Originally posted by DJT:
Will a pond with adequate structure have a better carrying capacity than a identical pond with none or is its only purpose to concentrate fish?
That's an excellent question, and one to which I've given a lot of thought.
Carrying capacity is ultimately a measure of available energy--in other words, a pond's ability to gather or receive sunlight, either directly or indirectly. I'd like you to refer to the following post:
When you manage a pond, you're really managing sunbeams. Every fish your pond ever produces, every lily pad that sprouts, every sneaky little screeching frog;.no exceptions. They all came from that carefully managed sunbeam.
In a vacuum, light always travels at a speed of 299,792,458 meters per second. The average distance from the sun to the earth is 150 million kilometers. When light leaves the sun, it takes 8 minutes to speed through space and reach Earth. When the beam of light hits your pond, �let's call him RAY�, it is a packet of energy that will ultimately influence how your pond meets your expectations.
The energy flowing through living organisms starts with sunlight and photosynthesis, then travels through the food chain in bite sized chunks. Primary producers will capture RAY and, through a complicated chemical procedure turn him into usable energy. The animals in your pond called primary consumers, can't do this on their own, so they aren't interested in RAY. They just want to eat who ate him. Secondary consumers eat primary consumers, so RAY moves right on up the chain. Humans can be primary consumers or secondary consumers, but they all rely on RAY as well.
If your pond has suspended silt, RAY hits these little particles, then get sent back out to space. Unless you have a pond on the moon, then this won't help you much. If you have lots of algae, which are primary producers, those near the surface capture and hold RAY, so he can get to you. But if your algae are too thick, some of RAYS friends will get sent to the moon.
A fish is a packet of energy, too. He's a lot bigger packet than a single celled algae, but you can weigh a fish and make a calculation how many sunbeams it took to make him. If you are sending your sunbeams to outer space, then you won't have as many pounds of fish. If you are adding energy into the pond in the form of pellets, you are using RAY'S buddies that landed on someone else's pond or field. Primary producers, like soybeans, may have been a pit stop for RAY. Maybe they landed in the ocean, then became algae, then became a krill, then became a whale, then became a whale poop, then became a bacterium, then became a zooplankter, then became a smelt, then became part of a salmon's spinal chord, then ended in a five gallon pail which got sold to a dude who makes pellets for pond meisters. It still all started with RAY.
Sometimes RAY becomes busy and can't help you. If you love largemouth bass, but the neighbor kid is a bucket biologist who likes to transport brown things with whiskers, then RAY may become occupied for a few years in a bullhead's left eye. If the bullhead dies, then maybe some friendly bacteria will help guide RAY to your biggest largemouth. If you are not lucky, then RAY will go to another bullhead.
Every RAY that's ever successfully met a primary producer in your pond can still be accounted for. If he left the pond, he's somewhere that you could find him. It's fairly easy to guess where he went. He may have been eaten by you. He may have gone through your overflow pipe. He didn't evaporate. He may have left in a kingfisher's body. He's definitely somewhere.
Sometimes RAY enters your pond straight from the sun. Sometimes he hitches a ride on a teeny speck of clay. Maybe RAY had already joined in a great chorus of RAYS in the form of a three inch tilapia. If you could count every RAY in, and subtract every RAY out, that would tell you how many RAYS are left. This number dictates how many pounds of precious fish you have in your pond, be they smallies, bgills, brookies, Tee-Laps, or golden shiners. Every fathead, bigmouth, little redhorse - each and every one owes his existence and thickness to RAY.
RAY is king.
These are examples of a fish community's ability to accumulate energy in the form of fish biomass.
Now, think of the food web, and how the intricate lattice of organisms work their way up the web to your favorite fish. Structure, in the form of let's say, hmmmm, submerged cedar trees, is a substrate for certain key organisms like damselfly larvae. Fish value these sorts of food items, and a properly placed structure may mean that a pond ecosystem is more efficient at moving energy up to your fish. But "efficiency" really isn't your question,is it?
If you look at all of the surface area, of all of your pond's substrate, in the form of aquatic plants, and pond mud, you'd be hard pressed to really add to this by putting in some sunken trees and cars and other similar items. So what I'm really getting at is that your pond, if it has lots of structure may get to your carrying capacity
quicker, or it may rebound from angling pressure
quicker, but it probably doesn't hold more overall biomass, because the sun's net ability to provide energy has changed in only the smallest of ways.
I think structure can be a great thing, but I'd list it's advantages as follows:
1. Concentrates fish for better angling opportunity.
2. Allows your carrying capacity of your pond to better reflect the
kinds of fish that you want by providing ambush points (LMB) or hiding areas (FHM).
3. Allows for some micromanagement of environment in the form of shade.
But I'd contend, that as a broad generalization, that the pond's overall biomass, or
carrying capacity remains unchanged.
I personally minimize structure because I like to seine my ponds on occasion, and the structure can be a pain in the butt.
Let me make it perfectly clear that I'm not discouraging the use of structure. I use it myself. I just personally believe that there's some misconception out there about your pond having tons more fish because you have placed structure.
Welcome, DJT. It's flattering that you've read so many posts, but it's even better that you decided to join the forum.
Bruce