NOAA Teacher at Sea
Aboard NOAA Ship Oregon II
September 3 – 15, 2017
Mission: Snapper/Longline Shark Survey
Geographic Area of Cruise: Gulf of Mexico
Date: September 5, 2017
Weather Data from the Bridge (get data from bridge)
Latitude: 29 degree 36.0 N
Longitude: 86 degree 10.1 W
Sea wave height: < 1
Wind Speed: 7 kts
Wind Direction: 185
Visibility: 10 nm
Barometric Pressure: 1016.3
Science and Technology Log
The Oregon II has two sets of crew – the ship’s crew headed by Captain Dave Nelson and the science crew headed by Lisa Jones. Captain Dave and Lisa work closely together making decisions that impact the survey. The ship’s crew keeps us afloat, fed and ultimately determines where we go based on weather. The science crew, well you guessed it, is focused on the science and collected data at predetermined sampling sites.
This post will look at some of the science happening on board. On board are four NOAA scientists as well as other volunteers and researchers that are helping with this survey. NOAA’s focus on this survey is all about sharks and snapper. We are collecting data on what we haul up from the longlines as well as abiotic factors including temperature, depth of line, dissolved oxygen, and salinity of the water. The data is entered into a computer and becomes part of a larger data set.
Two researchers on board working as volunteers are Brett Warren and Carlos Ruiz. They are parasitologists meaning they study parasites that sharks and other organisms carry. A parasite is an organism that lives off other organisms (a host) in order to survive. They are finding all sorts of worms and copepods embedded in the nose, gills and hearts of fish and sharks. These two spend much of their time using microscopes to look at tissue samples collected.
In speaking with Brett, the life cycle of parasite can be simple or complex. The simple direct life cycle is when the parasite spends its entire life on the host organism. A complex indirect life cycle for a parasite is when the parasite reproduce, the young hatch and swim to an intermediary host, usually a snail, mollusk or polychaete. This is where it gets really cool, according to Brett. It’s the intermediate host where the parasites asexually reproduce by cloning themselves. Next, the parasite leaves the intermediate host and swim to their final host and the process starts all over again. From a parasite perspective, you can see how difficult it would be for an indirect life cycle to be completed, because all the conditions need to be right. Brett is studying flatworms that have complex lifecycles and Carlos is studying copepods that have direct life cycles.
Their main focus on this survey is to discover new species of parasites and understand the host- parasite relationship.
The past few days have been slow with only a few stations a shift. We have hauled up some sharks, eels and even a sharksucker fish. One station had nothing on the 100 hooks set! Talk about getting skunked. As we move west I am hoping we get to see more sharks as well as more variety. Other wildlife spotted include dolphins, jellyfish and birds.
Did You Know?
Just because it’s a parasite doesn’t mean it harms the host. Some just live off of another organism without harming it.
Question of the day:
What are the two types of life cycles a parasite can have? (hint: read the blog)