Michelle Greene: Visual Sighting Team, July 23, 2018


NOAA Teacher at Sea

Michelle Greene

Aboard NOAA Ship Gordon Gunter

July 19 – August 3, 2018

 

Mission: Cetacean Survey

Geographic Area: Northeast U.S. Atlantic Coast

Date: July 22-23, 2018

Latitude: 40° 35.213″ N

Longitude: 66° 6.692″ W

Sea Surface Temperature: 23.4° C (74.1° F)

Knots: 7.85 knots

Science and Technology Blog:

The visual sighting team started early this morning at 6:00 am and had rotating shifts of 30 minutes each until 7:00 pm.  The different shifts included watching with regular binoculars on the port and starboard sides, watching with the big eyes on the port and starboard sides, and being the data recorder for sightings.  I had the opportunity to shadow scientists in each of these positions throughout the first day and actually performed the duties on the second day.

Members of the Cetacean Survey Visual Team on Lookout

Members of the Cetacean Survey Visual Team on Lookout

One of the important jobs the data recorder has is to input the environmental conditions at a certain point in time.  The first measurement to input is the percent of cloud cover which is just a number from 0 to 100. Then the glare magnitude is determined on an ordinal scale from 0 to 4 with a value of zero meaning none and a value of four meaning severe.  After determining the glare magnitude, the percent of glare cover is determined.  Since the two sets of big eyes cover from 90 degrees left of the bow to 90 degrees right of the bow, the glare covering this spaced is what is determined.  The data recorder also has to determine the degree angle and height of the ocean swell.  Swell is not the wind waves generated by local weather.  It is the wind waves that are generated by distant weather systems.  Then the Beaufort scale is used to determine the amount of wind on the ocean.  The scale was developed by Sir Francis Beaufort of the United Kingdom Royal Navy in 1805.  The scale ranges from 0-12.  A zero score means the surface is smooth and mirror like, while a score of 12 means there are hurricane force winds.  Rain or fog is also determined by the data recorder.  Finally, the data recorder has to determine a subjective condition of the weather overall.  This is on an ordinal scale from 1 to 4 with 1 being poor and 4 being excellent.

When a marine animal is sighted by one of the observers, the data recorder has to input several measurements about the event.  The bearing of the location of the animal has to be determined using the big eyes.  Also, the big eyes have a scale in the lens called reticles that determines distance from the ship to the animal.  A conversion scale can then be used to determine how far away the animal is in meters or nautical miles.  The number of animals sighted, including any calves that are in the group, has to be given.  The group’s swim direction has to be determined based on bearing from the ship.  If possible, the species of the group has to be given.  Since the objective of this survey is to find the occurrence of Mesoplodons in the North Atlantic Ocean, determining the species is very important.  Also the observer has to give the initial cue as to what determined the identification of the species.  Several different cues are available such as the body of the animal, the blow of a whale or dolphin, or the splash.

The software used to input the occurrence of a marine mammal automatically inputs the GPS of a sighting.  The initial route for this survey is a zig zag pattern out of Rhode Island towards Georges Bank.  There are several canyons with very deep waters (over 1,000 meters) which is where the Mesoplodons make foraging dives to get food.  Instead of making a straight line through the canyons and only making one pass through the area, using zig zag routes gives the survey a better chance of locating Mesoplodons.  The chief scientist uses the information from sightings to track a path for the ship to take the next day.  Sometimes the acoustics team hears possible Mesoplodons.  If the acoustics team can find a convergence of the area of an animal, they will tell the ship to go at a slower rate or turn.

The map here shows the sightings of Mesoplodons from the beginning of our journey and the zig zag pattern taken by the chief scientist.  The first day of our journey, a storm was coming up the East Coast.  The Gordon Gunter‘s Commanding Officer (CO) determined that we could run from the storm by going east in a straight line direction instead of doing the zig zag motion.  The CO was correct, because we did not have bad weather.  The ocean had a lot of high swells which made the boat rock tremendously at times but no rain.

GU18-03_Map_24July2018_wLegend

A map of the daily route of the Gordon Gunter based on sightings.

 

Personal Log

I have found my favorite place to be on the visual sighting team…being the data recorder.  Statistics is my passion, and being the data recorder puts me in the middle of the action getting mass amounts of data.  It also helps that the data recorder sits in a high chair and can see a wide area of the ocean.  The scientists have been very helpful in finding me a milk crate, because that chair is so high I cannot get onto it without the milk crate.  Being the data recorder can be intense sometimes, because multiple sightings can be made at the same time.  In any free time I have, I will fill in as the data recorder.  It is lots of fun!

Data Recorder

Favorite place to be on the visual team – Data Recorder

One thing that was a little intimidating to me at first was the intercom system.  I would hear things like, “Fly Bridge Bridge.”  Then the data recorder would say “Bridge Fly Bridge.”  I had no clue of what they were talking about.  Then all of a sudden it made sense to me.  In “Fly Bridge Bridge,” someone from the Bridge is calling up to us on the Fly Bridge.  The Bridge has a question or wants to tell the people on the Fly Bridge something.  Since I figured it out, I am ready to go.

I have learned so much on this cruise in the short time I have been aboard the Gordon Gunter.  My head is exploding with the numbers of lessons that I can incorporate into my statistics classes.  I have also talked with the acousticians, Jenny, Joy, Emily, and Anna Maria, and have come up with lessons that I can use with my algebra and calculus classes as well.  The scientists have been very generous in sharing their knowledge with a science newbie.  Being a math teacher, I want to be able to expose my students to all kinds of content that do not deal with just the boring math class.  Being a Teacher at Sea has opened up a whole new experience for me and my students.

We have an interesting participant in our cruise that I was not expecting but was happy to meet…a seabird observer.  Before this cruise I did not know there were birds that pretty much lived on the surface of the ocean.  These birds have been flying around the ship which is about 100 nautical miles from shore.  The seabird observer documents all sightings of seabirds and takes pictures to include in his documentation.

Did You Know?

Reticles are the way a pair of binoculars helps observers to determine the distance to an animal; however, the conversion from reticles to distance is not an instantaneous solution.  Based on the height of a pair of binoculars on the ship, reticles can mean different distances.  A conversion chart must be used to determine actual distance.

Check out this article on how to estimate distance to an object with reticles in a pair of binoculars:

https://www.osc.co.uk/estimate-range-with-reticle-binoculars-2/

Animals Seen

  1. Sperm whales (Physeter macrocephalus)
  2. Fin whales (Balaenoptera physalus)
  3. Cuvier’s beaked whale (Ziphius cavirostris)
  4. Risso’s dolphins (Grampus griseus)
  5. Bottlenose dolphins (Tursiops truncatus)
  6. Common dolphin (Delphinus delphis)
  7. Great shearwater bird (Puffinus gravis)
  8. Cory’s shearwater bird (Calonectris borealis)
  9. Wilson’s storm petrel bird (Oceanites oceanicus)
  10. Leach’s storm petrel bird (Oceanodroma leucorhoa)
  11. White-faced storm petrel bird (Pelagodroma marina)
  12. Red-billed tropicbird (Phaethon aethereus)

Vocabulary

  1. acoustician – someone whose work deals with the properties of sound
  2. bearing – the direction from your location to an object in the distance starting at 0° which is located at absolute north.  For example, if an animal is spotted at 90°, then it is due east of your location.
  3. blow of a whale – the exhalation of the breath of a whale that usually looks like a spray of water and is an identifying feature of different species of whales
  4. bow of a ship – the point of the ship that is most forward as the ship is sailing (also known as the front of the ship)
  5. cloud cover – the portion of the sky that is covered with clouds
  6. foraging dive – a type of deep dive where a whale searches for food on the ocean floor
  7. glare – the light reflected from the sun off of the ocean
  8. nautical mile – a measurement for determining distance on the ocean which is approximately 2025 yards (or 1.15 miles) or 1852 meters
  9. port side of a ship – when looking forward toward the bow of the ship, the left side of the ship is port
  10. starboard side of a ship – when looking forward toward the bow of the ship, the right side is starboard

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