September 2018

Special Issue on Mathematical Aspects of Physical Oceanography

Oceanography | Vol.31, No.3

SIDEBAR | Sand Lance: Newcomers to Fishery Management Plans

To explore the role of a tiny fish in the North Atlantic Ocean ecosystem, 55 sci-

entists, natural resource managers, and conservationists attended a sand lance

workshop in May 2017 at the Parker River National Wildlife Refuge in Newburyport,

Massachusetts.

The participants concluded that research is needed into how climate change

may influence the fish, and what effect possible offshore energy development or

sand and gravel mining may have on sand lance.

“We have an opportunity to proactively manage a fish that’s not currently tar-

geted for commercial harvest in the US,” says biologist Lynda Welch of the Maine

Coastal Islands National Wildlife Refuge. She, Wiley, and Michelle Staudinger, sci-

ence coordinator of the Northeast Climate Science Center at the University of

Massachusetts Amherst, were co-organizers of the workshop.

“There’s no active talk—yet—of a sand lance fishery,” says Wiley, “but there’s also

no protection for sand lance or the ‘ecosystem services’ they provide.”

For insights into what a fishery management plan for sand lance might look

like, the scientists are reviewing harvest levels for species with similar ecosystem

roles, such as herring and menhaden in the Northeast and Mid-Atlantic regions.

“Management plans for these ‘forage fish’ must balance the needs of the fish with

those of commercial endeavors,” says Staudinger. “We’d like to see the same

approach for sand lance.”

The researchers say that US fisheries managers can learn from overharvesting

of sand lance in the UK. Uncontrolled fishing for sand lance there led to crashes

of seabirds such as black-legged kittiwakes, which depend on sand lance. To

avoid a repeat, the UK sand lance fishery is now managed as several smaller sub-

populations rather than one overall population. That allows biologists to change

harvest levels based on the presence of seabirds, whales, and other sand lance-

eating species.

The future for North Atlantic humpback whales, says Wiley, depends on a fish so

small it’s a mere glint in the sunlight.

are near the seafloor. One humpback the

researchers studied side-rolled every 6 m.

The maneuver netted 10 to 17 scoops of

fish per dive.

Where sand lance are found in the Gulf

of Maine, so, too, humpbacks. Although

last summer’s research cruise was sched-

uled to depart from Provincetown, the sand

lance—and the whales—took up residence

off a different Cape Cod port, Chatham. To

keep up with the shifting scene, the sci-

entists moved R/V Auk from its berth in

Provincetown to a dock in Chatham. “We

may be all about whales,” says Wiley, “but

they’re all about sand lance. So we look at

where sand lance are concentrated.”

Adds Mike Thompson, a spatial ecol-

ogist at the Stellwagen Bank National

Marine Sanctuary, “Whales, seabirds like

shearwaters, and pretty much anything

looking for a meal here is feeding on

these fish. We’re starting to understand

that on Stellwagen Bank, it all depends on

sand lance.”

To track the fish, Wiley, Thompson, and

crew use the SEABed Observation and

Sampling System, or SEABOSS. This boxy

eye-in-the-sea allows researchers to col-

lect sediment samples and obtain videos

of sand lance seafloor hangouts. Sand

lance surveys are conducted at 44 sta-

tions on or near Stellwagen Bank at vari-

ous times of year, including about a month

before the whale cruise in June.

TO TAG A WHALE

R/V Auk serves as the mother ship of two

smaller boats, the rigid-hulled inflatable

boats (RHIBs) Balena and Luna. Balena

ferries biologists to the center of a whale

pod. There, in an attempt to place a track-

ing tag on a humpback, the researchers

nose up to a whale whose flank, where

the tag will be placed, is exposed.

The digital tag, or DTAG, is attached with

a suction cup. This acoustic recording

tag provides data on the whale’s orienta-

tion (pitch, roll, and heading) and depth—

50 times per second. The DTAG also

records all sounds made and heard by the

tagged whale, says Wiley. Visualization

software

called

TrackPlot

provides

(right) A Cory’s shearwater with a

sand lance in its bill. The slender body

shape of sand lance makes the fish an

ideal prey item for seabirds. Image:

NOAA/SBNMS

(below) Feeding humpback whales

concentrate sand lance at the surface,

where the fish are also eaten by sea-

birds. Image: NOAA/SBNMS; NMFS

permit #782-1719

Oceanography | Vol.31, No.3

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