Pond Boss Forums POND CONSTRUCTION Creating habitat structure and carrying capacity

Anyhow here is my question. Will a pond with adequate structure have a "better" [emphasis added] carrying capacity than an identical pond with none or is its only purpose to concentrate fish?

DJT did not ask if it created "bigger" or more carrying capacity.

In a word yes on the first part of the question and no on the second. I may well disagree with some on this point.

The only reason for cover is not to just concentrate fish !!

In many reservoirs as they age woody cover etc is missing through deterioration and those waters become less productive of what the manager/public want. That is fish in a balanced proportion. They may produce other stuff that fills up carrying capacity.

Not to get tangled in definitions. Carrying capacity (amount of productive ability) is a very dynamic and complex concept. It changes based on many things and is not stagnant. In some situations carrying capacity can be tripled by fertilization and quadrupled by adding supplemental feeding. Trophic ability of the water varies greatly and often changes over time. Carrying capacity (except in how that capacity is divided) is usually not a problem in ponds except in those that are managed like an aquaculture operation. Water quality can be a problem unrelated to the degree of carrying capacity in use.

Structure is the contour components of the pond bottom ( rock piles , ditches , humps , points , flats etc) while cover has to do with material which deteriorates over time (usually added by man or nature) like trees , brush , plants or others. So the two overlap and thus cover /structure is used interchangeably by many when used in the context of things we add to a pond. If one adds large rocks to make a pile it is structure and if one adds brush piles it is cover , but both are added enhancements.

http://www.pondboss.com/cgi-bin/ubbcgi/ultimatebb.cgi?ubb=get_topic;f=4;t=000114;p=1


Crowder and Cooper (1979) developed a
conceptual model which predicts that fish will

maximize their feeding efficiency and growth at

some intermediate level of structural complexity.

Prey availability and vulnerability as related to

structural complexity are important components

of this model. For example, many types of prey

are less vulnerable in dense structure and have low

abundance in structureless areas. Thus, structural

complexity can influence the feeding and refuge

influence of structure. Glass's (1971) results support

this model in that increased structural complexity

reduced both attack and capture rates of

largemouth bass. Savino and Stein (1982) found

similar results in their study. Helfman (1979,

198la) found that shade-producing objects attracted

bluegilis, and he suggested that prey may

use shade to gain protection from predators.


"Variable Effects of Habitat Enhancement Structures across Species and Habitats in Michigan Reservoirs"

Fisheries managers have long recognized the potential

of habitat enhancement structures to attract

and hold fish (Brown 1986). The first state management

agency to document the use of habitat

enhancement structures was the Michigan Conservation

Department, which added brush shelters

and gravel piles to lakes in the early 1930s (Hazzard

1937). Since that time, numerous state and

federal agencies and local organizations have undertaken

habitat enhancement projects in both

freshwater and marine systems using a variety of

materials (Tugend et al. 2002).

Habitat enhancement structures are added to aquatic systems when natural habitat is perceived to be lacking or insufficient (Prince et al. 1977), with the goal of providing additional cover and concentrating fish and so increasing some combination of recruitment, survival, growth, and angler catch rates (Johnson and Stein 1979).

Habitat enhancement structures can produce

these positive effects through a variety of mechanisms.

For example, habitat enhancement structures

have been proposed to increase recruitment

by providing cover for spawning (Vogele and

Rainwater 1975; Hoff 1991; Hunt et al. 2002),

thereby increasing nest density. Nest success may

also increase if structures provide habitat that allows

adults to more effectively protect their young

(Hoff 1991). Structures can also offer refuge from

predation and alter survival by increasing cover

(Bohnsack and Sutherland 1985; Johnson et al.

1988; Moring and Nicholson 1994), providing

shade (Helfman 1979, 1981; Johnson and Lynch

1992), and providing sites for orientation and

schooling (Klima and Wickham 1971; Bohnsack

and Sutherland 1985). Accordingly, prey abundance

in the vicinity of structures may be enhanced

(Wege and Anderson 1979; Aadland 1982; Moring

et al. 1989), in turn increasing the abundance, feeding

efficiency, and growth of predators (Wege and

Anderson 1979; Bohnsack 1989). Habitat enhancement

structures, particularly in the form of

artificial reefs, also have been proposed to increase

public access by making it easier for anglers to

locate fish and to increase angler catch rates by

concentrating fish (Bohnsack 1989).


I submit that the things noted above result in a pond with better and a more utilized carrying capacity for the things most pond owners want , a balanced growing fishery.