Field work

Beachseining at night. In a snowstorm. For sandlance.

10 December 2024. Emma and Hannes just returned from another trip to Wells Harbor in Maine, where we had been sampling and monitoring a local population of American sand lance (Ammodytes americanus) over the late summer and into fall. This was definitely a trip for the history books. Not because of the sand lance, mind you (we caught a total of 7), and certainly not for the beauty of the scenery either. We had hoped to catch these fish close to the begin of their spawning season (which starts around December) at low tide in the harbor, reasoning that our chances would be better at night. What we hadn't in mind was the snow storm that began walloping coastal Maine just as we arrived at the site. But what's a (slightly nutty) biologist to do? We gritted our teeth, hoped for the waders not to leak and braved the elements ...

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On the night of December 9th, 2024, Emma stands on the docks of Wells Harbor - incredulous of the idea to go beach seining ...

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Snow falls on the Christmas "tree" of Wells Harbor

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The forecast was off by a few degrees ... and a lot of snow

Luckily, we were able to find a bed and a warm shower afterwards in the Alheim Commons of the Wells NERR. On the morning after, we walked into a frosty winter land, still somewhat incredulous that we actually went beachseining the night before. We believe that the drop in temperature has made the fish move to slightly deeper water that are not accessible via beachseine anymore. We learned something. Did we? But that's how science - sometimes - works.

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On the morning of December 10th, 2024, the beach seine stands in front of the Alheim Commons dorms of the Wells NERR.

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Snow dusts the lobster cages at Wells Harbor

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We found out that sand lance do not like the coldness of the Wells Harbor much either

Fishery Bulletin publishes black sea bass diet metabarcoding study

22 November 2024. We are happy to share that our paper on black sea bass stomach content metabarcoding has been published today in the traditional NOAA journal Fishery Bulletin. Our study used black sea bass juveniles caught in Mumford Cove to study their diet via a molecular approach known as metabarcoding. This method often detects rare or soft-bodied prey better than traditional morphological content analyses. We found that small, newly settled black sea bass eat mostly shrimp, but also many softbodied polychaetes. And weirdly, they seem to like one particular kind of (invasive) amphipod. Only larger juveniles seem to add fish to their diet.

Our study is a great first collaboration between our departments genomic experts (Ann Bucklin, Paola Batta-Lona) and the Evolutionary Fish Ecology Lab. The first product of our collaborative efforts has seen the light!

Fishery Bulletin is the 143 years old peer-reviewed journal managed and published by the National Marine Fisheries Service (NMFS) of the National Ocean and Atmospheric Administration (NOAA). It publishes Open Access at no costs to authors. Click the link below to download the paper.



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Composition of prey detected in samples from stomachs of juvenile black sea bass (Centropristis striata), collected in Mumford Cove off Connecticut in August 2020, through metabarcoding with (A) the mitochondrial cytochrome c oxidase subunit I (COI) gene region and (B) the V9 hypervariable region of 18S rRNA. Bars represent the total number of COI and V9 gene sequences identified for each of 6 and 10 major prey taxa in DNA samples from 35 and 99 stomachs, respectively. In panel A, lists / pictures of the major prey species and their relative proportions for each prey taxon are provided (modified after Figure 1 in Batta-Lona et al. 2025)

Trawling for sand lance at the Revolution offshore wind field

6 September 2024. During the first research cruise of the CIEROW group on board the R/V Connecticut, our lab deployed a box trawl in- and outside the Revolution Wind field for a total of 7 times and 5 different locations. The box trawl had a 6 mm cod-end and tickler chains to catch small benthic fish – specifically sand lance of the genus Ammodytes.

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Research crew on CRW09-24 (fltr: Xavier Warren, Hannes Baumann, Evan Ward, Jessica Vorse, Michael Whitney, Bridget Holohan, Michael Cappola, Paola Batta-Lona)

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On 4 September, the sun sets at the Revolution wind field, still under construction

The box trawl was deployed from the main deck winch of the R/V Connecticut, with approximately 200m of wire let out in stations with water depths ranging from 34 – 38m, trawl speeds of 2 – 2.5kn for 13-15 upon reaching full wire-out lengths. Total trawl time (trawl in water – out of water) was about 25 minutes. During light hours, the trawl was equipped with a GoPro (Hero 4) to obtain footage of the trawled seafloor and potential organisms.

Overall, the trawl worked well with the ship and deployed as intended over the bottom. The GoPro footage revealed mostly sandy/muddy substrates with surprisingly little benthic fish life. Sand lance were neither caught in the trawl nor seen on the videos. Most trawls caught only few organisms, with the exception of Trawl 3 at station R6, which collected a number of common benthic fishes such as two hake species, one skate, sea robin and scup.

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The box trawl stands on the deck of the R/V Connecticut

Compilation-specimen-pics
Fish species caught at Trawl 03 at station R6 on 4th September 2024 (9:30 PM): Northern (1) red hake (Urophycis chuss), (2) thorny skate (Leucoraja erinacea), (3) silver hake (Merluccius bilinearis), (4) red hake juvenile, (5) butterfish (Peprilus triacanthus), (6) scup (Stenotomus chrysops), (7) Northern sea robin (Prionotus carolinus). Gridded background has 5 mm squares.

For this first deployment, we were cautious operating the gear in safe areas, but probably ended up trawling over sandy/muddy sediments that are not good habitat for sand lance. For the next cruise, we will therefore aim to alter trawl locations to include stations with known gravel or coarser sediment types.

A special thanks to Joel Llopiz and Lyndsey Lefebvre from Woods Hole Oceanographic Institution, who kindly lent us the box trawl to fish for sand lance, and to Justin Suca for facilitating this. We are also grateful to Marco, Sam, John and Luke from the R/V Connecticut crew for helping to deploy this new gear, even in somewhat rougher seas.

Fishing for inshore sand lance in Maine

20 August 2024. Emma and Hannes went on a road trip through New England to again visit our good friends and colleagues at the National Estuarine Research Reserve (NERR) in Wells, ME, Jeremy Miller and Jason Goldstein. Our mission this time was to try - for the first time - to find and collect American sand lance (Ammodytes americanus), the congener species to the Northern sand lance (A. dubius), which our lab has been investigating for now more than 7 years.

While the Northern sand lance can be reliably found on Stellwagen Bank in the southern Gulf of Maine, the specific whereabouts and promising collection sites for A. americanus are new, uncharted territory for us. They are often referred to as the inshore sand lance species, but where exactly would be a good spot to collect them?

On this late August week, we followed a tip from Jeremy from the Wells NERR to look at the harbor, where he had seen large schools near the docks all through summer.

After a good amount of scouting and trial (and error!) we ultimately got lucky at dead low tide, where we were able to use the beach seine to catch more than a thousand  sand lance adults and eventually succeeded in transporting ~ 300 of them back to the Rankin Lab for further learning how to rear and keep them.

This was the first of a handful of upcoming trips, where we plan to catch sand lance closer and closer to the begin of their spawning season at the end of November.

We hope that the luck stays with us during the next trips.

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The harbor of Wells, ME, on the afternoon of August 19th 2024

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American sand lance swimming in our tank at Rankin Lab on 21 August 2024

A Day on the Ocean

20 May 2024. Who wouldn't want to trade the confines of a highschool classroom for a day on the ocean, particularly one packed with whales, dolphins and seabirds? On this Monday in May, 60 seniors of the Marine Magnet Highschool in Groton, CT and the Plainfield Highschool in Plainfield, CT were indeed lucky enough to enjoy such exceptional experience and a very special class out on the water.

Because this was no ordinary whale watch. Our team from the NSF-funded sand lance project (Hannes, Zosia, Lucas, and Emma) accompanied the highschoolers and together boarded the "Tails of the Sea" (Captain John Boats, Plymouth, MA). While the vessel navigated the route to the Stellwagen Bank National Marine Sanctuary, Zosia, Emma and Lucas assembled small groups of students to tell them more about what extraordinary fish sand lance are, why they are so important, and why ocean acidification may be a troublesome issue for these forage fish.

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On 20 May 2024, Emma Siegfried explains the importance of sandlance to highschool students

What we hoped but couldn't have known for sure: nature spectacularly cooperated with our curriculum. We observed large numbers of minke, fin, and humpback whales as well as a large pod of Atlantic white-sided dolphins chasing schools of sand lance all around the ship, while gannets, seagulls and terns were trying to get their share of the feast from above. Mesmerized, nobody could get away without learning the central lesson of this day. Sand lance are the backbone of the Stellwagen Bank National Marine Sanctuary, and there are still too many things we do not know about these fish.

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Lucas Jones introduces Stellwagen Bank to students of the Marine Magnet Highschool in Groton, CT

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Zosia teaching students from Plainfield Highschool about ocean acidification and potential impacts on the food web

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On May 20th 2024, students stand on the bow of the 'Tails of the Sea' to spot whales and dolphins

A special thanks for a flawless coordination and logistics to highschool teachers Amy Ferland from Groton, Stephanie Pye and Anita Japp (supporting this event despite her recent retirement) from Plainfield. This NSF-funded outreach activity will now be repeated for two more years! At least all our team can't wait to get out there again. Have a look at the days pictures and a video of some of the most memorable moments.

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Returning from a successful class two teachers from the Marine Magnet Highschool and UConn's Zosia Baumann

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Emma Siegfried, Lucas Jones, and Zosia Baumann

The new cod – WrackLines article on our Black Sea Bass research

28 May 2024. The latest issue of Wrack Lines, the in house magazine of Connecticut Sea Grant, just published a nice feature article about our recent and ongoing research on Black Sea Bass in Long Island Sound. Written by Paul Choiniere, the article explains the background and the research in an easy, accessible way, while introducing our lab and its main actors.

Have a read!
(downloads pdf)


Thenewcod-WrackLines2024

Max Zavell defends his PhD thesis!

 

18 April 2024. Today we are happy and proud to announce that Max Zavell has successfully defended his dissertation titled "Experimental assessment of ocean warming and acidification effects on multiple life stages of Black Sea Bass, Centropristis striata". A big, heartfelt congratulations from the entire lab!

Max Zavell had started as a PhD student in our lab in fall 2020, and his thesis research broke new ground by working experimentally with Black Sea Bass, a grouper species of great interest because of its recent, explosive increase in abundance in Long Island Sound and the larger northwest Atlantic shelf. Over two fall and winter seasons, Max conducted ambitious long-term rearing experiments on juveniles and adults to study how overwintering could be the key to understand these new dynamics. Now, after only three and a half years, Max has stepped up to the plate and showed his peers and colleagues the fruits of the work.

We were particularly delighted that all this committee members - Profs. Jacqueline Webb (URI), Catherine Matassa (UConn), and Eric Schultz (UConn) - were able to attend in person!

Well done, Max! Your team spirit and unwavering energy will be missed! We wish you all the best for your next career steps!

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On April 18th, Max begins presenting his PhD research at UConn's Department of Marine Sciences

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Done! Max and Hannes savor a moment of pride in the Rankin Lab

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Max Zavell and Matt Mouland, who were a great team in the Rankin Lab and beyond

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Max with Hannes and Prof. Jacqueline Webb from the University of Rhode Island

Hannes returns from Chile!

 

16 April 2024. After a 9-month sabbatical stay at the University of Concepcion in Chile, Hannes returned to US soil today, full of experiences, data, and a chest full of samples of larval, juvenile, and adult Chilean silversides. Grateful to the many helpful colleagues and friends, a first year of experiments are in the bag, resulting in a number of interesting findings that await further analysis and - crucially - a second, replicate experiment in the year to follow. In other words, while the sabbatical is now over - the project of revealing co- and countergradient variation in the Chilean silverside is still very much underway. On to the next chapter!

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The cove of Puda near Dichato to the north of Concepcion, Chile

New 2023 sand lance experiment under way!

 

By Lucas Jones.

November 26, 2023. Members of the Sand lance Mafia assembled onboard the F/V Miss Emily in hopes of finding spawning ripe fish for our 2023 experiment. After loading our gear, Captain Kevin navigated us towards the southwest corner of Stellwagen Bank and deployed our beam trawl for our first 10-minute tow.

Boom! From the first tow, fish in spawning condition were brought on board, counted and separated by sex. Now, we just needed to repeat this for 13 more trawls until we had a sufficient amount of fish to start the experiment. After collecting 40+ spawning ripe males and females, we headed back to port wile starting to strip-spawn. This is an all hands on deck process, where we need to work together to evaluate the fish in real time and use the most ripe fish available.

The successful strip-spawn event now marks the start of our most ambitious experiment to date, where DNA and RNA samples will help us further investigate potential mechanisms behind the sand lances high CO2 sensitivity.

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Blastula stage sand lance embryos ~ 24h post fertilization

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The sandlance 2023 team after the first trip to Stellwagen Bank this year (left to right: Sam, Emma Siegfried, Chris Murray, Lucas Jones, Zosia Baumann, David Wiley)

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On 26 November, Lucas is back at the Rankin Lab with the goods!

UConn Today reports on Hannes’ Chile research

This article has been reposted from UConn Today. Read the original here

October 12, 2023 | Elaina Hancock - UConn Communications

Snap Shot: How Will Organisms Adapt to Climate Change?

A UConn Marine Sciences researcher is spending time in Chile studying an important forage fish, and how this vital part of the food chain will adapt to a changing climate

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The rocky and picturesque shores of the Pacific near Dichato

The world’s oceans have experienced record heat in 2023. With rising temperatures and increasing acidification, we don’t yet know the full extent these changes will have on marine ecosystems.

UConn Department of Marine Sciences Associate Professor Hannes Baumann studies fish, including important forage fishes such as sand lance and silverside, to see how they adapt to changes in environmental conditions. Many species are already adapted to temperature gradients that exist across latitudes on Earth, and Baumann believes that from these patterns, we can learn how fish may adapt to climate change – in time. This so-called “Space-for-Time” approach is one tool scientists use to predict the long-term consequences of climate change.

As part of his post-doctoral work, Baumann experimentally found similar climate adaptation patterns in Atlantic and Pacific silversides. He suspects that a higher-order relationship exists between the strength of adaptation and the strength of the underlying climate gradient.

Now, with a grant from the National Science Foundation, Baumann has the opportunity to return to and expand his study of silversides to a South Pacific species and study how they are adapted to their coastal latitudinal temperature gradient.

“We are hoping the prove the validity of a principle of evolutionary adaptation for the Southern Hemisphere. It will then allow us to compare and integrate the patterns with the silverside species from the Northern Hemisphere, which evolutionary ecologists have been studying for decades already,” says Baumann.

After a two-week proof-of-concept trip to Chile in the Fall of 2022, Baumann established connections with local fishermen and colleagues at the Universidad de Concepcion in Dichato, Chile.

“To get spawning fish, we visit fish markets – called here caletas de pescadores – and first establish a connection to those who make a living catching silversides (“pejerrey del mar”). We’re making friends to explain our unusual request to accompany a fisherman during the night. This is the best method to make sure that the eggs get fully fertilized," he says.

In the Summer of 2023, Baumann began his yearlong sabbatical and has now moved to Chile for five months to begin the main experimental work on Chilean silversides, their adaptations, and the strength of those adaptations to underlying climate change.

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Hannes in Tongoy near Coquimbo/Chile