This holiday season, the Oregon Zoo has many things to be thankful for. Asian elephant Rose-Tu is expecting a small bundle of joy — if you can call a 175-300 pound baby elephant small. The Humboldt penguins have finally returned to their home in the Penguinarium. And beginning today, the 25th annual ZooLights kicks off in Portland.

Here’s a roundup of the zoo’s happenings:

• The Oregon Zoo is recognized worldwide for its successful breeding program, according to its official website. Starting with Packy, there have been 27 elephant births at the zoo since 1962. The new baby elephant could arrive any time between now and January. This is Rose-Tu’s second calf; her first, Samudra, was born Aug. 23, 2008. The zoo will announce visitation hours as soon as mother and baby have bonded and are ready.

• In 2010, the zoo’s Humboldt penguins were temporarily removed from their habitat in order to upgrade a water-filtration system and repair the heating and air conditioning system. The popular Penguinarium reopened last weekend.

• A perennial favorite, ZooLights began in 1988. Using nearly one million lights, the holiday show features “life-size animal silhouettes, moving sculptures, forests of lighted trees and (a) light-bedecked train,” according to a news release. New elements for 2012 include an illuminated forest with 3-D ladybugs. The lights are on display through Dec. 31.

“For 25 years, ZooLights has been a great way to start the holiday season,” said Kim Smith, the zoo’s director. “We’re looking forward to dazzling newcomers and even surprising our loyal visitors when we flip the switch on Thanksgiving weekend.”

General admission for the Oregon Zoo is $10.50 for adults (ages 12-64), $9 for seniors (65 and older) and $7.50 for children (3-11). ZooLights runs 5 to 8 p.m. Sunday through Thursday and 5 to 8:30 p.m. Friday and Saturday. Package tickets (including train ride and admission) are $12.50 for adults, $11 for seniors and $9.50 for children. To purchase tickets and for more information, visit www.oregonzoo.org or call 503-226-1561.