NEW YORK » It's not your average library collection: bits of scorpions and snakes. Leeches from a hippopotamus.

And yesterday, officials of the American Museum of Natural History and the U.S. National Park Service signed an agreement for samples from endangered species in America's parks—including Hawaii's nene goose—to be added to the museum's existing DNA collection.

The frozen samples provide researchers with genetic materials to study and help protect hundreds of species. The first new submissions will be blood samples from foxes in California's Channel Islands National Park, followed by specimens from the American crocodile and the nene.

Underground in the laboratories of the museum, which was featured in the 2006 Ben Stiller movie “;Night at the Museum,”; a half-dozen metal vats cooled with liquid nitrogen can store up to 1 million frozen tissue samples. They are stored on racks in bar-coded boxes linked to a computer database so they can be located in seconds.

The park service does not have such a state-of-the-art facility. With this kind of DNA analysis it can better manage existing animal populations, using genetic relationships among the samples to trace animals' movements on land and estimate population sizes.

The lab is part of the Ambrose Monell Collection for Molecular and Microbial Research, which has allowed geneticists to use its samples for free since 2001. Researchers collect tissue samples from animals in the wilderness—an effort essential to Earth's biodiversity at a time of massive species loss.

Julie Feinstein, who heads the museum's sample collection, emphasizes that although DNA is extracted from tissue, cloning “;is not part of our mission.”;

The main goal, museum officials said, is preservation of species.

The National Park Service sites with the most federally listed threatened and endangered species include Hawaii's Volcanoes National Park, Haleakala National Park and Kalaupapa National Historical Park.