I am an oceanographer, with a focus on biogeochemsitry and plankton ecology. Plankton are microscopic movers and shakers in the ocean. Phytoplankton (plant plankton that can photosynthesize) convert the sun’s energy, along with nutrients such as carbon and nitrogen, into consumable food for zooplankton (animal plankton that eat phytoplankton or other zooplankton); zooplankton can then be eaten by fish, molluscs, and even whales, thus entraining the energy of the sun into a rich and complex marine food web. This network of living things in the ocean impacts not only seafood economies and nutrition available to sea creatures, but also global nutrient cycles.
I use ecological theory, lab experiments, at-sea observation, data synthesis and computer modeling to study ocean food web dynamics, and how changes in the environment impact the network of marine life. It is important to me that my work contributes to the greater good of the Earth: humankind and whole ecosystems – plants, animals and biogeochemical functions – included. Whether this is done through education, policy, or contributing to the understanding of how this beautiful planet works, my ultimate goal is to provide knowledge and services that equip our society to live well and in harmony as part of the Earth System.
NEWS & UPDATES
EXPORTS is at it again!
13 May 2021
NASA EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) is at it again. This time the team has set sail from Southampton, on the southern coast of England, and is sampling at a long-term oceanographic time series site called the Porcupine Abyssal Plain station. The goal is to replicate the sampling and studies done in 2018 in the Northeast Pacific Ocean, in order to have a contrasting location and time of year to the data collected in summer 2018. The data collected on the first cruise represent the ocean carbon cycle during a low-productivity, low-export time, while data collected on the current cruise will represent the opposite: carbon cycling during a high-productivity, high-export time. The North Atlantic in spring is famous for it's huge phytoplankton bloom, but it is also famous for stormy, windy conditions. So, let's keep our fingers crossed that the team can collect all the samples and information they set out to, without getting too seasick! Learn more about EXPORTS here!
Below is an image of the zooplankton and micronekton (bigger stuff) collected in a net tow to 1000 m depth; photo by Dr. Amy Maas
Mixotrophs & Mixotrophy
02 February 2021
I am excited to announce a new scientific working group, sponsored by the Ocean Carbon and Biogeochemistry program, which I helped co-organized! It is called Mixotrophs and Mixotrophy (M&M for short). Mixotrophs are aquatic planktonic organisms that can photosynthesize, gaining energy from the sun like a plant, but they can also eat other organisms. Examples of this on land are rare, but carnivorous plants like venus flytraps are one. In the ocean, mixotrophs are common, but hard to study. This new working group is going to focus on identifying gaps in knowledge and the methods needed to answer those questions. Mixotrophs impact the flow of energy at the base of the marine food web, and may play a role in the resilience of our oceans to climate change.
For more details, click here!
INSPIRATION AT THE OCEAN CARBON AND BIOGEOCHEMSITRY SUMMER WORKSHOP
28 June 2019
I have dedicated this spring and summer to processing and analyzing the samples and data that we collected on the NASA EXPORTS field expedition to the North Pacific Ocean. This entails lots of time in the lab, at the microscope, and at my computer, pouring over spreadsheets. It is easy to get lost in all the preserved zooplankton and numbers, easy to forget that there are nearly 100 other scientists, working on their own datasets, all in preparation to bring our findings together in a grand understanding of the ocean's carbon cycle - an essential part of the entire Earth System! Fortunately, there have been two workshops - one in Williamsburg, Virginia, and one in Woods Hole, Massachusetts - where I had the chance to meet with other scientists and discuss our progress, findings and challenges. The workshop in Woods Hole is convened every year by the National Science Foundation's program: Ocean Carbon and Biogeochemistry, or OCB. It was inspiring to learn what others are working on; it reminded me that while individual scientists produce knowledge in small increments, as a community, we are finding answers to some tough questions, and ultimately working toward a healthy future for people and the planet.
Click the photo below to watch my presentation:
LINKS BETWEEN CLIMATE CHANGE, CARBON AND ZOOPLANKTON POOP
13 FEBRUARY 2019
It's hard to believe, but tiny zooplankton play an important role in the Earth's carbon cycle, and impact where and how carbon dioxide is stored in the ocean. In fact, carbon that zooplankton are responsible for moving from the surface ocean to deeper waters is on the same order of magnitude as the amount of carbon that humans emit as carbon dioxide each year! Some colleagues from Denmark and I did a modeling study to find out whether zooplankton-mediated carbon has changed over the past 50 years. We modeled zooplankton grazing (eating), egestion (pooping) and respiration (breathing), and found that indeed, these pathways for carbon flux have decreased in much of the North Atlantic Ocean over past decades. We also found that in some places it has actually increased, all due to changes in the ocean environment and distributions of zooplankton species. Please click below to learn more about our study, published in Nature Ecology and Evolution.
Below is an image of a copepod (a type of zooplankton) with its prey.
Photo credit: Erik Selander
DANCING THROUGH DECK OPS ON NASA EXPORTS CRUISE
07 September 2018
Deck operations aboard research vessels are carefully coordinated dances, involving the bridge (where the captain and mates steer the vessel), winch operators, ship technicians, scientists and their equipment. A lot can go wrong: equipment can be damaged or lost, samples can be scrambled, and people can get hurt. Aboard the R/V Roger Revelle EXPORTS cruise this autumn, numerous complicated maneuvers were performed. A successful deployment and recovery of our last MOCNESS plankton net tow of the cruise was worth dancing for joy.
THE HJORT SUMMER SCHOOL, TRAITS CONFERENCE AND THE HANSEATIC LEAGUE IN NORWAY
11-23 August 2017
This August I attended the Hjort Summer School, at the Espegrend Marine Biological Station in Bergen, Norway. The course focused on connecting experimental and modeling techniques. The Hjort summer school program was named after Johan Hjort, a Norwegian fisheries scientist. The fishing industry plays a huge role in Norwegian history. I visited the Hanseatic League (13th-15th century) museum, in a restored fish merchant's building on the Bergen waterfront. Cod was the basis of an economy that made fish merchants rich and powerful. It is fitting to see a dried cod next to a portrait of Hansa nobility (below). While in Bergen, I also attended the 3rd International Workshop on Trait-Based Approaches to Ocean Life.
Fifth Trait-Based Approaches to Ocean Life Workshop
24 January 2022
Imagine that you are trying to describe all of ocean life to someone. Would you go organism by organism, telling them about every single species individually, with each little nuance from size to shape to color to behavior to life cycle? Or would you start to group organisms by particular habits, or shapes, or roles that they play in the ocean food web? The latter way of describing ocean critters is sometimes called a "trait-based" approach, because it lumps organisms together based on traits relevant to a topic or question. There is an ongoing debate over when such lumping loses important details that matter to understanding an ecosystem, and when it is a more effective way to analyze and understand ocean life. The Trait-Based Approaches to Ocean Life workshop brings together modelers, experimentalists, and observationalists from all over the world, to present and discuss their work using the trait-based approach. This year it will be held in Knoxville, Tennessee USA, from January 24-27.
Image courtesy of the Traits Workshop, D. Talmy
DATA, DATA, DATA!
07 January 2020
Happy New Year! Data is a big deal these days. In fact, an expert on the radio told me this morning that data is now one of the biggest businesses in the world! Data itself is magical because it is just numbers, zeros and ones, pure information. But, it can be transformed into useful facts, reveal unknown truths, and can also be twisted for malignant purposes. Understanding how to interpret data and data treatments is key to being able to spot conclusions supported by cherry-picked data, falsified information, or incorrectly analyzed data. Equally important, however, is access to data. Over the last few months, scientists like myself have been working hard to finalize their datasets collected during the 2018 NASA EXPORTS research cruise, and make them available to the public. It is the public, after all, who really own these data. Federal agencies such as NASA and the National Science Foundation have open-access repositories where all data produced during research supported by tax dollars must be made available after a certain amount of time - usually within a couple years. Even if you aren't interested in dealing with raw data, there are lots of tutorials out there to assist in interpreting scientific graphs and information. I encourage you to get informed so that you can draw your own conclusions about the world!
MAINE FISHERMEN AND CLIMATE CHANGE - A LIVELY DISCUSSION
27 FEBRUARY 2019
All of us feel the effects of climate change in one way or another, but fishermen are out on the ocean far more regularly than most scientists, and are in a unique position to discuss the impacts of climate change on their livelihoods and lifestyles. I was honored to be an invited science speaker at the Island Institute's Fisherman's Climate Roundtable meeting. The meeting has been convening annually for 13 years! The discussion was mainly focused on bait, since most lobstermen in Maine use herring to catch the tasty crustaceans, and herring catch was just slashed by ~80% in an effort to preserve the stock. Fisheries scientists think that young herring are not surviving and entering the stock as new recruits, raising an alarm for fisheries managers. My talk focused on the copepod Calanus finmarchicus, an important food source for both herring and right whales. Warming temperatures in the Gulf of Maine are impacting Calanus and the animals that depend on them. Please stay tuned for an exciting new study poised to come out, explaining the link between temperature, Calanus and changes in the critically endangered North Atlantic right whale population.
Photo below from the Portland Press Herald's Ben McCanna
SAMPLE PROCESSING AND PUBLICITY IN BERMUDA
30 October 2018
Now that we have returned from the NASA EXPORTS research cruise in the NE Pacific, our group has a lot of samples to process in the lab. One measurement that we are after is total community respiration - in other words, an estimate of how much carbon dioxide the whole zooplankton community exhales per day at Ocean Station Papa, where we were working. I joined lead researcher Dr. Amy Maas and her associate Dr. Andrea Miccoli for a week of lab work at the Bermuda Institute for Ocean Sciences (BIOS). While there, a nice piece was published about all of our EXPORTS work.
SEATTLE MOBILIZATION FOR NASA EXPORTS EXPEDITION IN THE NE PACIFIC
10 August 2018
I am in Seattle, where we are mobilizing for the first NASA EXPORTS research cruise into the Subarctic Northeast Pacific Ocean. There will be two ships out there: the R/V Roger Revelle (ship to the right in image below) and the R/V Sally Ride (ship to the left). Mobilization is an exciting time - equipment is loaded, the ships are fueled, inspected and prepared, and you get to see all the food you will eat over the next month as it is loaded and stored. The NASA EXPORTS project is a substantial research program aimed at measuring the ocean's biological carbon pump.
UMAINE INTERVIEW ABOUT MY NSF GRADUATE RESEARCH FELLOWSHIP WORK ON ZOOPLANKTON AND CARBON
15 August 2016
Last week I was interviewed for UMaine Today, the University’s video magazine. It was a good opportunity to share my work on the role of living organisms in the ocean’s biological carbon cycle, as well as discuss why the Gulf of Maine is a “living laboratory” in the face of climate change.
(Also, I officially graduated!)