摘要:

Sport fishing for striped marlin (Tetrapturus audax) began off southern California in 1903. Catches of this species have fluctuated widely. Some of the annual variation in catch (15% to 25%) may be attributable to variations in water temperatures. When the marlin season ends in southern California, usually in November, some fishermen who own yachts begin fishing for billfish in Mexican waters, particularly near Cabo San Lucas and La Paz, Baja California. This fishing is restricted to winter and spring because of severe tropical storms which occur in the summer, and lack of protective harbors except at La Paz.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1975)104<1:FFPBOS>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

From 1960 to 1965, 12,151 winter flounder (Pseudopleuronectes americanus) were tagged with Petersen tags at 21 locations off Massachusetts. Returns through 1971 totaled 4,440 or 36.5%. Ratio of females to males at tagging was 2.3. Movements north of Cape Cod were relatively localized and confined to inshore waters, whereas south of Cape Cod, flounder seasonally dispersed in a southeastward direction generally beyond the territorial limit; movements appeared to be related to water temperature. Little mixing occurred between Georges Bank and inshore areas. Growth of fish north of Cape Cod, south and east of Cape Cod, and on Georges Bank was described by “Walford lines” developed from tagging data. In 1964 apparent rates of exploitation, natural mortality, and annual total mortality were 0.201, 0.273, and 0.474, respectively, for fish released in Vineyard and Nantucket Sounds.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1975)104<13:WFMGAM>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

Summer nighttime abundance and localized distribution of fishes in a tidal cove were studied by beach seining for comparison with a previous daytime study. American eels were relatively abundant at night and absent during the day. Alewife, blueback herring, and Atlantic silver-side were more abundant in the cove at night. Although mummichog numbers were greatly reduced at night, they remained an important constituent of the night fauna. Lesser components of the night fauna included Atlantic herring, Atlantic tomcod, smooth flounder, winter flounder, and rainbow smelt.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1975)104<30:NCOFIA>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

Food habits of 568 juvenile red drum, Sciaenops ocellata (Linnaeus), ranging from 8.0 to 183.0 mm standard length, were determined during the time the fish utilized a Louisiana salt marsh as a nursery area. Potentially available food organisms were sampled during the 7-mo study. Some degree of selectivity by juvenile red drum was demonstrated, but generally the most abundant organisms of an edible size were utilized most heavily. Changes in food with increasing size can be described in three phases: 1) red drum less than 15 mm ate zooplankton; 2) between 15 mm and 75 mm the red drum ate mostly small bottom invertebrates and the young of other fish; 3) red drum larger than 75 mm ate decapods (crabs and shrimp) and fish. Some differences between day and night feeding were found. For red drum 65 to 85 mm the dominant food eaten was grass shrimp during the day, whereas at night it was fish. The length-weight relationship was log W = −7.2052 + (4.1913) (log L). The average coefficient of condition was 1.969. Average growth per month ranged between 13.8 and 25.6 mm during the study period.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1975)104<35:FHLRCF>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

A 4 m2stationary drop-net capable of sampling the entire column of water in depths up to 1 m is described. The net is a modified purse seine constructed of 3-mm nylon mesh with top enclosed and hung from a frame 1 m above the surface. The net is dropped when support pins are released via a trip line from the shore. In 25 paired trials, the haul seine, with its greater area of coverage per haul (525 m2), captured more species than the drop-net, but the drop-net yielded estimates of a significantly higher density for fish and macrocrustaceans by individual species.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1975)104<46:DOASDF>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

A comparison was made between density estimates of estuarine benthos based on artificial substrate sampling and direct observation by divers. Differences suggest that artificial substrates may preferentially sample certain portions of the fauna, leading to erroneous estimates of population size.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1975)104<50:TUOASI>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

Survival of anchovies (Stolephorus purpureus), held in tanks for 30 days after being tagged with a tiny wire implanted automatically by a new device, was 80.5% and tag loss 14.7%. Both criteria were superior to those reported for engraulids tagged by other methods. Advantages of the new tag are small size, internal location, ease of implantation, and capability of being detected automatically.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1975)104<53:ASMFTT>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

Ultrasonic transmitters were surgically implanted into the peritoneal cavity of anesthetized flathead catfish through an incision made along the linea alba. The incision was closed with a single row of sutures through the peritoneum and dermis. Postoperative care included holding the fish in water with 50 mg/liter of oxytetracycline for 48-72 hours. After obtaining surgical experience, neither survival nor growth appeared to be affected by the surgery or by the presence of the transmitter. Flathead catfish with ultrasonic transmitters were tracked intermittently for as long as 40 days in Lake Carl Blackwell, Oklahoma. Behavior appeared to be normal after an initial adjustment period of about 36 hours, during which time movements seemed excessive. The same procedure was also used successfully on largemouth bass and striped bass.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1975)104<56:SPFIUT>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

Sex ratios are presented for 4,802 northern pike captured by nets, electrofishing, and angling from three Ontario populations. Anglers captured more female than male northern pike (1.24:1) and a higher ratio of female fish than were taken by other methods (1.14:1). Regardless of method or region of capture, sex ratios showed similar seasonal trends. Males were relatively more abundant during two seasons—spring and autumn—when the sex ratios were approximately equal. Often 1.5 to 2.0 times as many females as males were present during summer and winter in anglers' catches and net samples. There was no significant difference between either the summer (1.44:1) and winter (1.27:1), or the spring (1.04:1) and autumn (0.98:1), sex ratios. The sexes appear to have biannual peaks of availability which are related to activity and are independent of locality and method of capture.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1975)104<60:SRONPE>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor

摘要:

Effects of age, length, and age-length interaction on fecundity of the northern mottled sculpin, Cottus b. bairdi, were found to be significant (p = 0.05) and to follow a curvilinear relationship. A statistical model using age, and age-length interaction may be a more accurate predictive tool than a model based on length alone.

ISSN:0002-8487    

DOI:10.1577/1548-8659(1975)104<64:TROLAA>2.0.CO;2

出版商:Taylor & Francis Group    

年代:1975

数据来源: Taylor