Downriver from New Orleans, behind heavy doors in grass-covered bunkers that stored artillery during World War II, are millions of dead fish.
They're in rows of glass jars, each one a time capsule, a specimen pulled from a particular place on a particular day, labeled so future scientists can return to the exact moment it was collected. Together, these jars form the Royal D. Suttkus Fish Collection, a kind of morbidย library of the Gulfโs fish life.ย
โItโs the worldโs largest collection of post-larval preserved fishes,โ said Brian Sidlauskas, the director of the Tulane University Biological Diversity Institute, or TUBRI, and the curator of the fish collection. โWeโre getting ready to add another 3 million specimens.โย
Curator of the Royal D. Suttkus Fish Collection and director of the Tulane University Biodiversity Research Institute, Brian Sidlauskas holds a sturgeon in Belle Chasse on Wednesday, Dec. 17, 2025. (Staff photo by Brett Duke, The Times-Picayune)
STAFF PHOTO BY BRETT DUKE
At a moment when many research institutions are losing funding, shrinking storage and closing collections, Tulane is expanding this one.ย Scientists say these โlibrariesโ of preserved animals have become more valuable in an era of rapid environmental change.ย
โIf a scientist, 100 years from now, wants to access a particular fish,โ Sidlauskas said, โitโll be there for them to check out of the library.โย
Justin Mann, manager of the Royal D. Suttkus Fish Collection, holds a preserved monkfish at the Tulane University Biodiversity Research Institute in Belle Chasse on Wednesday, Dec. 17, 2025. (Staff photo by Brett Duke, The Times-Picayune)
STAFF PHOTO BY BRETT DUKE
The Suttkus collection holds more than 8 million fish specimens, the vast majority of which were acquired by the collectionโs founder, ichthyologist Royal D. Suttkus, who, over the course of a nearly six-decade career, amassed over 7 million fish in jars. The collection will soon grow by 3 million specimens fromย the University of ถถา๕h at Monroe, which is shuttering its fish collection. They're even getting a CT scanner, so researchers can digitize the anatomy of thousands of fish.
And the collection has just taken on another extraordinary addition: About 1,000 rare deep-sea fish specimens from the Gulf of Mexicoโs โmidnight zone.โย
Fish specimens collected by the DEEPEND Consortium for Tulaneโs Royal D. Suttkus fish collection. (Paula Burch-Celentano/Tulane University)
The new fish were submitted to the collection by the DEEPEND Consortium, an initiative funded in part by Deepwater Horizon oil spill settlement funds and housed at Nova Southeastern University in Florida, which plans to send many more specimens to Tulaneโs bunkers.
โWe probably know more about the dark side of the moon than we know about these fishes,โ said Melanie Stiassny, the curator of fishes at the American Museum of Natural History in New York City.ย
Justin Mann, manager of the Royal D. Suttkus Fish Collection, holds preserved fish specimens that will be added to the collection at the Tulane University Biodiversity Research Institute in Belle Chasse on Wednesday, Dec. 17, 2025. (Staff photo by Brett Duke, The Times-Picayune)
STAFF PHOTO BY BRETT DUKE
The midnight zone, intact
In the deepwater Gulf, sunlight fades fast. Pressure rises to punishing levels. Itโs cold. And life there is adapted to an environment that most humans never see.
That's part of what makes deep-sea fishes hard to study. Even collecting them isnโt easy. Pressure and temperature changes that affect a fishโs body on a trip to the waterโs surface from thousands of feet below can essentially turn deep-sea fish to mush.ย
Paddlefish are seen in a jar in the Royal D. Suttkus Fish Collection at the Tulane University Biodiversity Research Institute in Belle Chasse on Wednesday, Dec. 17, 2025. (Staff photo by Brett Duke, The Times-Picayune)
STAFF PHOTO BY BRETT DUKE
DEEPEND has learned how to avoid that. Their specimens are remarkably well preserved, Stiassny said. โWe have deep-sea fish specimens and they donโt look as good as this,โ she said.
โThe main thing is keeping everything cold,โ said Tracey Sutton, DEEPENDโs director. His team will chill seawater before they bring fish up. And they raise their nets very, very slowly so the pressure changes gradually.ย
Among the fish Sutton has given to Tulane are anglerfishes, deep-sea predators with needlelike teeth that hunt using a bioluminescent lure โ a glowing bulb that extends from their head to attract prey in the darkness.
Curator of the Royal D. Suttkus Fish Collection and director of the Tulane University Biodiversity Research Institute, Brian Sidlauskas stands among shelves of preserved fish specimens in Belle Chasse on Wednesday, Dec. 17, 2025. (Staff photo by Brett Duke, The Times-Picayune)
STAFF PHOTO BY BRETT DUKE
There are lanternfish, too, a family of sardine-like deep-sea fish, which, like anglerfish, also glow in the dark. But lanternfish do so in order to camouflage, using bioluminescence to mimic the rays of light that filter into the depths, erasing their silhouettes so predators canโt pick them out.ย
Some of these specimens are so rarely seen that identifying them correctly is a challenge. Or scientists find, when they look at a fish more closely, that what they thought was five species turns out to be just one strange creature that changes radically over the course of its life cycle.ย
Curator of the Royal D. Suttkus Fish Collection and director of the Tulane University Biodiversity Research Institute, Brian Sidlauskas examines preserved fish specimens in a jar in Belle Chasse on Wednesday, Dec. 17, 2025. (Staff photo by Brett Duke, The Times-Picayune)
STAFF PHOTO BY BRETT DUKE
โThat's really common with crustaceans,โ Sutton said. โWe work on pelagic shrimps a lot, and often their larvae look like monsters.โ
Those uncertainties are why physical specimens are so valuable. A DNA sequence can be incomplete, or a photo can be misleading. But a preserved fish, reliably stored on a shelf, can always be rechecked, reanalyzed and reinterpreted as science advances.ย
An anglerfish, photographed on a DEEPEND Consortium research expedition. (Photo by Dantรฉ Fenolio)
โPicklinโ plants, trappinโ ratsโ
Suttkus became known not only for what he studied, but how relentlessly he collected. Most fish collectors go out looking for a particular species. If they pull up a common fish, they might throw it back. Not Suttkus. He kept everything. โThat makes the collection an incredible resource, because itโs a time capsule,โ Sidlauskas said.ย
Minnows are seen in a jar among shelves of fish specimens in the Royal D. Suttkus Fish Collection at the Tulane University Biodiversity Research Institute in Belle Chasse on Wednesday, Dec. 17, 2025. (Staff photo by Brett Duke, The Times-Picayune)
STAFF PHOTO BY BRETT DUKE
Whatโs stored in Tulaneโs bunkers is a snapshot of every fish Suttkus found in a particular stream on a particular day. Heโd cast his net and collect in the same spot over and over again, so the changes in fish populations before and after certain environmental watershed events โ like the damming of the Red River, or the implementation of the Clean Water Act โ are visible in the collection.ย
His relentless collecting did seem to earn Suttkus a kind of oddball folk-hero status. He , called โThe Collecting Machine,โ written by a colleague. One verse goes like this: โNot a thing that swims or crawls or flies, is safe from this odd man.โ / Heโs picklinโ plants, trappinโ rats, and digginโ up old bones. / Heโs grabbinโ up putrid roadkill, then takinโ it all back home.โย
A pair of argyropelecus aculeatus, or lovely hatchetfish, photographed on a DEEPEND Consortium pelagic research trip. (Photo by Dantรฉ Fenolio)
But ichthyologists today are thrilled to have a resource as complete as the Suttkus collection. Other institutions, including the Stiassnyโs American Museum of Natural History, have more species of fish in their collections than Tulane does, but Suttkus is responsible for the sheer number of specimens in his collection, the largest in the world.
The density of data points in the collection allows researchers to ask questions like: How common was a certain species in a certain creek? When did decline begin? What might have caused it?
In that sense, thereโs a kind of parallel between the work Suttkus did and the work Sutton is now doing. Just as Suttkus went back to the same sites over and over again, so now is Sutton.ย
Deep-sea expeditions like the ones DEEPEND does are expensive, but through a combination of federal grants and Deepwater Horizon oil spill funding, โweโve been able to look at the long-term trends in deep pelagic life in the Gulf.โ In the last 15 years, theyโve done 14 cruises to collect fish specimens. There are few, if any, other efforts like DEEPEND worldwide, Stiassny said.
A lionfish is seen in a jar in the Royal D. Suttkus Fish Collection at the Tulane University Biodiversity Research Institute in Belle Chasse on Wednesday, Dec. 17, 2025. (Staff photo by Brett Duke, The Times-Picayune)
STAFF PHOTO BY BRETT DUKE
The collection can feel spooky. It is, after all, a vast collection of pickled dead animals. But its value to conservation is impossible to measure. You canโt protect what you canโt identify. And in a warming Gulf where change is accelerating faster than scientists can track, the jars in Tulaneโs bunkers may become the most complete record of what once lived offshore.
โWeโre changing global habitats so markedly that itโs these museum collections that tell us what weโre losing,โ Stiassny said.