Programs Blog

Fishy Business

May 09, 2026

Lyra and Aiden working through the 30 myctophids caught on evening watch

Field Day (Saturday), May 9, 2026

Noon Position: (Lat and Long): 35 degrees 28.6’ N, 070 degrees 33.4’ W

Log (nm): 2685 nm

Weather / Wind / Sail Plan (from 1300 Watch Change): Wind: South by east force 6, 8ft swell, sail plan staysl’s and jib

Description of location: North Sargasso near the Gulf Stream

Myctophids, also known as lanternfish, are a family of fish that make up a majority of fish biomass in the ocean; we caught 30 of them last night, the largest being about the size of my pinky, and the smallest being the size of my pinky nail. My job on board is to look at these fish, and ID them down to species level. This takes a while. Throughout this cruise I have been haunting the lab at strange hours of the night, shoulders crunched, neck craning over the scope, meticulously IDing each strange migrator we get coming to the surface from the mesopelagic (also known as the ocean twilight zone). This work is critical to understanding pelagic population structures.

Now that all sounds quite fancy so to sum it up in what is actually said in the lab: I wake up at Fish Hour to look at some Guys and try to take photos of them while the boat is Rocking Quite A Lot, then to the celebration of at least me, and usually the rest of the lab I get to sing out my species ID with some fun name like Centy B (Centrobranchus nigroocellatus) or Glenn Cocco (Gonichthys cocco). The process has gotten a bit less formal as time has gone by. If I’m not the first one pushing for it to be less formal, I am at the very least the first to adopt it. One aspect of this job that I really love is taking what seems like such a big intimidating idea and breaking it down into simpler, more accessible parts. Rather than trying to put up more boundaries as educators on board we work to show everyone that DNA extractions are going to involve chopping up a fish and moving around a lot of soapy water. Being able to actually do the work helps break down those walls that keep someone from doing something they never thought they could.

Recently I have gotten the time to finally teach more of the students on board to do what I have been doing. Just today as I was hunched over the scope IDing fish Lyra popped into the lab; and just like that they were calling out Glenn Cocco and picking out diagnostic traits they had learned to differentiate the 240 odd species of myctophid. Being able to pass on what I have learned to someone new has always been the most rewarding part of this job for me, which is probably why I’m sailing as a teaching assistant, but every day I see a crew member on board doing the same thing. A few nights ago as I was working through a dozen myctophids to ID our 1^st marine tech Raechel looked over at me, and asked, “Did you ever think you were going to be spending so much of your life looking at plankton?” And myself, full of sleep in my eyes, and dazed a bit after a month of this still got to smile and say, “Yeah I think I did.”

I’m sure tonight in our Neuston tow we’ll get plenty more myctophids, that has been pretty much a guarantee this whole trip. As our time on board winds down, and we gear up for our final shore component in Woods Hole I look forward to: working with the students on their projects so we can help give meaning to the data we’ve collected out here, reflecting on our time as a community on board and what that has meant to all of us, and a really good breakfast sandwich from Coffee O with thick cut bacon.

P.S. Happy Birthday Conor! I don’t know what your plans are; hopefully Holly Hill is open by now. I’m sorry to say I will be hijacking your 30^th birthday message to also say happy birthday to Eoin, and Dad. Eoin, I can’t wait to talk about whatever questions you’ve had brewing up there. Dad, the Cramer Crew says hello and wants you as head steward if we sail to Ireland, I’ll co-stew as well. And a very big thank you to Mum who is going to read this first, and tell the others they’re in it, see you guys in Falmouth.

Aiden Houlihan, Fish Guy