Kathleen Gibson, Time to Fish! July 29, 2015

High flyer away! Photo Credit : Kristin Hannan

High flyer away!
Photo Credit : Kristin Hannan

NOAA Teacher at Sea
Kathleen Gibson
Aboard NOAA Ship Oregon II
July 25-August 8, 2015

Mission: Shark Longline Survey
Geographic Area of the Cruise: Atlantic Ocean off the Florida and Carolina Coast
Date: July 29, 2015
Coordinates:
LAT 2933.3326N
LONG 8029.065W

Weather Data from the Bridge:
Wind speed (knots): 9.2
Sea Temp (deg C): 29.6
Air Temp (deg C):  28.7

Yesterday was the first full day of sampling.  We were off the coast of Miami, FL and it was relatively shallow.  I’m not sure how many sharks I expected to see on my first day, but certainly not the 80 + that we did catch!

Science and Technology Log –  A, B, C’s of Fishing for Sharks

Kristin Hannan preselected our stations following a random stratified approach. Sampling stations have A, B, or C designations, depending on the depth (A is more shallow than B or C). The night crew went on duty at midnight and completed one station yesterday morning.  We completed three stations during our shift yesterday and three more today.

The bridge lets us know when we’re 30 minutes from our  station, and we begin preparations. We bait the hooks with mackerel 20 minutes ahead of time.

When we get to the station, the longline is fed out from the stern of the ship and extends one mile.  A

Throwing Bait - I'm passing baited gangions to Tim Martin to attach to the Longline. Moments after this photo my TAS hat took flight and joined the sharks of the Atlantic.

Throwing Bait –
I’m passing baited gangions to Tim Martin to attach to the Longline. Moments after this photo my TAS hat took flight and joined the sharks of the Atlantic.

marker, called a high flyer, is attached to the beginning of the line. One hundred baited gangions are attached to the line at intervals after which another high-flyer marks the end of the line. The ship then returns to the starting point, the line is hauled in and the fun begins. If there is a shark on the line, the deck crew fisherman calls out “Shark On!”  That’s the signal for someone from the science group to step up and take the shark, remove the hook and collect data.

The following data collected is collected for all sharks:

  • Species
  • Precaudal Length: Nose to base of tail
  • Fork Length: Nose to fork of tail
  • Natural Length: Nose to tail
  • Total Length: Nose to end of tail when extended manually
  • Weight (Kg)
  • Sex Determination

Tag numbers and tissue sample collection is also noted if applicable.

Early morning haul back by the night shift. Video taken from the highest point on the ship. 

Most of the sharks caught were small enough to bring up and hand to the science team.  We use a wooden measuring board to determine lengths. Those that were a bit larger were brought up on deck by the fishermen and they required multiple handlers to collect data.

Very large sharks had to be measured with the help of a cradle and hoist.  The cradle is lowered to water level and large sharks are coaxed onto the cradle using the hook and line they are still attached to.  A hoist brings them to deck height for assessment.  Deck Operations Crew manages all shark retrieval and determines when is safe for us to proceed.

Atlantic Sharpnose

Atlantic Sharpnose Photo Credit: Kristin Hannan

Me holding a mature male Atlantic Sharpnose Photo Credit: Kristin Hannan

Most of the sharks that we’ve caught have been Atlantic Sharpnose.  This shark is relatively small (adults average 0.85 M) and are found in shallow Atlantic coastal waters from New Brunswick down into the Gulf of Mexico, and even off the coast of Brazil.  They are known by at least 8 common names in different regions.  My Biology students would recognize this as a good example of why it’s important to use agreed-upon scientific names for scientific research.  The scientific name for this species is Rhizoprionodon terraenova.  It has a long snout (longer than the width of the head) and most adults have a few white spots on a gray body.

Sharpnose mature relatively quickly and can begin producing offspring within two years; also, they can have up to 5-7 pups at once. These are major factors contributing to the abundance of this species.  In comparison, larger sharks may take up to 15 years to reach maturity and typically have fewer offspring in each brood.  

Our catch also included one Blacknose (Carcharhinus acronotus) and multiple Scalloped Hammerhead (Sphyrna lewini), Nurse (Ginglymostoma cirratum) and Spinner sharks (Carcharhinus brevipinna).

Larger specimens were brought to deck height using a cradle, for weight, size, and sex determination, and were lowered back into the water after being measured and tagged.

Nurse Shark in cradle

Nurse Shark in cradle (Photo Credit: Ian Davenport)

A Sandbar shark in the cradle. I'm in the yellow helmet tagging the shark.

A Sandbar shark in the cradle. I’m in the yellow helmet tagging the shark. ( Photo Credit: Erica Nu

 

Hook removal required bolt cutters after I tagged this Sandbar Shark.

Hook removal required bolt cutters after tagging  this Sandbar Shark.

 

Career Spotlight

If your interests tend toward science mixed with heavy machinery, skilled fishing, robotics or electronics, perhaps one of the following careers is for you.

Tim Martin: Chief Boatswain

Tim Martin Chief Boatswain

Tim Martin Chief Boatswain

As the Chief Boatswain, Tim Martin is responsible of all activities that happen on deck and he maintains constant communication with the bridge during all operations.  Tim came to NOAA fisheries with a wealth of experience gained while serving in the U.S. Navy and later as a commercial fisherman in the Pacific Northwest.  He was initially classified as a “Skilled Fisherman” with NOAA and has worked his way up to Chief Boatswain.

He and his group set and retrieve the longline. They also run all of the heavy deck equipment, such as the cranes that are used to position the shark cradle for large sharks and the CTD (water Sampling device).  The Chief Boatswain is also responsible for training new crewmembers and maintaining ship supplies.  In addition, Tim has earned Dive Master Certification through the NOAA Diving School, considered to be the best civilian diving school in the US.

 

 

Tim Martin and deck Crew cradling a Tiger shark. Note the wooden dowel at center used to attach tags. ( Photo Credit: Erica Nuss)

Tim Martin and deck crew cradling a Tiger shark. Note the wooden dowel at center used to attach tags. (Photo Credit: Erica Nuss)

When asked what keeps him going, Tim is very clear that he believes the work that NOAA Fisheries does is very important, and he is proud to be able to use his expertise to support NOAA’s efforts.  This satisfaction somewhat tempers the challenges of the job which include being at sea for at least 6 months of the year, and constantly being in a training flux. Tim feels a strong bond with his crew and there is a clear sense of mutual trust and respect among them. 

Ken Wilkinson: Electronic Technician (Supreme), NOAA Fisheries Engineering Unit

Ken has been with the Engineering Unit of NOAA Fisheries for 26 years.  The mission of his Unit is to

Ken using his skills to filet a Red Snapper

Ken using his skills to filet a Red Snapper

support NOAA Fishery research by developing innovative technology. Ken always wanted to work on the water and he initially studied Marine Biology in college, but he migrated toward electronics.  His work allows him to combine two great interests.  His work takes him to sea 50-80 days each year.

A major focus of the electronics unit is to support the Reef Fish program.  Trawling nets and longline apparatus will damage reef systems.  In order to assess reef fish populations in a non-invasive way, Ken and his group work a number of Remotely Operated Vehicles that capture still and moving images that can be used later to determine abundance and species diversity.   Ken’s unit has also developed a device called an Autonomous Underwater Vehicle (AUV). This programmable instrument scans the sea floor using lasers and  data collected is used to develop more accurate sea floor maps.

Bathymetric map of the Longline sampling area- NOAA

Bathymetric map of the Longline sampling area- NOAA

 

New device: Kennenator 5000 Dual Laser

Ken Wilkinson and his Kennenator 5000.

Ken Wilkinson and his Kennenator 5000.

Ken is on board the Oregon II testing his new device that can be used to assess the size of large sharks without bringing them to deck height. Ken’s device has two lasers set at a fixed distance from one another.  The beams are directed toward the shark while it remains at the surface of the water. Various measurements can be extrapolated from the laser measurement. Large sharks caught on the longline survey are typically brought to the surface in the cradle for assessment.  Cradle use is preferred as it allows tagging and tissue sample collection and sex determination. However, there are situations when this is not possible such as when poor weather conditions develop which limit sling operations, and some small vessels are not equipped with sling equipment.

Personal Log

The Challenge

The Challenge

The fast pace of the haul back at early stations was jarring.  I stepped up when “Shark On” was called and a writhing Sharpnose was thrust into my hands.  The first task is to get the hook out of the shark’smouth and this is no small feat.  The circle hook is designed is to reduce the chance that the shark will swallow the hook or get hurt by it, but getting these hooks out of the mouth without hurting the shark requires technique.  There will be plenty of opportunities to get the hang of in the next week.

A highlight of this first day was getting up close to a 2 meter long Scalloped Hammerhead brought to the surface in the cradle.  I was able to feel its head, observe its eyes, and place an identification tag near its dorsal fin before it was lowered back into the water.

Smaller Scalloped Hammerhead on deck. It took two of us to hold this one in place fore measuring and tagging.

Smaller Scalloped Hammerhead on deck. It took two of us to hold this one in place fore measuring and tagging. (Photo Credit: Ian Davenport)

 

Clare Wagstaff, June 2, 2008

NOAA Teacher at Sea
Clare Wagstaff
Onboard NOAA Ship John N. Cobb
June 1-14, 2008

Mission: Harbor seal pupping phenology and critical habitat study
Geographical Area: Southeast Alaska
Date: June 2, 2008

Weather Data from the Bridge 
Weather: Overcast
Visibility (nautical miles): 10
Wind Speed (knots): 12
Wave Height (feet): 1
Sea Water Temp (0C): 7
Air Temp (0C): 10.5

Science and Technology Log 

Late last night the JOHN N. COBB reached our anchor site at Tebenkof Bay (56O 23’N 134O 10’W). Situated just off the southern end of Chaptam Straight, the gentle rocking of the boat and the dull drone of the ship’s engine and generator had sent me off to sleep very quickly the night before. Keen to start the day though, and with the early morning sun shining in through my room’s porthole, I got up to a hearty breakfast and made ready to depart the COBB for a day of exploring. Around 06:30 the Chief Bosun (Joe), Dave, and I boarded the small skiff, referred to as the JC-1. The objective was to go visit known seal haulout sites that Dave had visited the year before. At each site the aim was to count the number of harbor seals present focusing particularly on the number of pups.

Equipment Required 

All of us on the JC-1 were dressed in cold weather and rain gear, even though it appeared to be a nice day, rain is always likely around this area! Dave kindly lent me his insulated Mustang survival gear to wear and I was very grateful! For conducting his research, Dave has certain pieces of equipment that he always brings when observing seals. To find the location of a known haulout site or to record the location of a newly discovered one, he has a handheld GPS that can accurately log coordinates. To observe the seals more closely Dave uses a pair of gyro-stabilized binoculars. These are essential as being on the water for most observations means the images produced through these binoculars are much clearer not as wobbly. For safety reasons, he also carries a satellite phone in case of emergencies and an PEPIRB in case of emergencies. A PEPIRB or Personal Epirb is a device that when activated, immediately notifies the US Coast Guard of your exact position by satellite. The data Dave collects is recorded on site in a waterproof notepad and through photographs that he regularly takes of the animals he observes.

An Ideal Site? 

The harbor seals typically haul out at low tide and seem to prefer sunny and warmer periods during the day, roughly between 11:00 and 16:00 hours. Unfortunately today, because of the tide cycle we were venturing out as the tide was gradually rising and much earlier in the day then is optimal to see the seals on land. However, there were a few seals present but their numbers were greatly reduced when compared to last year’s data. Dave did not seem overly concerned though because of the time of day we were making the counts. What was surprising was that certain sites we past looked like ideal locations for the seals to haulout on to. Seals like a variety of substrate (rock or sand), a reef with a steep drop off into the water, wind speed not above 35-40mph and good visibility to be able to see predators. We saw a number of sites that fit this description but there was a distinct lack of seals to be found at them, with no real explanation why. Researchers still have more to learn about seals and hopefully this cruise will add more data to help understand their behavior and choices.

Sea otters around Tebenkof Bay. Note the female in the center of the photograph carrying a baby on her stomach

Sea otters around Tebenkof Bay. The female in the center of the photograph carryies a baby on her stomach

Sea Otters 

One of the most interesting animals we observed today was a large number of sea otters. The otters regularly haul themselves out on to the rocks, like seals do, and seem to frequently be in the same area as the seals. While watching them in the water, a large number of the females were floating or swimming with a youngster on their stomachs! Otters, unlike seals, have little insulation so this technique demonstrated could be a method to protect the young from the elements and keep them safe near the parent. The key to making good observations of any of these wild animals is to approach them slowly and avoiding doing so head on. As we got closer, Jon would switch off the engine so as not to frighten or startle them. Unfortunately, when they do feel threaten, both the sea otters and harbor seals retreat back into the water. This happened on a number of occasions when we got a little too close for their comfort. This obviously makes the observations, identification and assessment of population numbers more challenging.

The entrance to Little Port Walter harbor. The ‘White House’ is where the researchers and seasonal workers live. Photograph courtesy of Dave Withrow.

The entrance to Little Port Walter harbor. The ‘White House’ is where the researchers and seasonal workers live.

Biological Field Station – Little Port Walter 

After approximately two and a half hours of observations we returned back to the COBB. The ship then set course for Little Port Walter, a NOAA Biological Field Station. It is a remote location but manned all year round. “Our nearest neighbors are only six miles away,” comments caretaker, Brad Weinlaeder. Access to this area is via boat or seaplane, so when the COBB docks here with a shipment, possibly four or five times a year, it receives a welcoming reception. Set in a beautiful bay off Chatham Strait, the residents say it gets the most rain anywhere in North America: and it is not hard to believe as a downpour starts as we arrive! The beautiful temperature rainforest around the bay is thanks to the plentiful rainfall it receives each year. But there’s a reason to have a research station in this location, and that reason is salmon. Each year the hatchery on site breeds a variety of fish for release into the wild, the most recent fish to be released where king salmon.

Tagging a Fish 

Brad Weinlaeder showing the incubation trays for the salmon eggs at the Biological Field Station at Little Port Walter.

Brad Weinlaeder showing the incubation trays for the salmon eggs at the Biological Field Station at Little Port Walter.

Although king salmon are not native to this particular section of water (the water is not cold enough), being the biggest and most rare specie of salmon gives them reasons to be studied. The eggs and sperm are collected from trapped king salmon when they reach sexual maturity and return to Little Port Walter, four to five years later. The fertilized eggs, the size of a pearl, are then incubated in early August for nine months until they are released. Unfortunately, that means that we had missed their release by just a few weeks. The process of producing these fish requires a variety of steps including identifying the fish by visual methods and internal tagging. The adipose fin (located between the dorsal and caudal fin) is simply cut off before the captive bred fish is released. Apparently this does not give the fish a survival disadvantage, but is a visual sign that it has been bred in captivity. Each fish released from the hatchery also has a small, stainless steal, identification tag placed in its nose.

When this fish returns to Little Port Walter at sexual maturity, the fish is collected and the tag removed. So small is this tag that that Brad comments, “it’s like trying to find a needle in a hay stack!” Yet this tag gives vital background information about the fish that is then used in selecting the best fish to breed with. Unfortunately removing the tag is fatally invasive. There are other methods for tracking fish that would allow it to survive such as using a small microchip, just like the ones used in identifying cats and dogs today. However, at ten times the price and requiring much more precision to insert it into the fish, is not a practical option on a large scale here. Especially as the fish are caught on their return migration and are already in the last stages of life. Held in giant fresh water tanks, the king salmon matures on a high protein pellet diet that not only they like, but so does the local bear population. It is common practice around Little Port Walter to carry a gun with rubber bullets. A wide shot fired is hopefully just enough to scare them away! This year the hatchery released 214,000 king salmon out into the wild. With an average 3% survival rate, only 1.5% will make it through their four to five year life span to return back to Little Port Walter. Fishermen will catch the other 1.5%.

Other Research 

There is a great deal of other research going on here at Little Port Walter. Currently in progress is the study of rockfish and their preferred habitat substrate in relation to predation. In the past scientists have also studied slug migration and tree ring analysis for the presence of iodine as it relates to fish populations. What makes this marine research station so important is that it has data going back to 1936, when it first opened. Researcher’s come from thousands of miles to compare what they find, to data that is already known and recorded here at Little Port Walter. Pretty fascinating stuff!

View of the hatchery where the salmon are placed when they are approximately 5-6cm long. Here they are fed and fresh water from upstream constantly flows into these holding tanks.

The hatchery where the salmon are when they are approximately 5-6cm long. They are fed and fresh water from upstream constantly flows into the holding tanks.

Personal Log 

Unfortunately, today was the day I experienced by first bout of sea-sickness! I had begun to feel that I had got my ‘sea legs’. But I had spoken too soon! After returning from our morning of observations, the COBB departed for Little Port Walter. In the late morning the ship began to cross Chatham Straight. The COBB was hitting 4-6ft high waves and crossing them at an angle called courtering. This means that the boat was yawing, which is a combination of a pitching motion (see-saw action) and rolling (side to side), basically bobbing around like a cork! As the motion got stronger, my stomach got weaker and I ended up out on the starboard deck trying to look at the horizon and stop feeling ill. Thankfully though the effects wore off quickly as the ship’s ride became smoother. Hopefully the rest of the cruise will be smoother!

Question of the Day for Miss Wagstaff’s Science Class 

Research in the field can be very different to research done in a laboratory at school. From the description written above about today’s seal study, try to think about the ways they differ. Consider such factors as time, variables, data collection etc.