* Tourism sector struggles to calculate effect of Paris bloodshed
* Share prices in travel companies fall sharply
* Workers in tourism concerned Paris Christmas season may be hit
By Dominique Vidalon and Ingrid Melander
PARIS, Nov 16 (Reuters) - The carnage in Paris has sent shudders through the tourism sector in one of the world's most visited cities with hotel owners, tour operators and others in the industry hoping the expected drop-off in visitors will not last long.
Shares in tourism companies fell sharply across Europe on Monday on expectations that people will cut back travel plans after Islamist militants launched coordinated attacks across Paris killing at least 129 people in locations of the type that might be visited by tourists.
The Louvre and other attractions such as the Paris Opera reopened on Monday after shutting due to the killings, but Disneyland Paris remained closed through Tuesday and the Eiffel Tower will stay closed until further notice.
"It is going to be very difficult in the coming days. The sector is going to hurt," said Georges Panayotis, president and chief executive of hospitality research group MKG.
The damage to tourism would be greater than after the January attack on the Charlie Hebdo magazine and a kosher supermarket, since it was bigger and broader, Panayotis said. "The entire world is looking at France," he said.
France has been on high alert since the January attack by Islamist gunmen who killed 17 people.
Islamic State claimed responsibility for the latest killings in retaliation for French air strikes in Iraq and Syria. Gunmen systematically killed at least 89 people at a rock concert by an American band before blowing themselves up. In another attack gunmen fired randomly into a bar.
Between people who cancelled trips and those who shortened their stays, the industry is sure to see an impact, but Francois Navarro, managing director of the Comite Regional du Tourisme Ile de France, told Reuters it was too early to give figures.
"The feedback I am getting from visitors and tour operators is that there is no panic," he said. "There will be an impact. The question is: will it last until the Christmas holidays or will business pick up in the next 15 days?"
Hotel group Marriott is waiving cancellation fees for bookings at its 15 properties in Paris through Nov. 28 and has increased security at a number of those properties.
Along the banks of the river Seine that runs through Paris vendors were nervous at the traditional stalls that sell postcards and souvenirs from the "City of Light".
"I fear for the season to come, from now on it will go downhill," said Florence Muller, who works at a stall near Notre Dame cathedral. "Contacts at travel agencies tell us U.S. tourists are cancelling their trips."
On Monday morning, the line of people outside the cathedral was much shorter than usual, according to Christophe, who makes a living driving tourists around in his bicycle rickshaw.
"There's just no one, there's a huge difference," he said. "We can see that people are afraid, just by the way they behave. The Christmas season is coming soon and it's usually great business for us between mid-December and the first week of January. It won't be the same this time."
On the Paris bourse, Air France, Aeroports de Paris, Eurotunnel and hotel group Accor were all down about 5 percent or more over concern that tourism will see a downturn.
Air France, however, said it had seen no immediate impact on plane occupancy over the weekend and that it is maintaining its flight schedules for the coming days.
"There have been no massive cancellations of trips or people deciding to leave the country," a spokeswoman said. "It has been a normal weekend for operations."
Travel company Thomas Cook of Britain, which has the greatest number of foreign visitors to France across the Channel, said it has already assisted two bookings where couples had chosen to leave France early.
Effective immediately, its policy allows for free amendments or cancellations for customers with future bookings to Paris and Disneyland Paris, up to and including November 20.
Disneyland Paris will be closed through Tuesday as part of France's three-day national mourning period. The theme park, which receives 14.8 million visits per year, said it was too early to discuss the financial impact.
At the Eiffel Tower, the tallest structure in Paris which has become a symbol of France, there was no reopening date set. With more than 7 million visitors a year, the Eiffel Tower is the world's most-visited monument you have to pay to visit.
Following the Charlie Hebdo attack, Paris hotels saw their occupancy rates drop 3 to 5 percent between January 8 and 12, with the drop accelerating to 10 percent between Jan 15 and Jan 18, MKG research group figures showed.
France, which has been struggling to revive its economy, is normally the most-visited country in the world, with Paris hosting 32.2 million visitors last year.
According to Maisonneuve Global Advisors, France earned $255 billion last year from tourism making it sixth biggest in the world when measured by contribution to GDP.
The bloodshed on the streets of the French capital follow recent attacks claimed by Islamic State on a Russian passenger plane killing 224 people and bombings in Lebanon in which 43 died, all linked to the war in Syria.
It was the worst such attack in Europe since the Madrid train bombings of 2004, in which Islamists killed 191 people.
"There is a point in the public psyche where a succession of isolated events link together to create a pattern," Virginie Maisonneuve said in a report. "This of course could have a negative impact on sentiment and in turn on economic growth at a time when global growth is fragile."
Gill Johnson from Mississippi, who was visiting Paris with her granddaughter, said she did not consider cutting her trip short. "It's been a bit of a bummer that everything is closed but we totally understand," she said.
Liam Smith, who lives in London and works in advertising, said he and his partner were going through with plans to visit Paris this weekend.
"I'd be lying if I said I was completely at ease," Smith said, but added: "Once we start letting attacks like these change how we live our lives, we're giving the attackers what they want: control and power through fear." (Writing by Martinne Geller in London; Additional reporting by Pascale Denis, Cyril Altmeyer and Geert De Clercq in Paris, Victoria Bryan in Berlin and Costas Pitas and Alistair Smout in London, editing by Peter Millership)