Tag: Phronima

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Dorothy Holley: Basking Sharks, Great Shearwaters, and Phronima Amphipods, Oh My! August 9, 2025

NOAA Teacher at Sea

Dorothy Holley

Aboard NOAA Ship Pisces

July 31 – August 15, 2025

Mission: Northeast Ecosystem Monitoring Survey (EcoMon)

Geographic Area of Cruise: Northwest Atlantic Ocean

Date: August 9, 2025

Weather Data from Bridge:
Latitude: 4118.447 N
Longitude: 06649.365 W
Relative Wind speed: 17
Wind Direction: 314
Air Temperature: 18.8
Sea Surface Temperature: 18.979
Barometric Pressure: 1022.28
Speed Over Ground: 8.7
Water Conductivity: 4.348
Water Salinity: 32.04

closer view of a great shearwater in flight, as seen from above. we can make out the dark head, white throat, patterned back. the water is rippled blue and white.
a great shearwater, visible only as a silhouette, swoops low over calm waters reflecting an orange sunset
a great shearwater swoops low over calm blue waters
side view of great shearwater in flight; we can see its white underside well. it flies above calm waters reflecting a blue and pink sunset.

Photos of Great Shearwaters in flight by Cameron Cox, NOAA Seabird and Marine Wildlife Observer

First, A blog-reader texted me to say that it looked like I was having fun! Yes, while NOTHING could be more fun than your birthday party, Teacher-At-Sea is at the top of the list of fun teacher-things to do! I hope that ALL teachers, especially those from North Carolina, will apply to be a NOAA Teacher at Sea as we continue to grow strong STEM ecosystems while helping our communities make informed decisions.  Thanks for reading Elaine!

Second, an answer to last BLOG’s math problem: If 1 knot = 1.15 mph, and the ship is traveling 8 knots, a stop 15 miles away will take us a little over 1 and a half hours (about 1.6 hours) to reach.

a woman sits in an observation chair on the flying bridge
Allison Black, NOAA Seabird and Marine Wildlife Observer

Science at Sea

Animal monitoring is an active part of our floating weather station. A dolphin sighting texted through WhatsApp brings lots of off duty folks up to see. The NOAA Corps on the bridge keep a constant vigil to make sure we don’t hit a whale. But the “Seabird and Marine Mammal Observers” are a functional part of our Science team. They spend their daylight hours on the Flying Bridge scanning the horizon and recording their findings. The species, group size, and photos are catalogued and stored for long term monitoring. This data can be used to estimate bird and mammal abundance in the Northwest Atlantic Ocean now as well as set baseline data through AMAPPS (Atlantic Marine Assessment Program for Protected Species). NOAA Scientists are conducting surveys and developing abundance and distribution models to better understand how protected species such as whales, dolphins, and sea turtles use our waters. (Read more here)

illustration of a NOAA vessel in the ocean; nearby are silhouettes of birds in flight and marine mammals swimming
Diagram of an observer on the flying bridge a NOAA ship looking for seabirds and marine mammals.
Credit: Su Kim, NOAA Fisheries

Career Spotlight

Cameron Cox has been able to turn his love of birdwatching into a career. As a Seabird and Marine Mammal Observer Scientist on NOAA Ship Pisces, he can be found on the Flying Bridge during the daylight hours.

portrait of a man wearing a baseball cap, sunglasses, banana around nectk, sitting at a wooden table on the deck of NOAA Ship Oregon II. a closed laptop and a fancy camera sit on the table.
Cameron Cox, NOAA Seabird and Marine Wildlife Observer

Cameron’s passion for birding kinda snuck up on him. He remembers hiking with a neighborhood friend who had started birdwatching for a hobby. At age 13, Cameron was hooked. Since he was homeschooled, Cameron was able to carve out time to pursue this new interest. He spent his 20’s traveling around the United States looking at birds. He had a 2-thousand-dollar car and 6-thousand dollars worth of optics – binoculars, camera, and spotting scope.  

Cameron explained to me that the long term monitoring projects are hard for Universities and non government organization (NGOs) to fund, which is why our NOAA work is so valuable. The data sets are free and readily available to everyone. Unfortunately, when the BP Deepwater Horizon oil spill decimated the Gulf Coast, there wasn’t baseline data available for recovery and accountability. He was able to assist in creating possible baseline data by performing Seabird and Marine Observations off the coast of Florida, a similar ecosystem.

These days, Cameron leads birdwatching tours in what he calls “Environmental Entertainment.” He loves watching others connect with the importance of the natural world, and hopes to help them become conservationists. Cameron has also published two books, Terns of North American: a Photographic Guide, and a Peterson Reference Guide to Seawatching: Eastern Waterbirds in Flight, co-written with Ken Behrens. Writing at the rate of one book a decade, his ongoing projects will ensure he has a long life! This is Cameron’s first time being a Seabird and Marine Mammal observer with NOAA. We hope it is not his last!

the silhouette of a bird banks low above the water, reflecting a firey sunset
Wilson’s Storm Petrel. Photo by Cameron Cox.

Interesting Things: The Seabird and Marine Mammal Scientist Observers onboard are monitoring lots of animals specifically, but there are other animals we are studying or just find in our nets.

top down view of a blue crab resting in a white bucket containing a couple inches of water
a blue crab rests in the corner of a large red bin, filled with a few inches of water

Engineer Drew found this crab in our sea strainers (they strain the water used around the engines). ET Alex named her Crustacina (spelt like crustacean, but pronounced like Cristina). We will keep her on-board until we can get to more shallow waters for release.

NOAA Scientists are collaborating with a group in Miami to study ocean acidification on pteropods’ shells. The phronima amphipod (see video below) inspired the movie alien. They commandeer a salp, eat the flesh, and then lay eggs in the empty pouch.    

Phronima amphipod (left) and salp pouch (right)
For 50 years….. Basking Shark Videoed by ENS Keene-Connole
close-up view of a small fish on a petri dish
microscope set up, with petri dishes and pipettes nearby
a phronima amphipod in a petri dish

A microscope is always ready to check out the latest find!

Personal Log

Have you heard of or participated in the Christmas Bird Count (CBC)? Started in 1900 by 27 dedicated birders, this GOAT Citizen Science Project provides long term data sets that help conservation biologists of all forms study long term bird health and guide conservation actions. The CBC is one example of how good can win (Side Hunt, no link will be provided). Consider joining a Christmas Bird Count this year to learn more about Citizen Science and the importance of long term data sets (see CBC ).

You do the Math: The First Christmas Bird Count was held December 25, 1900. If 18,500 individual birds representing 89 different species were logged by the 27 participants, how many different birds were seen (on average) by each person? Check in the next blog post for the answer.

a line of styrofoam birds - all the same base shape, but decorated with marker to resemble specific species, including a puffin and a cardinal - sitting on a tabletop.
These styrofoam birdies are going to be a science experiment of their own…. stay tuned!

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Katie Gavenus, Bonus Blog: MIXOTROPHS, May 5, 2019

NOAA Teacher at Sea

Katie Gavenus

Aboard R/V Tiglax

April 26 – May 9, 2019

Mission: Northern Gulf of Alaska Long-Term Ecological Research project

Geographic Area of Cruise: Northern Gulf of Alaska – currently in transit from ‘Seward Line’ to ‘Kodiak Line’

Date: May 5, 2019

Weather Data from the Bridge

Time: 2305
Latitude: 57o 34.6915’
Longitude: 150o 06.9789’
Wind: 18 knots, South
Seas: 4-6 feet
Air Temperature: 46oF (8oC)
Air pressure: 1004 millibars
Cloudy, light rain

 

Science and Technology Log

I was going to just fold the information about mixotrophs into the phytoplankton blog, but this is so interesting it deserves its own separate blog!

On land, there are plants that photosynthesize to make their own food. These are called autotrophs – self-feeding.  And there are animals that feed on other organisms for food – these are called heterotrophs – other-feeding.  In the ocean, the same is generally assumed.  Phytoplankton, algae, and sea grasses are considered autotrophs because they photosynthesize.  Zooplankton, fish, birds, marine mammals, and benthic invertebrates are considered heterotrophs because they feed on photosynthetic organisms or other heterotrophs.  They cannot make their own food.  But it turns out that the line between phytoplankton and zooplankton is blurry and porous.  It is in this nebulous area that mixotrophs take the stage!

Mixotrophs are organisms that can both photosynthesize and feed on other organisms.  There are two main strategies that lead to mixotrophy.  Some organisms, such as species of dinoflagellate called Ceratium, are inherently photosynthetic.  They have their own chloroplasts and use them to make sugars.  But, when conditions make photosynthesis less favorable or feeding more advantageous, these Ceratium will prey on ciliates and/or bacteria.  Bacteria are phosphorous, nitrogen, and iron rich so it is beneficial for Ceratium to feed on them at least occasionally. Microscopy work makes it possible to see the vacuole filled with food inside the photosynthetic Ceratium. 

illustration of mixotrophic dinoflagellate Ceratium
I created this drawing after viewing a number of microscopy photos of the mixotrophic dinoflagellate Ceratium under different lights and stains. This artistic rendition combines those different views to show the outside structure of the dinoflagellate as well as the nucleus, food vacuole and chloroplasts. (Drawing by Katie Gavenus)

Other organisms, including many ciliates, were long known to be heterotrophic.  They feed on other organisms, and it is particularly common for them to eat phytoplankton and especially cryptophyte algae. Recent research has revealed, however, that many ciliates will retain rather than digest the chloroplasts from the phytoplankton they’ve eaten and use them to photosynthesize for their own benefit. Viewing these mixotrophs under blue light with a microscope causes the retained chloroplasts to fluoresce.  I saw photos of them and they are just packed with chloroplasts!

illustration of mixotrophic ciliate Tontonia sp.
The mixotrophic ciliate Tontonia sp. eats phytoplankton but retains the chloroplasts from their food in order to photosynthesize on their own! I made this drawing based off of photos, showing both the outside structure of the Tontonia and how the chloroplasts fluoresce as red when viewed with blue light. (Drawing by Katie Gavenus)

Mixotrophs are an important part of the Gulf of Alaska ecosystem.  They may even help to explain how a modestly productive ecosystem (in terms of phytoplankton) can support highly productive upper trophic levels. Mixotrophy can increase the efficiency of energy transfer through the trophic levels, so more of the energy from primary productivity supports the growth and reproduction of upper trophic levels. They also may increase the resiliency of the ecosystem, since these organisms can adjust to variability in light, nutrients, and phytoplankton availability by focusing more on photosynthesis or more on finding prey. Yet little is known about mixotrophs.  Only about one quarter of the important mixotroph species in the Gulf of Alaska have been studied in any way, shape or form!

Researchers are trying to determine what kinds of phytoplankton the mixotrophic ciliates and dinoflagellates are retaining chloroplasts from.  They are also curious whether this varies by location, season or year.  Understanding the conditions in which mixotrophic organisms derive energy from photosynthesis and the conditions in which they choose to feed is another area of research focus, especially because it has important ramifications for carbon and nutrient cycling and productivity across trophic levels.  And it is all very fascinating!

food web illustration
A drawing illustrating a fascinating, tightly linked portion of the Gulf of Alaska food web. Mesodinium rubrum must eat cryptophyte algae (this is called obligate feeding). The Mesodinium rubrum retain the chloroplasts from the cryptophyte algae, using them to supplement their own diet through photosynthesis. In turn, Dinophysis sp. must feed on Mesodinium rubrum. And the Dinophysis retain the chloroplasts from the Mesodinium that originally were from cryptophyte algae! (Drawing by Katie Gavenus)

Did you know?

Well over half of the oxygen on earth comes from photosynthetic organisms in the ocean.  So next time you take a breath, remember to thank phytoplankton, algae, and marine plants!

Personal Log:

Tonight was likely our last full night of work, as we expect rough seas and high winds will roll in around midnight tomorrow and persist until the afternoon before we head back to Seward.  We were able to get bongo net sampling completed at 6 stations along the Kodiak Line, and hope that in the next two nights we can get 2-4 stations done before the weather closes in on us and 2-4 nets on the last evening as we head back to Seward.

Despite our push to get 6 stations finished tonight, we took time to look more closely at one of the samples we pulled up.  It contained a squid as well as a really cool parasitic amphipod called Phronima that lives inside of a gelatinous type of zooplankton called doliolids.  Check out the photos and videos below for a glimpse of these awesome creatures (I couldn’t figure out how to mute the audio, but I would recommend doing that for a less distracting video experience).

 

 

Phronima
A parasitic Phronima amphipod. This animal typically lives inside doliolids, a type of gelatinous zooplankton. Apparently its body structure and fierce claw-like appendages inspired the design of “Predator.”