摘要:

A system for maintaining midwater fishes in captivity is described. The system employs a darkened, round-bottom boiling flask containing a structured flow of sea water. Damaging results of the fishes’ characteristic escape responses are prevented. Dipnetted specimens ofTarletonbeania crenulariswere maintained aboard ship and ashore for periods of up to 72 hr.

ISSN:0706-652X    

DOI:10.1139/f73-021

出版商:NRC Research Press    

年代:1973

数据来源: NRC

摘要:

A modified stake net for collecting smolts of Atlantic salmon (Salmo salar) is described. The net is efficient for trapping smolts and, in addition, it practically eliminates problems with mortality of captured fish and accumulation of debris in the trap.

ISSN:0706-652X    

DOI:10.1139/f73-022

出版商:NRC Research Press    

年代:1973

数据来源: NRC

摘要:

Observations on 86 tagged mosshead sculpins (Clinocottus globiceps) show that this species exhibits fidelity to specific tide pools and returns to them when displaced to other tide pools.

ISSN:0706-652X    

DOI:10.1139/f73-023

出版商:NRC Research Press    

年代:1973

数据来源: NRC

摘要:

An 1835 record of the sea lamprey (Petromyzon marinus) in Lake Ontario is related to a hypothesis that it entered the lake through the Erie Canal after 1819.

ISSN:0706-652X    

DOI:10.1139/f73-024

出版商:NRC Research Press    

年代:1973

数据来源: NRC

摘要:

Otter-trawl records and midwater-trawl catches suggested that some mesopelagic fishes are permanent members of the midwater fauna of the Gulf of Maine rather than strays.Benthosema glaciale,Ceratoscopelus maderensis,Myctophum punctatum, andMaurolicus muelleri, cold water or ubiquitous species, occur in the Gulf throughout the year, and warmwater species derived from adjacent Slope Water offshore were captured in the Gulf during the summer and fall. Nine species of mesopelagic fishes are here recorded from the Gulf for the first time.

ISSN:0706-652X    

DOI:10.1139/f73-025

出版商:NRC Research Press    

年代:1973

数据来源: NRC

摘要:

The elapsed time from fertilization through hatching for steelhead trout (Salmo gairdneri) was obtained from groups of eggs that were fertilized according to a factorial breeding plan in which 24 males were each mated to each of 10 females. Data were obtained from the eggs of 240 crosses held in an incubator through hatching and from replicated crosses held in an incubator for most of the incubation period, then in troughs. Estimated heritabilities for hatching time were 0 and 0.23, respectively, for these data, the differences being of additive genetic origin. Because of a significant genotype–environment interaction, it was suggested that hatching may have been controlled by different genetic mechanisms in the two environments.

ISSN:0706-652X    

DOI:10.1139/f73-026

出版商:NRC Research Press    

年代:1973

数据来源: NRC

摘要:

not available

ISSN:0706-652X    

DOI:10.1139/f73-027

出版商:NRC Research Press    

年代:1973

数据来源: NRC