Every year, from November through January, monarch butterflies congregate at Ardenwood Historic Farm in Fremont, their black and orange wings creating an autumn leaf effect in the eucalyptus trees.

It has been described as an intergenerational relay race, during which the monarchs spend parts of their life cycle in habitats ranging from the western slopes of the Rockies to the Southern California coast.

At Ardenwood, naturalist Chris Garcia will host a free program from 2 to 3 p.m. Sunday to see if there are any early arrivals. Meet Chris at the Ardenwood granary for a short, guided walk to the grove where the monarchs hang out. There will be more monarch programs as the season continues.

Ardenwood is located at 34600 Ardenwood Blvd., just north of Highway 84 in Fremont. Entry fee is $6 for adults 18 and older, $3 for seniors 62 and older, $2 for children ages 4 through 17, and free for ages 3 and under. Parking is free. For information, call 888-327-2757, ext. 2797.

OPEN HOUSE: Coyote Hills Regional Park, which is almost next door to Ardenwood, will hold an open house from 1 to 3 p.m. Saturday and Dec. 21, and from 10 a.m. to noon and 1 to 3:30 p.m. on Saturday, Dec. 14, all at the park visitor center.

The open houses are a chance to meet the visitor center's reptiles in residence, hear some nature stories, and work on nature crafts. All ages are welcome. Coyote Hills is at 8000 Patterson Ranch Road off Paseo Padre Parkway north of Highway 84. For information, call 888-327-2757, ext. 3220.

CRAB COVE: Story Time and Nature Fun are in session from 11 to 11:30 a.m. every Sunday in November and December in the Crab Cove Visitor Center at Alameda's Crown Beach.

Kids can hear stories with characters such as the Lorax, hermit crabs and "Swimmy the Fish." Afterward, they can meet live animals, make nature crafts, go on a scavenger hunt or watch nature videos. And fish feeding time is from 3 to 3:30 p.m. every Saturday and Sunday at the center's aquarium. It's all free of charge. Crab Cove is located at 1252 McKay Ave. off Central Avenue in Alameda. For information, call 888-327-2757, ext. 3187.

Veterans day: As a salute to our service members, active-duty, retired, reserve and veteran military personnel will get free parking and entrance on Veterans Day (Monday) at all East Bay Regional Parks.

Military members and veterans of all service branches -- Army, Navy, Marine Corps, Air Force, Coast Guard and National Guard -- are invited to enjoy all park district facilities in Contra Costa and Alameda counties. This benefit to active, reserve, and retired military personnel is new in 2013, approved by the board of directors as part of the consolidated fee schedule. Benefits apply to the individual military person, but not the entire family, except when parking when there is a military affiliated person aboard. Parking is charged per vehicle.