Hartsoe, Inez

Moore, Jewel E.

English

UARK (University of Arkansas )

Journal of the Arkansas Academy of Science Volume 35 Article 27 1981 Crowley's Ridge Biological Station--An Educational Center Jewel E. Moore University of Central Arkansas Inez Hartsoe Follow this and additional works at: https://scholarworks.uark.edu/jaas  Part of the Terrestrial and Aquatic Ecology Commons Recommended Citation Moore, Jewel E. and Hartsoe, Inez (1981) "Crowley's Ridge Biological Station--An Educational Center," Journal of the Arkansas Academy of Science: Vol. 35 , Article 27. Available at: https://scholarworks.uark.edu/jaas/vol35/iss1/27 This article is available for use under the Creative Commons license: Attribution-NoDerivatives 4.0 International (CC BY-ND 4.0). Users are able to read, download, copy, print, distribute, search, link to the full texts of these articles, or use them for any other lawful purpose, without asking prior permission from the publisher or the author. This General Note is brought to you for free and open access by ScholarWorks@UARK. It has been accepted for inclusion in Journal of the Arkansas Academy of Science by an authorized editor of ScholarWorks@UARK. For more information, please contact scholar@uark.edu. Arkansas Academy of Science Proceedings, Vol.XXXV,198188LICHENS OF ARKANSAS II.ADDITIONALSTATE RECORDS THROUGH COMPUTER SEARCHThe lichen herbarium of the American Bryological and Lichenological Society (ABLS)is housed along with the University of Minnesotaherbarium (MIN), at the University of Minnesota. Both collections have been computerized (Wetmore, CM. 1979. Herbarium computerizationat the University of Minnesota. Systematic Botany 4(4):339-350.) and are separated from each other by different data bases. Printouts of the Ar-kansas lichens contained in these herbaria revealed additional records for Arkansas lichens not previously reported (Moore, Jewel E. 1979.Lichens of Arkansas I.A summary of current information. Proc. Ark. Acad. Sci. 33:85-87.): Leptogium sinuatum (Huds.) Mass., Phyxciaconstigata (Nyl.)Norrl. and Nyl., and Caloplaca flavovirescens (Wulf.)Dalla Torre and Sarnth collected by C. Wetmore inFranklin County,Ozark National Forest, CherryBend Campground, 1June 1966;Peltigera malacea (Ach.)Funck collected by Delzie Demaree on West Mountain,Hot Springs National Park, 9March 1954; Cladonia cariosa (Ach,) Spreng. collected by Delzie Demaree at Optimus, Stone County, 20 May I960;andCladonia pyxidata (L.)Hoffm. collected byDelzie Demaree at Daisy, Ouachita National Forest, inPike County, 6 January 1963.These six additions to the lichens ofArkansas bring the state list to 241 species. The systematic synopsis of the lichens of Arkansas, withcommon names (fromNearing, G. G. The Lichen Book.Publ. by the author. Ridgewood, New Jersey) is available from Arkansas Biota (Moore,Jewel E. 1981.Systematic synopsis of the Lichens of Arkansas. Arkansas Biota,publ.by Ark.Acad. Sci.).JEWEL E. MOORE, BiologyDepartment, University ofCentral Arkansas, Conway, Arkansas 72032.CROWLEY'S RIDGE BIOLOGICAL STATION—AN EDUCATIONAL CENTERArkansas may be divided into two principal regions based upon topography, geological substrate, and dominant vegetation—the InteriorHighlands of the northwestern part of the state and the Gulf Coastal Plain of the southeastern part. Within the GulfCoastal Plain is the uniquegeological feature known as Crowley's Ridge (Call, 1891;Foti, 1974). The ridge rises about 250 feet above the flatMississippi AlluvialPlain andextends about 150 miles in length from Helena northward intoMissouri. Crowley's Ridge Biological Station is located on two acres on TitanicRoad, about two miles south of Pollard, in Clay County. There are two buildings which can be used for pioneer-type livingand for laboratorywork.The site is near some of the gravel pits so characteristic of the upper part of the ridge where gravel and sand are obtained forcommercialuses. Surrounding the station are forest stands of oak-hickory-tulip poplar and fields forpasture and wheat production. Deep gullies, frequentlyencountered onthe ridge, and petrified wood of trees from the Eocene Tertiary gravels are found insome of these fields.While the station itself is small, there are ample opportunities for field studies associated with Crowley's Ridge. BigLake National WildlifeRefuge inMississippi County, and the adjacent Arkansas Game and Fish Commission lake yield good habitats forstudying game and waterfowlassociated withsuch cypress lakes. This area is part of the Sunken Lands which resulted from the New Madrid Earthquake of 1811-13. Also inMississippi County are the heronries near Luxora and Burdette from which the state record fornesting glossy ibis was first reported (Hanebrinkand Cochran, 1966). Other nesting species at these heronries include little blue heron, great egret, cattle egret, snowy egret, Louisiana heron, andblack-crowned night heron. Other records fornesting birds and bird migrations are needed to complete the work already begun on these ridgeinhabitants (Hanebrink, 1980). Research on the fishes of Crowley's Ridge has been published (Fulmer and Harp, 1977), but field studies on otheranimals of the ridge are needed.Research on the forest stands ofCrowley's Ridge (Clark et al., 1974; Clark, 1977) indicates that the oak-hickory-pine edaphic climax forestand the white oak-beech stands (present status of the beech-maple climax forest) establish baselines allowing comparison of the extant and extinctforest stands of the ridge. As a rule, the oak-hickory-pine forest follows the irregular outcroppings of the droughty soils inthe northern part of theridge; the white oak-beech stands coincide withthe Pleistocene loess which covers the southern portion of the ridge and disappears on the ridgesummits where the Tertiary sands and gravels produce the soils of the Brandon-Lexington association. The tulip poplar, unique to the Crowley'sRidge area of Arkansas, reproduces inthe cut-over white oak-beech forests. Mud slides also are conducive to this invasion, as wellas to invasionby the cucumber magnolia. The relict stand of two trees of bigleaf magnolia (Moore, 1953; Figler, 1981) is inClay County; as is Chalk BluffNatural Area (Marsh, 1977), which can be used forsampling and describing the forest types of the ridge. The distribution of Arkansas vascularplants (Smith, 1978) indicates a need forbasic inventory-type field work on the ridge and throughout the state.A field studies class from the University of Central Arkansas used Crowley's Ridge Biological Station to make excursions to some of thesehabitats on the ridge. The station is not so large, nor as developed, as the Ouachita Biological Station (Speairs, 1976), but it can be used as a re-search center forindividuals or college classes to study Crowley's Ridge.LITERATURE CITEDCALL,R.E. 1891. The geology of Crowley's Ridge. Vol.II.AnnualReport of the Geological Survey for 1889. Publ. by WoodruffPrintingCo., LittleRock.CLARK,G. T. 1977. Forest communities of Crowley's Ridge. Proc.Ark.Acad. Sci. 31:34-37.CLARK,G. T., J. A. AKERS, S. W. BAILEY,W. H. FREEMAN,M. H.HILL,L.P. LOWMAN,S. O. LOYD, W. R.RANDEL,R.B.ROSEN and J. S. WORKMAN. 1974. Preliminary ecologi-cal study of Crowley's Ridge in Arkansas Natural Area Plan.Ark.Dept. of Planning. LittleRock.FIGLER, R.B. 1981. Alast stand for bigleaf magnolia in Arkansas.Magnolia 17:34-37.FOTI, T.L. 1974. Natural divisions of Arkansas inArkansas NaturalArea Plan. Ark.Dept. ofPlanning. LittleRock.FULMER, R.F. and G. L.HARP. 1977. The fishes of Crowley'sRidge inArkansas. Proc. Ark.Acad. Sci. 31:42-45.HANEBRINK,E. L. 1980. Birds of northeastern Arkansas. Publ. byStuart Rockwell. Jonesboro, Ark.HANEBRINK,E. L. and G. COCHRAN. 1966. An inland nestingrecord for the glossy ibis, Plegadis falcinellus, inArkansas. Auk83:474.MARSH,M. A.1977. Natural area preservation in Arkansas. Proc.Ark.Acad. Sci. 31:116-1 17.88Journal of the Arkansas Academy of Science, Vol. 35 [1981], Art. 27Published by Arkansas Academy of Science, 1981Arkansas Academy of Science Proceedings, Vol.XXXV,1981 89General NotesMOORE, D.M. 1953. Rediscovery ofbigleaf magnolia in Arkansas.Abstract. Proc. Ark.Acad. Sci. 6:9.SPEAIRS, R. K.,JR. 1976. Ouachita biological station. Proc. Ark.Acad. Sci. 30:83.SMITH,E. B. 1978. Atlas and annotated list of the vascular plants ofArkansas. Univ.Ark.Fayetteville.JEWEL E. MOORE, Department ofBiology, University ofCentral Arkansas, Conway, Arkansas 72032, and INEZHARTSOE (retired), PiggottHigh School, Piggott, Arkansas 72454.RATION/DENSITY COMPARISONS WITH CAGED CHANNEL CATFISH*Caged fish culture as a production method for rearing catfish and trout was first started inthe United States in the late 1%0's and has nowbecome more practical than ever for certain situations (Newton, 1980). This is especially true for the utilization of farm ponds whichare suitablefor cages because the fish cannot be easily harvested otherwise. Since 1967, university and governmental researchers have studied and developedcaged catfish culture for the fish farming industry (Lewis, 1969; Schmittou, 1969; Collins, 1971). They first dealt withculture techniques involvingpotentials and adaptations of the method. They used numerous types ofcages and gradually refined studies to include nutritional trials, stockingsizes and rates, genetics, and fish health (Collins, 1978).Research conducted during the 1970's, primarily in Arkansas and Oklahoma, has further refined cage culture methodology and applicationpotentials (Collins, 1971; Collins, 1978; Newton, 1980; Kilambi et al., 1977). These studies are valuable because they demonstrate the variety ofsituations for using cage culture, the improved feed quality for confined fish culture, and the resource potential for both home and commercialventures.Cages are ideal forevaluating rations for fishdiets (Newton and Dean, 1978; Newton et al., 1980). The need continues for testing availablerations forefficient and economical fish production. This study compares two rations ofsimilar protein levels, 33% and 36%, but quite differentin cost withthree stocking densities ofchannel catfish.A total of 18 cages were stocked withcatfish fingerlings during May 1980. Thecages (0.9m1) were arranged inunits of three across the southend of a 1.6 ha farm pond on the University of Arkansas at Pine BluffAgricultural Research Station as described previously by Newton andMerkowsky (1976). Six cages were each stocked with 200, 350, and 500 fingerlings (average wt. 28 g), respectively, in a randomized pattern.Experimental conditions were triplicated simultaneously for ration and density evaluations. Three cages of each fish density were fed either a36% protein trout ration or a 33% protein catfish ration formulated as floating pellets. Allfish were fed fivedays per week at the rate of4% oftheir estimated body weight, regardless ofdensity or ration combinations.The study period began 14 May and ended on 30 August due to an oxygen depletion whichkilled fish in approximately two-thirds of thecages. Nevertheless, all data were collected from each cage similar tousual harvest operations inprevious studies (Newton et al., 1980). Statisticalcomparisons revealed nosignificant differences between data collected from dead or live fish. Therefore, the relative validity of the assumptionsand determinations reported herein are believed tobe accurate forpractical comparisons among density and ration combinations.Evaluations of the rations and stocking densities were based upon weight gain, food conversion efficiency (FCE), survival, and productioncosts per kilogram of catfish produced. Comparisons between rations revealed no significant differences among net production, FCE, andsurvival. Due to the difference in feed costs (the 33% protein ration was $16/45.5 kg, while the 36% protein ration was $25/45.5 kg) the 33%protein ration was the most cost efficient at allstocking densities (Table 1). With either ration, the cost per kilogram of fish produced was less atthe higher stocking densities (350 and 500 fish); however, production costs were still lower for all densities with the 33% protein catfish ration.The greatest net profit per cage was obtained withthe highest fish density forboth rations.There were significant differences in net production among each stocking density, although survival and FCE were similar (Table 2). Fishstocked at 350 per cage had higher average individual gains than fish stocked at 200 or 500 per cage, whichhad similar average gains. Both FCEand survival were consistently within normal ranges necessary for successful caged catfish production. Survival was unusually high, until theoccurrence of the oxygen depletion. One of the disadvantages of cage culture is that caged fish are more susceptible to oxygen problems than fishinan open pond.Since the fish stocked at 350 per cage had higher individual gains with both rations, it appears that this stocking density was optimum forproducing larger size fish. Fish density considerations have been studied forsome time (Schmittou, 1969; Konikoffand Lewis, 1974), and it hasbeen determined that generally a minimum number of 5-6 fish per 30 cm5 isrequired to avoid behavioral problems. We have used 7-8 fish inmostofour studies; however, the maximum or optimum number to stock deserves further attention. Ahigh quality, less expensive catfish ration out-performed a more expensive trout ration on the basis of fishproduction, economy, and availability.This study was supported withfunds provided by USDA,SEA/CR under PL 95-113.89Journal of the Arkansas Academy of Science, Vol. 35 [1981], Art. 27https://scholarworks.uark.edu/jaas/vol35/iss1/27

Crowley\u27s Ridge Biological Station--An Educational Center

ScholarWorks@UARK

Journal of the Arkansas Academy of ScienceVolume 35 Article 271981Crowley's Ridge Biological Station--AnEducational CenterJewel E. MooreUniversity of Central ArkansasInez HartsoeFollow this and additional works at: http://scholarworks.uark.edu/jaasPart of the Terrestrial and Aquatic Ecology CommonsThis article is available for use under the Creative Commons license: Attribution-NoDerivatives 4.0 International (CC BY-ND 4.0). Users are able toread, download, copy, print, distribute, search, link to the full texts of these articles, or use them for any other lawful purpose, without asking priorpermission from the publisher or the author.This General Note is brought to you for free and open access by ScholarWorks@UARK. It has been accepted for inclusion in Journal of the ArkansasAcademy of Science by an authorized editor of ScholarWorks@UARK. For more information, please contact scholar@uark.edu, ccmiddle@uark.edu.Recommended CitationMoore, Jewel E. and Hartsoe, Inez (1981) "Crowley's Ridge Biological Station--An Educational Center," Journal of the ArkansasAcademy of Science: Vol. 35 , Article 27.Available at: http://scholarworks.uark.edu/jaas/vol35/iss1/27Arkansas Academy of Science Proceedings, Vol.XXXV,198188LICHENS OF ARKANSAS II.ADDITIONALSTATE RECORDS THROUGH COMPUTER SEARCHThe lichen herbarium of the American Bryological and Lichenological Society (ABLS)is housed along with the University of Minnesotaherbarium (MIN), at the University of Minnesota. Both collections have been computerized (Wetmore, CM. 1979. Herbarium computerizationat the University of Minnesota. Systematic Botany 4(4):339-350.) and are separated from each other by different data bases. Printouts of the Ar-kansas lichens contained in these herbaria revealed additional records for Arkansas lichens not previously reported (Moore, Jewel E. 1979.Lichens of Arkansas I.A summary of current information. Proc. Ark. Acad. Sci. 33:85-87.): Leptogium sinuatum (Huds.) Mass., Phyxciaconstigata (Nyl.)Norrl. and Nyl., and Caloplaca flavovirescens (Wulf.)Dalla Torre and Sarnth collected by C. Wetmore inFranklin County,Ozark National Forest, CherryBend Campground, 1June 1966;Peltigera malacea (Ach.)Funck collected by Delzie Demaree on West Mountain,Hot Springs National Park, 9March 1954; Cladonia cariosa (Ach,) Spreng. collected by Delzie Demaree at Optimus, Stone County, 20 May I960;andCladonia pyxidata (L.)Hoffm. collected byDelzie Demaree at Daisy, Ouachita National Forest, inPike County, 6 January 1963.These six additions to the lichens ofArkansas bring the state list to 241 species. The systematic synopsis of the lichens of Arkansas, withcommon names (fromNearing, G. G. The Lichen Book.Publ. by the author. Ridgewood, New Jersey) is available from Arkansas Biota (Moore,Jewel E. 1981.Systematic synopsis of the Lichens of Arkansas. Arkansas Biota,publ.by Ark.Acad. Sci.).JEWEL E. MOORE, BiologyDepartment, University ofCentral Arkansas, Conway, Arkansas 72032.CROWLEY'S RIDGE BIOLOGICAL STATION—AN EDUCATIONAL CENTERArkansas may be divided into two principal regions based upon topography, geological substrate, and dominant vegetation—the InteriorHighlands of the northwestern part of the state and the Gulf Coastal Plain of the southeastern part. Within the GulfCoastal Plain is the uniquegeological feature known as Crowley's Ridge (Call, 1891;Foti, 1974). The ridge rises about 250 feet above the flatMississippi AlluvialPlain andextends about 150 miles in length from Helena northward intoMissouri. Crowley's Ridge Biological Station is located on two acres on TitanicRoad, about two miles south of Pollard, in Clay County. There are two buildings which can be used for pioneer-type livingand for laboratorywork.The site is near some of the gravel pits so characteristic of the upper part of the ridge where gravel and sand are obtained forcommercialuses. Surrounding the station are forest stands of oak-hickory-tulip poplar and fields forpasture and wheat production. Deep gullies, frequentlyencountered onthe ridge, and petrified wood of trees from the Eocene Tertiary gravels are found insome of these fields.While the station itself is small, there are ample opportunities for field studies associated with Crowley's Ridge. BigLake National WildlifeRefuge inMississippi County, and the adjacent Arkansas Game and Fish Commission lake yield good habitats forstudying game and waterfowlassociated withsuch cypress lakes. This area is part of the Sunken Lands which resulted from the New Madrid Earthquake of 1811-13. Also inMississippi County are the heronries near Luxora and Burdette from which the state record fornesting glossy ibis was first reported (Hanebrinkand Cochran, 1966). Other nesting species at these heronries include little blue heron, great egret, cattle egret, snowy egret, Louisiana heron, andblack-crowned night heron. Other records fornesting birds and bird migrations are needed to complete the work already begun on these ridgeinhabitants (Hanebrink, 1980). Research on the fishes of Crowley's Ridge has been published (Fulmer and Harp, 1977), but field studies on otheranimals of the ridge are needed.Research on the forest stands ofCrowley's Ridge (Clark et al., 1974; Clark, 1977) indicates that the oak-hickory-pine edaphic climax forestand the white oak-beech stands (present status of the beech-maple climax forest) establish baselines allowing comparison of the extant and extinctforest stands of the ridge. As a rule, the oak-hickory-pine forest follows the irregular outcroppings of the droughty soils inthe northern part of theridge; the white oak-beech stands coincide withthe Pleistocene loess which covers the southern portion of the ridge and disappears on the ridgesummits where the Tertiary sands and gravels produce the soils of the Brandon-Lexington association. The tulip poplar, unique to the Crowley'sRidge area of Arkansas, reproduces inthe cut-over white oak-beech forests. Mud slides also are conducive to this invasion, as wellas to invasionby the cucumber magnolia. The relict stand of two trees of bigleaf magnolia (Moore, 1953; Figler, 1981) is inClay County; as is Chalk BluffNatural Area (Marsh, 1977), which can be used forsampling and describing the forest types of the ridge. The distribution of Arkansas vascularplants (Smith, 1978) indicates a need forbasic inventory-type field work on the ridge and throughout the state.A field studies class from the University of Central Arkansas used Crowley's Ridge Biological Station to make excursions to some of thesehabitats on the ridge. The station is not so large, nor as developed, as the Ouachita Biological Station (Speairs, 1976), but it can be used as a re-search center forindividuals or college classes to study Crowley's Ridge.LITERATURE CITEDCALL,R.E. 1891. The geology of Crowley's Ridge. Vol.II.AnnualReport of the Geological Survey for 1889. Publ. by WoodruffPrintingCo., LittleRock.CLARK,G. T. 1977. Forest communities of Crowley's Ridge. Proc.Ark.Acad. Sci. 31:34-37.CLARK,G. T., J. A. AKERS, S. W. BAILEY,W. H. FREEMAN,M. H.HILL,L.P. LOWMAN,S. O. LOYD, W. R.RANDEL,R.B.ROSEN and J. S. WORKMAN. 1974. Preliminary ecologi-cal study of Crowley's Ridge in Arkansas Natural Area Plan.Ark.Dept. of Planning. LittleRock.FIGLER, R.B. 1981. Alast stand for bigleaf magnolia in Arkansas.Magnolia 17:34-37.FOTI, T.L. 1974. Natural divisions of Arkansas inArkansas NaturalArea Plan. Ark.Dept. ofPlanning. LittleRock.FULMER, R.F. and G. L.HARP. 1977. The fishes of Crowley'sRidge inArkansas. Proc. Ark.Acad. Sci. 31:42-45.HANEBRINK,E. L. 1980. Birds of northeastern Arkansas. Publ. byStuart Rockwell. Jonesboro, Ark.HANEBRINK,E. L. and G. COCHRAN. 1966. An inland nestingrecord for the glossy ibis, Plegadis falcinellus, inArkansas. Auk83:474.MARSH,M. A.1977. Natural area preservation in Arkansas. Proc.Ark.Acad. Sci. 31:116-1 17.88Journal of the Arkansas Academy of Science, Vol. 35 [1981], Art. 27Published by Arkansas Academy of Science, 1981Arkansas Academy of Science Proceedings, Vol.XXXV,1981 89General NotesMOORE, D.M. 1953. Rediscovery ofbigleaf magnolia in Arkansas.Abstract. Proc. Ark.Acad. Sci. 6:9.SPEAIRS, R. K.,JR. 1976. Ouachita biological station. Proc. Ark.Acad. Sci. 30:83.SMITH,E. B. 1978. Atlas and annotated list of the vascular plants ofArkansas. Univ.Ark.Fayetteville.JEWEL E. MOORE, Department ofBiology, University ofCentral Arkansas, Conway, Arkansas 72032, and INEZHARTSOE (retired), PiggottHigh School, Piggott, Arkansas 72454.RATION/DENSITY COMPARISONS WITH CAGED CHANNEL CATFISH*Caged fish culture as a production method for rearing catfish and trout was first started inthe United States in the late 1%0's and has nowbecome more practical than ever for certain situations (Newton, 1980). This is especially true for the utilization of farm ponds whichare suitablefor cages because the fish cannot be easily harvested otherwise. Since 1967, university and governmental researchers have studied and developedcaged catfish culture for the fish farming industry (Lewis, 1969; Schmittou, 1969; Collins, 1971). They first dealt withculture techniques involvingpotentials and adaptations of the method. They used numerous types ofcages and gradually refined studies to include nutritional trials, stockingsizes and rates, genetics, and fish health (Collins, 1978).Research conducted during the 1970's, primarily in Arkansas and Oklahoma, has further refined cage culture methodology and applicationpotentials (Collins, 1971; Collins, 1978; Newton, 1980; Kilambi et al., 1977). These studies are valuable because they demonstrate the variety ofsituations for using cage culture, the improved feed quality for confined fish culture, and the resource potential for both home and commercialventures.Cages are ideal forevaluating rations for fishdiets (Newton and Dean, 1978; Newton et al., 1980). The need continues for testing availablerations forefficient and economical fish production. This study compares two rations ofsimilar protein levels, 33% and 36%, but quite differentin cost withthree stocking densities ofchannel catfish.A total of 18 cages were stocked withcatfish fingerlings during May 1980. Thecages (0.9m1) were arranged inunits of three across the southend of a 1.6 ha farm pond on the University of Arkansas at Pine BluffAgricultural Research Station as described previously by Newton andMerkowsky (1976). Six cages were each stocked with 200, 350, and 500 fingerlings (average wt. 28 g), respectively, in a randomized pattern.Experimental conditions were triplicated simultaneously for ration and density evaluations. Three cages of each fish density were fed either a36% protein trout ration or a 33% protein catfish ration formulated as floating pellets. Allfish were fed fivedays per week at the rate of4% oftheir estimated body weight, regardless ofdensity or ration combinations.The study period began 14 May and ended on 30 August due to an oxygen depletion whichkilled fish in approximately two-thirds of thecages. Nevertheless, all data were collected from each cage similar tousual harvest operations inprevious studies (Newton et al., 1980). Statisticalcomparisons revealed nosignificant differences between data collected from dead or live fish. Therefore, the relative validity of the assumptionsand determinations reported herein are believed tobe accurate forpractical comparisons among density and ration combinations.Evaluations of the rations and stocking densities were based upon weight gain, food conversion efficiency (FCE), survival, and productioncosts per kilogram of catfish produced. Comparisons between rations revealed no significant differences among net production, FCE, andsurvival. Due to the difference in feed costs (the 33% protein ration was $16/45.5 kg, while the 36% protein ration was $25/45.5 kg) the 33%protein ration was the most cost efficient at allstocking densities (Table 1). With either ration, the cost per kilogram of fish produced was less atthe higher stocking densities (350 and 500 fish); however, production costs were still lower for all densities with the 33% protein catfish ration.The greatest net profit per cage was obtained withthe highest fish density forboth rations.There were significant differences in net production among each stocking density, although survival and FCE were similar (Table 2). Fishstocked at 350 per cage had higher average individual gains than fish stocked at 200 or 500 per cage, whichhad similar average gains. Both FCEand survival were consistently within normal ranges necessary for successful caged catfish production. Survival was unusually high, until theoccurrence of the oxygen depletion. One of the disadvantages of cage culture is that caged fish are more susceptible to oxygen problems than fishinan open pond.Since the fish stocked at 350 per cage had higher individual gains with both rations, it appears that this stocking density was optimum forproducing larger size fish. Fish density considerations have been studied forsome time (Schmittou, 1969; Konikoffand Lewis, 1974), and it hasbeen determined that generally a minimum number of 5-6 fish per 30 cm5 isrequired to avoid behavioral problems. We have used 7-8 fish inmostofour studies; however, the maximum or optimum number to stock deserves further attention. Ahigh quality, less expensive catfish ration out-performed a more expensive trout ration on the basis of fishproduction, economy, and availability.This study was supported withfunds provided by USDA,SEA/CR under PL 95-113.89Journal of the Arkansas Academy of Science, Vol. 35 [1981], Art. 27http://scholarworks.uark.edu/jaas/vol35/iss1/27

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Crowley\u27s Ridge Biological Station--An Educational Center

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