Beach renourishment projects may be controversial, but they can also have unexpected benefits for some inhabitants of the beach, and they are a boon to beachcombers.

Although keeping Sandy Hook accessible to visitors and their cars was the most obvious justification for the 1984 and 1989 renourishment projects, to everyone's surprise, within weeks after the sand pumping ended, birds that require bare beaches for nesting (least terns, common terns, and piping plovers) set up housekeeping and used the beach as a colony area for several summers.

Hoards of beachcombers also descended on the area during and after the sand pumping. After years of scouring the beach at Sandy Hook, I thought I'd found everything worth mentioning, a greater assortment of shells and driftwood than from any other part of the Jersey Shore as well as antique bottles, fishing lures, and welcome and unwelcome flotsam and jetsam from ships and cities. The renourishment of Sandy Hook added a whole new class of materials to my collections - deepwater treasures that are normally beyond the reach of the waves.

Many of the new finds have interesting tales to tell us about the offshore environment where they were dredged up. The source of others is puzzling, but adds to the excitement of beachcombing. Some of my most notable prizes so far include deepwater shells like sea scallops (Placopecten) and mahogany clams (Arctica). These two commercially valuable species are found on New England beaches, but not here because the local water is too warm for them to survive in the summertime. Dredging of the offshore ship channels leading to New York City brought them onto our shore. Remarkably, whole scallop shells, large, thin and fragile as they are, managed to survive a rough trip through dredge pipes to land unbroken on the beach.

A third bivalve, the northern cardita, much smaller than the preceding two species and almost unknown on the beach before, is also fairly common now. All the specimens I've seen are worn down and appear to be relicts from a colder period of our coast's history.

Two warm-water shells that also occasionally appear on the beach are the southern quahog (Mercenaria campechiensis) and the heavy ark (Noetia ponderosa). The southern quahog is larger, much thicker, and less colorful than our northern variety. It is a very common shell on Florida's beaches and in its fossil deposits. Most arks are found in warm seas. The heavy ark is the largest of the three found along our northern coast.

Both of these warm water relicts are reported as live shells only south of the Chesapeake, so their presence in our sediments is proof that the waters off New Jersey must have been at least as warm as Virginia's waters during the interglacial periods.

I've collected two other bivalves fused together in partially fossilized clumps. Interestingly they are not normally found living alongside each other. They are young surf clams (Spisula) and the look- alike false surf clams (Mulinia). Since the former is primarily an ocean clam and the latter a bay inhabitant, they most likely were piled together in some ancient inlet that the dredge passed over in its offshore work, giving us circumstantial evidence of rising sea levels and a migrating shoreline that must have existed east of its present location. Other evidence of shoreline retreat includes relict oyster and bay scallop shells that were darkened by the muddy lagoon sediments that once buried them. These bay dwellers ended up on what became the ocean floor when the barrier beaches that protected their lagoons migrated towards the mainland.

Deepwater snail shells like the waved whelk (Buccinum) and the ridged whelk (Neptunea) are common in New England where the coastal water remains cool year-round. Farther south they rarely end up on the beach, apparently brought within reach of the waves by hermit crabs that borrowed the shells and moved into shallow water. Dredging of offshore sand has added them to the growing list of shells found at Sandy Hook along with what used to be the most elusive find - sand dollars.

Delicate sand castle worm tubes (Sabelleria) can also be found up on the beach now. These fragile aggregations of glued quartz grains disintegrate quickly when they dry out and are handled. They hold together long enough to get to shore because they are supported by the envelope of water surrounding them when they are in the turbulent water of the dredge and the surf.

Just as common and much sturdier than sand dollars or sand castle worm tubes are the number of fossils that can be picked up on the beach. A few sharks' teeth and brachiopods and mollusks have always been present. They were washed from Cretaceous and Tertiary deposits that form the neighboring bluffs of Long Branch and Highlands, the original sources of Sandy Hook's sand. Today they are more common and are joined by both older and younger fossils. I've found, such things as branching bryozoans, perhaps as old as the Paleozoic and a beaked whale (Mesoplodon) skull which is recent enough to be untarnished by the iron or manganese mineralization that usually occurs as fossilization proceeds. Mesoplodon means "armed with a tooth in the middle of the jaw" and the dolphin- shaped beaked whales all have an elongated jaw with few teeth. They probably feed on squid. The skull is a particularly interesting find because this obscure group of open ocean cetaceans is rarely seen along the coast - usually washing ashore as badly decomposed corpses - and may be a branch of marine mammals heading towards natural extinction.

Other mammalian bones turn up regularly, but they are usually old soup bones that only look ancient and mysterious because they have been buried in anaerobic mud and taken on its dark color. Like the numerous pieces of china to be found, they were likely discharged at sea with the kitchen trash from ships.

I have found a number of natural objects on the beach that are definitely not native to this area and also were probably brought here by ship traffic. Sizable pieces of tropical coral, coral rock and coquina stone were probably ballast jettisoned from old sailing ships. Beautifully polished river stones may have been cast from the same ships traveling south, or perhaps are till from the glaciers that barely reached this area. Pumice is also found washed up, but probably floated here on its own long ago since it is too light to function well as ballast.

Artifacts attributable to human activities include a surprising assortment of military ordnance, slag, jewelry, and coins.

The ordnance, artillery rounds and grenades, is a bit of a mystery. Most of it apparently was fired out to sea prior to 1918, during gun testing at Sandy Hook. The rest may have come from accidents aboard military ships. Some of this material is potentially dangerous and should never be picked up by beachcombers. Fortunately there have never been any accidents associated with it. My most interesting find was a small Derringer-type pistol. Like most ferrous metals recovered here, it was blackened and heavily encrusted with iron sulfide from its lengthy stay in the water. It disintegrated rapidly upon exposure to the air. (Note: because of both the military ordnance and Park ordinances, metal detectors are prohibited on Sandy Hook.)

Furnace slag is a common find, attesting to the large number of coal-burning ships and ferries that used to pass here. Its intricate shapes and metallic sheen make this peculiar "rock" a fairly attractive addition to a collection of seashells and other treasures from the shore.

Jewelry and coins are perhaps the most exciting artifacts found on the beach. There are certainly more stories of treasure in this area than recovered loot. Vague legends of Captain Kidd and other corsairs notwithstanding, coins, including gold ones, have been found in this area after dredging operations. The best-documented incident occurred in Highlands in April, 1948, when William Cottrell, a local lobsterman whose family still sails out of here, found 28 one-ounce gold "Johannas" on the town beach. According to local legend this is the very site of James Fenimore Cooper's story "The Water Witch," a fictional account of a pirate captain who smuggled Old World riches ashore here long ago. The rare and valuable "Johannas," dating from the mid 1700's, commemorate Portugal's King John and are said to be worth thousands of dollars each today.

Although I've never been as lucky as some other beachcombers I've met or heard about (one of whom really did find a piece of a gold coin here on Sandy Hook) I have come across some worthwhile discoveries. Copper and other nonferrous metals are more durable than iron and survive exposure to the saltwater for lengthy periods. Occasionally I've found weathered old rings and other heirlooms that must have fallen overboard long ago, perhaps during one of the many shipwrecks here. I've also seen Indian Head pennies and even English coins from the early 1800's that were still quite recognizable, although hardly collectors' items after being in the ocean. A number of people have also brought me mysterious coins about the size of quarters that were probably tokens for the one-dollar ferry that ran from New York City to the Jersey Shore at the turn of the century.

I used to rush to the beach after a storm, worrying that all the good treasures would be found by others. I realize now that the ocean will always be washing up more than I can carry away, regardless of how many beachcombers get there before me. Of course it always helps to be in the right place at the right time, so keeping abreast of dredging operations is important.

As erosion problems increase and more beaches are renourished, tax dollars will be spent trying to do the work of the waves. However such projects also seed the beaches with plenty of treasure for beachcombers.

Something to think about:

• What evidence do we have of climate change?
• Describe evidence that we know supports a rise in sea level.
• Identify two ways that shells, etc. get onto the beach.

Dave Grant was the Monmouth County Coordinator for the New Jersey Shoreline Master Plan.