Handout / REUTERS

A veterinary technician reviews the pictures on the monitor as a member of the animal staff maneuvers the ultrasound wand on a pregnant Sumatran tiger named "Leanne" in this October 4, 2012 handout photo supplied by the San Francisco Zoo and released February 14, 2013.

It's anyone's guess what the sex of the 10-day old Sumatran tiger at the San Francisco zoo is.

That's because no human has been inside the Lion House to see the cub, born Feb. 10 to parents Leanne and Larry. Still photographs

taken from the video camera inside the grotto show the striped cub nuzzled against its resting mother.

Zoo spokeswoman Abbie Tuller said the gender of the cub will be revealed in a couple of weeks when a veterinarian goes in for a routine wellness check.

Tanya Peterson, executive director and president of the San Francisco Zoo, said that Sumatran tigers are a critically endangered species and the population in the wild is estimated at less than 400.

Zoo officials also pointed to the excellent prenatal care the Mama tiger received. Leanne is one of the few tigers in the world trained to receive examinations and prenatal sonograms without general anesthesia.

SF Zoo / NBC Bay Area

Baby tiger cub at SF Zoo born Feb. 10.

Leanne is a 9 1/2-year-old female Sumatran tiger. She came to the SF Zoo from the San Antonio Zoo in 2006. This birth is her second litter; her first was in 2008 when she gave birth to three males, who were transferred to other zoos to participate in the Association of Zoos and Aquariums’ Species Survival Plan. Leanne is named for the late Leanne Bovet Roberts, a former SF Zoo trustee and very generous donor and supporter of animal care organizations.

Larry is a 6-year old male Sumatran tiger that came to the SF Zoo in 2012 on breeding loan from the Audubon Zoo in New Orleans, with a stop at the Jackson [Mississippi] Zoo in between. This is the first litter he has sired. He is named in honor of Lawrence Hauben, the late husband of SF Zoo donor Margaret Hauben, who always signed his correspondence, “Love, Larry the tiger."

This birth represents the first tiger born at the SF Zoo since 2008. Prior to that, the last litter of tigers born at the SF Zoo was in 1976.

Arguably the best known tiger in the Bay Area was Tatiana, who fatally attacked a young man on Dec. 25, 2007, and was killed by police. But she was a Siberian tiger and has no relation to the new baby cub.

WWF-Indonesia

A Sumatran tiger cub is photographed by a hidden camera. WWF says the cub was walking through a corridor being cleared by Asia Pulp and Paper in Indonesia.

Is your toilet paper wiping out forests used by tigers, elephants, orangutans and other wildlife? In a report Wednesday, the World Wildlife Fund alleged that a major paper supplier from Indonesia is clearcutting habitat there and targeted a major U.S. distributor to stop buying from that source.

"We found that two brands sold in the United States ― Paseo and Livi ― are made with paper from Asia Pulp & Paper (APP), which is responsible for more forest destruction in Sumatra than any other single company," the World Wildlife Fund report stated. "Paseo is a retail brand of toilet paper, paper towels, napkins and facial tissue, and it is now the fastest growing brand of toilet paper in the United States, according to its marketer."

The distributor, Oasis Brands, didn’t responded directly to the accusation, but defended APP while saying it wants to work with grocery chains to set up a system of monitoring the sustainability of its tissue products.

"Everyone wants the reassurance that the products they buy from Indonesia meet internationally recognized certification standards and are not damaging the precious natural resources of that country," Oasis Brands CEO Philip Rundle said in a letter to the industry.

"Continuous, rigorous auditing has proven APP products are made from sustainable sources and meet well-established sustainability standards," he added. "Now we would like the US grocery industry to see the results of such an audit for themselves. We are confident that APP will meet the expectations of US grocers."

WWF questioned Oasis' defense of the pulp and paper producer. "APP’s forest management operations in Indonesia are not certified as sustainable by any credible third party, "WWF forest expert Linda Kramme told msnbc.com. "There are responsible pulp and paper companies in the US, in Indonesia, and the world over, which employ people and make a profit – all without destroying rain forests."

The group also noted that in recent months eight large retailers -- identified as BI-LO, Brookshire Grocery Company, Delhaize Group, Harris Teeter, Kmart, Kroger, SUPERVALU and Weis Markets -- had decided to stop carrying APP tissue products.

Eyes on the Forest

WWF said an APP supplier was draining this peat forest inside a tiger sanctuary in Riau, Indonesia.

"We applaud each of these companies’ decision to remove these products from their stores," Jan Vertefeuille, head of WWF’s tiger campaign, said in a statement.

More from msnbc.com and NBC News:

• Group: Militia 'slaughtered' 3 families in Syria's Homs
• In Greece, the crisis is making people ill, (literally)
• 'Poster couple' for Calif. gay rights is divorcing