Tiny fish called sand lances are showing up in abundance in Menemsha, and can be seen from the docks and the jetties. However, the high prevalence of these fish isn’t limited to Chilmark, according to Michael Armstrong, assistant director of the Massachusetts Division of Marine Fisheries.
“This year I’m hearing reports everywhere,” Armstrong said. “They’re just booming.”
On June 20, near the fuel dock in Menemsha, cormorants and stripers could be seen feeding on sand lance. The birds and the bass were in very close proximity to each other. At times they appeared to swim alongside each other in pursuit of sand lances. Armstrong was unsurprised by this.
In nature, if something is “superabundant,” Armstrong said, there’s not going to be a fight over that resource. “Competition only happens when things are in shortage.” In the instance of the bass and birds, as described to him, Armstrong said a wealth of sand lance means it’s a time to be “focused on eating,” and time to “ignore your neighbor.”
Armstrong described sand lances as an “incredibly important forage species” consumed by everything from stripers to tuna to whales.
“A lot of times when the whales are bubble feeding, the humpbacks, this is what they’re feeding on. It’s either sea herring or sand lance,” he said.
Armstrong said sand lance occupy the base of the marine food chain. “Stripers can’t get enough of them,” he said.
Stomach samples of stripers taken off Chatham a few years ago showed “it was nothing but sand lance that they were eating — it’s a very high-energy fish. It’s got a lot of oil.”
Asked how many a striper could eat, Armstrong said, “Oh boy, a big striper could have 100 in its stomach.”
Bass and whales, he said, often wind up pushing sand lance to the surface, where birds can reach them. “Everything eats them,” he said.
A paper published by University of Massachusetts Amherst researchers likened sand lance to pasta.
“Their shape makes them very attractive to many predators because they’re easy to swallow. Most marine predators don’t chew their food, rather they swallow their food whole. It’s like eating spaghetti instead of a meatball,” the paper’s lead author, Michelle Staudinger, wrote.
Armstrong said sand lance are plankton eaters that grow quickly, and don’t live long. In the recreational fishing community they are called sand eels. However, Armstrong said that’s a misnomer. “They’re not even close to being an eel, but they’ve got an eely kind of body,” he said.
There are two species off the Massachusetts coast, one inshore and one offshore. “They’re really hard to tell apart,” he said.
The sand part of the sand lance’s name, Armstrong said, has a lot to do with sand being the fish’s preferred place to hide. The fish come up into the water column to feed, but often dive into the sand if they sense danger.
“I mean, it’s amazing to watch,” he said. “They just disappear.”
Not every year yields a bumper crop of these fish. Armstrong described their abundance as cyclical. “There’s a little bit of evidence that when sea herring or mackerel are down, which they are right now, that sand lance come up,” he said. “Because they feed on each other’s larvae and stuff like that.” This year, he said, sand lance are “just everywhere.”
Armstrong said the number of sand lance could “potentially” result in more stripers. “The number of eggs fish produce is related to their nutritional status,” he said. “Because eggs, they’re full of fat, so they take lots of energy to make. So if you’re in good shape, you put out a lot of eggs. If you’re not, you put less, so if you get a bunch of really healthy fish feeding on them, then you may have better reproduction. “
The fish “make good bait, for sure. They’re just hard to get,” Armstrong said.
They’re not a big part of the bait market, he added. “There’s a very, very, small fishery, just a handful of guys who go out with beach seines and try to get them on the sand flats in the estuaries. And they land some, but not very much. We regard them as so important that a couple of years ago we banned the harvest at large scale. Not that it was going on, but we wanted to prevent it. There are big-scale fisheries in Europe where they land tens of thousands of metric tons, and we don’t want to go there. We think they’re too important as the base of the food chain.”
In Europe, sand lance are processed into fish meal, he said. “We actually rarely see them on our trawl survey that we do twice a year,” he said. “You know, we do hundreds of fish. But when they hear that trawl coming, they dive into the sand, and the trawl just rides right over them. So we rarely see them in the net.”
All in all, Armstrong said sand lance are a vital part of the marine ecosystem. “They’re a really, really important species,” he said.