JERUSALEM — It could take more than a century for part of the coral reef off Eilat to recover from the damage it sustained last week when it was struck by an excursion boat.

The 52 passengers and four crew members were rescued by navy and police vessels before the boat sank, some 200 meters from the Taba border crossing.

"It is a disaster. The damage is huge and it will take possibly more than a century for the coral to reach the state it was before," said Noam Meshi, manager of the Coral Nature Reserve, a protected site belonging to the Nature Reserves and National Parks Authority.

He noted that this is one of the virgin stretches of the reef where the living corals are particularly beautiful. Other experts have defined the damage as "inestimable and irreparable."

Although a full assessment of the damage cannot be made until the boat is raised from the seabed and removed, the size of the area hit and the quantities of coral which floated away after being broken off indicate the collision was a catastrophe.

The authority has begun an inquiry. According to spokesman Ofer Greenstein, the initial impression is that the accident was caused by negligence.

The boat, named Jadran, was apparently swept toward the reef by strong winds. At a distance of about 33 feet from the shore, the boat hit the reef with great force. It sank about an hour later in clear view of people on the beach.

Naval officials said that the moment a distress signal from the ship reached them, two patrol ships and rubber speedboats were dispatched to the site, opposite the Princess Hotel just north of the Egyptian border. Civilian boats also participated in the rescue.

Meshi said the broken corals were gathered up, filling several containers. Nature Reserve and National Park Authority specialists are examining the possibility of trying to graft them back onto the reef.

According to Greenstein, initial reports indicate that the tourist boat had been tied to a buoy, but the captain did not notice in time that the ship had broken away and was being carried by a northerly wind toward the reef. The boat had apparently been moored so that passengers could dive and swim.

Regulations require a full watch while the boat is anchored to prevent it coming unmoored or being dragged away unnoticed.

Meshi said the fact that the reef is a popular tourist site could also affect the length of time the reef takes to recover, although he hopes to find an arrangement to limit the impact.

According to Meshi, Jadran used to be the pleasure boat of the late Yugoslavian leader Marshall Tito. It was brought to Israel 15 years ago to serve as a tour boat.