If you dive in Massachusetts, itâ€™s only a matter of time before youâ€™ll notice that some folks seem to end their boat dives with a catch bag bursting at the seams with scallops, and if you love seafood as much as I do, youâ€™ll likely start to wonder what you might have to do to come home with a meal like that. The short answer is simply â€œPick some up and take them with youâ€, but thatâ€™s advice you can only take if you can find some scallops to pick up in the first place. As those of you whoâ€™ve read my short guide to hunting lobsters are well aware, I think it's a good idea when hunting to know a thing or two about your quarry. Let's start by learning a few things about scallops, and see if that doesnâ€™t help us understand where to look for them.
There are two types of edible scallops that can be found in Massachusetts waters, but since the bay scallop is both the smaller of the two and easier to harvest from ell-grass beds with rubber boots than with scuba gear, the focus of our discussion will be the larger scallops known to biologists as Placopecten Magellanicus, and to the rest of us as Atlantic sea scallops, smooth scallops, or giant scallops.
Photo courtesy of NOAA archive
Sea scallops are bivalve mollusks, meaning that they have two shell halves and are closely related to the clam family. Their shells have a fan-like shape, radiating threadlike ridges, readily visible concentric growth rings, and they flare out to form small â€œwingsâ€ near the hinge where the two shell halves meet. The shell halves, or valves, are lined with a mantle from which small sensory tentacles and hundreds of blue eyes protrude. The shells are typically five to six inches in diameter, and although scallop shells larger than 7 inches are rare, they can sometimes reach as much as nine inches.
Sea scallops are active swimmers. Their shell halves are connected to one another via a strong muscle known as the adductor, which scallops use to first open their shells and then rapidly snap them shut, thereby propelling themselves backwards through the water. For this reason, the adductor muscle in scallops is more developed than it is in its non-swimming cousins the clams, oysters, and mussels. It is this adductor muscle that we consider the edible meat of the scallop, and the part that therefore motivates the scallop diver. The rest of the scallop is usually either discarded or used as bait for post-dive fishing, although in some parts of the world remote from Boston, the roe is retained and eaten as well. It is well worth noting that it is the discarded portions that can be contaminated by â€œred tideâ€. The retained adductor muscle of scallops is generally considered safe to eat when other shellfish fisheries have been closed due to blooms of red tide algae.
Life Cycle of a Sea Scallop
Every year in the late summer and early fall, scallop spawning begins. Iâ€™ll spare us the details of that process, and suffice it to say that after they are fertilized, the eggs drift with the current until they hatch into plankton-like larvae. These larvae, having only rudimentary swimming ability, continue to drift for about a month or two until they have developed the ability to excrete the sticky byssal threads they will use to anchor themselves to the bottom. This more developed scallop, called a spat, then descends to the bottom, and attaches itself to an available shell, rock, animal, or other surface. Spat are very fragile, and any who are unfortunate enough to descend onto loose sand will find themselves quickly destroyed by the shifting bottom.
Once anchored, the spat will grow until it eventually loses its byssal attachment and becomes a free-swimming juvenile, which will begin to reach sexual maturity at about two years of age. Scallops remain active, swimming to avoid predators, moving with the currents, and through growth and exercise quadrupling the weight of the adductor muscle until they are between four and six years old, when they reach a shell diameter of about four and one half inches. The movements of young scallops are usually localized, and tend to be strongly influenced by currents. As such, beds of young scallops tend to move with the currents while beds of large adults tend to remain relatively fixed. Populations on Georges Bank tend to remain in that area, as the currents circulate and bring the drifting larvae back to the areas where they were spawned, leading to the spat settling out among the adults.
Sea scallops are opportunistic filter feeders, using their gills to move and filter water containing suspended particulate material. Their diet primarily consists of phytoplankton and microzooplankton, and they have the ability to select which of the food particles they filter will be ingested. Unwanted particles are expelled and carried away by the current.
While adult scallops depend on some water movement to bring them food and carry away waste, too much current makes it difficult for scallops to â€œgrabâ€ passing food particles. Likewise, too much inorganic matter suspended in the water column can make feeding difficult, so they tend to feed in areas with relatively little sediment.
Scallops are delicious, but we arenâ€™t the only ones who think so. It seems like a tasty, boneless medallion of meat appeals to just about every carnivorous creature under the sea. Since they are planktonic, scallop larvae are consumed by all manner of filter feeders from mollusks to whales, and the juvenile and adult forms are favorites of cod, wolfish, pout, sculpin, flounder, lobster, crabs, clam worms, and above all sea stars.
Fortunately for scallops (and us), as the shell diameter increases, predation decreases. It becomes much harder to crush, chip, or pry open the shells as they grow larger, so those that survive the first few years of adulthood are likely to live long enough to make it into your bag.
There isnâ€™t really much special gear need for scalloping, as you essentially just want to be able to pick them up, get them back to the boat, clean them, and take the meat home. Hereâ€™s the equipment I use to get the job done easily.
Iâ€™ve been on several dives where I saw scallops and didnâ€™t have a bag with me. Iâ€™m a pretty poor juggler, so my best effort so far in that case was to surface with six of them. Considering that I had to use my dump valve with one hand, Iâ€™d say that was pretty good, but if getting scallops is the purpose for your dive youâ€™re almost certainly going to want to come home with more than that. If so, youâ€™ll want a place to put them, and when you need something to put stuff in, thereâ€™s nothing quite like a bag.
Sure, you could bring an old burlap sack, and it would probably be just fine, but there are plenty of bags available at your local dive shop with features that make them much nicer to use. Which features you select are up to you, but itâ€™s a good idea to get one that can be latched shut, has a wide mouth when open, drains readily, and is both big enough to hold a lot of scallops and small enough to be manageable. I got the biggest bag I could when I went shopping, and while it does hold plenty of â€œcatchâ€, it also billows like a sheet in the wind when itâ€™s nearly empty, and that can be a bit of a hassle underwater. Pick what works for you, and consider securing a metal bolt snap to it so you can clip it off to a D-ring or lift bag.
Lift Bag and Reel
A full bag of scallops can be very heavy, and also very negatively buoyant. In order to swim a full bag to the surface, youâ€™d have to put yourself in a potentially hazardous position by inflating your BC bladder well beyond what would normally be required in order to keep you neutral. Accidentally dropping the bag under those circumstances could cause you to rocket toward the surface uncontrollably, and of course thatâ€™s a scenario any prudent diver will try to avoid.
Taking along a small lift bag with a 50lb capacity and a reel with about 150 feet of line on it can provide a far safer means of getting your scallops to the boat. When your catch bag starts to get heavy, instead of adding air to your BC, secure your catch to the lift bag and put a quick puff of air into it. Add just enough to make the lift bag â€œstand upâ€, but not enough to make the catch bag buoyant. Itâ€™s better to add too little at this point than too much. Continue to add small puffs of air to the lift bag until its buoyancy just begins to offset the weight of the catch bag, which will allow you to move it easily while still maintaining safe neutral buoyancy.
When your catch bag is as full as itâ€™s going to get, attach your reel to the lift bag. Unlock the reel so its spool can spin freely, but keep a thumb on the spool so it stays put and doesnâ€™t tangle. Check to see that you, your buddy, and your gear are clear of the bags, and then check that there are no entanglement hazards like mooring or lobster lines above you. Put a little more air into the lift bag so that it becomes slightly buoyant. Release the bag and let it ascend until it reaches the surface, and then make a slow, controlled ascent beneath it while reeling up the slack in the line. Unless youâ€™ve made â€œdrift diveâ€ pickup arrangements with the boat captain ahead of time, remember to stay close to the mooring line during your ascent!
You probably wonâ€™t find a special 3 Â½ inch scallop measuring gauge, but that really shouldnâ€™t be a problem, as any scallops smaller than four inches are obviously small, and scarcely worth bothering with. Still, if you want to be able to check that your scallops are of legal size, any 3 Â½ inch measuring device will do. A ruler is an obvious choice, but if you plan to buy a knife for scallop cleaning, one with a 3 Â½ inch blade (or a mark at 3 Â½ inches on the handle) would be perfect!
The best knives for scallop cleaning have blades that are thin and short (often less than 3 inches), and they sometimes have a rounded tip. They are available commercially, but many people choose to use a short filet knife or even a shallow sharpened spoon instead. In a pinch, you can use a dive knife, but having the right tool for the job will make it easier and likely give you better results.
After shucking, youâ€™ll want a sealed storage container to hold your meat. Tupperware, takeout soup containers, and the like are all fine, but I prefer Ziplock freezer bags, since Iâ€™m an optimist and I can easily pack several in case I catch my limit. After all, I do have a big catch bag.
Where to find them
Generally speaking, the easiest way to find a bed of scallops is to find someone who already knows where a bed is, and then have them take you there. Local dive clubs, retailers, and charter boats often schedule scallop dives, and by signing up for one of these you can greatly improve your chance of having a successful scallop dive. If, however, you have access to a seaworthy boat and are keen to strike out on your own with dreams of hitting the mother load, it will be helpful to know where scallops like to live, so you can look for places like that.
For starters, the sea scallop population is distributed on the Atlantic continental shelf of North America from Newfoundland to as far south as North Carolina, which of course is a pretty large area to search. Like most creatures though, scallops like to live where they are comfortable and have an ample supply of food. It also stands to reason that they will be most abundant when these criteria are met in a location where they are protected from predators (such as commercial fishermen) to some extent, and where future generations are kept close by circulating currents. What then does an adult sea scallop consider comfortable? There are basically five criteria for scallop comfort that we will look at: depth, temperature, substrate, salinity, and current.
Concentrations of scallops known as beds typically occur at depths ranging from 55-330 feet of seawater, but may also occur in waters as shallow as 6 feet in estuaries and embayments along the Maine coast and in Canada. At the other extreme, offshore beds have been reported in waters as deep as 1150 feet! South of Cape Cod, warm surface currents tend to drive scallops into deeper water, so that despite abundant scallops in sometimes massive beds, divers are unlikely to find them there on any but the deepest recreational dives.
Fortunately, it is often possible to find scallop concentrations at depths as shallow as 60 feet in the waters North of Cape Cod, which makes Cape Ann, Boston, and the South Shore ideal locations for scallop diving. It is worth noting that the minimum depths for successful scallop diving in Massachusetts all but completely preclude shore diving, as there are very few shore sites from which a diver can access these depths without the aid of a boat or other means of transport.
Scallops prefer chilly water, and have been found to grow most rapidly in temperatures between 50 and 60 degrees Fahrenheit. They can survive lower temperatures to some degree, but temperatures any higher than 70 degrees will quickly prove fatal to them. Fortunately, the temperatures scallops prefer are the same temperatures we are likely to encounter when diving in Massachusetts waters, and lethally warm temperatures at depth are not usually something we need to be concerned about encountering here.
Adult sea scallops are generally found on what is sometimes described as â€œbroken bottomâ€, a flat mixed seabed substrate of firm sand, gravel, shells and rock cobble. If the seabed material is too fine, and there is a large quantity of suspended inorganic particles, this can interfere with feeding, so scallops will tend to avoid these areas. If there is too much bottom structure, there will tend to be a greater abundance of predators. However, in the vicinity of wrecks and other obstructions, it is sometimes possible to find beds that take advantage of the refuge that these â€œhangsâ€ offer from the nets of trawlers, whose captains will typically avoid them if possible.
As I said before, scallops require some water movement for feeding, respiration, and removal of waste. Scallops from areas with good water circulation often seem to have firmer flesh and less grit than those found in areas where the current is poor. A mild current of about 10 cm/sec (or .2 Knots) seems to be ideal, while currents above .5 Knots make it difficult for them to feed efficiently. In the simplest terms, scallops like a gentle flow. As an additional note, scallops like the salinity of undiluted sea water, so current resulting from a freshwater source is less than ideal. In fact, if the salinity drops below 16.5%, it can be deadly to sea scallops.
We know now that we are most likely to find scallops in mildly cold waters north of Cape Cod, in depths greater than 60 feet, living on flat broken bottom where there is a mild current of â€œfull strengthâ€ seawater, often (but not necessarily) in the vicinity of wrecks or other â€œgear foulingâ€ obstructions.
How to Catch Them
Once you've found the scallops, youâ€™re on seafood easy street. All you have to do at this point is pick the little suckers up, and drop them in your bag. There is a minimum size to keep in mind, but just try to grab the large ones and you can discard any that are undersized later. At this point, you should concern yourself with filling your bag before your remaining gas or bottom time runs low. At the depths that scallops are likely to be found, no-decompression limits tend to be short, and it can be tempting to stay too long. In a word, donâ€™t. Scallops are delicious, but not worth drowning for, and thereâ€™s always another day to dive.
A big bag of scallops can be quite heavy, and also quite negatively buoyant. If you try to carry them to the surface it will require having plenty of lift in your BC. Ascending this way from depth can be extremely dangerous, as accidentally dropping the bag will make you very buoyant, very suddenly, and can easily cause an uncontrolled ascent. It is a good idea to use a small lift bag and reel instead, so that you can send your bag to the surface under control and then ascend normally to meet it. If you are unfamiliar with the use of a bag and reel, I recommend asking a qualified instructor, or at the very least practicing with a buddy in a controlled environment first. Thereâ€™s a lot that can go wrong, but like everything else there are tricks to it, and it becomes easy with practice.
How to Clean Them
While Sea Scallops can use their adductor muscles to close their shells, they cannot hold them closed for very long. Because of this, once they have been removed from the water they will quickly dry up and die. Therefore, youâ€™ll want to shuck your scallops immediately after catching them, and get them into a refrigerated container as quickly as possible.
First, toss the undersized scallops overboard so theyâ€™ll have the best possible chance of becoming big scallops later on. Then, get your scallop knife out and select a scallop to clean. Youâ€™ll notice that the top shell is more convex than the flatter bottom shell. Slide your knife in next to the hinge, and work it outward along the bottom shell in order to cut the adductor muscle free.
Open the scallop up, and look for the adductor. It should be easy to find, as itâ€™s the firm, light-colored round piece of meat. Remove the adductor muscle, and discard the unwanted portions overboard, where the shells can act as new anchor points for future generations of spat. Put the adductor muscles directly into a sealed container, and get them on ice immediately.
If you are so inclined, scallops are quite good raw (sushi restaurants call them hotategai), and safe to eat, so feel free to sample a few right out of the shell. I often eat my fill of fresh scallops before any of them make it home to cook, and I enjoy the looks of surprise from the uninitiated almost as much as I enjoy the food.
As always, your best source for up-to-date information on the fishing laws is the state government, and there are several online resources you can use to find out what you need to know. The Massachusetts Division of Marine Fisheries website is a good starting point, or you can call them at (617)626-1520 for up to date details.
That said, here are some of the regulations Iâ€™ve found in my searches. I donâ€™t claim theyâ€™re complete, and they may have changed since I wrote this, but to the best of my knowledge, what you find here is accurate for now.
322 CMR 6.05 Atlantic Sea Scallop (Placopecten Magellanicus) Management
- It is unlawful to fish for, catch, take, have on board, or off-load from any fishing vessel, Atlantic Sea Scallops the shells of which are less than 3 1/2 inches in diameter from the hinge to the outer edge.
- Notwithstanding 322 CMR 6.05(1), it is lawful to fish for, catch, take, have on board, or off-load from any fishing vessel Atlantic Sea Scallops with shells less than 3 1/2 inches in the longest diameter provided said Atlantic Sea Scallops comprise no more than 10% of the entire lot of Atlantic Sea Scallops. This 10% tolerance shall be determined by numerical count taken at random of not less than one peck no more than four pecks of the entire lot of Atlantic Sea Scallops.
- In any one day, it is unlawful for a recreational fisherman to harvest or possess more than one bushel of whole scallops or four quarts of shucked scallops for personal use.
- No person shall take or possess scallops in excess of the recreational fishery limits as defined in 322 CMR 6.05(3) unless licensed as a commercial fisherman under the authority of 322 CMR 7.01.
- Commercial fishermen who harvest sea scallops by hand must possess a commercial permit endorsed for sea scallop diving.
- No person shall be issued a commercial permit endorsed for sea scallop diving unless he or she is a bona fide resident of the Commonwealth or is a resident of a state that grants equal access to Massachusetts residents.
- Each individual diver on board a vessel where the scallop quantities exceed the recreational possession limit as noted in 322 CMR 6.05(3) must possess a commercial permit endorsed for sea scallop diving.
- Commercial fishermen who harvest sea scallops by mobile gear from waters under the jurisdiction of the Commonwealth must possess a Coastal Access commercial permit as defined in 322 CMR 7.05.
- No scallops shall be landed or brought ashore in the shell unless the area fished is classified as Approved by the Division in accordance with the National Shellfish Sanitation Program.
Now that youâ€™ve managed to get those scallops you wanted, you might be wondering how best to prepare them. There are many delicious recipes for sea scallops, and they can be baked, broiled, grilled, stir-fried, deep-fried, sautÃ©ed, or even microwaved. There are a couple of rules that hold true for almost all recipes though. First, be careful not to overcook them. Theyâ€™re tender and edible before they even touch the pan, and they toughen easily. As soon as they lose their translucent color and turn opaque, theyâ€™re done. Second, if you plan to use them in a sauce, cook the scallops separately and combine them after they are done. Otherwise, the water that cooks out of the scallops is likely to make your sauce too thin.
That said, Iâ€™ll give you one of my favorite recipes to get you started.
Bacon Wrapped Scallops
Scallops (cut in half if larger than bite-sized)
Brown Sugar (optional)
In a skillet, cook the bacon until it is approximately half done and still flexible. Wrap a piece of the bacon around each scallop and secure it by skewering with a toothpick. Sprinkle with brown sugar if desired, and arrange on a baking sheet. Broil for 3 minutes on each side, and serve hot as an appetizer.
Good luck, and happy hunting,