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: August 2, 2005
Weather Data from the bridge
Latitude: 42° 5’ N
Longitude: 67° 28’ W
Visibility: undetermined
Wind direction: E ( 107 degrees)
Wind speed: 12 knots
Sea wave height: 3’
Swell wave height: 0’
Sea water temperature: 14°C
Sea level pressure: 1022.2 millibars
Cloud cover: 30% Partly cloudy,cumulus
Questions of the Day: Explain what might happen if the sea scallop population were to change drastically. What other organisms are in the same community as the scallop?
(You may want to look at the Day 8 food web and the graph below.)
Yesterday’s Answer:
Scallops are predators because they eat something else, that is phytoplankton and zooplankton. They are primarily herbivores. Scallops are mostly prey to, or eaten by, sea stars and crabs.
Science and Technology Log
*CTD = Conductivity, Temperature, Depth instrument is used to measure salinity, temperature, and depth at selected stations. This is important because different species of marine animals (including the sea scallop) have tolerances for certain temperatures and depths.
On Tuesday, the ALBATROSS IV continued surveying the northern edge of Georges Bank as it makes its way west toward Woods Hole. The weather has been very cooperative with a ridge of high pressure overhead, despite the routine early dense fog. Scallop counts are very low while other newer species are being observed, including various species of sea stars and the hagfish. The chart below shows a selected number of species and the stations in which they were found.
Sea Scallop Survey Leg II: Stations Where Species Were Found
Questions:
1) Which of these species was caught at the most stations?
2) Which of these species was caught at the least number of stations?
3) At how many more stations were the sea scallops caught than the red hake?
4) What might explain why sea scallops were found at the most number of stations on this survey?
5) What is the difference between the number of stations that the yellow tail flounder were located and the sea scallop?
Personal Log
Measuring Up
Ten minutes to go before it’s time for another CTD,
When the crew will set and drop it down into the waiting sea.
It only takes a moment for the thing to take a dash,
To the bottom it will go, but watch that it don’t crash.
Then it’s time to drop the dredge and ready for the tow,
Soon you’ll hear them haul it in, and it’ll be time to go.
