scholarly journals Seasonal abundance and vertical distribution of siphonophores in western Norwegian fjords

2008 ◽  
Vol 30 (8) ◽  
pp. 951-962 ◽  
Author(s):  
A. Hosia ◽  
U. Bamstedt
Keyword(s):  
Vertical Distribution ◽  
Seasonal Abundance

Studies of the Biting-habits of African Mosquitos. An Appraisal of Methods employed, with special Reference to the twenty-four-hour Catch

1954 ◽  
Vol 45 (1) ◽  
pp. 199-242 ◽  
Author(s):  
A. J. Haddow
Keyword(s):  
Vertical Distribution ◽  
Special Reference ◽  
Geometric Mean ◽  
Seasonal Abundance ◽  
Central Tendency ◽  
Valuable Method ◽  
Different Seasons ◽  
Working Out ◽  
Different Levels ◽  
Biting Behaviour

It is felt that the 24-hour catch presents a valuable method of studying the biting-behaviour of mosquitos in the field, and further that conclusions concerning seasonal abundance, vertical distribution and times of biting-activity must be based on catches of this type if serious errors of interpretation are to be avoided.The time-divisions of the catch should not exceed one hour, and even shorter intervals may be desirable. Timing should be related to the actual times of sunrise and sunset. Where possible, a series of consecutive catches should be carried out, and a shift system must be carefully considered in relation to the particular series projected.Usually the results from different levels above ground should be treated separately in working out biting-cycles, and this may also apply to results from different seasons or different localities. Further, while in some instances the summation of long series of catches seems permissible, in others it is not, and in these detailed analysis of the figures may be necessary before consistent behaviour-patterns become apparent.In cases where a measure of the central tendency is to be employed, the geometric mean as modified by C. B. Williams appears to be the most suitable.

Seasonal abundance and vertical distribution of crab larvae from northern Patagonia (Argentina): implications for their transport in a biogeographic boundary region

2013 ◽  
Vol 10 (1) ◽  
pp. 37-50 ◽  
Author(s):  
Fernando Gaspar Dellatorre ◽  
Gustavo Lovrich ◽  
Laura Rojas ◽  
Viviana Milano ◽  
Nerina Delourdes Figueroa ◽  
...  
Keyword(s):  
Vertical Distribution ◽  
Boundary Region ◽  
Seasonal Abundance ◽  
Northern Patagonia ◽  
Crab Larvae

Seasonal Abundance and Vertical Distribution of Crab Larvae in Delaware Bay

Estuaries ◽  
1982 ◽  
Vol 5 (3) ◽  
pp. 197 ◽  
Author(s):  
Anna I. Dittel R. ◽  
Charles E. Epifanio
Keyword(s):  
Vertical Distribution ◽  
Delaware Bay ◽  
Seasonal Abundance ◽  
Crab Larvae

scholarly journals The Vertical Distribution of Marine Macroplankton. V. The Distribution of Animals Caught in the Ring-trawl in the Daytime in the Plymouth Area

1927 ◽  
Vol 14 (3) ◽  
pp. 557-608 ◽  
Author(s):  
F. S. Russell
Keyword(s):  
Vertical Distribution ◽  
Seasonal Distribution ◽  
External Factors ◽  
Calanus Finmarchicus ◽  
Seasonal Abundance ◽  
Optimum Level ◽  
Surface Layers ◽  
Present Purpose ◽  
The Vertical Distribution ◽  
Actual Depth

1. The vertical distribution of many species in daylight in the Plymouth area is shown, as a result of the examination of a number of serial hauls taken with the stramin ring-trawl between the dates April 2nd and August 6th, 1926.2. It is shown that probably the errors introduced by the employment of a non-closing net are for the present purpose negligible.3. The indications are that most species have an optimum level at which they live, in the daytime, the actual depth varying from day to day according to weather and other conditions.4. A few species appear to show no preference, being present equally abundantly at all depths or showing marked changes in the region of greatest abundance from day to day.5. A provisional list is given on page 567, showing the order in which many of the different species appear in greatest abundance from the surface downwards.6. The vertical distribution appears to differ for the two sexes of Calanus finmarchicus, the males tending to avoid the surface layers more than the females.7. The presence of the medusa Cosmetira pilosella in fair numbers in a catch in the daytime in the Plymouth region would seem to be a reliable indication that the net has been fishing below 20 metres.8. A catch of Calanus finmarchicus made by the stramin ring-trawl consists nearly always of over 80 per cent adults.9. No attempt has been made definitely to correlate behaviour with external factors: more observations are to be desired.10. Brief notes are given on the seasonal distribution of various species. The danger of drawing conclusions about seasonal abundance from daylight hauls only is shown by the results for Tomopteris helgolandica (p. 575).

scholarly journals The Seasonal Abundance and Distribution of the Pelagic Young of Teleostean Fishes Caught in the Ring-Trawl in Offshore Waters in the Plymouth Area

1930 ◽  
Vol 16 (3) ◽  
pp. 707-722 ◽  
Author(s):  
F. S. Russell
Keyword(s):  
Vertical Distribution ◽  
Seasonal Abundance ◽  
Young Fish ◽  
Good Basis ◽  
Trawl Fishing ◽  
Different Depths ◽  
Abundance And Distribution ◽  
The Vertical Distribution ◽  
Made In

A large number of collections were made with the 2-metre stramin ring-trawl in the years 1924, 1925 and 1926, to study the vertical distribution of young fish. Seeing that all these collections were made in exactly the same way, it was considered that they would form a good basis for a study of the quantitative differences in abundance of the different species at various times of the year. Accordingly, after 1926 the collections were supplemented in-1927, 1928 and 1929 by oblique hauls with the ring-trawl fishing at the same depths as those fished in the serial hauls in the study of the vertical distribution, that is the net was fished successively at the six different depths during half-an-hour's haul for 5 minutes at each depth. The results given in this report are all based on daylight catches.

scholarly journals Notes on Cyanea Caught in the Ring-trawl in the Plymouth Area during the Years 1925 to 1930

1931 ◽  
Vol 17 (2) ◽  
pp. 573-576 ◽  
Author(s):  
F. S. Russell
Keyword(s):  
Vertical Distribution ◽  
Seasonal Abundance ◽  
Young Fish ◽  
The Vertical Distribution

During the researches on the vertical distribution of plankton and on the-seasonal abundance of young fish, a record was kept of all Cyanea lamarcki Péron and Lesueur occurring in the catches of the 2-metre stramin ring-trawl. This was primarily for correlation with the abundance of such fish as the young whiting, Gadus merlangus, which at certain stages in. their development shelter under the umbrella of the medusa. Since it is only with the larger Cyanea that this association of the young whiting exists it was necessary to keep a record of the sizes of the Cyanea occurring in the catches. These were only rough measurements and denote the diameter of the flattened disc of the medusa usually to the nearest half-inch.

The seasonal abundance, vertical distribution, and relative microbial biomass of chroococcoid cyanobacteria at a station in southern California coastal waters

1981 ◽  
Vol 27 (12) ◽  
pp. 1341-1344 ◽  
Author(s):  
D. W. Krempin ◽  
C. W. Sullivan
Keyword(s):  
Microbial Biomass ◽  
Vertical Distribution ◽  
Coastal Waters ◽  
Southern California ◽  
Total Population ◽  
Standing Stock ◽  
Seasonal Abundance ◽  
Photic Zone ◽  
Early Fall ◽  
Chroococcoid Cyanobacteria

The standing stock of autofluorescent chroococcoid cyanobacteria (1 μm in diameter) paralleled the seasonal trends of phytoplankton and bacterioplankton at a station in southern California coastal waters. Low winter levels increased through the summer to peak levels in the early fall. The greatest number of autofluorescent cells was found within the top 30 m of the photic zone(0.1 × 107 to 7 × 107 cells∙L−1). Numerically, autofluorescent cells accounted for 3% of the total population of prokaryotes, while accounting for 20% of the total prokaryotic biomass. With respect to the total microbial (0.2–203 μm) biomass, the bacterioplankton averaged 5%; autofluorescent cells averaged 1%, with phytoplankton accounting for the remaining 94%.

Seasonal abundance and vertical distribution of mites in flat storage containing wheat

2006 ◽  
Vol 34 (1) ◽  
pp. 25-36 ◽  
Author(s):  
N. E. Palyvos ◽  
N. G. Emmanouel
Keyword(s):  
Vertical Distribution ◽  
Seasonal Abundance
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