Tag: vertical net

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Michael Gutiérrez Santiago: Newport Hydrographic Line, August 18, 2022

Lea esta publicación en español: Michael Gutiérrez Santiago: Línea Hidrográfica de Newport, 18 de agosto de 2022

NOAA Teacher at Sea

Michael Gutiérrez Santiago

 NOAA Ship Bell M. Shimada

August 12 – August 25, 2022


Mission: Pacific Hake Survey

Geographic Area of Cruise: Coasts of Washington and Oregon

Date: August 18, 2022


Weather conditions from the bridge:

Latitude: 4539.9725N
Longitude: 12422.9606W
Temperature: 63°F 
Wind Speed: 13 mph
Barometer:  1017.2mb

Michael poses for a photo to show off his gear: orange Grundens (rubber overalls) over a black sweatshirt, an orange life vest, a yellow hard hat, and sunglasses.
Ready for plankton sampling!

Science and Technology Log

Newport Hydrographic Line

One way scientists assess the health of our ocean’s ecosystems is to take samples of zooplankton and ichthyoplankton (fish eggs and larvae), both on the surface of the water and at depth. Observations of these plankton can inform us greatly about productivity at the bottom of the food chain, spawning location and stock size of adults, dispersal of larval fish and crabs to and away from nursery areas, and transport of ocean currents.

The Newport Hydrographic (Newport Line) is an oceanographic research survey conducted by NOAA’s Northwest Fisheries Science Center and Oregon State University scientists in the coastal waters off Newport, Oregon.

Researchers have collected physical, chemical, and biological oceanographic metrics along the Newport Line every two weeks for over 20 years. This twenty-plus year dataset helps us to understand the connections between changes in ocean-climate and ecosystem structure and function in the California Current.

Data from the Newport Line are distilled into ocean ecosystem indicators, used to characterize the habitat and survival of juvenile salmonids, and which have also shown promise for other stocks such as sablefish, rockfish, and sardine. These data also provide critical ecosystem information on emerging issues such as marine heatwaves, ocean acidification, hypoxia, and harmful algal blooms.

a map of the coast of Washington and Oregon. the land is shaded gray, while the water includes a few blue lines indicating underwater topography. Though there are not grid lines, labels mark the latitude lines from 43 degrees North to 47 degrees North and the longitude lines from 125 degrees West to 123 degrees West. Midway, between 44 and 45 degrees North, a short red line extends horizontally out from Newport to the 125th meridian. It's labeled "NH Line"
Newport line

Barometer of ocean acidification and hypoxia in a changing climate

Global climate models suggest future changes in coastal upwelling will lead to increased incidence of hypoxia and further exacerbate the effects of ocean acidification. The Newport Line time-series provides a baseline of biogeochemical parameters, such as Aragonite saturation state—an indicator of acidic conditions. Researchers can compare this baseline against possible future changes in the abundance of organisms (e.g., pteropods, copepods and krill) sensitive to ocean acidification and hypoxia.

Equipment used

  • a net, which includes long mesh tubing extending from a ring, hangs in the air from a point above the photo's frame. a crewmember, wearing hard hat and life jacket, grips the ring with his left hand and reaches toward a rope attached to the net with his right hand. three other crewmembers are visible around the net.
    Vertical/half meter net
  • a net, which includes long mesh tubing extending from a ring, hangs in the air from a point above the photo's frame. a crewmember, wearing hard hat and life jacket, facing away from the camera, reaches over the rail of the ship to lower the end of the suspended net into the water.
    Getting the vertical net in the water
  • an illustration of a research vessel with a vertical net deployed off its side. the net looks like a white cone, pointing downward, ending in a red cannister.
    Vertical net deployed vertically in the water from a research vessel

A vertical net is a ring net with a small mesh width and a long funnel shape. At the end, the net is closed off with a cylinder (cod-end) that collects the plankton. It is deployed vertically in the water from a research vessel. It is mostly used to investigate the vertical/diagonal stratification of plankton. This allows the abundance and distribution of mesozooplankton to be determined.

  • a cable lowers a bongo net onto the ship's deck. the bongo net, name for bongo drums, is actually a pair of nets: two rings side by side hold up the nets made of long mesh tubing that narrow until they end in attached cannisters. a crewmember, wearing a hard hat and a life vest, leans to look at something around the back of the net.
    Bongo net
  • a crewmember, wearing a hard hat and life vest, hoses down the mesh tubing of one side of the bongo net. the top of the net hangs from a cable about 12 feet above the deck so the crewmember can rinse the tubing while standing.
    Washing the sample down the bongo net
  • an illustration of a research vessel with a bongo net deployed off its stern. the net looks like a pair of white cones, pointing horizontally away from the ship, ending in red cannisters.
    A bongo net is drawn horizontally through the water column by a research vessel

A bongo net consists of two plankton nets mounted next to each other. These plankton nets are ring nets with a small mesh width and a long funnel shape. Both nets are enclosed by a cod-end that is used for collecting plankton. The bongo net is pulled horizontally through the water column by a research vessel. Using a bongo net, a scientist can work with two different mesh widths simultaneously.

  • Michael, at left, holds up the net while Toby, right, uses a hose to spray down the mesh tubing at the end. Both Michael and Toby wear rubber pants, rubber boots, life jackets, and hard hats.
    Assisting Toby with Isaacs-Kidd net
  • three crewmembers, wearing hard hats and life vests, hold different portions of a large fishing net that is attached to cables extending out of frame. One steadies the net spreader, a horizontal metal bar. Another grasps the webbing. We can see a wide piece of metal toward the front that is bent like a wide "V". The belts of the crewmembers' vests are each clipped to brightly covered, stretchy tethers to prevent them from falling overboard.
    Isaacs-Kidd midwater trawl
  • a diagram of the shape and dimensions of the Isaacs-Kidd midwater trawl. labels identify the net spreader (horizontal metal bar), depresser (v-shaped metal plate), and bridle (short cables extending from the edges of the net opening, coming to a point). the net opening is 4 feet 8 inches wide by 5 feet 9 inches tall. the main portion of the trawl net extends 20 feet 6 inches long; it attached to a finer mesh net that is 5 feet 8 inches long.
    Isaacs-Kidd midwater trawl dimension

Isaacs-Kidd midwater trawl collects bathypelagic biological specimens larger than those taken by standard plankton nets. The trawl consists of the specifically designed net attached to a wide, V-shaped, rigid diving vane. The vane keeps the mouth of the net open and exerts a depressing force, maintaining the trawl at depth for extended periods at towing speeds up to 5 knots. The inlet opening is unobstructed by the towing cable.

What we got?

a close-up view of a hand holding a clear jar with a white lid. This jar contains the sample collected by the vertical net. Since this net targets plankton, the sample mostly looks like cloudy, yellowish water.
Samples from vertical net
a close-up view of the contents of a white container, perhaps a bucket. This contains the sample collected from the bongo net. It's a soupy mixture of plankton, zooplankton, krill, and at least one small fish.
Samples from bongo net
  • a close-up (possible magnified) view of a petri dish containing organisms sampled by the Isaacs-Kidd net. mostly crustaceans and larval fish. The petri dish rests on a bright blue background that creates a sharp contrast with the somewhat translucent creatures.
    Isaacs-Kidd sample
  • close-up view of a pile of many, many krill. they look like clear pink tubes with black dots for eyes.
    Krill from the Isaacs-Kidd

Personal Log

SHARK ATTACK!

That’s right, our underway CTD was attacked by a shark.

a view through a metal rigging of a pully with a cable extending down to the ocean's surface. there is no longer anything attached to the cable.
R.I.P.

On a bright and sunny day, the science team decided to launch the underway CTD, but things didn’t go as planned! Retrieving the uCTD back to the ship we saw a big dorsal fin zigzagging close to the uCTD, until we noticed that the uCTD was no longer attached to the line, therefore we had no choice that to cancel the uCTD. You should have seen all of our faces; we couldn’t believe what we saw. We think it could have been a:

a stock image of a white shark swimming underwater.
White shark
a stock image of a salmon shark swimming underwater.
Salmon shark
view of a hand holding an underwater conductivity, temperature, and depth (uCTD) profiler. in the background is a painting on a cabinet door of a white ship sailing through waves and somewhat fantastical deep sea creatures swimming below.
underway CTD
(what the shark ate)

CTD stands for conductivity (salinity), temperature, and depth and it enables researchers to collect temperature and salinity profiles of the upper ocean at underway speeds, to depths of up to 500 m. Ocean explorers often use CTD measurements to detect evidence of volcanoes, hydrothermal vents, and other deep-sea features that cause changes to the physical and chemical properties of seawater.

Sunset on the Pacific Ocean, as seen from an upper deck of NOAA Ship Bell M. Shimada. The trawl net frame, davits, and other equipment on the fantail are visible in silhouette.
Sunset on board
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Justin Czarka, August 14, 2009

NOAA Teacher at Sea
Justin Czarka
Onboard NOAA Ship McArthur II (tracker)
August 10 – 19, 2009 

Mission: Hydrographic and Plankton Survey
Geographical area of cruise: North Pacific Ocean from San Francisco, CA to Seattle, WA
Date: August 14, 2009

Weather Data from the Bridge 

Sunrise: 6:29 a.m.
Sunset: 2033 (8:33 p.m.)
Weather: patchy mist
Sky: partly to mostly cloudy
Wind direction and speed: Northwest 10-15 knots (kt)
Visibility: unrestricted, reduced to 1-3 nautical miles (nm) in mist
Waves: northwest 3-6 feet
Air Temperature: 17.50°C
Water Temperature: 17.63°C

Science and Technology Log 

Today I rotated to a new job assignment. I have been working with the CTD water samples, storing nutrient samples, and preparing chlorophyll samples.  Now I work with Jay Peterson, researcher from Oregon State University, Hatfield Marine Science Center, Newport, Oregon, deploying, retrieving, and preparing live samples from the vertical net and bongo net on a cable.

The vertical net gets rinsed off after the tow.
The vertical net gets rinsed off after the tow.

The nets collect all types of plankton, both plants and animals.  As with all the sample collections occurring aboard the McArthur II, communication is the backbone of the operations, or “ops.” For the vertical net and bongo net, two people manually place the nets over the ship’s starboard side, while a winch operator deploys and retrieves the nets from the ocean, and the bridge navigates the ship. For vertical nets, the goal is to take the net to 100 meters (m) depth and then hauled up vertically. The purpose is to catch organisms from the entire water column up to the surface.  It is the same depth for the bongo net, but the goal is to have the cable at a 45° angle with the ship moving at a steady 2 knots (kt). Both nets have flowmeters to determine the volume of water that goes through the net. Once back on the deck, the nets are rinsed from the top to the bottom so that everything in the net can be analyzed. The samples are placed in jars or buckets to observe under microscope.  We find euphausiids (krill), copepods, Tomopteris, Chaetognatha (arrow worms), fish larvae, Phronima, and even bird feathers!  You have to check out these animals online, as they all have fascinating features. More importantly, while small in size, they are an essential part of the food web. Without them, many species would struggle to find food.

Personal Log 

Today we a day of plenty in terms of sighting marine mammals and other species as well!  The day started out near shore at Newport, Oregon and the Yaquina Head Lighthouse.  The McArthur II travels roughly in a zigzag approach near shore to off shore and back for this mission.  Getting ready for the day watch, I saw some whales off the port (left side facing forward on a ship). That was just the beginning. As we headed due west on the Newport transect line (44 39.1′ N latitude) we spotted brownish and reddish jelly fish, albatross following along the starboard side during bongo tows, sea lions skirting by the stern, and a shark fiddling with driftwood presumably looking for small fish that were utilizing the log as a habitat. Later in the day, we navigated near breaching humpback whales on the starboard side. Towards evening, a group of 5-6 pacific white-sided dolphins followed along for 10 minutes or so.

A Doliolid, which feeds on plankton, was caught in the vertical net before being released into the ocean. Note the pinkish lines, the muscle bands, and blimp-like shape.
A Doliolid, which feeds on plankton, was caught in the vertical net before being released into the ocean. Note the pinkish lines, the muscle bands, and blimp-like shape.

Being out here witnessing the wildlife in their environment is fascinating.  You start to internalize the ocean planet as more than a vast emptiness.  There exists a tremendous amount of species diversity living above and below the surface. Yet sadly, since few of us spend regular time away from our land habitats, we tend to neglect the essential nature of the ocean.  The ocean truly sustains us, whether providing the majority of our freshwater (through evaporation and, consequently, rain), supporting our nutritional diets, and driving the weather we experience daily.  Teacher at Sea really reinforces this revelation since I get to spend an extended amount of time away from my terrestrial existence learning to appreciate the ocean’s influence on our lives.  May we gain enough understanding to ensure the sustainability of the ocean ecosystem.

Animals Seen 

Humpback whales
Shark
Jellyfish
Doliolid
Albatross
Albacore tuna
Sea lion
Pacific white-sided dolphin