Proof that being a breeder is all about the heart and the care and not about money and power.... see what I get... a nap....

Damn. I was holding out for the money and power. I'm so bummed: Not a single person has tried to bribe me yet. I guess I'll have to go back to the fallback: Breeding fish is a great way to attract dates with people with questionable moral character. I hope so, at least.

Some very interesting info there!1 Let me know when you decide to split your cultures, i'd be more than happy to buy a starter culture from you!

We'll see if I can grow them. The jury's still out on that. If you want to get started in the meantime, Algagen seems like a pretty good company and the starters aren't unreasonable. I'm pretty impressed with how quickly the starter showed up and how well everything was put together.

 

[Ummfish]

I have a picture of an adult for you guys. Don't get too excited. I took it with my phone:

 

[hurrafreak]

lol, that's awesome!!

 

[Zooid]

Wow...that's bigger than I expected hehe.

 

[Cake_Boss]

You sure it's not the other speck?

Sent from my DROIDX using Tapatalk

 

[Ummfish]

Yeah, the adults are almost a millimeter. I'm sure it's not the other speck. This one was jumping around. Like they do.

 

[Whys Alives]

Males do not feed, though they possess rudimentary, non-functional mouthparts.

Just like guys and nipples.

The reasons these copepods are so important is because all life stages are pelagic (so the fish can choose different prey of good size when it's the right time for them)...

How does all of the copepod's life stages being pelagic make it important and how does that affect prey size options for the fish? Also, pelagic is to the water column as benthic is to the sand bed?

Proof that being a breeder is all about the heart and the care and not about money and power....

Creation is power. The currency is joy.

 

[thejrc]

How does all of the copepod's life stages being pelagic make it important and how does that affect prey size options for the fish? Also, pelagic is to the water column as benthic is to the sand bed?

Many many reasons, and yes pelagic is water column benthic means substrate (not necessarily sand bed, just surfaces).

Feeding in larval fish can be broken down to four basic characteristic needs:

1. Prey size - food must fit in mouth (various life stages of copepod nauplii mean various food sizes)

2. Encounter rate - how much food is available, will the larval fish encounter enough for substenance without over-exerting energy

3. Prey movement - Does the food source move in such a way as to stimulate feeding?

4. Nutritional content - The biggest downfal of traditional larval feeding methods as we currently use rotifers and baby brine shrimp both of which lack fundamental nutritional content. Thus we gut load and enrich the critters using them as more of a delivery mechanism rather than a food source persay

Having thrown all that out there many of the reasons pelagic copepods are being examined as a food source is that varying species posess all four of these qualities! It is important to think of copepoda as a large group containing several (several times several in fact) species with varying attributes. Hobbyists are familiar with the T. californicus species (Tigger pods) which is quite large and benthic but often fail to recognize that there are many other species out there with better attributes for larval fish. That is not to discount T. cali as a food source as it really is a very valuable species; it just does not posess the size and encounter specific needs of many larval fish. A larval fish swimming in the water column is not very likely to encounter a T. cali naup resting on the glass.

 

[Whys Alives]

Makes sense now. Thanks.

Any application to invert breeding?

 

[thejrc]

short answer to that one is yes, though off hand I cant kick out any immediate examples. Coincedentally invert larvae itself is another possible food source for fish larvae. Consider size, nutritional content and such of various crab larvae and snail veligers might be the ticket as well!! Matthew Wittenrich was experimenting with snail veligers at one point.

 

[Whys Alives]

Stage (W, L)
Egg (58, )
N1 (39, )
N2 (47, 73)
N3 (53, 106)
Adult female (162, 403)

Naups reach N3 in just less than one day (and begin feeding). Copepods reach adulthood in 6 days.

Just for clarity, this is width and length in microns?

 

[Cake_Boss]

Why Alives are you interested in breeding?

 

[Whys Alives]

Why Alives are you interested in breeding?

That's what she said.

I'm putting together a kreisel and breeder right now. I'm starting with Sexy-Shrimp, then I'll explore Blue Velvet Nudibranch.

You can find my thread here, here, and here.

 

[KhensuRa]

Having a ton of sexy shrimp would be cool...

 

[Cake_Boss]

Very sweet. Welcome to MASC

 

[Ummfish]

How does all of the copepod's life stages being pelagic make it important and how does that affect prey size options for the fish?

Larval fish have really sucky vision and spend all their time in the water column. But they are also really picky about the size of the food that they eat. So, when they are swimming around up there right next to the surface they need to have food come to them that's also the right size so they want to eat it. Even beyond that, food that's a good size one day might be too small the next day as the larvae grow (if food is too small, it won't give the larva enough energy to offset the energy costs of chasing it down and eating it). And not all the larvae will grow at the same rate. Because all the life stages of these copepods are pelagic--and there are like ten stages from egg to adult--every stage is available as an option to the larvae for food choices.

Any application to invert breeding?

Depends on the invert. Some inverts don't eat at all before they change to their benthic form. Some just eat phytoplankton before they change. Some would definitely benefit, like larval shrimp. "Invert" is a great big category of a lot of very diverse critters.

 

[Ummfish]

Sorry. I missed a whole bunch of posts. Yes, the measurements are in microns.

 

[Whys Alives]

Thanks for the welcome everyone.


Okay, I think I get it now. I didn't realize the pods we are used to seeing aren't naturally palegic. I take it the the life stage sizes are more limited for the traditional pods? Some comparisons might be helpful to readers.

You say shrimp, but I assume you don't mean sexy-shrimp.

So how hard are these guys to keep?

 

[Ummfish]

Umm, well tigger pods are big. I don't have a table of their life stages, but adults are 1-3 mm (1000-3000 microns vs. 403 microns quoted above for Parvocalanus). No stages of tigger pods are pelagic, though I've seen them use water tension as a benthic surface. Whatever, none are really available to larvae.

By shrimp, yeah, I'd bet sexy shrimp would eat them. I don't think you need copepods to rear sexy shrimp, but I'd bet you'd get better survival if they had them.

 

[Whys Alives]

I'm going to start with baby brine shrimp, but I might want to try these pods instead at some point. I can somewhat understand your excitement as these pods pose keystone potential. Not a tool I specifically need right now, but almost certainly a path in the right direction.