The East Bay Regional Park District marks its 80th anniversary this year, and you can help celebrate by joining the 2014 Trails Challenge.

Now in its 21st year, the Trails Challenge is a program encouraging health, fitness and fun in the regional parks. It's sponsored by the park district, Regional Parks Foundation and the Kaiser Permanente health maintenance organization.

Here's how it works. Beginning Wednesday, visit the foundation website, www.regionalparksfoundation.org, click on the Trails Challenge logo, and register online. Once registered, you can download a guidebook listing 20 trails throughout the regional parks. There are also instructions on how to obtain a free Trails Challenge T-shirt while supplies last.

Travel any five of the trails, or complete 26.2 miles, send in the log that comes with the guide, and you'll receive a commemorative pin while supplies last. Regional parks with challenge trails include Sycamore Valley in Danville, Big Break/Marsh Creek in east Contra Costa County, Briones Regional Park in central Contra Costa, Kennedy Grove in El Sobrante and Lake Temescal in Oakland.

You don't have to hike. Any nonmotorized mode of transport is OK, including horse and bicycle. There are trails accessible to wheelchair users, too. The 20 trails are located throughout the district and vary in difficulty so that all levels of fitness can participate. It's a great way to explore new parklands and discover hidden treasures of an agency that has served the public since 1934.

TEEN JOBS: Although it may seem early to think about spring and summer, the park district will soon offer seasonal full and part-time positions for youth ages 16 and older. Jobs include lifeguards, recreation leaders, gate attendants and student laborers.

The district also has two training programs for student aides to work year-round at visitor centers or in the Public Safety Department. For more information, visit the website at www.ebparks.org/jobs, contact the park district human resources staff at 510-544-2154 or email jobs@ebparks.org.

REDWOOD REGIONAL: In a previous column I mentioned that you could see clusters of overwintering ladybugs at Redwood Regional Park in Oakland. Well, there's a good opportunity this Saturday during a naturalist-led walk from 10 a.m. to noon. It's part of the Saturday and Sunday Strolls series.

This one's a moderate 3-mile loop on the East Ridge, Prince and Stream Trails. Meet at the park's Skyline Gate, which is on Skyline Boulevard a bit south of the intersection with Shepherd Canyon and Pinehurst Roads. For information, call 510-544-3187.

Richmond hikes: There are two hikes from which to choose this weekend in Richmond. The first is from 1 to 2:30 p.m. Saturday at Point Pinole Regional Shoreline, led by naturalist "Trail Gail" Broesder. It's an exploration of life beneath the waters of San Pablo Bay, so be prepared for wet hands and feet. Point Pinole Regional Shoreline is on Giant Highway off Richmond Parkway.

The second hike is from 9 a.m. to noon Sunday at Sobrante Ridge Regional Preserve, led by naturalist Anthony Fisher. Sobrante Ridge has beautiful views and is home to the rare and endangered pallid manzanita shrub. This is one of Anthony's "Tracking the Urban Edge" series, looking for signs of wildlife that live close to our homes. Meet at the trailhead near the end of Heavenly Ridge Lane in Richmond. Both programs are free, though Point Pinole has a parking fee of $5 per vehicle. For information on either program, call 510-544-2233.

BIG BREAK: Wetland bugs will be featured in a hands-on program from 2 to 3 p.m. this Sunday at Big Break Regional Shoreline in Oakley. The idea is to see what the little guys can tell us about the Delta ecosystem. It's free of charge. Big Break is on Big Break Road off Main Street. For information, call 888-327-2757, ext. 3050.