Tag: plankton

NOAA Teacher at Sea
John Sammons
Onboard NOAA Ship Albatross IV
July 25 – August 4, 2005

Mission: Ecosystem Survey
Geographic Region: Northeast U.S.
Date: July 28, 2005

Weather Data from the Bridge

Latitude: 40° 58’ N
Longitude: 67° 13’ W
Visibility: undetermined
Wind direction: SSW (217 degrees)
Wind speed:  11 knots
Sea wave height: 0.4’
Swell wave height: 1.4’
Sea water temperature: 18°C
Sea level pressure: 1013.3 millibars
Cloud cover: Obscure, Fog, Haze, Dust

Question of the Day: In which direction is the ALBATROSS IV relative to Virginia (north, south, east, west, northeast, northwest, southeast, southwest)?  Use the latitude and longitude points in today’s log or refer to the “Location” link shown on the webpage.

Yesterday’s Answer: Some scallops use camouflage and countershading to help protect themselves from their predators by blending into the ocean bottom (light to dark brown as seen from above) and blending into the sky (white as seen from below). Because there are two different colors, this is called countershading, which is a form of camouflage and is a physical adaptation.

Science and Technology Log

Proper navigation is an important component of the ALBATROSS IV’s ability to correctly manage the station locations. Without it, the ship would be lost, and there would be no way to accurately measure station samples over time. First, an electronic course map is generated that has the predetermined route and survey station. Course adjustments are made as the ship approaches a station so that it passes within one mile of the station and over it on its way to the next station. Since the dredge stays in the water for fifteen minutes, it requires accurate course and ship positioning. Second, RADAR is used to keep track of other ship traffic. Radios and an automated tracking system are used to keep a safe distance from other ships like freighters and container ships. Third, visual observations from the bridge enable the watch person to determine visibility and weather conditions that may effect navigating the ship. Of course, when there is dense fog like the ship has experienced on the present cruise, the other two components become critical. While it may seem like a glorious job to be up on the bridge of the ship, it certainly requires a person who is able to perform several operations at once and take the blame for things that go wrong.

Thursday has been spent sorting and sampling the catch, which has included flounder (flat and slimy), goosefish (mean and toothy), hake (slender and colorful), crab (determined and crusty), skate (mysterious and smooth) and of course, scallops (graceful and tough). As we sample each station’s catch, we have to check over a list provided by land-based scientists in order to save what they need for their research. Two of those scientists are traveling with us and are very knowledgeable about scallops. Dvora Hart is quantifying the abundance of calico scallops, aging sea scallops, and assessing meat quality in certain areas. Avis Sosa is making a reference collection of shells commonly caught during the clam and scallop surveys, including clappers. Clappers are scallops that are still hinged or connected, but contain no internal organs.

The seas at 40°N and 66°W are affected by Tropical Storm Franklin in the distance. The swells are estimated to be 8 – 10 feet and are rocking the boat constantly. It is difficult to walk straight or stand still, but it is still safe to be here.

You have to also make sure everything is attached, or it will slide right unto the floor.

Personal Log

Sort, Sort, Sort 

Time to muster and be alert for another shift begins,
Shells and starfish wait for us, along with things with fins.
Pull up a bucket and a pad to sample and to sort,
It’s been three days since ALBATROSS steamed from the distant port.
Ouch! I bellowed as a scallop clamped onto my finger,
Upon the deck you sort and scoop, no time to stand and linger.

NOAA Teacher at Sea
John Sammons
Onboard NOAA Ship Albatross IV
July 25 – August 4, 2005

Mission: Ecosystem Survey
Geographic Region: Northeast U.S.
Date: July 27, 2005

Weather Data from the Bridge

Latitude: 40° 31’ N Longitude: 68° 49’ W
Visibility: undetermined
Wind direction: SSW
Wind speed: 16 knots
Sea wave height: 0
Swell wave height: 0
Sea water temperature: 18°C
Sea level pressure: 1012.6 millibars
Cloud cover: Clear

Question of the Day: How do scallops use camouflage and countershading to help protect themselves from their predators? (See pictures 5 and 6.) Is this a physical or behavioral adaptation?

Yesterday’s Answer:

1. pulley         2. inclined plane   3. lever
4. pulley         5. pulley                6. inclined plane
7. lever           8. pulley                9. wheel and axle.
Answers will vary on the second part of the question.

Science and Technology Log

The purpose of this scallop survey is to study the “basic biology and distribution of “ scallops and to study the “population dynamics of the species.” Historically, scallop populations have increased and decreased at alarming rates. Overfishing and natural predators have lead to a significant decline of scallops in the Atlantic Ocean. Conversely, scallop populations have flourished in areas that are closed to fishing, thus allowing scallops to mature more. While this is by far the most important reason why there are fewer scallops, scallops have natural adaptations that also help them survive.

One structural adaptation is their color. Notice in the pictures above that some scallops are dark on top and lighter on the bottom. This allows the scallop to blend into the sandy bottom as seen from above and the bright surface as seen from below. A behavioral adaptation that the scallop has is to shoot water as a way to propel itself from a predator. However, these adaptations are not always strong enough to protect themselves from predators and humans.

On Wednesday, we continued to collect scallops. The shells will be used for determining the age of the scallops. In addition, the meat and gonad weights will be used to estimate shell height/meat weight relationships and annual mating cycles. Some other sea life that is coming up in the dredge are different species of flounder, hake, crabs, skate, goosefish, hermit crabs, and starfish. There are many knowledgeable people on board who have provided mini-lessons for me on fish identification, scallop shucking, data entry, and population dynamics.

Personal Log

Sleepless on the Atlantic 

Steaming forward to the station that is just right up ahead,
Six hours is up, and our shift will end, so it is time to go to bed.
Before I rest and take a nap, some chow I would like to eat,
It will be good to rest a little while and get off of my feet.
The food is great, so many choices that we are able to choose,
Just fill ‘er up and head to bed and settle for a snooze. 

NOAA Teacher at Sea
John Sammons
Onboard NOAA Ship Albatross IV
July 25 – August 4, 2005

Mission: Ecosystem Survey
Geographic Region: Northeast U.S.
Date: July 26, 2005

Weather Data from the bridge

Latitude: 40.31 N
Longitude:  69.05 W
Visibility: unknown
Wind direction: S (193 degrees)
Wind speed: 19.6 knots
Sea wave height: 1’
Swell wave height: 1’
Sea water temperature: 17.7°C
Sea level pressure: 1013.0 millibars
Cloud cover: 00 Clear

Question of the Day: Identify and classify the simple machines that make up machines found around the ship. Match the pictures above with the six simple machines-inclined plane, wedge, wheel and axle, screw, wedge, and pulley. Choose one of the machines shown in the pictures, and explain how it makes work easier to do. (Send your answer to one of the e-mails listed below.)

Yesterday’s Answer: The weather instruments located on the ALBATROSS IV that measure wind speed and direction are the anemometer and wind vane. They are combined into one instrument, and it looks like an airplane without wings.

Science and Technology Log

Machines serve an important job on the ALBATROSS IV and any other ship. The six simple machines in of themselves can make work easier to do. For example, a round doorknob handle on a ship’s door is not as common as a lever handle. On a ship, you are often unable to turn a doorknob because your hands may be wet or you may be carrying something. Also, door levers make it easier to tighten hatches securely. Some of these simple machines are combined to make compound machines. On the ship, you will find many examples of both simple and compound machines, all of which make work easier and safer to do.

One way in which machines make the scallop survey easier and safer is the use of a crane with many pulleys. The eight-foot wide dredge is lowered as the ship slows to 3.8 knots. When the dredge reaches the bottom, it is towed for 15 minutes. This allows the dredge to drag and fill the netted and chained device. This device resembles a large purse overfilled with goodies when full. Then the catch or load is dropped and released onto the deck. The large pulley system on one of the cranes allows for a cable that can handle a large weight. Likewise, the boom of the crane supports the weight of the towing dredge. One improvement that would help this compound machine would be to create some kind of conveyor system to bring the load back toward the sampling and measuring area without having to drag loaded baskets and buckets. Coincidentally, this is part of the design of the new ship that will replace the ALBATROSS IV, and as a result make work even easier.

Here is a graph showing the total number of scallops brought in at each of the stations so far. Some areas in which the tow was made are closed to scallop harvesting. As a result, larger and more developed scallops were caught. In tomorrow’s log, you will learn a little more about scallop adaptations that have helped them survive despite negative human influences.

Personal Log

Sea Duty 

The waves come toward the ALBATROSS and into the lengthy side,
Feel the rocking back and forth, so hold on for the bumpy ride.
Prepare the dredge and send it forth to bring up another load,
Bring out the baskets and buckets and pads to get in a sorting mode.
Place the containers on the scale then measure the scallop’s shell,
Soon the shift will come to an end with only stories left to tell.