ISSN:0002-8487    

DOI:10.1577/00028487.1954.10492357

出版商:Taylor & Francis Group    

年代:1954

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/00028487.1954.10492366

出版商:Taylor & Francis Group    

年代:1954

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/00028487.1954.10492373

出版商:Taylor & Francis Group    

年代:1954

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/00028487.1954.10492374

出版商:Taylor & Francis Group    

年代:1954

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659(1953)83[13:PAPOTU]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1954

数据来源: Taylor

ISSN:0002-8487    

DOI:10.1577/1548-8659(1953)83[20:BSFFSA]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1954

数据来源: Taylor

摘要:

An investigation was made of the food, spawning runs, age and growth, and distribution of the longnose sucker Catostomus catostomus in Yellowstone Lake during the summers of 1951 and 1952. This fish was probably accidentally introduced into Yellowstone Lake by bait fishermen in the early thirties. As many as 2,000 specimens were observed with the annual cutthroat-trout runs in Pelican Creek during the early forties. A total of 1,150 was counted there in 1951. The food of suckers captured in the mouths of tributary streams showed an incidence of 69 percent algae, 40 percent higher aquatic plants, and numerous aquatic insects, particularly Diptera. During the spawning run the largest number of suckers entered the traps on the days when water temperatures were highest. Females were significantly larger than males. The average time spawning fish stayed in Pelican Creek was 19 days for females and 17 days for males. The average loss of weight for spawning females was 4.7 ounces and for males 1.8 ounces. A sample of sucker fry captured on July 9 averaged 13 millimeters in total length. Young taken October 11 averaged 30.5 millimeters. The calculated total lengths for each year of life based on 525 specimens were as follows: first year–2.0 inches; second–4.8; third–8.5; fourth–11.7; fifth–13.6; sixth–15.8; seventh–17.4; eighth–18.1. Females grew more rapidly than the males and reached a larger size. Tagging experiments showed that suckers have a rather restricted range and are frequently taken by pelicans.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1953)83[38:OOTLSI]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1954

数据来源: Taylor

摘要:

Fish populations in large Alabama rivers and large impoundments were sampled by using emulsifiable rotenone at a concentration of 1 p.p.m. which is applied to measured areas with pumps and hose. Large channel, blue, and flathead catfishes appeared to be the principal piscivorous species in rivers. The ratios of the weight of forage fish to piscivorous fish and the percentages by weight of harvestable fish in the entire populations appeared similar to those in pond fish populations. The change of environment following impoundment of rivers caused large changes in the species composition of the stock. Pollution of rivers produced changes from balanced to unbalanced fish populations. In one river a polluted area had a smaller standing crop than did an unpolluted portion of the same river, while in another, the polluted area had the larger stock.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1953)83[47:FPIARA]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1954

数据来源: Taylor

摘要:

McFarland Pond was constructed in 1946 and stocked with 23 2-year-old bluegills (Lepomis macrochirus) in 1947. Scales from the 1947 to 1949 year classes of bluegills were studied with particular attention to the recognition of false and true annuli. No consistent changes in coefficient of condition, K, were noted except for a tendency for the K value to increase with increase in length of fish. Annulus formation occurred from mid-February to mid-June, with most fish forming annuli in the last half of May or early June. Although the body-scale relationship is better described by a third-degree equation, calculated lengths based upon a straight-line relationship were nearly as accurate. The brood stock grew rapidly when first placed in the lake. The 1947 year class grew less in 1947 than did the 1948 and 1949 young of the year during their first summers. Late spawning was probably the cause of the poor growth in 1947. By 1949, the bluegills were severely stunted and showed little growth after they reached 1 year of age. Most of the season's growth was completed by early July. The faster growing individuals disappeared before their third year. Male bluegills showed more rapid growth than females after the first year of life. About 90 percent of the 1948 and 1949 year class bluegills showed checks on their scales before the first annulus whereas only 10 percent of the 1947 year class bluegills showed such false marks. False marks after the first annulus seem to be connected with sexual activity. Suggestions are given for recognizing false annuli.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1953)83[58:GOBIAN]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1954

数据来源: Taylor

摘要:

Stomach contents were analyzed for 420 specimens of wild brook trout (Salvelinus fontinalis) from the Pigeon River, Otsego County, Michigan. All fish were caught by anglers and checked by trained personnel from April 26 to September 14, 1952. Data on coefficient of condition and volume of stomach contents were averaged by 2-week periods. Both condition and volume of stomach contents were highest in May and June and decreased thereafter during the angling season. The data suggested a close relationship among periodicity of growth, condition, and mean volume of stomach contents.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1953)83[76:SFITFO]2.0.CO;2

出版商:Taylor & Francis Group    

年代:1954

数据来源: Taylor