Pond Boss Magazine
https://www.pondboss.com/images/userfiles/image/20130301193901_6_150by50orangewhyshouldsubscribejpeg.jpg
Advertisment
Newest Members
SueSanderson, hawkeye05, CW0808, Razorback, TinD
17188 Registered Users
Forum Statistics
Forums36
Topics38,775
Posts526,961
Members17,189
Most Online3,583
Jan 15th, 2020
Top Posters
esshup 25,260
ewest 20,560
Cecil Baird1 20,043
Bill Cody 13,727
Who's Online Now
18 members (Quarter Acre, tyler0421, Kris B, Lyn, CityDad, anthropic, roymunson, Fyfer123, Theo Gallus, catscratch, RStringer, Rick O, Drago, Bobbss, DannyMac, DrLuke, klingj8, Bruce Bruce), 349 guests, and 457 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
2 questions for Mr Cody.
#533764 04/11/21 09:00 AM
Joined: Jul 2016
Posts: 263
Likes: 8
A
azteca Offline OP
OP Offline
A
Joined: Jul 2016
Posts: 263
Likes: 8
Hello.

Is it possible that the perch eggs that we see floating on the water, are mostly unfertilized eggs.

I think there is a controversy concerning Copepodes (Cyclops), especially among aquarium owners to the effect that Cyclops can be predatory of very small larvae of fish.
What do you think.
A+

Re: 2 questions for Mr Cody.
azteca #533786 04/11/21 05:22 PM
Joined: Apr 2002
Posts: 13,727
Likes: 47
B
Moderator
Ambassador
Field Correspondent
Lunker
Offline
Moderator
Ambassador
Field Correspondent
Lunker
B
Joined: Apr 2002
Posts: 13,727
Likes: 47
Floating perch eggs. I think ribbons of perch eggs have a tendency to float when they are dipped out of the water and get air mixed within or into the ribbon. The ribbons are hollow. Air in the ribbon tends to make the ribbon more likely to float. Rising gases produced within the pond could also get trapped in the ribbon and cause it to float. I am not sure that unfertilized and dead, dying eggs would produce enough gas to float a ribbon - maybe? Best way to check for unfertilized eggs is the individual eggs will turn opaque, noticeably white a few days after it is laid when eggs are dead-unfertilized.

"...controversy concerning Copepodes (Cyclops), especially among aquarium owners to the effect that Cyclops can be predatory of very small larvae of fish". Some of the large common pond Copepods are considered predatory but IMO the predation actually best described as food selectivity in freshwater and marine studies has typically been on items a lot smaller than a fish fry; things mostly such as small forms of algae and maybe tiny protozoa. (See below).

Most common pond dwelling Copepods mainly Cyclops and Mesocyclops are generally small in the size length range of 0.9-1.3mm. Yellow perch eggs range in diameter of 2 to 4.5 mm depending on the amount or degree of egg water hardening. Body length of newly hatched YP fry ranges from 5.5 to 6.5mm. I doubt that the common pond Cyclops species could ever attack and eat something 4 times larger than themselves. Swim up perch fry could easily swim much faster than swimming adult Copepods so IMO the chances of common pond Copepods eating YP fry is not possible. Yellow perch fry commonly feed on the nauplii (baby Copepods) and rotifers. Perch fry after several days eat lots of adult Copepods. I think adult Copepods are much more likely to eat newly hatched 'baby' Copepods(nauplii 0.22-0.25mm) than yellow perch fry. Although I think nauplii are likely still too big for adult Copepods to eat. Tiny algae cells range in size from 2um to 20um(0.002-0.02mm).

Not a lot of research has been done about the feeding habits of small, tiny Copepods who have shown some ability to exhibit feeding selectivity. Research has shown that this selectivity is primarily based on eating algae with factors such as size, motility and taxonomic composition are considered the major items controlling the feeding selectivity of copepods. It is generally assumed that small copepods, including nauplii, feed primarily upon small-sized phytoplankton and including even organic detritus pieces. This is general info from Wikipedia – “Most free-living copepods feed directly on phytoplankton, catching cells individually. " (Note- "Catching cells individually" is probably how the term predation by Copepoda originated.) "A single copepod can consume up to 373,000 phytoplankton per day.[12] They generally have to clear (or search) the equivalent to about a million times their own body volume of water every day to cover their nutritional needs.[13] Some of the larger Copepod species are predators of their smaller relatives.”

Last edited by Bill Cody; 04/11/21 05:36 PM.

Keep This Forum Viable, Read Pond Boss Magazine -
America's Journal of Pond Management
Re: 2 questions for Mr Cody.
azteca #533799 04/12/21 06:03 AM
Joined: May 2004
Posts: 12,953
Likes: 42
Moderator
Lunker
Online Confused
Moderator
Lunker
Joined: May 2004
Posts: 12,953
Likes: 42
Right there is more than I knew I needed to know about Copepods. Thanks, Bill.


"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
[Linked Image from i582.photobucket.com]
Re: 2 questions for Mr Cody.
azteca #533806 04/12/21 10:35 AM
Joined: Jul 2016
Posts: 263
Likes: 8
A
azteca Offline OP
OP Offline
A
Joined: Jul 2016
Posts: 263
Likes: 8
Hello.

Thank you Mr. Cody.
I was wondering because there are a lot of Cyclops in the pond this spring.

A+


Link Copied to Clipboard
Today's Birthdays
57jeepster, Augie, mbunimog
Recent Posts
Containing Fish in a Pen
by Fyfer123 - 05/07/21 09:48 AM
Augie's Another Year Closer to Pond Perfection!
by RStringer - 05/07/21 09:37 AM
Another winter kill
by DrLuke - 05/07/21 08:50 AM
Another Havasu Giant RES
by Sunil - 05/07/21 07:01 AM
Optimal Junior feed
by NEDOC - 05/07/21 06:59 AM
New property, old pond. What to do?
by SueSanderson - 05/07/21 04:48 AM
Minnows not feeding in Forage pond?
by Kyscentlok - 05/07/21 12:25 AM
Guessing why Fla & N LMB aren't the same
by anthropic - 05/07/21 12:24 AM
Metal to Metal
by Heppy - 05/07/21 12:07 AM
Trouble catching bluegill
by Heppy - 05/06/21 11:56 PM
What did you do at your pond today?
by anthropic - 05/06/21 11:45 PM
Newly Uploaded Images
Establishing new Maine pond.
Establishing new Maine pond.
by Mainahs70, April 5
Mongo's New Pond
Mongo's New Pond
by Mongos Pond, February 27
Ice Ice Baby
Ice Ice Baby
by highflyer, February 21
ID?
ID?
by Quixotic, February 7
pond gone
pond gone
by Stressless, January 31

� 2014 POND BOSS INC. all rights reserved USA and Worldwide

Powered by UBB.threads™ PHP Forum Software 7.7.4