As summer visitors to the shore make their way home, other visitors from across the Eastern Seaboard are coming to the Delaware Bay for a short visit or long-term stay.

They're coming for the food: not deep-fried Oreos or boardwalk pizza and fries, but the plentiful supply of plankton, crabs, clams and shrimp in the bay.

Sharks, sturgeon and an occasional whale have found their way into the Delaware Bay over the years, making it a prime destination as they move up and down the coast during their annual migrations.

They used to be found in much greater numbers, but the bay is home to one of the 10 busiest ports in the nation and the visitors face a number of risks even though policies are in place to ensure their protection.

Several species of sharks, including dogfish sharks and brown sharks, also known as sand and sandbar sharks, take up annual residence in the bay. Other species of sharks visit as well.

"It would not be unusual to find a hammerhead in there," said Jack Carr, science education manager of the New Jersey Academy for Aquatic Sciences in Camden.

Sharks feed on a diet of crabs, clams and herring, all of which are found in decent supplies in the Delaware Bay.

However, the Delaware Bay's most important resource for sharks isn't the food.

Carr said sharks also have made the bay a premiere pupping ground.

When female sharks give birth, male sharks tend to be miles away because they would most likely eat their own young shortly after they're born.

The females do not experience the same temptation because they fast during pregnancy. They have a very low metabolism, so even if the mothers do not eat for weeks, they do not get hungry again until they head out to sea, Carr said.

Carr said sharks tend to get a bad reputation, but these female sharks are nothing like Jaws. In more than 300 years of records, New Jersey has only had 17 shark attacks, according to the International Shark Attack File.

"I wish people wouldn't focus on the attacks," Carr said. "They're just part of a much bigger landscape."

While whales do not frequent the Delaware Bay nearly as often as sharks, they make an impression if they show up.

If a humpback whale is seen, it would be during the late summer and early fall. These creatures measure 55 feet long and often engage in acrobatlike behavior.

Fin whales, which grow to 80 feet and 150,000 pounds, also sometimes wander around the bay looking for food.

But the appearance of a whale can be cause for concern.

A North Atlantic right whale ventured into the bay in 1994. There are only 350 left in the world, so when the young right whale was spotted, many people feared he was lost or tangled up in fishing equipment. But it did not take too long for the whale to find his way out and up the coast toward the Bay of Fundy in Canada.

"I think he was just exploring," said Bob Schoelkopf, director of the Marine Mammal Stranding Center in Brigantine. "The animal was not entangled at all."

The whale, which people took to calling Shackleton, is one of nine that wandered their way into the Delaware Bay since 1980, according to Schoelkopf.

Because of their size, whales get stranded from time to time. One whale had to be euthanized when it got stuck under a house in Reeds Beach, a section of Middle Township in Cape May County, according to Schoelkopf.

"We got this call saying, 'This whale is destroying our house,'" Schoelkopf said. "It was a house right along the shore, and (the whale) was whaling against the wooden supports underneath."

The Atlantic sturgeon also finds its way into the Delaware Bay during its spawning season, which occurs in late spring and early summer.

No one knows how many Atlantic sturgeon call the Delaware Bay home because the species is difficult to track, but the fish has a long history in the Delaware.

The sturgeon has been around for more than 100 million years, but in the late 1800s, sturgeon in the area were caught in vast numbers, as many as 6 million each year. The sturgeon were so plentiful that the town of Bayside in Greenwich Township, Cumberland County, was once known as Caviar.

"Most people aren't aware that caviar was produced right here in New Jersey," said Lisa Calvo, executive director of the Seaboard Fisheries Institute in Penns Grove.

The sturgeon takes about 10 to 12 years to mature and lay eggs, so the species was not able to reproduce enough to offset the number being killed. The population has not been able to successfully rebound since, even with a moratorium on sturgeon fishing, Calvo said.

Pollution from human activity has affected the area. Sturgeon spend most of their adult life in saltwater but need freshwater to spawn. They also need sturdy sediment to lay their eggs, and with constant human activity, the sturgeon's nurseries are not getting any opportunities to expand.

The good news is that all of these sea creatures continue to reproduce. The bad news is they still face all kinds of risks to their survival across the globe and close to home.

Sharks, sturgeon and whales all face similar risks once they venture out of American waters where they are hunted for food. Carr said the shark population has declined significantly worldwide because they are caught for their fins to make shark fin soup, a delicacy in parts of Asia.

Moratoriums on fishing for these species are in place locally, but sturgeon and sharks are sometimes caught in nets designed for other species. They also get struck by the many boats going in and out of the Delaware Bay.

People who study the sturgeon are also concerned about a U.S. Army Corps of Engineers project that would deepen a channel by 5 feet to 45 feet between Cape May and Philadelphia.

Naturalists have raised concerns that the machinery used for digging up sediment could harm these creatures, but the corps said that should not be the case.

Scientists hope that practices such as electronic tagging and constant monitoring, as well as networking with the fishermen who know the area, will help them understand the creatures.

"If we see a recovery of sturgeon, that's an indication that we have a really healthy bay," Calvo said.

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