food web – Page 2 – NOAA Teacher at Sea Blog

August 28, 2010April 22, 2021

Natalie Macke, August 28, 2010

NOAA Teacher at Sea: Natalie Macke
NOAA Ship: Oscar Dyson

Mission: BASIS Survey
Geographical area of cruise: Bering Sea

Date: 8/28/2010

It’s Fish Feeding Time…

Weather Data from the Bridge :

Visibility : <0.5 nautical miles (Wondering what a nautical mile is??)

Wind Direction: From the W at 20 knots

Sea wave height: 2-3ft

Swell waves: WSW, 4ft

Sea temp:9.1 oC

Sea level pressure: 1013.0 mb

Air temp: 9.7 oC

Science and Technology Log:

DSCN0314 — Euphausiid Specimens (zooplankton)

We’re up to station #40 now and everyone certainly has their routine down. One type of sampling I have yet to cover is the microscopic life; the base of the food web. A look at the marine fisheries food web quickly reveals that in order to support the commercial fisheries as well as the vast number of marine mammals and ocean birds, there must be an abundance of phytoplankton and zooplankton available in the Bering Sea. Evidence of this food chain is demonstrated by dissecting the stomach of a salmon. The sample (in the picture below) revealed that the salmon had recently dined on euphaussids (commonly known as krill). Before getting into how the zooplankton samples are collected, first let me go back and touch on the base of the food web; phytoplankton. These samples are collected from the Niskin bottles on the CTD each cast. The samples are preserved with formalin and will be brought back to the lab for further analysis. Now, back to the critters..

At every sampling station on the side deck and immediately after each CTD cast, zooplankton net tows are completed. There are three different tows being used for the BASIS survey. The first two are vertical tows where nets that are weighted are dropped to the seafloor and then brought back to the surface thus sampling a vertical water column. The pairovet, named from the fact that is was designed as a “pair of vertical egg tows” (designed to collect pelagic egg samples) has a netting mesh size of 150 microns. The net is simply deployed with a weight on the bottom. When it reaches the deepest part of the water column it is brought back to the surface collecting its’ sample. Another similar net with a 168 micron mesh size is named the Juday. Once either of these nets is brought to the deck, it is washed down and anything caught is captured in the cod end (the name for the PVC bucket at the bottom of the net).

Page_1_2 — Deploying the Bongo nets off the starboard side

The last type of tow that is completed for the BASIS survey uses the Bongo nets. This tow is considered an oblique tow since the nets essentially are lowered to about 5m from the ocean bottom and towed for a certain length of time. If you remember from the acoustics, in daylight hours the zooplankton migrate to the ocean bottom to hide from their prey. Since our sampling is done in daylight hours, the deep sampling depth is where we expect to find the highest density of zooplankton sample. The mesh sizes on the two nets of the Bongo are 335 and 505 microns. This allows for sampling of zooplankton of different sizes. The samples are collected on board and then taken back to the lab for analysis. They are separated by species, counted and weighed. Biomass and species composition is determined for each sample. The majority of the zooplankton we have seen this cruise have been euphaussids and copepods of varying types.

Oh where, oh where does the Internet go??

So as August winds down and the school year gears up, my connection to the Internet is becoming more and more important. Since my Oceanography class is with the Virtual High School, I have to essentially set up my virtual classroom in these upcoming days. I’ll assume my esteemed colleagues will assist me in unpacking lab equipment back at home at my physical classroom. (Even though I know.. all my orders will mysteriously wind up in other labs, I’m assured they’ll be safely placed away.)

So I tracked down Vince Welton, our Electronic’s Technician for some help understanding why sometimes I can surf, and why sometimes I can’t….

Simple…

Our Internet connection is via the geostationary satellite GE 23 at 172 degrees East. This satellite transmits over most of the Pacific Ocean (see a coverage map). Since this satellite is positioned on the equator, that means our receiver must look essentially due south for a signal. When our ship is northbound, the mast and stack of the Oscar Dyson simply gets in the way. Therefore… no Internet on northbound travels.

The Oscar Dyson also has access to two Iridium satellites for communication as well as the GE 23. These are the SAT-B which can transmit both data and voice communications and the VSAT which only allows voice transmission. The ship can access this set of orbiting satellites when the GE 23 is unavailable due to course of travel or weather conditions.

Personal Log

Yesterday, I got permission to stay on the trawl deck during one of our station trawls. It was fun to be outside down with the net. Jeanette helped do some taping which I hope to(during a few Internet-less days ahead) compile to a video for my classes. Of course as fate would have it, our catch for the day (shown below) was not one for the record books or even worth remembering at all.. I guess that’s what the editing process is for hmmm…

In the Oceanography lab, we have started our primary productivity experiments and chlorophyll analysis so learning these new procedures has been interesting and given me lots of ideas for some research topics for Edelberg’s class. All in all, I am enjoying watching, learning and doing science here in eastern Bering Sea. One week left..

August 15, 2009April 6, 2021

Justin Czarka, August 15, 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 15, 2009

Weather data from the Bridge

*This picture shows what happens to an 8 fluid ounce Styrofoam cup after experience water pressure at 1000 meters down. The colorful cup was sent down attached to the CTD*

Sunrise: 6:29 a.m.
Sunset: 20:33 (8:33 p.m.)
Weather: patchy mist
Sky: partly to mostly cloudy
Wind direction and speed: north-northwest 15-20 knots (kt), gust to 25 kt
Visibility: unrestricted to 1-3 nautical miles in mist
Waves: northwest 6-9 feet
Air Temperature: 18°C high, 12°C low
Water Temperature: 17.5°C

Science and Technology Log

Today we made it out to 200 miles off the Oregon Coast; the farthest out we will go. The depth of the ocean is 2867 meters (9,406 feet). It is pretty interesting to imagine that we are on the summit of a nearly 10,000-foot mountain right now! Last night the CTD was deployed 1,000 meters (3,281 feet). Even at this depth, the pressure is immense (see photo, page one). When taking the CTD down to this depth, certain sensors are removed from the rosette (the white frame to which the CTD instruments are attached) to prevent them from being damaged.

Justin Czarka taking observational notes while aboard the McArthur II. These notes preserve the knowledge gained from the NOAA officers and crew, as well as the researchers

The crew aboard the McArthur II is such an informative group. Many possess a strong insight into NOAA’s research mission. Today I spoke with Kevin Lackey, Deck Utility man. He spoke to me about the cruises he has been on with NOAA, particularly about the effects of bioaccumulation that have been studied. Bioaccumulation is when an organism intakes a substance, oftentimes from a food source, that deposits in the organism at increasing levels over time. While sometimes an intentional response from an organism, with regards to toxins, this bioaccumulation can lead to detrimental effects. For example, an organism (animal or plant) A on the food web experiences bioaccumulation of a toxin over time. Imagine organism B targeting organism A as a food source. Organism B will accumulate concentrated levels of the toxin. Then, when organism B becomes a food source for organism C, the effects of the toxins are further magnified. This has serious effects on the ocean ecosystem, and consequently on the human population, who rely on the ocean as a food source.

While aboard the McArthur II, Morgaine McKibben, a graduate student at Oregon State University (OSU), shared with me her research into harmful algal blooms (HABs), which potentially lead to bioaccumulation. Certain algae (small plants) accumulate toxins that can be harmful, especially during a “bloom.” She is collecting water samples from the CTD, as well as deploying a HAB net, which skims the ocean surface while the ship is moving to collect algae samples. She is utilizing the data in order to create a model to solve the problem of what underlying conditions cause the algae blooms to become toxic, since they are not always as such.

Personal Log

Sunset over the Pacific Ocean from the flying bridge off the coast of Heceta Head, Oregon (N 43°59, W 124°35) a half hour later than two nights ago!

The weather has cleared up allowing grand ocean vistas—a 360° panorama of various blues depending on depth, nutrients, clouds overhead, and so forth. At first glance, it just looks blue. But as you gaze out, you see variance. A little green here, some whitecaps over there. As the ship moves on, the colors change. Wildlife appears, whether it is a flock of birds, kelp floating by, or an escort of pacific white-sided dolphins. I wondered if the ocean would become monotonous over the course of the eleven days at sea. Yet the opposite has happened. I have become more fascinated with this blue water.

It was interesting today to notice how we went back in time. Two nights ago the sun had set at 20:03 (8:03 p.m.) But because we went so far out to sea, last night the sunset had changed to 20:33 (8:33 p.m.). While this happens on land as well, it never occurred to me in such striking details until out to see.

Animals Seen from the Flying Bridge (highest deck on the ship)

Rhinoceros Auklet – closely related to puffins
Whale (breaching)
Common Murres
Western Gull
Hybrid Gull – We are at a location off the coast of Oregon where different species interbreed
Leech’s Storm Petrel – Mike Force, the cruise’s bird and marine mammal observer, found the bird aboard the ship by in an overflow tank. It will be rereleased.

Did You Know?

NOAA has a web page with information especially for students?

July 28, 2009April 6, 2021

Kathryn Lanouette, July 28, 2009

NOAA Teacher at Sea
Kathryn Lanouette
Onboard NOAA Ship Oscar Dyson
July 21-August 7, 2009

Here I am sorting different zooplankton species

Mission: Summer Pollock Survey
Geographical area of cruise: Bering Sea, Alaska
Date: July 28, 2009

Weather Data from the Ship’s Bridge
Visibility: 8 nautical miles
Wind direction: 015 degrees (N, NE)
Wind speed: 7 knots
Sea wave height: 1 foot
Air temperature: 7.6˚C
Seawater temperature: 7.3˚C
Sea level pressure: 29.8 inches Hg and falling
Cloud cover: 8/8, stratus

Science and Technology Log

In addition to studying walleye pollock, NOAA scientists are also interested in learning about the really tiny plants (phytoplankton) and animals (zooplankton) that live in the Bering Sea. Plankton is of interest for a two reasons. First, phytoplankton are the backbone of the entire marine food chain. Almost all life in the ocean is directly or indirectly dependent on it. By converting the sun’s energy into food, phytoplankton are the building blocks of the entire marine food web, becoming the food for zooplankton which in turn feed bigger animals like small fish, crustaceans, and marine mammals. Second, zooplankton and small fish are the primary food source for walleye pollock. By collecting, measuring, and weighing these tiny animals, scientists are able to learn more about the food available to walleye pollock. In addition, every time the scientists trawl for walleye pollock, the stomachs of 20 fish are cut out and preserved. Back at a NOAA lab in Seattle, the contents of these fish stomachs will be analyzed, giving scientists a direct connection between walleye pollocks’ diet and specific zooplankton populations found throughout the Bering Sea.

A simplified marine food chain (Note: A complete marine food web involves hundreds of different species.)

Two important zooplankton groups in the Bering Sea are copepods and euphausiids (commonly referred to as krill). Euphausiids are larger and form thick layers in the water column. In order to catch euphausiids and other zooplankton of a similar size, a special net called a Methot is lowered into the water. This fine meshed net is capable of catching animals as small as 1 millimeter. The same sonar generated images that show walleye pollock swimming below the water’s surface are also capable of showing layers of zooplankton. Using these images, the scientists and fishermen work together, lowering the net into the zooplankton layers.

The Methot net is the square shaped net in the background. It was just brought up and is filled with hundreds of zooplankton.

Once the Methot net is back onboard the boat, its contents are poured through fine sieves and rinsed. All species are identified. A smaller sub sample is weighed and counted. This information is applied to the entire catch so if there were 80 krill, 15 jellyfish, and 5 larval fish in a sub sample, then scientists would approximate that 80% of the entire catch was krill, 15% was jellyfish, and 5% was larval fish. Having only seen photos of some of these zooplanktons, it was interesting to hold them in my hands and look at them up close. They seemed better suited for space travel or a science fiction movie than the Bering Sea!

Personal Log

The day before, I caught my first glimpse of Dall’s porpoises. This pod of porpoises came swimming alongside the boat. It was awesome to see their bodies rise and fall in the water. I was surprised at how quickly they were swimming, darting in and out of the Oscar Dyson’s wake. Today, I also got my first glimpse of a whale! It was a fin whale, a type of baleen whale, about 20 meters from the boat. It was exciting to watch such a large mammal swimming in such a vast expanse of water. I’m hoping to see a few more marine mammal species before we return to port. The seas have been very calm for the last five days, at times as smooth as a mirror. I’m surprised that I’ve gotten used to falling asleep in the early morning hours and waking around midday. Now that I’ve adjusted to the 4pm to 4am shift, I’m wondering how strange it will be to return to my regular schedule back on the east coast.

Answer to July 25^th Question of the Day: Why are only some jellyfish species capable of stinging?
As I picked up my first jellyfish in the wet lab (asking at least twice “Are you sure this won’t sting?”), I wondered why some jellyfish don’t sting. So I did some reading and asked some of the scientists a few questions. Here is what I found out: All jellyfish (called “gelatinous animals” in the scientific world) have stinging cells (nematocysts) in their bodies. When a nematocyst is touched, a tiny barb inside fires out, injecting toxin into its prey. It seems that in some jellyfish, the barbs are either too small to pierce human skin or that nematocysts don’t fire when in contact with human skin.

One euphausiid and two different species of hyperiid amphipod (They are between 1-3 cm long) — One euphausiid and two different species of hyperiid amphipod

Animals Seen
Capelin, Dall’s porpoise, Euphausiid, Fin whale, Hyperiid amphipod, and Slaty-backed gull.

New Vocabulary: Baleen whale – a whale that has plates of baleen in the mouth for straining plankton from the water (includes rorqual, humpback, right, and gray whales). Methot net – a square framed, small meshed net used to sample larval fish and zooplankton. Phytoplankton – plankton consisting of microscopic plants. Plankton – small and microscopic plants and animals drifting or floating in the sea or fresh water. Trawl – to fish by dragging a net behind a boat. Zooplankton – plankton consisting of small animals and the immature stages of larger animals

Question of the Day: How has the walleye pollock biomass changed over time?

May 17, 2009April 5, 2021

Elise Olivieri, May 17, 2009

NOAA Teacher at Sea
Elise Olivieri
Onboard Research Vessel Hugh R. Sharp
May 9 – 20, 2009

Mission: Sea Scallop Survey
Geographical area of cruise: Northwest Atlantic
Date: May 17, 2009

Weather Data from the Bridge
Air Temperature: 13.61 Degrees Celsius
Barometric Pressure: 1012 mb
Humidity: 97 %

Here you can see the many different sizes of sea scallops.

Science and Technology Log

So Far the sea scallop survey has collected 76,170 sea scallops which can also be expressed as 9,251 kilograms. This is a tremendous amount of scallops and the survey is not even a third of the way complete. At stations where crabs and starfish were sampled we have collected 8,678 cancer crabs and 279,768 starfish (Asterias) so far. Without a reliable database like FSCS it would be impossible to keep up with such a large amount of information.

Today I got a chance to talk with Shad Mahlum. He is a seagoing technician for NOAA and was born and raised in Montana. He has experience working with freshwater surveys. In the past years he has studied how beaver dams influence native and non-native species of freshwater fish. Shad also spent some time looking at various cattle grazing strategies and how they affect food chains. Shad loves working on the open ocean and the physical process of sea scallop surveys. Shad hopes to work with freshwater and saltwater projects in the future.

Here I am holding a scallop and a Red Hake.

As I was gazing out into the deep blue sea a very large animal caught my eye. I was so excited to see another Finback Whale. They are the second largest animal on earth after the Blue Whale. They are known to grow to more than 85 feet. Finbacks are indifferent to boats. They neither approach them nor avoid them. Finback Whales dive to depths of at least 755 feet. They can grow anywhere from 30-80 tons. Finbacks eat Krill, fish and squid and their population numbers are approximately 100,000 or more. The only threats Finbacks have are polluted waters. It is incredible to see such a large animal breaching out of the water. I will never forget it.

Animals Seen Today

Wrymouth Squid, Eelgrass Slug, Razor Clam, Lobsters, Green Sea Urchin, Macoma clam, Sea Stars (Asterias), Horseshoe Crab, Fourbeard Rockling, Palmate Sponge, Hermit Crab, Black Clam, Golden Star, Tunicate, Winter Flounder, Surf Clam, Yellowtail Flounder, and Sea Mouse.

July 21, 2007April 1, 2021

Methea Sapp-Cassanego, July 21, 2007

NOAA Teacher at Sea
Methea Sapp-Cassanego
Onboard NOAA Ship Delaware II
July 19 – August 8, 2007

Mission: Marine Mammal Survey
Geographical Area: New England
Date: July 21, 2007

Weather Data from Bridge
Visibility: 7nm
Wind Direction: West-northwest
Wind Speed: 5-10 mph
Swell height: 6 to 8 feet

Peter Duley stands with the vertical profiling package, which is the property of Dr. Mark Baumgartner, Woods Hole Oceanographic Institution.

Science and Technology Log

Yesterday and today were spent traveling down 3 transect lines. Each transect line is a total of 18 miles long and sits 5 miles apart from its neighboring transect. The 3 transects are further divided into stations so that each transect contains 6 stations which are evenly spaced by three miles. The boats captain and crew ensure that the boat is correctly positioned according to the transects and stations. Upon arrival at a given station the bridge radios the dry lab and preparations begin in order to launch an instrument called a vertical profiling package. The vertical profiling system on board the DELAWARE II is the property of Dr. Mark Baumgartner of the Woods Hole Oceanographic Institution and is operated by Melissa Patrician, Oceanographic Technician at Woods Hole Oceanographic Institution.

This trio of instruments is bolted to the inner rim of a round aluminum cage that helps protect the sensitive instruments and allows multiple instruments to be lowered in one convenient package. Three instruments are on this particular cage: One is a conductivity, temperature, depth (CTD) sensor which also happens to measure phytoplankton concentrations via a fluorometer. The second implement is an optical plankton counter (OPC). This instrument functions by projecting a beam of light against a sensor plate. When particles (marine snow, copepods, krill, or other types of plankton) pass in front of the sensor plate they block the beam of light and are thus recorded by a remote computer. The computer software then enables the scientist to sort these light-interrupting events by particle size. The third instrument is a video plankton recorder (VPR), which may take as many as 30,000 photo frames per sample. The resulting images help to give researchers a visual confirmation as to the various life forms inhabiting the water column.

After each instrument has been checked and is in sync with its perspective computer the vertical profiling package is lowered from the deck via a motorized cable. The instruments are lowered to within a meter of the seafloor and then are immediately lifted back to the surface. During the down-and-back journey all points of data collected by the 3 instruments are loaded onto three computers for later analysis.

Researchers hope that by sampling the water column they can gain a better understanding of the biotic and abiotic factors that affect copepods and their distributions. Copepods are of particular interest as they are a primary food source for a multitude of marine animals from fish fry to whales.