Bill Henske, Mind if We Drop in? June 19, 2015

NOAA Teacher at Sea
Bill Henske
Aboard NOAA Ship Nancy Foster
June 14 – 29, 2015

Mission: Drop camera operations
Geographical Area: Florida Keys and Dry Tortugas

Date: Friday, June 19, 2015

Weather Data from the Bridge: East wind 10-15 kts.  Seas 3-4 ft (2 ft inside reef).  Isolated showers and thunderstorms

Science and Technology Log

Drop Camera Operations

We have so many ways to see our planet using scientific tools.  The Nancy Foster, for example, uses radar to see boats and weather in the direct vicinity.  The ship uses satellite images to prepare for missions and to support surface information. Onboard, the Nancy Foster uses sonar to measure ocean depths and detect the undersea activity of marine organisms, and map the physical characteristics of the seafloor.

The ship collects hydrographic information by making repeated passes over  an area of interest.  This is the product.
The ship collects hydrographic information by making repeated passes over an area of interest. This is the product.

This technology all relies on our acceptance that a pixel of light with a specific value equals some tangible unit of mass or energy in our ocean.  The equations and processes that help us determine the relationship between the data collected and what is meaningful to us must be worked out through careful analysis and study.  In our case, we are trying to work out the relationship between certain patterns of sonar feedback and what habitat is present on the seafloor.

Don Checking Drop Camera Setup before lowering down into Warsaw Hole.
Don Checking Drop Camera Setup before lowering down into Warsaw Hole.

Don Field of NOAA’s National Center for Coastal Ocean Science calls himself a pixel-pusher.  Deciphering the images and data that show up on a monitor means having an astute understanding of what each bit of data means.  Part of Don’s research involves squeezing more data from the bits collected by looking for associations between these bits of light and the real world.  Identifying the relationship between these sonar profiles and the habitat on the seafloor means matching up pixels from a screen with what exists in the actual environment.  If we can reliably identify seafloor type by sonar, for example, we could begin to quantify habitat for individual species rather than relying on approximations.

Me pushing pixels on one of the sonars. I can't get it to work though. (Scott Donohue, NOAA)
Me pushing pixels on one of the sonars. I can’t get it to work though. (Scott Donahue, NOAA)

Don calls this ground-truthing.  This means a researcher on the ground (or in the ocean in our case) must connect the features from satellite and sonar with images and data collected from onsite.  Our project on this mission involves deploying a drop camera from one of our small vessels and determining what is there.  Several coordinates are chosen from sonar and satellite pictures.  These coordinates are entered into the GPS of the small dive boats allowing us to pinpoint the exact location within just a few meters.

The drop camera is a fairly self descriptive term.  This is a specially designed black and white camera that is deployed from the side of the small vessel.  The camera is mounted within a protective cage with weights attached to facilitate its trip to the bottom.  While the turbidity of the water is very low, light is still limited at deeper depths.  The camera has lights that enable viewing in low light or during nocturnal missions.  The reason we use a black and white camera is that they can operate in much lower light levels than color cameras.  Think about your own color vision and how it diminishes as the sun goes down.

This is our drop camera.  The two brass devices attached to the left are for lasers which allow the operator to determine depth as well as relative size of objects in the field of view.
This is our drop camera. The two brass devices attached to the left are for lasers which allow the operator to determine depth as well as relative size of objects in the field of view.

The camera rig is tethered to the GPS and video recorder with a 300 foot long coaxial cable.   This cable is specially designed for this application with corrosion resistant terminals and kevlar sheathing along the entire length.  We also attached a downrigger to the camera apparatus to reduce the wear and tear on the cable and to speed retrieval of the unit.

On board, we monitor the camera as it is lowered almost to the sea floor at each chosen coordinate.  Our equipment records and geotags the video with the exact location so it can be aligned with mapping data back in the lab.

The controls of the drop camera.
The controls of the drop camera.

On the drop camera, we also utilize a fairly “off the shelf” GoPro camera.  This camera doesn’t feed information back up to the vessel and isn’t connected to GPS but it can provide other useful information about the species encountered along the trip down.  This biological information can be used for other projects and adds to the overall value of the mission.

One of the critical things for all field scientists is to check the functioning of gear before heading out. Don and I set everything up in the drylab and on deck.  There were several bugs to work out of the procedures before heading out to our first coordinates.  Once we addressed the issues we had with the equipment, our dropcam was ready to go.

Heading out to Warsaw Hole with our drop camera and equipment..
Heading out to Warsaw Hole with our drop camera and equipment.

We headed out to the locally famous Warsaw Hole.  This spot is known for spawning populations of several important fish.  We wanted to determine if the seafloor with in this structure held any clues to why it was so important to fish.  At over 300 feet deep, this area is not conducive to exploratory dives.  This inaccessibility made it a good candidate for our mission.

After heading out to the coordinates we unpacked the camera, GPS, and computers.  There was a sudden loss of power to the camera.  A little trouble-shooting and we determined it was the fuse.  Saltwater is tough on electronic components!   A blown fuse was not one of the things we prepared for the day before.  We radioed the ship with our fuse requirements and after a short shuttle back to the Nancy Foster, we were back in business.

What could be in the mysterious Warsaw Hole?  At 100 feet deeper than the surrounding seafloor, what was it about this place that encourages aggregations of the Warsaw grouper (Epinephelus nigritus)?  As the camera was lowered deeper, we were able to see everything in the water column as it swam to one side or the other.

We reached our destination depth and discovered that Warsaw Hole is a plain, ordinary sandy bottom.  In the world of science this unexceptional discovery is called “zero data”, but it is valuable information nonetheless, as we try to characterize all of the habitats in the area.

Personal Log

The Dry Tortugas is one of the most out-of-the-way National Parks in the US.  This former Civil War era fort and the surrounding small keys are a paradise of colorful fish and raucous colonies of seabirds.  While the camp site was busy, it was definitely not crowded after the Key West ferry had gone home for the day.  If you decide to spend the day or camp over night, bring water.  It is named for the fact that there is no fresh water!

We were able to snorkel almost entirely around the fort.  The submerged walls of the old fort are encrusted with corals, sea fans, annelids, and sponges of every shape and color.  The remnants of former building materials are almost unrecognizable as human detritus, instead housing a great diversity of interesting reef organisms.

Unfortunately, we did not see the infamous crocodile.  Tick Tock.

Here it is official as I stand in front of the Dry Tortugas National Park Sign.
Here it is official as I stand in front of the Fort Jefferson – Dry Tortugas National Park Sign.

By the Numbers

  • Sea Turtles – 1
  • Square miles of seafloor surveyed – 21.02
  • Treadmill Miles – 6.25
  • Drop cam dives – 6
  • Teacher at Sea Hat Recoveries – 2

 

Amy Orchard: Day 4, 5 & 6 – Tagging, Gumby suit, Lion Fish Dish and Fort Jefferson, September 19, 2014

NOAA Teacher At Sea
Amy Orchard
Aboard NOAA Ship Nancy Foster
September 14 – 27, 2014

Mission: Fish Tagging
Geographical area of cruise: Tortugas Ecological Reserve North & South sections: Tortugas Bank
Date: September 17, 18, 19, 2014

Weather, September 19, 2014 20:00 hours
Latitude 24° 35’ 07’’N Longitude 83° 01’ 09’’W
Broken clouds, clear.
Humidity 10%.
Wind speed 7 knots.
Air Temperature: 29° Celsius (84° Fahrenheit)
Sea Water Temperature: 30.2° Celsius (86.7°Fahrenheit)

CLICKING ON THE SMALL PHOTOS WILL ENLARGE THEM & REVEAL HIDDEN TEXT.

WEDNESDAY:

Resetting Traps

We did not have great success with the shrimp bait.  Guess these fish prefer their shrimp au naturel where as we gave them cooked, peeled and deveined shrimp.  This morning we set out again in the small boats so the divers could re-bait the traps with squid instead.

Ariel the Scientist
Finally Ariel looks much more like a scientist now that she has a pen in her pocket!

Safety on the ship

Safety always comes first on the Nancy Foster.  We have had briefings on safety, we wear hard hats while the cranes are moving, we wear closed toe shoes (except when in the shower) and we have had fire drills & first aid emergency drills.  Today we had an abandon ship drill.  First we each arrived at our muster stations (our assigned place to meet), then we climbed into our Survival Suits (nicknamed the Gumby suit.)  This is made of very thick neoprene, probably 7-9 millimeters thick, and covers you from head to toe to fingertips.  It is meant to keep you safe from hypothermia if you were overboard for a long period of time.

After wriggling back out, we went to find our assigned life raft.  There are 6 rafts which each hold 25 people.  There is enough bunk space on the ship for 37 people, so there are plenty of life rafts for all.  Three rafts sit on each side of the ship so even if the ship was under water listing to one side, we could still access enough rafts for all.

In addition to the Survival Suit, Nick thought he would be safer being more visible so he wore a few extra items to ensure his safety!

Nick fuzzy hat w/ bow & cool googles
Nick has a horde of awesome hats. Keep your eyes peeled for more.

Dancing with the Remotely Operated Vehicle

Part of each day has been spent looking underwater with the Remotely Operated Vehicle piloted by Lance Horn and Jason White from the University of North Carolina at Wilmington (yet another partner in this 14-day collaboration)

ROV pilots
Lance Horn and Jason White are geniuses with the Remotely Operated Vehicle. There are lots of very highly technical parts to this equipment and they do it all – and they do it well.

I will be sharing lots more information about the ROV in an upcoming post.  Today I wanted you to see who else besides scientists are curious about the ROV (the large instrument with the yellow top you see in the video here)

THURSDAY:

Fish Surgery

We checked traps again this morning and had success with the squid.  The dive teams will perform surgery today!  The surgery only takes about 10 minutes, which may seem quick, but since they are underwater at a depth of about 100 feet, they must work quickly so as to not run out of their air supply.  One scientist (usually Paul Barbera, FWC Associate Scientist – who they call the Fish Whisperer) will hold the fish steady while another will make the incision, insert the acoustic transmitter and then stitch up the incision. The stitches will dissolve in about a week or two.  The acoustic transmitter (fish tag) will last 2-5 years.  Life span of the tag is determined by it’s battery life.  The smaller tags (for smaller fish) can last 2 years and the larger tags (for larger fish) will work for about 5 years.  This allows the scientists to gather information on the same fish for multiple years, giving them a really good idea of their seasonality – or the fish’s movements between different areas, both protected an unprotected.

fish tags
Acoustic Transmitters – Fish Tags which will be surgically placed in the fish at a depth of about 100 feet. Here you can see the smaller ones are about 4 cm and the larger 6.5 cm

This footage was not shot during our cruise, but Ben Binder, FWC Biological Scientist, shared this video with me describing the surgery process.  Here you will see two scientists who are aboard the Nancy Foster with me.  Paul is securing the fish and Mike McCallister, FWC Biological Scientist, is performing the surgery.  They are working with a Lion Fish here.

Placing the fish tag is just one part of the process of collecting the data the scientists are hoping to gather.  The second part is to place an instrument which can read the acoustic transmitter as it swims past (within the fish of course!)  Danielle Morley, FWC Assistant Research Scientist, and I worked to prepare some previously used acoustic receivers.  Each of the 90 receivers the FWC have placed in the waters off the Florida Keys costs about $2500.  Therefore, used receivers are reprogrammed, repainted with anti-fouling paint and used again.  Anti-fouling paint makes it very difficult for animals like barnacles to build their calcium carbonate skeletons on the receiver’s exposed top.  The receivers are made up of a hydrophone, a circuit board and a battery.  I replaced the batteries and cleaned up the O rings.  The O rings are extremely important as they ensure the capsule is completely water-proof and can be submerged in ocean water for a year at a time.

After a year, the batteries need replaced and the data needs retrieved.  Today, the divers will retrieve 6 acoustic receivers on Riley’s Hump and replace them with those we reprogrammed.  This is footage of our divers (Jeff, Sean and Colin) making the swap.  Thanks to Cammy Clark, the Miami Herald reporter, who dived down about 100 feet to capture the action.

FRIDAY:

Trap Retrieval

Over the last 5 days, there have been 65 dives and 3 surgeries performed.  The scientists deem this as very successful trip.  Additionally, all divers returned safely to the ship after each dive!  This morning the divers are retrieving the traps, which like the receiver stands are allowed by a special permit from the FKNMS.  Even if conditions did not allow us to get the traps and they needed to stay at the bottom, no fish would be caught for very long.  Each trap is closed with a zinc clip that will dissolve after a week or two.

Zinc Clips
Zinc clips keep the traps closed, but only temporarily. They dissolve after a week or two allowing any fish to escape if a trap has to be abandoned due to weather or other conditions.

The large fish we are trapping can easily stay down in a trap that long.  But today, the weather allowed us to retrieve the traps.

Along with the traps, Ben and Ariel brought five Lion Fish Pterois volitans back up.

 

Lion Fish are not naturally found here.  They are native to the Indo-Pacific.  It has not been determined exactly how they got to the area but they are very popular for home aquariums.  However, since they are voracious predators, after eating all their other aquarium fish, people have been dumping them in the Atlantic Ocean for decades.  It was decided that efforts to eradicate the species would be futile since they are prolific breeders, have no natural predators and have been found in extremely deep waters where it would be unfeasible to reach them.  Instead, there are large efforts to manage their populations in certain areas.

One does need to be extremely careful as they have venomous spines – 13 along the top (dorsal spines) and 3 along the bottom (anal spines)  The pain they inflict & the reaction people can have when stung sounds very similar to the bark scorpion.

 

I found out they are SUPER tasty!  Especially since Bob Burroughs, 2nd Cook and Lito LLena, Chief Steward prepared them as ceviche – my favorite.

 

Fort Jefferson

In the afternoon we got a special treat.  We left the waters of the Florida Keys National Marine Sanctuary and ferried over to Fort Jefferson at the Dry Tortugas National Park for a tour and some snorkeling.  One can only reach the fort by boat or sea plane.  It was built between the years 1846 and 1875 as a way to claim the main shipping channel between the Gulf of Mexico, the western Caribbean and the Atlantic Ocean.  It never saw battle, mostly because it’s fire power was so massive that no one wanted to go up against it!

 

Even though I have been able to travel out into the open ocean on the small boats each day, it was SO GOOD to actually get into the water and snorkel around.  So many amazing things to see and take photos of.

 

There were many jelly fish (mostly Moon Jellies) and we all got stung a lot, but the underwater scenery was well worth it.

 

Bonus Points – make a COMMENT and tell me how the LION FISH and the GILA MONSTER are similar!

Answer to my last post:  It was a DOLPHIN.  The Common Bottlenose Tursiops truncatus

http://www.nmfs.noaa.gov/pr/species/mammals/cetaceans/bottlenosedolphin.htm

Also, the definition of RECIPROCITY is the practice of exchanging things with others for mutual benefit.

I have been so impressed with the seamless collaboration between the crew & science team as well as the different agencies within the science team.  Everyone gives of themselves so freely for the main goal of the scientific mission.