Life's been tough for land turtles these last few years. Their breeding places have been destroyed to make room for building sites, and they've been turned into house pets for collectors who deny them their freedom.

But some people have helped the turtles out, including students at the Hashalom School in Mevasseret Zion. On Thursday they released dozens of them into a nature preserve near the suburb just outside Jerusalem.

The two-year-old school project encourages land-turtle owners, including students' families, to return the animals to nature. "It's hard for students to separate from pets they've raised themselves, but we've managed to collect about 70, and some of them have already been released," says Amit Almog, who teaches animal and environmental studies at the school, with the support of the Karev Program for Educational Involvement.

"We've had to overcome various difficulties, including the theft of 20 turtles from the place where we take care of them."

The release last Thursday, carried out with the Nature and Parks Authority, took place in the Nahal Halilim nature reserve. "We picked this area to revive the local turtle population, which has been reduced by fires," Almog says. "We set all the turtles here free."

The turtles released last week were all more than 2 years old, which increases their chances of survival in the wild. "At this age, their shells are hard and they can protect themselves," Almog says. "When they're younger, the survival rate is only a few percent; they're eaten by predators such as cats and crows."

There is a reproductive core of about 10 turtles at the school; as they reproduce more turtles will be released into nature. Their survival in the wild may be measured by unique marks on their underbellies.

"We've photographed each turtle's stomach, so we can identify them in the future as turtles we set free," Almog says.