November 26, 2023. Members of the Sand lance Mafia assembled onboard the F/V Miss Emily in hopes of finding spawning ripe fish for our 2023 experiment. After loading our gear, Captain Kevin navigated us towards the southwest corner of Stellwagen Bank and deployed our beam trawl for our first 10-minute tow.
Boom! From the first tow, fish in spawning condition were brought on board, counted and separated by sex. Now, we just needed to repeat this for 13 more trawls until we had a sufficient amount of fish to start the experiment. After collecting 40+ spawning ripe males and females, we headed back to port wile starting to strip-spawn. This is an all hands on deck process, where we need to work together to evaluate the fish in real time and use the most ripe fish available.
The successful strip-spawn event now marks the start of our most ambitious experiment to date, where DNA and RNA samples will help us further investigate potential mechanisms behind the sand lances high CO2 sensitivity.
Blastula stage sand lance embryos ~ 24h post fertilization
The sandlance 2023 team after the first trip to Stellwagen Bank this year (left to right: Sam, Emma Siegfried, Chris Murray, Lucas Jones, Zosia Baumann, David Wiley)
On 26 November, Lucas is back at the Rankin Lab with the goods!
A potential ripple effect from carbon in the atmosphere could have severe impacts throughout the ocean ecosystem
This photo shows sand lance embryos that have and have not hatched. Sand lance have trouble hatching at future ocean CO2 levels (photo courtesy of Emma Cross).
When carbon is emitted into the atmosphere, about a quarter of it is absorbed by the earth’s oceans. As the oceans serve as a massive ‘sink’ for carbon, there are changes to the water’s pH – a measure of how acidic or basic water is. As oceans absorb carbon, their water becomes more acidic, a process called ocean acidification (OA). For years, researchers have worked to understand what effect this could have on marine life.
While most research so far shows that fish are fairly resilient to OA, new research from UConn, the University of Washington, the National Oceanic and Atmospheric Administration (NOAA), and Southern Connecticut State University, shows that an important forage fish for the Northwest Atlantic called sand lance is very sensitive to OA, and that this could have considerable ecosystem impacts by 2100. The team’s findings have just been published in Marine Ecology Progress Series 687.
Sand lance spawn in the winter months in offshore environments that tend to have stable, low levels of CO2, explains UConn Department of Marine Sciences researcher and lead author Hannes Baumann.
“Marine organisms are not living in a uniform ocean,” Baumann says. “In near shore environments, large CO2 fluctuations between day and night and between seasons are the norm, and the fish and other organisms are adapted to this variability. When we stumbled upon sand lances we suspected they are different. We thought that a fish that lives in a more open-ocean offshore environment might be more sensitive than the near-shore fish because there’s just much less variability.”
The project was a collaboration with physical oceanographers, including Assistant Professor of Marine Sciences Samantha Siedlecki and Michael Alexander from NOAA’s Physical Sciences Laboratory in Boulder, Colorado, who modeled CO2 levels in 2050 and 2100 for a specific part of the Gulf of Maine where sand lance spawn. Then Baumann and his team reared sand lance embryos in the lab under experimentally higher CO2 levels matching the projected levels.
There are instances of direct fish mortality as result of elevated CO2, but they are rare, says Baumann. However, sand lance embryos proved to be exceptionally sensitive, and fewer embryos hatched under future oceanic CO2 conditions. The researchers repeated the experiments three more times to avoid jumping to conclusions but each time they observed the same result.
“We found that embryo survival-to-hatch decreased sharply with increasing CO2 levels in the water, concluding that this is one of the most CO2-sensitive fish species studied thus far,” Baumann says.
Sand lances are surely one of the most important forage fish here on the Northwest Atlantic shelf… The humpback whales, sharks, tuna, cod, shearwaters, terns — you name it — they are all relying on sand lance.
With this interdisciplinary approach combining model forecasts and serial experimentation the researchers arrived at a picture that is much more specific.
“We consequently applied principles of serial experimentation, which is a most timely and important topic in ocean acidification research right now,” Baumann says. “Because our findings are backed up by repeated independent evidence, they are more robust than many published ocean acidification studies to date.”
In addition to preventing many sand lance embryos from developing normally, the researchers document a second negative, and novel, response to elevated CO2. Higher CO2 levels appear to make it harder for embryos to hatch.
Baumann explains the lowered pH likely renders enzymes needed for successful hatching less effective, leaving the embryos unable to break through their eggshell (chorion) to hatch.
The results show that by 2100, due to acidification, sand lance hatching success could be reduced to 71% of today’s levels. Since sand lance are such a critical component of the food web of the Northwest Atlantic, this marked decrease in sand lance would have profound impacts throughout the ecosystem.
“Sand lances are surely one of the most important forage fish here on the Northwest Atlantic shelf,” Baumann says. “Their range spans from the Mid Atlantic Bight all the way to Greenland. Where we studied them, on Stellwagen Bank, they are called the backbone of the ecosystem. The humpback whales, sharks, tuna, cod, shearwaters, terns — you name it — they are all relying on sand lance, and if sand lance productivity goes down, we will see ripple effects to all these higher trophic animals. Even though we humans don’t fish for sand lance, we need to take care of the species because it has such a huge effect on everything else.”
Baumann says this study supports the hypothesis that offshore, high latitude marine organisms like the sand lance may be among the most vulnerable to OA. As a result, these organisms and food webs will likely be impacted first and soon, and we must act now.
Previous research has focused on opportunistically chosen species when testing their sensitivity for ocean acidification, says Baumann, but this should change.
“We need strategic thinking about what species we are testing next, because we cannot test every marine fish species, that’s an impossible task. We should concentrate on fish species that are likely the most vulnerable, and therefore the ones that are probably being affected first and this research makes a compelling argument that those are the fish species at higher latitudes and in more offshore than nearshore environments.”
Bluefin tuna and striped bass crash through the waves. Seabirds wheel overhead and plunge into the water. Gape-mouthed whales rise from below. Schools of cod and dogfish hide below the surface.
While the convergence of such diverse sea life might seem accidental, those in the know thank a small, slender fish called a sand eel for the bonanza.
Also known as sand lance, these three-to-six inch forage fish are a main food source for many of the top predators in the Gulf of Maine and on Georges Bank, including some of the most commercially important species.
As their name implies, sand lance are tied to sand habitat, but not just any sand will do. To avoid predators, sand lance spend most of the night and parts of the day buried. When disturbed, they rocket out of the bottom, then dive head first and at full speed back into the sand.
As a result, their sand of choice has to be coarse enough to hold oxygen for the fish to “breathe” while buried, but soft enough to allow high-speed body penetration. One of the reasons Cape Cod is their Mecca is a band of perfect sand stretching from Stellwagen Bank along the backside of Cape Cod, past Chatham and up through Georges Bank. Whether you are a fisherman, whale watcher or seabird enthusiast, it’s this band of sand, and the sand lance that inhabit it, that makes the Cape special.
Sand and sand lance are the backbone of Stellwagen Bank National Marine Sanctuary, responsible for it being one of the top places in the United States for viewing marine life, and a centuries old, highly productive fishing ground. Yet while fishermen appreciate the importance of sand lance, little is known about their biology and most of the world does not know they exist.
To remedy the situation, a team of researchers led by scientists from Stellwagen Bank National Marine Sanctuary with partners from Boston University, Center for Coastal Studies, University of Connecticut, U.S. Geological Survey and Woods Hole Oceanographic Institution have been studying the forage fish to determine its importance and unlock some of its secrets.
One of the project’s first goals was to identify the sand lance spawning season. Using a specially designed and permitted small-mesh trawl, fished from Steve Welch’s F/V Mystic or NOAA’s R/V Auk, the team captured and examined sand lance. Thought to spawn from late fall through winter, several years of work demonstrated that sand lance on Stellwagen Bank spawn in a very narrow window at the end of November. Eggs are deposited on the seafloor and hatch after approximately six weeks.
Then things get interesting. Once hatched, sand lance are tiny, free-floating larvae for two to three months. Given this long free-floating period and the currents flowing over Stellwagen Bank, many sand lance born on the bank cannot stay there. So where do they come from and where do their offspring go?
To answer this question, the team used hydrographic modeling to backtrack to where free floating particles (like larval sand lance) would have originated prior to their sand settlement in March or April, and where drifting particles would end up two or three months after hatching.
It appears that larval sand lance settling on Stellwagen originate off the coast of Maine; years of highest sand lance abundance correspond to conditions that would have transported additional larval sand lance from as far north as Nova Scotia. The same modeling indicated that larval sand lance originating on Stellwagen Bank transport south to the Great South Channel and Nantucket Shoals (but not Georges Bank). In some years, currents moved them as far as New Jersey.
This is just another example of the interconnected world that creates a productive marine environment. Since few sand lance in the study lived past three years, the dependence on shifting currents to populate the bank could be one thing responsible for boom and bust years typical of sand lance abundance. The team is currently examining genetics of sand lance taken from throughout the Gulf of Maine, the mid-Atlantic, and eastern Canada, to gain additional insight into population structure.
Do boom-bust years influence the distribution and abundance of predators? The team investigated the association of sand lance with humpback whales and great shearwater seabirds by placing satellite tags on both species to track their movements.
Throughout the Gulf of Maine, tracking revealed that both species spend the vast majority of their time over sand lance habitat, and DNA from fecal shearwater samples showed sand lance to be the bird’s main prey. Surveys in Stellwagen also demonstrated a high co-occurrence of sand lance, humpback whales and great shearwaters.
Sand lance feed primarily from February to July, mostly on Calanus finmarchicus copepods. They stop feeding from August through October, with low levels of feeding from the end of November to January. Body growth and fat content show similar trends, with length and fat stores increasing from February to July. After July, the fish retreat to bury in the sandy bottom, conserving energy for spawning.
The team then turned its attention to the future of the valuable fish, something of extreme importance to fishermen. Ripe fish captured in November were strip-spawned on board the boats and transported to Connecticut, where eggs and larvae were raised in special tanks that allowed temperature and acidity to be manipulated to mimic future ocean conditions under climate change. Increased temperature and acidity had a dramatic negative impact on larval survival. According to Dr. Hannes Baumann, whose lab led the work, sand lance may be unusually sensitive to ocean acidification.
The future of sand lance was also a focus of team members Joel Llopiz and Justin Suca from Woods Hole Oceanographic Institution. They came to some worrisome conclusions.
The abundance of tiny C. finmarchicus copepods directly influences sand lance health: Abundant C. finmarchicus led to good parental condition and high reproductive success, while low numbers resulted in poor parental condition and poor reproductive success. Scientists have suggested climate change scenarios in the Gulf of Maine will lead to reduced abundance of this critical copepod resource. Adding to the problem was their finding that warm slope water coming through the Northeast Channel north of Georges Bank led to the death of overwintering reproductive adults.
With the Gulf of Maine warming faster than 99 percent of the world’s oceans, there is concern about the future of sand lance and its potential impact to the productivity of the Gulf of Maine, Georges Bank and other areas. While states with fisheries and other marine resources supported by sand lance cannot solve climate change issues, they can work to make sand lance more resilient to climate change. One way is to eliminate as many non-climate stressors as possible.
For example, in 2020 Massachusetts promulgated a rule limiting daily sand lance landings to 200 pounds. Rhode Island followed suit in 2021. These rules were designed to discourage the development of a commercial fishery for the species, such as the huge industrial fishery in Europe’s North Sea.
Since a commercial sand lance fishery does not currently exist here, adopting this rule by other states would be an easy, proactive way to make our waters, and the people who depend on them, more resistant to climate change disruption.
(Dr. David N. Wiley is the Research Ecologist for Stellwagen Bank National Marine Santuary. Funding for the project was provided by the Bureau of Ocean Energy Management, The Volgenau Foundation, Northeast and Woods Hole Sea Grant, International Fund for Animal Welfare, Stellwagen Bank National Marine Sanctuary and the National Marine Sanctuary Foundation. Dan Blackwood, Dr. Gavin Fay, Peter Hong, Dr. Les Kaufmann, Kevin Powers, Dr. Jooke Robbins, Dr. Tammy Silva, Mike Thompson, and Dr. Page Valentine contributed to the study)
20 March 2020. We are happy to announce that the prestigious journal Fish & Fisheries just published a comprehensive review about the role of sand lance in the Northwest Atlantic Shelf ecosystem. The article, which came out of a workshop on this topic three years ago, reviews the the current state of knowledge about these enigmatic and important forage fish and urges continued efforts to better understand their role in the ecosystem and sensitivity to climate stressors.
This work represents the first comprehensive assessment of this important forage fish in the Northwest Atlantic, though similar efforts have been carried out in the Pacific Northwest and Europe. In the Atlantic, sand lance are observed to be a significant food source for the federally endangered Roseate tern, Atlantic sturgeon and cod, Harbor and Grey seals and Minke and Humpback whales. “This paper is a call to our peers and colleagues that there is a big gap in knowledge, and to bring more attention to these species as unmanaged forage fish,” says Staudinger.
10 September 2019. Hannes started of the new 2019 NECAN Sea Grant Webinar Series with a presentation of our past years of research on the sensitivity of Northern sand lance (Ammodytes dubius) to ocean acidification and warming. The purpose of this webinar series is to highlight four projects funded through NOAA Sea Grant following the release of the NECAN paper published in Oceanography Magazine in 2015, “Ocean and Coastal Acidification off New England and Nova Scotia.”
Thanks to the more than 50 people who attended the webinar. If you have missed it, it’s accessible for free online. See below.
15 November 2018. After a stretch of foul weather kept us from going out to Stellwagen Bank last week, this time all the stars aligned for Emma and Mackenzie. Due to their success in catching spawning ripe Northern sandlance, we are now embarking on our third year of CO2 x temperature experiments on this species!
Here is how Mackenzie Blanusa experienced her first trip to these enigmatic waters:
“This particular sandlance cruise was a day filled with firsts and is definitely a trip to remember. I accompanied Emma, Hannes’ postdoc, up to Scituate the night before the cruise and was given a rundown of what needed to be accomplished. I was a bit overwhelmed at first, because I’ve never dealt with sandlances before and did not know a lot about these fish. Nevertheless, I was eager to learn something new and was ready to help out wherever needed.
The goal of the sandlance cruise was to collect running ripe males and females to do a fertilization via strip spawning. Emma and I were a bit doubtful at first because we got less than 10 sandlance on the first two trolls. However, things got much better by the afternoon, and our most successful trawl caught 147 sand lance. I helped out with the fertilization and deploying the trawl, two things I have never done before. The most exciting part of the day was getting to see humpback whales. Usually they are in the distance but today they were right next to the boat. Everyone on board said that this never happens and it was very unusual so I felt very lucky to have seen whales at such a close proximity.”
Overall, the trip was a huge success and it was very refreshing to see everything go as planned. The only downside to the day was driving back home through a snowstorm. I later found out that there was a 73% fertilization success and we got 27,000 embryos for Emma’s experiment. I am very grateful to have gotten the opportunity to help out on this sampling cruise and am looking forward to doing this again in the future!
Emma on the makeshift spawning station for sand lance on board the RV Auk
Mackenzie strip-spawning sand lance on the ship
Added perks of doing research on Stellwagen Bank …
Exactly 0.5ml of sand lance eggs (~ 600) were distributed into each replicate per treatment
On 19-21 September 2017, Chris Murray and Hannes Baumann traveled to Fort Lauderdale, Florida, to attend the ICES (International Council for the Exploration of the Sea) Annual Science Conference in order to present our ongoing NSF and NOAA funded research on potential ocean acidification effects in Atlantic Silversides and Northern Sand lance. Due to Hurricane Irma, which had impacted all of Florida just a week earlier, it was a great relief that the conference could actually be successfully held.
Chris gave a talk and a poster during this session, which was well received and thus a worthwhile exposure for Chris and our lab’s research.
Murray, C. S. and Baumann H. 2017. Growth costs of high CO2 environments in a marine fish: importance of feeding methodology. Talk.
Murray, C. S., Wiley, D., and Baumann H. 2017. A preliminary study testing the effects of high CO2 on the early life stages of the northern sand lance Ammodytes dubius. Poster.
NOAA sanctuaries just published a little blurb online, introducing sand lance and it’s importance to the Stellwagen Bank National Marine Sanctuary, including a small section on the current research efforts funded by NOAA Regional SeaGrant.
“To that end, the team is collaborating with scientists from the University of Connecticut (UConn). UConn study members transport live-caught sanctuary sand lance to their lab, where further generations of sand lance are raised. The resulting larval sand lance are raised in high-tech rearing facilities that can be adjusted to mimic future ocean conditions.”
Seabirds, sharks, seals, whales and more rely on sand lance as a food source. Here, a laughing gull munches one of these eel-like fish. Photo: Peter Flood
4th time’s the charm: sampling spawning ripe sand lance on Stellwagen Bank
On 2 Dec 2016, the sun rises over Scituate, MA, harbor and the fishing trawler that will take us to Stellwagen Bank this time.
On 2 Dec 2016, Chris waits for the action to start, while the trawler is leaving Scituate Harbor
Sandlance embryos, 24h after fertilization. The embryo stage in this species can be up to two months!
Early morning on 2 December 2016, we left Scituate, MA, for the forth time this year, heading towards Stellwagen Bank in search of spawning ripe Northern sand lance (Ammodytes dubius), a winter spawning forage fish of great importance to the Stellwagen Bank National Marine Sanctuary and the object of latest research efforts. While during the last three cruises in late October and November, we saw a progression of ripening in the specimens, up to now we didn’t actually find spawning ripe individuals. Today, though, things are different, and when the first sand lance appear in our beam trawl, we immediately know that today we’ve been at the right time and at the right place.
It seemed an ambitious dream not too long ago, but now we’re happy report that we’ve started an experiment on sand lance embryos in our lab. Thanks to Chris Murray, David Wiley, Mike Thompson, captain Steve and his deckhand Matt for the successful trip!
Early morning low tide at Scituate Harbor on 2 Dec 2016. The calm is deceiving; outside of the harbor the sea is pretty rough
Check out some footage of the trip and the beam trawl operation on board of captain Steve’s fishing vessel
On 27 October 2016, Hannes, Chris and Julie joined researchers from the Stellwagen Bank National Marine Sanctuary (David Wiley, Anne-Marie Runfola, Brad Cabe, Michael Thompson), the USGS (Page Valentine, Dann Blackwood) and the crew of the R/V Auk (Dave Slocum, James Stasinos) to embark on our first of five total sampling missions in this enigmatic marine habitat. Our goal, catching live Northern sand lance, Ammodytes dubius, the so critical forage fish species that is referred to as the “backbone of the sanctuary”, because all kinds of marine predators from whales to tuna to seabirds gather on the bank to feast on them.
Our renewed efforts are part of our recently funded NOAA Regional SeaGrant Project to investigate the effects of ocean warming, acidification and low oxygen on sand lance early life stages.
As before, we first started by deploying a Seaboss sediment grab, which allows our colleagues from the USGS to characterize sediment types in association with the occurrence of sand lance. In addition, however, we brought a small beam trawl along for the first time to find out, whether we could more effectively catch sand lance and then transport them live to our seawater facility at UConn Avery Point. We are happy report that the efforts by all have paid off and that there are now ~ 180 adult ripening sand lance swimming in our tanks. Thanks all, see you again for the second survey in a few weeks!
Check out the video below, made from clips of no less than five different GoPro’s (if you listen carefully, around 2:40 into the clip you’ll hear the singing of some nearby humpback whales):
Reposted from TheCapeCodFishermen, April 28th 2021
