fish traps – NOAA Teacher at Sea Blog

July 24, 2019July 24, 2019

David Madden: Engines, Dolphins, and Sharksuckers, July 24, 2019

NOAA Teacher at Sea

David Madden

Aboard NOAA Ship Pisces

July 15-29, 2019

Mission: South East Fishery-Independent Survey (SEFIS)

Geographic Area of Cruise: Atlantic Ocean, SE US continental shelf ranging from Cape Hatteras, NC (35°30’ N, 75°19’W) to St. Lucie Inlet, FL (27°00’N, 75°59’W)

On board off the coast of South Carolina – about 50 miles east of Charleston (32°50’ N, 78°55’ W) – after a slight change of plans last night due to the approaching tropical depression.

Date: July 24, 2019

Weather Data from the Bridge:
Latitude: 32°50’ N
Longitude: 78°55’ W
Wave Height: 3-4 feet
Wind Speed: 15 knots
Wind Direction: Out of the North
Visibility: 10 nm
Air Temperature: 24.6°C
Barometric Pressure: 1011.8 mb
Sky: Cloudy

NOAA Pisces Full Track 7-20-19 — This is a map from the other day outlining the path of the ship. The convoluted pattern is the product of dropping off and picking up 24 (6 x 4) fish traps per day, along with the challenges of navigating a 209 foot ship in concert with gulf stream currents and winds.

Science and Technology Log

Life and science continue aboard NOAA Ship Pisces. It seems like the crew and engineers and scientists are in the groove. I am now used to life at sea and the cycles and oddities it entails. Today we had our first rain along with thunderstorms in the distance. For a while we seemed to float in between four storms, one on the east, west, north, and south – rain and lightning in each direction, yet we remained dry. This good thing did indeed come to an end as the distant curtains of rain closed in around us. The storm didn’t last long, and soon gathering the fish traps resumed.

Dave with red grouper — Processing fish: measuring length and weight of a red grouper, *Epinephelus morio*.

Fish Count for July 23, 2019 — Yesterday’s fish count. Compare to other day’s catches: Tons of vermillion snapper, tomtate, and black sea bass. And one shark sucker (read on for more). Thank you, Zeb, for tallying them up for me.

The highlight of yesterday (and tied for 1^st place in “cool things so far”) was a tour of the engine room lead by First Assistant Engineer, Steve Clement. This tour was amazing and mind-blowing. We descended into the bowels of the ship to explore the engine rooms and its inner workings. I think it rivals the Large Hadron Collider in complexity.

I kept thinking, if Steve left me down here I would surely get lost and never be found. Steve’s knowledge is uncanny – it reminded me of the study where the brains of London cab drivers were scanned and shown to have increased the size of their hippocampus. (An increase to their memory center apparently allows them to better deal with the complexities of London’s tangled streets.) And you’re probably thinking, well, running a massive ship with all its pipes and wires and hatches and inter-related, hopefully-always-functioning, machinery is even harder. And you’re probably right! This is why I was so astounded by Steve’s knowledge and command of this ship. The tour was close-quartered, exceptionally loud, and very hot. Steve stopped at times to give us an explanation of the part or area we were in; four diesel engines that power electric generators that in turn power the propeller and the entire ship. The propeller shaft alone is probably 18 inches in diameter and can spin up to 130 rpm. (I think most of the time two engines is enough juice for the operation). Within the maze of complexity below ship is a smooth running operation that allows the crew, scientists, and NOAA Corps officers to conduct their work in a most efficient manner.

Dave and Steve and engines — First Assistant Engineer Steve Clement and TAS Dave Madden in the Engine Room

I know you’ve all been wondering about units in the marine world. Turns out, students, units are your friend even out here on the high seas! Here’s proof from the bridge, where you can find two or three posted unit conversion sheets. Makes me happy. So if you think that you can forget conversions and dimensional analysis after you’re finished with high school, guess again!

Speaking of conversions, let’s talk about knots. Most likely the least-understood-most-commonly-used unit on earth. And why is that? I have no idea, but believe me, if I were world president, my first official action would be to move everyone and everything to the Metric System (SI). Immediately. Moving on.

Back to knots, a unit used by folks in water and air. A knot is a unit of speed defined as 1 nautical mile/hour. So basically the same exact thing as mph or km/hr, except using an ever-so-slightly-different distance – nautical miles. Nautical miles make sense, at least in their origin – the distance of one minute of longitude on a map (the distance between two latitude lines, also 1/60 of a degree). This works well, seeing as the horizontal lines (latitude) are mostly the same distance apart. I say mostly because it turns out the earth is not a perfect sphere and therefore not all lines are equidistant. And you can’t use the distance between longitude lines because they are widest at the equator and taper to a point at the north and south pole. One nautical mile = 1852 meters. This is equal to 1.15 miles and therefore one knot = 1.15 miles/hour.

This next part could double as a neato fact: the reason why this unit is called a “knot” is indeed fascinating. Old-time mariners and sailors used to measure their speed by dropping a big old piece of wood off the back of the boat. This wood was attached to some rope with knots in it, and the rope was spun around a big spool. Once in the water the wood would act kind of like a water parachute, holding position while the rope was let out. The measuring person could then count how many evenly spaced knots passed by in a given amount of time, thus calculating the vessel’s speed.

Personal Log

The scientists on board have been incredibly helpful and patient. Zeb is in charge of the cruise and this leg of the SEFIS expedition. Brad, who handles the gear (see morning crew last post), is the fishiest guy I’ve ever met. He seriously knows everything about fish! Identification, behavior, habitats, and most importantly, how extract their otoliths. He’s taught me a ton about the process and processing. Both Zeb and Brad have spent a ton of time patiently and thoroughly answering my questions about fish, evolution, ecology, you name it. Additionally, NOAA scientist Todd, who seeks to be heroic in all pictures (also a morning crew guy), is the expert on fish ecology. He has been exceptionally patient and kind and helpful.

The fish we’re primarily working with are in the perches: Perciformes. These fish include most of your classic-looking fish. Zeb says, “your fish-looking fish.” Gotcha! This includes pretty much all the fish we’re catching except sharks, eels, and other rare fish.

For more on fish evolution here are two resources I use in class. Fish knowledge and evolution: from Berkeley, A Fisheye View of the Tree of Life.

Fish Tree of Life Berkeley — Fish Tree of Life, from University of California-Berkeley

And check out Neil Shuban’s Your Inner Fish series.

General Updates:

Plenty of exciting animals lately. Here’s a picture of those spotted dolphins from the other day.
The weather has been great, apart from yesterday’s storm. Sunrises and sunsets have been glorious and the stars have been abundant.
We found a common octopus in the fish trap the other day. The photo is from crew member Nick Tirikos.
I’m missing home and family. I can’t wait to see my wife and son.
That tropical depression fizzed out, thankfully.

common octopus — Common Octopus (Photo by crewmember Nick Tirikos)

Neato Facts =

Yesterday we caught a shark sucker in the fish trap. I was excited to see and feel their dorsal attachment sucker on top of their head.

Hold on. I just read more about these guys and turns out that sucking disc is their highly modified dorsal fin! That is the most neato fact so far. What better way to experience the power of this evolutionarily distinct fish than to stick it to your arm?! The attachment mechanism felt like a rubber car tire that moved and sealed against my skin. (Brad calls them sneakerheads).

Consider all the possible biomimicry innovations for the shark sucker’s ability to clasp onto sharks and fish and turtles while underwater. This grasp and release adaptation surely has many cool possible applications. Here are a few: Inspiring New Adhesives. Robotic Sticky Tech. Shark Sucker biomimicry

I’d love to hear your questions and comments!

July 17, 2018July 17, 2018

David Knight: Work Out and Work Up: Part I, July 17, 2018

NOAA Teacher at Sea

David Knight

Aboard NOAA Ship Pisces

July 10-23, 2018

Mission: Southeast Fishery-Independent Survey

Geographic Area: Southeastern U.S. coast

Date: July 17, 2018

Weather Data from the Bridge:

Latitude: 30° 30.2 N
Longitude: 80° 15.6 W
Sea wave height: 1-2 ft
Wind speed: 15 kts
Wind direction: 187°
Visibility: 10 nm
Air temperature: 30.1 °C
Barometric pressure: 1014.7 mB
Sky: Broken Clouds

Science and Technology Log

Warning!!! Great Science Ahead…

Part I.

Waiting to see what the traps have brought up this time… (photo by David Knight)

As fish traps begin to be brought up by the deck crew, scientist wait to see what may be in the trap. I’ve actually found that I am looking over the deck in anticipation of new fish that may have been caught, or to see how many fish will need to be “worked up.” Once the fish have been removed from the trap and emptied into a large bin, they are then sorted by species into 17-gallon bins to determine the total weight of all fish. Moving 17 gallons worth of fish up to the lab bench to the scale can be quite a “work out.” There have been a couple of hauls that have captured so many fish of a particular species that more than one bin has to be used. After the fish have been weighed, the total length of each fish is determined to get a length frequency of the entire catch. For species like Tomtate (Haemulon aurolineatum), every fish is measured and then returned to the ocean. For some species, a pre-determined percentage are kept for a more detailed work up that may include the extraction of otoliths, removal of gonads, or a collection of stomach contents. The data collected from each fish will then be used by scientists in a number of different agencies and in different states to better understand the growth and reproduction of the particular species. All of this data is then used to create management plans for economically and ecologically important fish as well as to gain a better understanding of its life history.

Work Up

Length.

Measuring fish — Measuring the length of each, individual fish. (photo taken by Nate Bacheler)

One may assume that a very long fish is also very old, but that is not necessarily the case. The length of a fish is not a good way to determine the age of a fish because factors such as temperature and food availability may alter the growth rate. Many fish grow very rapidly early on, but then slow their growth, so it is possible that a fish that is twelve years old is the same size as a fish that is three years old. Because many fish demonstrate logistic growth rates in terms of length, it is important to use additional pieces of data to determine their age.

Otolith.

In the head of ray-finned fish, one can find small, bone-like structures called otoliths. These structures have a variety of sensory functions that include detection of sound vibrations in water, movement, and its orientation in the water. As fish age, calcium carbonate will be added to the otolith, forming ring-like structures that can be used to determine the age of a fish, much like a tree will add new tissue each season forming tree rings. Otoliths are the best way to determine the actual age of a fish.

For the fish that we were sampling, we remove the sagittal otoliths which are located beside the brain just about level with the eyes. To extract them, a cut is made on the dorsal side of the fish with a sharp knife to gain access to the skull case. To extract otoliths from some very “hard-headed” fish, a saw is used, while others take little effort. After a few hours of otolith extraction, I feel as though I am getting the hang of it, although I am nowhere near as fast as the biologist on board! I’ve been collecting otoliths from Black Sea Bass (Centropristis striata) and Vermillion Snapper (Rhomboplites aurorubens) to bring home with me to create a lab for my class and to post on the NOAA Teacher-at-Sea website.

Extracting otolith — Looking for a perfect extraction of otolith from Vermilion Snapper. (photo taken by Nate Bacheler)

Be sure to check back for Part II. Gonads, Diet and DNA

Personal Log

The motion of the ship has not been a problem so far and I stopped taking any motion sickness pills after the first day. As I have been removing otoliths from fish, I cannot help but think about the similarities in how both fish and humans perceive their spatial environment and maintain balance. In our vestibular system, we too have otoliths that help to sense acceleration in a vertical and horizontal direction. Of course my thoughts then go to a dark place…what if someone were removing my otoliths to determine my age?

Did You Know?

The longest known life span in vertebrates is found in the Greenland Shark (Somniosus microcephalus). It is estimated that the Greenland shark grows less than 1 cm per year. Since sharks do not have otoliths, scientist have to analyze proteins found in the lens of their eye. In 2016, scientist from the University of Copenhagen collected a 5 m shark that was estimated to be about 392 years old, but may be anywhere from 272 to 512 years old.

Reference: Eye lens radiocarbon reveals centuries of longevity in the Greenland shark (Somniosus microcephalus). Science 12 Aug 2016: Vol. 353, Issue 6300, pp. 702-704

July 13, 2012August 11, 2021

Carmen Andrews: A Fishing Expedition in the Atlantic, Continued, July 13, 2012

NOAA Teacher at Sea
Carmen Andrews
Aboard R/V Savannah
July 7 – 18, 2012

Mission: SEFIS Reef Fish Survey
Location: Atlantic Ocean, off the coast of Daytona Beach, Florida
Date: July 13, 2012

Latitude: 29 ° 19.10’ N
Longitude: 80 ° 24.31’ W

Weather Data:
Air Temperature: 28.3° C (82.94°F)
Wind Speed: 12 knots
Wind Direction: from Southeast
Surface Water Temperature: 27.48 °C (81.46°F)

Weather conditions: Sunny and Fair

Science and Technology Log

Catching bottom fish at the reef

As the fish trap lies at the bottom of the ocean at the reef site, fish can enter and exit freely through the opening.

Red snapper swimming near a fish trap — Red snapper swimming near a sunken fish trap

At the end of approximately 90 minutes, the R/V Savannah returns to the drop site and begins the process of raising the trap with whatever fish remain inside. The six traps are pulled up in the order in which they were dropped.

Scientists and crew waiting to arrive at a trap location

The crew member on watch in the wheelhouse will maneuver the boat toward the paired poly ball buoys at a speed of about 5 knots. The boat draws alongside each pair on the starboard side.

R/V Savannah approaching poly ball buoys on the starboard side

One of the scientists throws a grappling hook toward the line that links the poly balls.

Throwing the grappling hook to secure buoys

The line is hauled in and passed to a waiting scientists, who pull the poly balls on deck. There is substantial hazard associated with this step. Undersea currents can be very powerful near the bottom where traps are set. As scientists are pulling in the cable by hand, unexpected current force can yank the trap cable, rope and buoys out of their hands and off the deck in an instant. If personnel on deck aren’t mindful and quick to react, the speeding rope can cause serious rope burn injury.

Nate is pulling poly balls and rigging onto the deck, as Adam P. gets ready to take the line

The cable connecting the fish trap and the poly balls is pulled in and threaded through the pulley system of a pot hauler. The pot hauler is an automated lifting tool that is operated by the second crew member on watch. At this time the first crew member on watch has left the wheel house and is piloting the boat from a small cab on deck above the pot hauler, so he can monitor the action below.

Pot hauler hoisting the fish trap to the boat

The pot hauler makes a distinctive clicking sound as it draws the trap toward the surface at an angle. It can take one to five minutes to raise the trap to the deck, depending on the depth of the water.

As the fish trap becomes visible, shimmering rapidly changing shapes can be seen as fishes’ bodies catch and reflect sunlight.

Fish trap breaking the surface of the water

The trap clears the water and gets pulled aboard.

Grabbing the fish trap and pulling it aboard

Very quickly, and with two scientists holding each side, the trap is upended onto its nose and suspended above the deck. A third scientist opens the trap door at the bottom and the fish are shaken into a plastic bin.

Orienting the fish traps to ready them for dumping into bins — Orienting a fish trap to ready it for dumping the catch into a bin

Freshly caught red snapper and black sea bass

Ice pellets are shoveled onto the fish and a cover is snapped on the bin. If the catch is small, fish may be placed in a bucket or tub and cover with ice.

Fish are covered in ice before the bin cover is snapped on

A numbered tag is removed from the trap and tied onto the bin to identify specimens from each catch. The containers holding the day’s catch are set aside for later processing.

Every so often, unexpected sea life is brought up in the traps. The catch has included sea stars, sea urchins, several kinds of tropical fish and many moray eels.

Moray eel slithering on the deck. A moray’s bite can be very severe.

Video cameras are also removed from the top of the trap. Their data cards will be downloaded. Fish behavior and surrounding habitat videos will be analyzed, along with anatomical specimens and size data taken from the fish themselves in the wet lab.

Personal Log

Every day brings more wildlife encounters and sightings. I am dazzled by the many fascinating organisms I’ve been able to see up close. Sometimes I am quick enough to grab my camera and put the animal into my view finder, focusing clearly enough to catch a great image. Here are a few of those images (including some new friends from the cruise):

A sheerwater -- bird found in open water — A sheerwater — bird found in open water

Sheerwaters dive beneathe the surface to catch fish. — Sheerwaters dive beneath the surface of the water to catch fish. This bird is consuming a fish with its wings open to balance itself on the water.

Other times I have to capture a memory. Last night I tried reef fishing. I have no experience fishing. At all. Adam P. handed me his own rod and reel. The hook was baited and the line was already lowered to the bottom, down at around 40 meters (more than 120 feet).

Shortly after I took it, the tip of the rod began to bend downward and pull. I asked Adam if that meant something had been hooked. He said, “Go ahead. Reel it in.” That’s when I discovered that even recreational fishing is tough work – particularly this unfamiliar technique of holding the rod with the right hand and reeling in with the left. Neophyte to fishing is me.

When the fish got to the surface, Adam took the big, beautiful black sea bass off the hook for me. On the deck it splayed out the spines of its dorsal, caudal and pectoral fins defensively. I was concerned because the fish’s air bladder was hanging out of its mouth from its rapid ascent to the surface. Adam punctured the air bladder to deflate it. He threw the fish back into the sea at my request, and assured me that the fish will go on with its life. I’m optimistic it will.

July 10, 2012August 11, 2021

Carmen Andrews: News from Somewhere in the Atlantic Ocean off the Coast of Georgia, July 9, 2012

NOAA Teacher at Sea
Carmen Andrews
Aboard R/V Savannah
July 7 – July 18, 2012

Mission: SEFIS Reef Fish Survey
Geographical Location: Atlantic Ocean, off the coasts of Georgia and Florida
Date: July 9, 2012

Location Data:
Latitude: 30 ° 54.55’ N
Longitude: 80 ° 37.36’ W

Weather Data:
Air Temperature: 28.5°C (approx. 84°F)
Wind Speed: 6 knots
Wind Direction: from SW
Surface Water Temperature: 28.16 °C (approx. 83°F)
Weather conditions: Sunny and fair

Science and Technology Log

Purpose of the research cruise and background information

The Research Vessel, or R/V Savannah is currently sampling several species of fish that live in the bottom or benthic habitats off the coasts of Georgia and Florida.

Reef fish study area — The coastal zone of Georgia and Florida and the Atlantic Ocean area where the R/V Savannah is currently surveying reef fish

These important reef habitats are a series of rocky areas that are referred to as hard bottom or “live” bottom areas by marine scientists. The reef area includes ledges or cliff-like formations that occur near the continental shelf of the southeast coast. They are called ‘reefs’ because of their topography – not because they are formed by large coral colonies, as in warmer waters. These zones can be envisioned as strings of rocky undersea islands that lie between softer areas of silt and sand. They are highly productive areas that are rich in marine organism diversity. Several species of snapper, grouper, sea bass, porgy, as well as moray eels, and other fish inhabit this hard benthic habitat.

Reef fish — Hard bottom of reef habitat, showing benthic fish — black sea bass is on left and gray trigger fish is on right side of image.

It is also home to many invertebrate species of coral, bryozoans, echinoderms, arthropods and mollusks.

Bottom organisms pulled up with fish traps — Bottom-dwelling organisms, pulled up with fish traps deployed in the reef zone.

The rock material, or substrate of the sea bottom, is thought to be limestone — similar to that found in most of Florida. There are places where ancient rivers once flowed to a more distant ocean shoreline than now. Scientists think that these are remnants of old coastlines that are now submerged beneath the Atlantic Ocean. Researchers still have much to discover about this little known ocean region that lies so close to where so many people live and work.

The biological research of this voyage focuses primarily on two kinds of popular fish – snappers and groupers. These are generic terms for a number of species that are sought by commercial and sports fishing interests. The two varieties of fish are so popular with consumers who purchase them in supermarkets, fish markets and restaurants, that their populations may be in decline.

Red snapper close up — Red snapper in its reef habitat

At this time, all red snapper fishing is banned in the southeast Atlantic fishery because the fish populations, also known as stocks, are so low.

How the fish are collected for study

The fish are caught in wire chevron traps. Six baited traps are dropped, one by one from the stern of the R/V Savannah. The traps are laid in water depths ranging from 40 to 250 feet in designated reef areas. Each trap is equipped with a high definition underwater video camera to monitor and record the comings and goings of fish around and within the traps, as well as a second camera that records the adjacent habitat.

Chevron fish trap — Fish swimming in and out of a chevron fish trap

I will provide the details of the fish trapping and data capture methods in a future blog.

Who is doing the research?

When not at sea, the R/V Savannah is docked at the Skidaway Institute of Oceanography (SKIO)on Skidaway Island, south of Savannah, Georgia. The institute is part of the University of Georgia. The SKIO complex is also the headquarters of the Gray’s Reef National Marine Sanctuary. The facility there has a small aquarium and the regional NOAA office.

The fisheries research being done on this cruise is a cooperative effort between federal and state agencies. The reef fish survey is one of several that are done annually as part of SEFIS, the Southeast Fisheries Independent Survey. The people who work to conduct this survey are located in Beaufort, North Carolina. SEFIS is part of NOAA.

The other members of the research team are from MARMAP, the Marine Research Monitoring Assessment and Prediction agency, which is part of the South Carolina Department of Natural Resources . This team is from Charleston, South Carolina.

Carmen, suited up to retrieve fish from traps — Mrs. Andrews, on deck near the stern of the R/V Savannah, getting ready to unload fish traps

NOAA also allows “civilians” like me — one of the Teachers at Sea– as well as university undergraduate and graduate students to actively participate in this research.

July 25, 2011April 28, 2021

Walter Charuba: Trap Deployment, July 21st, 2011

NOAA Teacher at Sea
Walter Charuba
Aboard R/V Savannah
July 18 — 29, 2011

Mission: Reef Fish Survey
Geographical Area: Southeast Atlantic Ocean
Date: July 21, 2011

Science and Technology Log

Dear Blog Aficionados,

Today I saw two different types of sea turtles, a bunch of jelly fishes, dolphins, and the people on the boat. It has been a beautiful day and I am trying to rest up because it is going to be a long day and night of setting up traps and categorizing fish. The weather here is hot and somewhat clear. I believe there is a high pressure system over us at this time. However, when you look over the coast of Florida there are these extremely large rain clouds, which are cumulonimbus clouds, rising into the sky. The sky is clear all around the boat and suddenly there is this large mass of clouds. Last night was very memorable when a lightning storm intermittently made this region glow. I stood at the bow, stern, port side, or starboard side in wonder of this spectacle. (Hopefully I will learn locations by the end of the trip.)

The last time I wrote about myself I was a bit nauseated, which does not do much for the self-esteem. My name is Walter Charuba and I have been teaching for a number of years. (This is code for not wanting to give you a specific number.) I am lucky to work for Grosse Pointe Schools at a great school called Brownell Middle School. I am also lucky to live in Grosse Pointe Farms and I actually live about a half a block from my school. This makes my carbon footprint sort of a toe print.

I have won numerous teaching awards such as Best Dressed Teacher, Youngest Looking Teacher (I hand out treats for this one.) and Teacher Who Lives Closest to School. After filling out the forms and passing the physical, and these examples from my wonderful resume, I was lucky enough to be chosen for the NOAA Teacher at Sea Program. Seriously, I do feel very fortunate to be part of this program and learning from these scientists.

You now may be wondering what exactly am I doing on this wonderful boat called the Savannah? (If you are not wondering about it, could you change your focus, because this concerns my next paragraph!) I am assisting in a very large fisheries survey by setting up fish traps, deploying of fish traps, and collecting data about the fish. When laid flat, the fish traps are six by five feet across and two feet deep. In these traps we place 24 menhaden bait fish, which are a close relative to the herring, if that means anything to you.

Then 5 to 6 traps are dropped off the back of the boat with special cameras to record activity around the trap. These cameras take about ninety minutes of footage. The traps also have two buoys connected to them to assist in collection. The areas where the traps are dropped are designated by the Chief Scientist, Warren Mitchell. Using sonar, Warren has to consider depth, currents, distance, topography, and a time schedule. Not an easy decision.

Science Watch Chiefs, Sarah Goldman and David Berrane, have to make certain the drop offs go smoothly. They have to make certain there are enough bait in the traps, and if all materials are ready for a perfect drop. Trap and data collection are another major responsibility of the chief scientists, and this will be the topic of the next blog.

Thanks for reading,

Walt (Mr. Charuba to my students.)