Maureen Anderson: Status of Sharks, August 3, 2011 (Post #5)

NOAA Teacher at Sea
Maureen Anderson
Aboard NOAA Ship Oregon II
(NOAA Ship Tracker)
July 25 — August 9, 2011

Mission: Shark Longline Survey
Geographical Area: Southern Atlantic/Gulf of Mexico
Date: August 3, 2011

Weather Data from the Bridge
Latitude: 32.50 N
Longitude: -079.22 W
Wind Speed: 17.75 kts
Surface Water Temperature: 28.60 C
Air Temperature: 29.90 C
Relative Humidity: 71%
Barometric Pressure: 1009.06 mb

Science and Technology Log
One reason the shark longline survey exists is because the populations of many types of sharks are in decline. There are several reasons for this – finning is one reason. “Finning” is the process where the shark’s fin is removed from the rest of its body. Since usually only the fin is desired, the rest of the body is discarded. Shark fins are used for things like shark fin soup – a delicacy in Asian cultures. When the fin is cut off and the rest of the body stays in the water, the shark can not swim upright and eventually dies. While some regulations have been passed to prevent this, shark finning still occurs. Sharks are also overfished for their meat. As a result many shark species have become vulnerable, threatened or endangered. Large sharks can take longer to reproduce. Therefore, they are more likely to be threatened or decline in their numbers.

endangered species chart

There are different categories of extinction risk, from "least concern" to "extinct" (photo courtesy of IUCN)

marine food chain

Sharks are at the top of the food chain. They are apex predators. (photo courtesy of Encyclopaedia Britannica)

Sharks are at the top of the food chain. They keep prey populations in control, without which the marine ecosystem would be unstable.

This is why the mission of the shark longline survey is important. The identification tags and roto tags used during this survey along with the data collected will help scientists assess the abundance of species in this area. They can then provide recommendations for shark management.  On average, we are collecting data on 10 sharks per line (or 10%), although our catch rates are between 0% and around 50%.  With 50 stations in all, that would be data on approximately 500 sharks (on average).

There are more than 360 species of known sharks. Below is a list of some that we have seen and measured during our survey. The IUCN red list (International Union for Conservation of Nature and Natural Resources) classify these sharks with a status:

Atlantic Sharpnose Shark – Least Concern
Blacknose Shark – Near Threatened
Silky Shark – Near Threatened
Tiger Shark – Near Threatened
Lemon Shark – Near Threatened
Dusky Shark – Vulnerable
Sandbar Shark – Vulnerable
Scalloped Hammerhead – Endangered

During my shift, we sometimes catch things we do not intend to catch.  We might reel in fish or other sea creatures that get caught on the hooks. This is called “bycatch”. While everything is done to try to catch only the things we are interested in studying, bycatch occasionally happens. The fish are only on our line for 1 hour, so their survival rates are pretty good. Our bycatch data is a very important element and also contributes to management plans for a number of species like snappers and groupers.

longline gear

Our longline gear includes two high flyer buoys, and hooks that are weighted down so they reach the bottom.

Just the other day, we caught a remora (a suckerfish that attaches itself to a shark’s side). Remoras and sharks have a commensalism relationship – the remora gets leftover food bits after the shark eats, but the shark gets no benefit from the remora. We quickly took down its measurements in order to get it back into the water quickly. Other bycatch included an eel, and black sea bass.

sharksucker

This sharksucker is an example of bycatch.

moray eel

This moray eel accidentally found its way onto a hook.

black sea bass

Bycatch - a black sea bass.

otoliths

This otolith (tiny white bone in center) helps this red snapper with its sense of balance.

We also caught a red snapper. Our chief scientist, Mark, showed me the two small, tiny ear bones called “otoliths” in the snapper’s head. These bones provide the fish with a sense of balance – kind of like the way our inner ear provides us with information on where we are in space (am I upside down, right side up, left, right?). You can tell the age of a snapper by counting the annual growth rings on the otoliths just like counting growth rings on a tree.

Personal Log

My experience aboard the Oregon II has given me a better understanding of the vulnerability of some shark species. While many of us may think that sharks can be threatening to humans, it is more accurate the other way around. Sharks are more threatened by humans than humans are threatened by sharks. This is due to our human behaviors (mentioned above).

Today I saw dolphins following our boat off the bow.  There were about 6  or 7 of them all swimming together in a synchronized pattern (popping up for air all at the same time).  It was really quite a treat to watch.

I’m also amazed by the amount of stars in the sky.  With the lights off on the bow, you can really see a lot of stars.  I was also able to see the milky way.  There have been many storms off the horizon which are really cool to watch at night.  The whole sky lights up with lightning  in the distance, so I sat and watched for a while.  With tropical storm Emily coming upon us, we may have to return to port earlier than planned, but nothing is set in stone just yet.  I hope we don’t have to end the survey early.

Species Seen :

Tiger Shark
Atlantic Sharpnose
Nurse Shark
Barracuda
Remora
Black Sea Bass
Snowy Grouper
Atlantic Spotted Dolphins
Loggerhead Turtle
Homo Sapiens

Becky Moylan: Preliminary Results, July 13, 2011

NOAA Teacher at Sea
Becky Moylan
Onboard NOAA Ship Oscar Elton Sette
July 1 — 14, 2011


Mission: IEA (Integrated Ecosystem Assessment)
Geographical Area: Kona Region of Hawaii
Captain: Kurt Dreflak
Science Director: Samuel G. Pooley, Ph.D.
Chief Scientist: Evan A. Howell
Date: July 13, 2011

Ship Data

Latitude 1940.29N
Longitude 15602.84W
Speed 5 knots
Course 228.2
Wind Speed 9.5 knots
Wind Dir. 180.30
Surf. Water Temp. 25.5C
Surf. Water Sal. 34.85
Air Temperature 24.8 C
Relative Humidity 76.00 %
Barometric Pres. 1013.73 mb
Water Depth 791.50 Meters

Science and Technology Log

Results of Research

Myctophid fish and non-Myctophid fish, Crustaceans, and gelatinous (jelly-like) zooplankton

Crustaceans

Chief Scientist guiding the CTD into the ocean

Chief Scientist guiding the CTD into the ocean

Beginning on July 1st, the NOAA Integrated Ecosystem Assessment project (IEA) in the Kona region has performed scientific Oceanography operations at eight stations.  These stations form two transects (areas) with one being offshore and one being close to shore. As of July 5th, there have been 9 CTD (temperature, depth and salinity) readings, 7 mid-water trawls (fish catches), over 15 acoustics (sound waves) recordings, and 30 hours of marine mammal (dolphins and whales) observations.

The University of Hawaii Ocean Sea Glider has been recording its data also.The acoustics data matches the trawl data to tell us there was more mass (fish) in the close to shore area than the offshore area. And more mass in the northern area than the south. This is evidence that the acoustics system is accurate because what it showed on the computer matched what was actually caught in the net. The fish were separated by hand into categories: Myctophid fish and non-Myctophid fish, Crustaceans, and gelatinous (jelly-like) zooplankton.

Variety of Non-Myctophid Fish caught in the trawl

Variety of Non-Myctophid Fish caught in the trawl

The CTD data also shows that there are changes as you go north and closer to shore. One of the CTD water sample tests being done tells us the amount of phytoplankton (plant) in different areas. Phytoplankton creates energy by making chlorophyll and this chlorophyll is the base of the food chain. It is measured by looking at its fluorescence level. Myctophids eat phytoplankton, therefore, counting the amount of myctophids helps create a picture of how the ecosystem is working.

The data showed us more Chlorophyll levels in the closer to shore northern areas . Phytoplankton creates energy using photosynthesis (Photo = light, synthesis  = put together) and is the base of the food chain. Chlorophyll-a is an important pigment in photosynthesis and is common to all phytoplankton. If we can measure the amount of chlorophyll-a in the water we can understand how much phytoplankton is there. We measure chlorophyll-a by using fluorescence, which sends out light of one “color” to phytoplankton, which then send back light of a different color to our fluorometer (sensor used to measure fluorescence). Myctophids eat zooplankton, which in turn eat phytoplankton. Therefore, counting the amount of myctophids helps create a picture of how the ecosystem is working.   The data showed us more chlorophyll-a levels in the closer to shore northern areas.

Bringing in the catch

The Sea Glider SG513 has transmitted data for 27 dives so far, and will continue to take samples until October when it will be picked up and returned to UH.

Overall the mammal observations spotted 3 Striped dolphins, 1 Bottlenose dolphin, and 3 Pigmy killer whales.  Two biopsy “skin” samples were collected from the Bottlenose dolphins. A main part of their research, however, is done with photos. They have so far collected over 900 pictures.

Looking at all the results so far, we see that there is an area close to shore in the northern region of Kona that has a higher concentration of marine life.  The question now is why?

We are now heading south to evaluate another region so that we can get a picture of the whole Eastern coastline.

Personal Log

In the driver's seat

In the driver's seat

Krill

Krill

And on deck the next morning we found all kinds of krill, a type of crustacean. Krill are an important part of the food chain that feed directly on phytoplankton. Larger marine animals feed on krill including whales. It was a fun process finding new types of fish and trying to identify them.Last night I found a beautiful orange and white trumpet fish. We also saw many transparent (see-through) fish with some having bright silver and gold sections. There were transparent crabs, all sizes of squid, and small clear eels. One fish I saw looked like it had a zipper along the bottom of it, so I called it a “zipperfish”. A live Pigmy shark was in the net, so they put it in a bucket of water for everyone to see. These types don’t ever get very big, less than a foot long.

I have really enjoyed living on this ship, and it will be sad to leave. Everyone treated me like I was part of the group. I have learned so much about NOAA and the ecosystem of the Kona coastline which will make my lessons more interesting this year. Maybe the students won’t be bored!

Sunrise over Kona Region

Sunrise

Sunrise

Heather Haberman: Plankton, July 9, 2011 (post #3)

NOAA Teacher at Sea
Heather Haberman

Onboard NOAA Ship Oregon II
July 5 — 17, 2011


Mission:  Groundfish Survey
Geographical Location:  Northern Gulf of Mexico
Date:  Saturday, July 09, 2011

Weather Data from  NOAA Ship Tracker
Air Temperature:  30.4 C   (86.7 F)
Water Temperature: 29.6 C   (85.3 F)
Relative Humidity: 72%
Wind Speed: 6.69 knots   (7.7 mph)

Preface:  Scroll down the page if you would like to read my blog in chronological order.  If you have any questions leave them for me at the end of the post.

Science and Technology Log

Topic of the Day:  Plankton, the most important organisms on the planet.

Say the word plankton to a class full of students and most of them will probably think of a small one-eyed cartoon character.  In actuality plankton are some of the most important organisms on our planet.  Why would I so confidently make such a bold statement?  Because without plankton, we wouldn’t be here, nor would any other organism that requires oxygen for life’s processes.

Plankton are a vital part of the carbon and oxygen cycles.  They are excellent indicators of water quality and are the base of the marine food web, providing a source of food and energy for most of the ocean’s ecosystem’s.  Most plankton are categorized as either phytoplankton or zooplankton.

Question:  Can you identify which group of plankton are the plants and which are the animals based on the prefix’s?

Simple marine food web. Image: NOAA

Phyto comes from a Greek word meaning “plant” while planktos means “to wander”.  Phytoplankton are single-celled plants which are an essential component of the marine food web.  Plants are producers meaning they use light energy from the sun, and nutrients from their surroundings, to photosynthesize and grow rather than having to eat like animals, which are consumers.   Thus producers allow “new” energy to enter into an ecosystem which is passed on through a food chain.

Because phytoplankton photosynthesize, they also play an important role in regulating the amount of carbon dioxide in our atmosphere while providing oxygen for us to breathe.  Scientists believe that the oceans currently absorb between 30%-50% of the carbon dioxide that enters into our atmosphere.

Did you know:  It is estimated that marine plants, including phytoplankton, are responsible for 70-80% of the oxygen we have in our atmosphere.  Land plants are only responsible for 20-30%.

Diatoms are one of the most common forms of phytoplankton. Photo: NOAA

Question:  Since phytoplankton rely on sun and nutrients for their energy, where would you expect to find them in greater concentrations, near the coast or far out at sea?

Red and orange indicate high concentrations of phyoplankton. Concentrations decrease as you go down the color spectrum. Image from NASA's SeaWiFS mission

Notice the greatest concentration of phytoplankton occur near coastal areas.  This is because they rely on nutrients such as nitrogen and phosphorus for their survival.  These nutrients are transferred to the sea as rains wash them from our land into the rivers and the rivers empty the nutrients into the sea.  We’ll address the problems this is causing in my next blog.

Did you know:  The ocean is salty because over millions of years rains and rivers have washed over the rocks, which contain sodium chloride (salt), and carried it to the sea.

It is easy to identify water that’s rich in phytoplankton and nutrients because the water is green due to the chlorophyll pigment plankton contain.  The further away from the nutrient source you get, the bluer the water becomes because of the decrease in the phytoplankton population.

This tool is called a Forel/Ule scale. It is used to obtain an approximate measurement of surface water color. This helps researchers determine the abundance of life in the water.

Let’s go up a step in the marine food web and talk about zooplankton.  Zoo is Greek for animal.  Most zooplankton are grazers that depend on phytoplankton as a food source.  I’ve learned that larval marine life such as fish, invertebrates and crustaceans are classified as zooplankton until they start to get their adult coloration.  After hatching from their eggs marine larva are clear and “jelly like” which is an adaptation that helps them avoid being eaten by predators.  Camouflage is their only line of defense in this stage of development.

A zooplankton sample we collected aboard the Oregon II using a neuston net. Notice the small juvenile fish and all of the clear "jelly like" larva.

When plankton samples are collected two different methods are used.  One method uses a neuston net which skims the surface of the water for 10 minutes.  See the video below to watch a sample being collected.

I am securing the neuston net to the metal frame by lacing it with a line (rope for all of you land lovers)..

The second method is using the bongo nets which are deployed at a 45 degree angle until they are a meter shy of the ocean floor, then they are brought back up.  This method collects samples from the vertical water column rather than just the surface.  The samples we collect with the bongo net look much different from the samples we collect with the neuston net.  Bongo samples are filled with more larva and less juveniles.

Bongo nets getting ready to be lowered into the water column. They are called bongo nets because they resemble bongos. Photo: SEFSC

Plankton surveys are done in an effort to learn more about the abundance and location of the early life stages of fish and invertebrates.  All of the samples we collect are preserved at sea and are then sent to the Sea Fisheries Institute in Poland.  This is where all of the identification of fish larva and other zooplankton takes place.  This information is then used by researchers to study things such as environmental quality requirements for larva, mortality rates, population trends, development rates and larval diets.

On the right is the "cod end", or plankton collection chamber, which attaches to the end of the nets. We then sieve the contents of the cod end and funnel it into a jar along with some preservative.

Personal Log:

My last log mentioned bycatch as one of the bad things about bottom trawling.  Another problem associated with bottom trawling is the destruction of habitats as the net and “doors” sweep along the ocean floor.  So far we have had two nets tear as a result of this collection method.  It’s a good thing they keep ten extra nets onboard as back ups!

Here are some of the extra nets that are kept on deck.

Aside from the nets tearing off there has also been a problem with the wire that deploys the net.  It has been twisting which prevents the “doors” from opening the net wide enough for a good sample collection.  The crew has tried extending all of the wire off of the reel in an effort to untwist it.  It seems to be working well, but we still need to keep a close eye on it.

I have also had the opportunity to be the hottest I have ever been in my entire life.  We had an abandon ship drill where everyone had to get into their immersion suits.  Picture yourself in the Gulf of Mexico, standing on a black deck, in the middle of the day, in July, while putting on a full body jump suit made of neoprene.  Hopefully we won’t have to use them at any point during the cruise.

Obed Fulcar, July 24, 2010

NOAA Teacher at Sea Obed Fulcar
NOAA Ship Oscar Dyson
July 27, 2010 – August 8, 2010

Mission:Summer Pollock survey III
Geograpical Area:Bering Sea, Alaska
Date: July 24, 2010

Science & Technology Log:
Thursday, July 22: After a night of swinging and swaying from the waves at high seas, I am somewhat used to it already. Today is the start of my new shift from 0400 in the morning until 4:00 pm in the afternoon, 12 hours on, 12 hours off. Since yesterday we left the continental shelf and we are heading to deeper waters. There was a scheduled trawl to be done early this morning, but the Acoustic Lab reported no fish at all on the screens. As part of the survey it is necessary to perform a CTD launch every morning at sunrise. CTD stands for Conductivity, Temperature, and Depth, explained Darin Jones, one of the young scientists in charge of the Pollock survey.
CTD

CTD

The CTD unit is made up of a series of bottles used to collect water samples at different depths, and also includes remote sensors to collect data such as sea temperature, salinity, depth, water pressure, and fluorescence. Fluorescence is the presence of Chlorophyll in the water which depends on the amount of sunlight that penetrates the ocean, indicating the presence of Phytoplankton (algae and other microscopic plants). They rely on sunlight to produce the energy that zooplankton growth is dependent upon. Zooplankton is the foundation of the Bering Sea food chain,since is made up of krill, small shrimp like crustaceans that are the primary source of food for commercial fish such as Pollock, Cod, Salmon, and pretty much any other fish in the North Pacific Ocean.
CTD

CTD

As the CTD is dropped the ship needs to stop in order lower the unit, which is attached by cables to an A-Frame crane, including one to transmit data. The CTD can only be used to depths of 600 meters, so another device called the XBT for Expendable Bathy-Thermograph (for depth and temperature) is used for depths up to 700 meters. It can also be launched manually while the ship is in motion, and data is transmitted through a thin copper wire that splits, hence the name “Expendable”. Once the CTD is hauled back onto deck, the water bottles are drained and samples taken for dissolved oxygen (DO)analysis. DO is sequestered using chemicals that react with the oxygen taking a solid form that preserves it for lab analysis.
XBT

XBT

Personal Log:
Last night I took motion sickness pills to keep me from getting seasick. After breakfast weather got really bad, with waves up to 6 feet, battering the Oscar Dyson. These conditions, combined with a heavy breakfast, made feel really dizzy, and next I know I was throwing up. My roommate, Vince Welton, who is also the ship’s tech guy, got me some very tasty saltine crackers, and medication, that help me feel better. I laid down on my bunk bed and doze off while listening to some Jazz by Michel Camilo.
While trying to rest the waves were crashing into the hull of the ship with a loud noise, while the ship kept going up and down. I was thinking about how seafarers of the past and the conditions aboard were so much different than today. Ocean going trips now are made much easier by the technology and modern amenities commonly found on board. Staterooms with bath, galleys or kitchens fully equipped with fridge, microwave oven, and entertainment rooms with flat TVs and DVD players are the norm. I kept thinking that the next 2 weeks on board the Oscar Dyson will be a lot like space travel, will all the walking up and down stairs from deck to deck, closing of hatches, and not been able to step outside the ship for a walk until reaching port.
The connection I can make about the CTD is that it reminds me a lot of the citizen science data collection and water quality monitoring I conduct with my students after school on the Harlem River, as part of “A Day in the Life of the Hudson River” a yearly event sponsored by NYSDEC (NY State Dept of environmental Conservation) and Columbia University Lamont-Doherty Laboratory. just like in the CTD we collect samples of water from the river to test for Dissolved Oxygen, Chlorophyll, PH, Salinity, Nitrates, plus soil samples from the mudflats.
When we collect the chlorophyll samples we use the same methods just as it’s done on the Oscar Dyson, squirting the water through a circular paper filter until it turns brownish. I am planning a lesson for next school year called “NOAA in the Classroom:Student CTD Activity” where using a student water sampling bottle my Environmental Science Club class will collect water from the Harlem River at different depths with the help of our wooden boat “Boca Chica” built after school. We test the samples for DO, Salinity, PH and other protocols using a LaMotte water quality test kit to monitor the health of the Harlem/Hudson River Estuary. This data will be reported to the GLOBE.gov Program website to be used by scientists and schools all over the world. My middle schoolMS319 is a GLOBE Program partner school, and also we will be reporting data from our new Wireless Weather Station. I strongly believe that students learn science by doing science!
Boca Chica

Boca Chica

“Navegando en Alta Mar”
Jueves, 22 de Julio: Hoy comence my primera guardia de las 0400 am a las 4pm. Desde que zarpamos del puerto de Dutch Harbor hacia aguas profundas me habia librado del mareo, pero finalmente me agarro.
El mal tiempo de hoy temprano, con violetas olas que golpeaban la nave de hasta 18 metros, mas un desayuno muy pesado me provocaron unas nauseas que termine en mi camarote vomitando y tirado en la cama. Despues de tomarme una medicina y de comerme unas galletitas de soda, me tome una siesta y me levante mucho mejor. El Sonar Acustico de la nave no detecto presencia de peces por lo que fui a ver el lanzamiento de un CTD o unidad de Conductividad y Profundidad Termal. El CTD contiene botellas para recoger muestras de agua y sensores para medir la temperatura y salinidad del mar hasta 600 metros.
Para medidas mas profundas de hasta 700 metros se usa una unidad manual desechable llamada XBT. Ambas unidades son usadas para obtener datos cientificos como el nivel de Oxygeno disuelto, Salinidad, Profundidad, y Florescencia (nivel de clorofila), la ultima es muy importante pues refleja la abundancia de algas microscopicas de las que depende elZooplankton. El zooplankton esta compuesto de minusculos crustaceos que son la base del ecosistema alimenticio del Estrecho de Bering, del cual dependen especies comerciales como el Bacallao, Salmon y Arenque, asi como casi toda especie de pez en el Oceano Pacifico Norte. El uso del CTD es muy parecido al trabajo que hago con mis estudiantes analizando las aguas del Rio Harlem. Estos jovenes cientificos tambien toman muestras de agua y practican analisis de campo para Oxygeno disuelto, PH, Nitratos, Salinidad e incluso pruebas de Clorofila, como parte de un evento anual llamado “Un dia en la Vida del Rio Hudson” .
En este evento organizado por el Laboratotio Lamont-Doherty de la Universidad Columbia, y el Depto de Conservacion del Estado de NY, participan escuelas a todo lo largo del Rio Hudson, recaudando datos cientificos sobre el rio. Pensamos usar a “BOCA CHICA”,un bote de madera que armamos de tarde, para una practica de CTD tomando muestras de agua del rio, analizarlas, y reportar los datos en el internet. Tambien mis estudiantes de la Escuela Intermedia Maria Teresa Mirabal Ms319, de origen dominicano en su mayoria, aprenden ciencia ambiental al tomar datos de la Estacion Metereologica ubicada en el techo de la escuela. Ellos reportan los datos via internet en la pagina web del Programa GLOBE.gov, para ser usados por cientificos y estudiantes por todo el mundo.