Tag: shark survey

NOAA Teacher at Sea Kimberly Lewis
NOAA Ship: Oregon II
July 1 -July  16 2010

Mission: SEAMAP Summer Groundfish Survey
Geographical Area of Cruise: Gulf of Mexico
Date: Sunday, July 5, 2010

Weather Data from the Bridge 
Time: 1000 hours (10:00am)
Position: Latitude = 27.58.38 N; Longitude = 096.17.53 W
Present Weather: partly cloudy, haze on the horizon
Visibility: 8-10 nautical miles
Wind Speed: 17 knots
Wave Height: 2-4 feet
Sea Water Temp: 28.6 C
Air Temperature: Dry bulb = 29.2 degrees Celsius; Wet bulb = 26.1 C
Barometric Pressure: 1011.1 mb

Science and Technology Log

The purpose of the SEAMAP Summer Groundfish Survey is to collect data for managing commercial fisheries in the Gulf of Mexico. SEAMAP stands for Southeast Area Monitoring and Assessment Program.

Right now we’re working along the Gulf Coast of Texas, far from the BP Deepwater Horizon oil spill, so we’re not seeing any effects of oil here. However, part of our mission is to collect fish for testing to make sure that oil spill has not impacted the marine life in this area and that the fish and shrimp from Texas are safe to eat. We’re also collecting water samples from this area to use as baseline data for the long-term monitoring of the impact of the oil spill in Gulf.

There are four main ways the Oregon II is gathering SEAMAP data on this cruise, and we’ve already learned how to use all of them. The main way we collect data is by trawling, and this is where we do most of our work on the Oregon II. In trawling, we drag a 42’ net along the bottom for 30 minutes, haul it up, and weigh the catch. We then sort the haul which involves pulling out all of the shrimp and red snapper, which are the most commercially important species, and taking random samples of the rest. Then we count each species in the sample and record weights and measurements in a computer database called FSCS (Fisheries Scientific Computer System).

Here on the Texas coast, where we’re working now, the SEAMAP data is used to protect the shrimp population and make sure that it’s sustained into the future. Since 1959, Texas has been closing the shrimp fishery seasonally to allow the population to reproduce and grow. The SEAMAP data allows Texas to determine the length of the season and size limits for each species. Judging by our trawls, the Texas shrimp population is healthy.

Another method of data collection is the CTD, which stands for Conductivity, Temperature, and Depth. The CTD takes measurements from the surface to the bottom, creating a CTD profile of the water column at our trawling locations. These data are important to assess the extent of the hypoxic “dead zone” in the Gulf of Mexico, and to relate the characteristics of our trawling hauls to DO levels. SEAMAP data collected since the early 1980s show that the zone of hypoxia in the Gulf has been spreading, causing populations to decline in hypoxic areas.

We also use Bongos and Neustons to gather data on larval fish, especially Bluefin Tuna, Mackerel, Gray Triggerfish, and Red Snapper. The Neuston is a rectangular net that we drag along the surface for ten minutes to collect surface-dwelling larval fish that inhabit Sargassum, a type of seaweed that floats at the surface and provides critical habitat for small fish and other organisms. We drag the Bongos below the surface to collect ichthyoplankton, which are the tiny larvae of fish just after they hatch. The Neuston and Bongo data on fish larvae are used for long-term planning to maintain these important food species and keep fish stocks healthy.

Personal Log

Day 1: docked
Day 2: we left the port in Galveston (July 2). My shift started immediately but by the time we actually left port and reached the first station my shift was over 1200 noon. So far so good!

Day 3: 2400 hrs or Day 4: 00:00 hrs.
– the sea sickness is getting me a little now. The rough seas are most likely the main culprit, however, I have not been out to sea for this period of time before. Once the seas calm down I should have a better idea. I do know this, my shift leader Alonzo and the chief scientist Andre have both been very understanding of my adjustment to sea life. The entire staff on board for that matter are very understanding and concerned for everyone’s well being.
– This was my first full shift. We are BUSY aboard the Oregon II ! A catch will come in for processing, which I will explain processing on my next blog, and we sometimes are still processing the last batch or we are up front taking CTD samples and bringing in our bongos/neustrons. I have learned a lot of things in a short period of time.

July 4, 2010 – Lots of stations (places where we deploy our nets) tonight. We actually got a little backed up. There are five people on my shift and it takes all 5 of us working non-stop to get the job done.

July 5, 2010 – I am feeling better today, so much that I uploaded my blog! I keep waking up at 5pm and unable to go back to sleep, but I am going to try now to catch a couple more hours as my shifts starts again in 3 hours.