Month: September 2024

Trawling for sand lance at the Revolution offshore wind field

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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.

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

sunset-windmill
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.

Box-trawl
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

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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.

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

Ammodytes-americanus---Rankin-Lab---21AUG2
American sand lance swimming in our tank at Rankin Lab on 21 August 2024