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Biology 124 Biological Oceanography
Online Project

TOOLS OF THE OCEANOGRAPHER: Equipment: Animal & Plant Samplers

A.  Taking Samples of the Marine Environment
1. Water Samplers
• Van Dorn Bottle
• Nansen Bottle
• Niskin Bottle
• JZ Bacterialogical Bottle
• Surface Sample Bottle
2. Messengers
Most of the water samplers can be sent to a particular depth and then "triggered" to take the water sample by a "messenger". This is also the case with several other types of samplers (bottom, organism).
3. Bottom Samplers
• Ekman Grab
• Petersen Grab
• Soft Bottom Modified Petersen Grab
• Wash Bucket
• Bottom Corer
4. Animal and Plant Samplers
• Plankton: Standard Plankton Net, Deck Plankton Collector, Folsom Plankton Splitter, Sedgewick-Rafter    Plankton Counting Chamber
• Succession Plates
• Transects
• Quadrants
• Biological Dredge
• Beach Seine
• Otter Trawl
• Isaacs-Kidd Midwater Trawl

4. Animal and Plant Samplers to top of page
Standard Plankton Net
Standard Plankton Net

Standard Plankton Net

Samples: Plankton
Operates: On a cable or line by hand or behind a boat.
Notes: Can be towed vertically or horizontally, some have meters that record the volume of water passing through the net, others have a device to keep the mouth of the net closed until it reaches a certain depth and then to close it after the tow

Plankton nets come in a variety of sizes (from this relatively small net to nets with the mouth over 10 feet across. The size of the openings (apertures) in the net itself also vary and are used to describe the net as follows:

Mesh Number 00 equals an aperture of .030 inches.
0 .023
2 .015
6 .0096
12 .0047
20 .0030
25 .0025


Deck Plankton Collector to top of page
Deck Plankton Collector
Samples: Plankton
Operates: On the deck of a boat or float with a pump that pumps water from a particular depth through the net letting the overflow return to the ocean
Notes: Generally a slow process and not as efficient as the Satandard Plankton Net however it is good when plankton from a particular depth is needed as the pump can be turned on only when at a certain depth

Folsom Plankton Splitter to top of page
Folsom Plankton Splitter
Samples: To split plankton samples equally so that the material in the sample near the surface and near the bottom is equally split
Operates: By rotating a plankton sample in the enclosed drum
Notes: Can be used again and again to get smaller and smaller subsamples

Sedgewick-Rafter Plankton Counting Chamber to top of page
Sedgewick-Rafter Plankton Counting Chamber
Used: To view1 ml plankton of a plankton sample
Operates: Under the microscope
Notes: By counting and recording only 1 ml of a large plankton sample it is possible to estimate the numbers of plankters in the entire sample in a short period of time

Succession Plates to top of page
Succession Plates
Samples: Fouling organisms in the ocean
Operates: By placing these (or any solid material) in the ocean for a period of time
Notes: Plates can be withdrawn periodically to determine the "succession" or organisms that settle and grow there

Transects to top of page
Transects

transect line at the tidepools
Used: To describe (usually by counting and recording rather than taking) organisms in an environment in reference to a line (rope or tape measure)
Operates: In any environment by hand
Notes: Several types of transects can be used depending on the environment and time to do the study. Line transects are done by recording all organisms touching the line, strip transects are done by recording all organisms within a certain distance of the line, and spot transects are done by recording all organims found at certain points along the line.

Quadrats to top of page
Quadrats
Used: To describe (usually by counting and recording rather than taking) organisms in an environment found within a the perimeter of a certain sized material
Operates: In any environment by hand
Notes: Several types of quadrats can be used, large or small, square, round or triangular, etc. The one we will use is a square or rebar that is 1/2 meter on each side so the quadrat is 1/4 of a square meter.

Biological Dredge to top of page
Biological Dredge
Samples: Organisms living on a rocky bottom
Operates: At any depth on a cable or line (generally with a hydraulic winch)
Notes: Often rips specimens off and can be destructive

Beach Seine to top of page
pulling the beach seine
pulling the beach seine
viewing the beach seine catch
viewing the beach seine catch
Samples: Organisms living on a sandy bottom near shore
Operates: From the shore to about 15 feet of water by hand (many people)
Notes: Outlawed for most uses, a special State permit is hard to get

Otter Trawl to top of page
end of otter  trawl 70' net
End of otter trawl 70' net.
Otter trawl catch
Otter trawl catch
Samples: Organisms on or near (within a few feet) sandy or muddy bottoms
Operates: At any depth by cable or line by hand or hydraulic winch
Notes: Used by fishermen for flatfish (sole, halibut, flounder) and shrimp
This is the net we will use in our trawl lab (it is too big to bring into lab)

Isaacs-Kidd Midwater Trawl to top of page
model of Isaacs-Kidd Midwater Trawl
Samples: Organisms in the water column
Operates: At any depth (not on the bottom) on a cable or line by hydraulic winch
Notes: This is a model of the net, most are at least 10-15 feet square at the mouth


 
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