Melina Vella: “Spot” the Difference, September 16, 2026

NOAA Teacher at Sea

Melina Vella

Aboard NOAA Ship Henry B. Bigelow

September 10 – 30, 2026

Mission: Northeast Fisheries Science Center Bottom Trawl Survey – Leg 1

Geographic Area of Cruise: Northeast Atlantic U.S. Coast

Date: September 16, 2026

Weather Data from the Bridge

Latitude: 35º06’30.5927”N 

Longitude: 075º14’04.2990”W

Wind: Northwest wind at 10 knots 

Air Temperature: 25.2ºC (77.3ºF)

Science and Technology Log

Let me set the scene of an average tow for you. A conveyor belt of flopping fish (and others) moving at a rate of, what I estimate, sometimes hundreds of fish a minute. Practiced hands are moving with precision and speed to pick out dozens of fish and place them into their respective buckets. Oh–also–the ship is reorienting itself towards the next survey station so there’s a fair bit of unpredictable jostling. Gushing water sloshes around inches deep on the floor. The sensory experience is unlike any I’ve experienced before.

close-up view of a pile of fish on a nondiscernable surface. Most of the fish are one of two small, similar species, both silvery with yellow pectoral fins. in the foreground is a horseshoe crab; two other horseshoe crabs, lying amid the fish at odd angles, appear toward the back of the photo.
Quick–what species do you see?? I spy a couple horseshoe crabs, croaker, and some spot…

It’s overwhelming, but also such a thrill. I’d describe it as a similar experience as one of those blind boxes you can get at your local toy store. Just like the outside of the box has pictures of the types of toys you’ll get, we have a fairly good idea about what species to expect. But, there’s always the chance you might pull a never-been-seen-before fish.

Melina, wearing orange overalls and large blue latex gloves, grins as she holds up a small skate (type of fish similar to a ray) for a photo. she is in the wet lab.
Holding a small Clearnose Skate (Raja eglanteria), one of my favorite skates that I see often in the Delaware Bay!

For the first few days, it felt like everyone was speaking in code, especially when it came to the names of some of the animals we were catching. I’d never heard the words “Loligo” or “Illex” in my whole life. Eventually, though, I figured out that those terms translated to “squid,” and that’s as far as I’ve gotten.

five small squid laid out at random on an electronic measuring board. they are not yet arranged straight against the measurement line. the largest may be 20 centimeters.

Squid lined up on the fish measuring board. 

I’ve put together this brief list of must-know species that we commonly encounter that are frequently mistaken for one another. Maybe by the end of the trip I’ll be able to tell them apart…

Squid: Illex & Loligo

There are quite a few types of squid we could come across during our survey, to include Shortfin (Illex illecebrosus) and Longfin Squid (Doryteuthis pealeii). Illex have shorter triangular fins than the rounded longer fins of a Loligo. The skin of a Loligo will slough off more easily. Coloration also varies between the two squid, with Illex more of an orange-brown and Loligo leaning purple and pink.

scientific illustration of a shortfin squid
Illex are also called Shortfin or Summer Squid (NOAA Fisheries).
scientific illustration of a longfin inshore squid
Loligo are also called Longfin Inshore Squid, Winter Squid, and Boston Squid. They have had multiple scientific names, some of which include the Loligo genus (NOAA Fisheries).
close-up photo of a small squid against a blue background; its triangular fins are extended
An Illex specimen showing off its triangular fins (Photo by Fisheries and Oceans Canada via WoRMS).
close-up view of a pile of small squid on an electronic measuring board - these are only 6 to 8 centimeters
A pile of small Loligo (which we endearingly nickname “small-igo”) on the fish measuring board before processing.

Spot & Atlantic Croaker

You’d think this one would be intuitive for me, considering this Spot (Leiostomus xanthurus) and Croaker (Micropogonias undulatus) are the two of the fish we catch the most during our seining programs at the Nature Center, but unfortunately not. The most helpful tip is that a spot will have, well, a spot! 

close-up image of a spot against a white background
Spot have a more slender body and rounded snout (North Carolina Department of Environmental Quality).
close-up photo of an Atlantic croaker against a gray background
Atlantic Croakers have much more heft to them, as well as a slight protruding point to their caudal fin, or tail (Florida Museum photo by Zachary Randall).

However, especially when dozens of them are flopping vigorously and moving on a conveyor belt, that tiny spot can be hard to find. The area on a croaker where the pectoral fin meets the body can also be dark and round (not unlike a spot’s spot…).

Four-Spot, Ocellated, Windowpane, & Summer Flounder

I’ve always been fond of flatfish. They’re such a funky shape (and typically quite delicious as well). At the Nature Center, we had an adorable Summer Flounder named June.

a fish tank. small laminated cards line the top outer edge of the tank - they contain photos and names of the species in the tank. we can see a small flatfish on the front pane of glass, aligned with its tail pointing upward and its face toward the sand.
June the Summer Flounder pressed against the tank vertically. 

We’ve come across plenty of flatfish during this cruise. The main ones that I have the most trouble telling apart are the Fourspot (Hippoglossina oblonga), Ocellated (Ancylopsetta quadrocellata), Windowpane (Scophthalmus aquosus), and Summer Flounder (Paralichthys dentatus). All four of these species are left-eyed flatfish, meaning that if you placed the fish with the mouth oriented upwards below the eyes, they would be on the left side of the fish.

scientific illustration of a peacock flounder
A Peacock Flounder (Bothus lunatus) is a left-eyed flatfish found in tropical and subtropical areas of the Atlantic Ocean (Animal Diversity Web).
close-up view of a very circular, very stripey flatfish in a white bucket of water. its tail is like a small circle attached to a large one.
We caught a very distinct right-eyed flatfish, the Naked Sole (Gymnachirus nudus). 

So, the eyed-ness (that’s not a word but you know what I mean) is not gonna help you much with differentiating this quartet of resemblant fish; you’ll have to zoom in and take a closer look at their unique features. 

A Fourspot Flounder will have four very distinct eye-like dark spots, called ocelli. They are situated in pairs with one pair closer towards the tail and the other in the middle of the body. Of course, it’s not just the fourspot flounder that will have four spots. 

The Ocellated Flounder will also have four large ocelli, but they will be distributed across the body differently. Three of an Ocellated Flounder’s spots will be in a triangle shape towards the right half of the body and the last spot above the pectoral fin.

photo of an ocellated flounder against sand; we can see the four large spots
Ocellated Flounder (Ancylopsetta quadrocellata) (Smithsonian Tropical Research Institute)

Lastly, the Windowpane and Summer Flounders are going to have smaller spots scattered along their bodies. Windowpane Flounder are named for their thin, near-transparent bodies. They are more rounded than the other similar oval-shaped flounders. Windowpane Flounders have many small dark spots. In contrast, Summer Flounders typically have five larger prominent ocelli towards the tail-end of the body. Summer Flounder can reach up to forty inches, whereas windowpane tend to max out around about half that.  Another helpful diagnostic feature is that the dorsal (upper) fin of a Windowpane Flounder will have fringed rays towards the front, almost like little hairs.

close-up photo of a windowpane flounder on a white background
Windowpane Flounder (Scophthalmus aquosus)
(Smithsonian Environmental Research Center)
close-up photo of a summer flounder on a white background
Summer Flounder (Paralichthys dentatus)
(Smithsonian Environmental Research Center)

Aw, Shucks

I’ve been lucky to have some of the freshest seafood I’ve ever encountered over the past week. The whole mission is an indescribable undertaking, and one of the ways those onboard are rewarded is through being able to eat our catch.

It’s truly a group effort with every team having a hand in the process in some way. The deck crew is pulling up the giant hauls while coordinating with the bridge. The engineers are scurrying around fixing things before anyone even notices they need repairing. 

The science team is measuring and processing. The team estimated this tow to be over 3,000 pounds, with the overwhelming majority of the haul Atlantic Sea Scallops (Placopecten magellanicus). 

view of a large bin on deck full of hundreds of scallops. toward the back of the bin, a crewmember with a blue hard hat, rain gear, and life vest reaches an arm into bin. we can see a portion of the net in the background. it is nighttime.
The day watch team was rewarded with a very scallop-y tow (Photo Credit: NOAA SST Ben Tuttle).

Throughout my time on the ship I’ve learned not only a lot of technical science, but also picked up some skills I never knew I’d learn onboard. If you need someone to shuck about a hundred scallops with minimal precision but a lot of enthusiasm, I’m your girl. I’m also not afraid to get my hands dirty (or rather, inky) and prep dozens of Loligo for some fresh calamari.

baskets of scallops
A couple baskets of fresh scallops set aside from the big scallop tow.
buckets of shucked scallops on a sorting table near a measuring board
Shucked scallops being rinsed and bagged.
close-up view of a bowl of scallop pasta
The final product: a fabulous pasta with seared scallops.


We shucked enough scallops to fill a couple plastic bags and handed them off to the galley crew, who whipped up a delicious scallop pasta for lunch the next day.

Personal Log: The Pros and Cons of Night Watch

Pro: Talk about a golden hour!! You’re rewarded halfway through your shift with a sunrise view unlike any you can see on land. The flying bridge gives breathtaking views from all directions.

view of sunrise over the ocean, seen from an outside deck and also through the bridge windows
Looking through the bridge windows from the deck outside.
a tower with satellite instruments, painted red, stands out in the light of the sunrise
A glamour shot of some of the ship’s external instruments.

Cons: My meals are all outta wack! I’m truly a creature of habit–on land I alternate pretty consistently through my go-to breakfast foods of apple cinnamon oatmeal or Lucky Charms. However, when your breakfast is at 11 p.m., what’s the move? Should I be eating the meal the Steward Department saved for me from a few hours before while I was fast asleep, or do I adhere to strict traditional breakfast foods?

Did You Know?

Did you know that some people can’t visualize anything in their mind? It’s estimated that about 1% of people experience a lack of visual imagery, also called aphantasia. Unfortunately for me and my species identification abilities, I fall into this 1%. On the other hand, many of my science team members can mentally call up an image of a fish with such precise colors and details that they basically turn into a walking field guide. 

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