NOAA Teacher at Sea
Aboard NOAA Ship Reuben Lasker
May 29 – June 7, 2019
Mission: Rockfish Recruitment & Ecosystem Assessment
Geographic Area: Central California Coast
Date: June 2-7, 2019
June 2, 2019 Game Plan and Trawling Line: 5 hauls in the Piedras Blancas Line near San Simeon, CA. Piedras Blancas is known for its Northern elephant seal colony, M. angustirostris. Hauls were conducted outside of the marine reserve and we did not encounter seals.
Catch Highlights: The night started off with excitement when Keith Sakuma brought in an Pacific electric ray, Torpedo californica, and we all got to see it up close before releasing.
In Haul 3 we collected a pelagic octopus, Ocythoe tuberculata, shown below. Chromatophores in cephalapods, including squid, cuttlefish and octopus, are complex organs made up of both muscle and nerve and provide the ability for the animal to rapidly change its skin color in order to blend into the surrounding environment to avoid predation, communicate, or send a warning signal. It was impressive to watch the chromatophores at work as the pelagic octopus attempted to blend into the white background of his tank by turning white (see photos below) We released it back to the sea.
The differences in skin coloration of the five primary squid species we are catching including Boreal Squid, Blacktip Squid, Unknown Squid, Gonadus Squid, and Market Squid (see image below) are noteworthy. While living market squid exhibit brown, pink and purple skin color (see image below) the Chiroteuthis squid tentacle displays orange and red chromatophores (see image below).
In Haul 4 we collected a Cranchia scabra, which Chief Scientist Keith Sakuma calls the “baseball squid” or glass squid whose body is covered with tubercles (brown spots on mantle in photo below). This animal attempted to hide from us by turning white, retracting its tentacles and inflating himself into a ball, somewhat resembling a baseball. After a few pictures, we released it back to the sea.
Another exciting deep-sea creature, the Pacific hatchet fish, Argyropelecus affinis, was collected in a bongo net deployed prior to CTD, for Dr. Kelly Goodwin’s eDNA research. The fish we collected below still has intact blue scales due to being well preserved in the bongo. The hatchet fish lives in mesopelagic zone down to 2000 m depths where the CTD sensors recorded a temperature of four degrees Celsius! Hatchet fish have upward facing eyes and mouths and swim up to the the epi-pelagic zone at night to feed on salps and krill.
Kelly conducted a quick surface bucket dip prior to CTD deployment in which we found a small (~2 inch) siphonophore, which I was very excited about since this was my first one to ever see in person! Siphonophores are colonial Cnidarians composed of individual animals called zooids. Moss Landing Graduate Student Kristin Saksa and I were able to confirm the identification of this beautiful creature as a siphonophore using an invertebrate field guide that Keith Sakuma brought on board. Perhaps due to the temperature change from being in the sea to being observed in a cell culture dish under the microscope, the siphonophore broke apart into its individual zooids right in front of my eyes. See before and after photos below.
Tonight I was also able to observe living salps that were pulled up in the bongo net and take a video. It was neat to see the salps pulsing.
Haul 5 was a massive haul full of pyrosomes, Pyrosoma atlanticum. Kristin Saksa volunteered to stir the bucket of pyrosomes (using her arms) so that we could obtain an accurate distribution of organisms for the initial volume count and analysis. As I video of this event (see stills from the video below), we were all laughing and realized that Kristin may be the only human on Earth who has ever stirred pyrosomes.
In haul 5 we were surprised to find a Giant 7-armed Atlantic octopus, or blob octopus. Keith Sakuma explained that the males have 7 arms as the fifth is a sex appendage whereas the female has 8 arms. After photographing this beautiful deep-sea octopus, we released him back to the sea.
June 3, 2019 Game Plan and Trawling Line: 5 hauls Outside Monterey Bay
Catch Highlights: Two of the hauls produced a lot of krill. The hauls had a high species density with a lot of myctophids, salps and blue lanternfish. Such hauls are time consuming to sort so as not to overlook something new and small. In one of the hauls we found a new-to-me myctophid called Nanobrachium. I dissected some of the fish and found that CA lanternfish and Northern anchovies were full of eggs, and their age/reproductive status was previously unknown.
We caught 2 young ocean sunfish, Mola mola. Both were immediately returned to the sea.
We found several species of deep sea dragonfish which we arrayed below on a ruler. Most of these fish are less than 6 inches long, no bigger than a pencil, but they are equipped with sharp fangs and are apex predators in their realm! Dragonfish have large bioluminescent photophore organs underneath their eyes (and sometimes lining their bodies) which produce light and are used to attract or deter prey and attract mates.
We collected a stoplight loosejaw, Malacosteus niger, which can unhinge its jaw in order to consume large prey.
June 4th: Davenport Line
The highlight of today was at 5:45 P.M. when team red hats went to the flying bridge for our workout and to hang out with Ornithologist Brian Hoover. There was a lot of Humpback whale activity. I counted around 20 spouts. We observed one whale that flapped its tail against the sea surface around 45 times in a row, perhaps communicating to nearby whales by generating pulses in the water or creating a visual cue. We saw several full breaches. We finished up the Davenport Line at 6:00 AM as the sea became rough. Thanks goodness for handrails in the shower.
June 5th: Outside of Tomales Bay
I woke up at 4PM and headed to the galley for dinner at 5PM. The boat was rocking so much that I became dizzy and knew that I would become sick if I tried to eat dinner, so I headed straight back to bed. Around 9PM the sea seemed to have calmed a bit, but I soon learned that it only felt calmer because the ship was traveling in the same direction as the swell at the moment but that we were about to turn around. Due to the rough conditions, the first haul inshore at Tomales Bay was delayed until midnight so the fish sorting team decided to watch “Mary Poppins Returns” in the galley. The talented chefs of the Reuben Lasker made the most amazing almond cookies today and, thankfully, temped me to eat again.
Catch Highlights: Haul 1 at station 165 was one of the easiest and most exciting catches of the survey so far because we collected a lot of jellyfish – my favorite! We counted 66 West Coast sea nettles, Chrysora fuscescens, seven Northern anchovies (7) and 24 market squid. I actually have a tattoo of West Coast sea nettle on my ankle. We placed the jellyfish flat on the lab bench and quickly measured their bell diameter before returning them to the sea. They did not sting us as most of the nematocysts were likely triggered during haul in. I removed a rhopalia, a sensory structure that lines the margin of the bell of Syphozoans (the “true” jellyfish). West Coast sea nettles have eight rhopalium which house the the ocelli (light sensing organ) and statolith (gravity sensing organ). A photomicrograph I took of the rhopalia under the dissecting microscope is below.
Haul 2 mostly consisted of Northern anchovies, 1 krill, a few moon jellyfish, Aurelia aurita, a few squid, which made for another very short and easy sort (see photo below). I study moon jellyfish in my lab back at McCallie High School, so I was curious to look inside of the stomach and reproductive organs of these wild jellyfish. Under the dissecting microscope, eggs were present and were purple in color (see photomicrograph below).
Haul 3 had a lot of krill, young of year (YOY) Pacific hake, Merluccius productus, one large hake, and a few market squid. This sort was also super easy except for separating the small YOY Pacific hake from the krill.
June 6th: Outside Farallones. On our final night, we conducted three hauls with very small harvests consisting of few organisms and low species density. One new to me fish in the final catch was a top smelt fish (see image below). These were the three easiest sorts of the survey. It was suggested by Keith Sakuma that the catches were small due to the stormy conditions.
June 7, 2019: Return to San Francisco