For many of us, diving is as much about buddy time as bottom time. And from coast to coast, there’s always a reason for the lot of you to don your gear for a good-conscience cause, from rallying against lionfish to scooping up trash during a favorite local shore dive. In the name of paying it forward, venture forth.

LIONFISH DERBIES

Scientists and divers team up in areas affected by invasive lionfish — Florida is ground zero in the U.S. — to target this invasive species that has a turbo-charged reproduction rate. (A single female lionfish can lay 30,000 eggs per month, and the voracious creatures are responsible for decimating reef-fish populations.) Get a team together for a derby to help control the population while striving for prizes during these fun competitions.

“Derby weekends are intense,” says Keri Kenning, communications manager at Reef Environmental Education Foundation, an organizer of lionfish derbies. “We measure every single fish that comes in down to the millimeter.” Teams are scored on the number of fish caught; points are given for the largest and smallest specimens too. REEF’s events are usually a two-day affair, with captains meetings held the night before the big hunt.

“It’s usually a collegial, jolly atmosphere, where the collective group is fired up and energized about going out to remove lionfish the following day,” Kenning says. Afterward, there’s lots to eat — lionfish ceviche, anyone? — and crowds gather to celebrate the cause.

When to Go REEF sponsors several lionfish derbies throughout the year in the Florida Keys, South Florida and the Bahamas. Summer 2013 events include derbies on July 27 in Fort Lauderdale, Aug. 17 in Palm Beach and Sept. 14 in Key Largo (reef.org/ lionfish/derbies).

Next Page: Beach Cleanups

CLEANUPS

Nothing puts a pit in a diver’s stomach like seeing the seabed littered with cans or a turtle entangled in plastic. Beach and underwater cleanups organized by local communities and dive shops are like trashy scavenger hunts for a very good cause — and the ocean’s not the only place to get involved.

“We find all kinds of things,” says Cora Lennert of Keep Austin Beautiful, which organizes an annual underwater cleanup at Lake Travis that’s the biggest such event in Texas. “There’s typical lake trash like beers cans, bottles, lots of Solo cups and coozies,” she says, “But also beach toys, sunglasses, tires, mattresses — last year we found the headlight of a riding lawnmower.”

The 2012 event saw more than 400 divers participating with 950 volunteers in total, with 3.6 tons of litter removed, a full 2.6 tons of which was recycled. If you can’t find a cleanup in your local area, you can always spearhead something small and focused of your own.

When to Go Sept. 15 on Lake Travis (keepaustinbeautiful.org/underwater); or get involved with Project AWARE to learn about or help organize a cleanup near you (projectaware.org).

Next Page: Scooter Races

SCOOTER RACES

Anyone who’s ever gotten his hands on a diver propulsion vehicle has felt the rush of that extra kick of speed thrusting him through the water.

“You see guys who’ve been diving 40 years come out of the water screaming like schoolgirls,” says Joe Weatherby, co-founder of the Wreck Racing League. “For cruising around at a blistering 3 to 4 miles per hour, you can’t believe how much fun it is.”

The league organizes the annual Weeki Wachee Warrior Challenge at the Florida springhead to honor wounded veterans. The event is staged in Weeki Wachee’s famed mermaid arena, so spectators can watch the underwater action (and hear it too — an underwater announcer calls the action, play by play). Bring your own scooter and you’ll be entered into a competitive category based on the power of your machine to race around the circular “track.” Plan to settle in for a weekend of topside fun too, with live music and parties rounding things out.

When to Go Sept. 20 to 22, at Weeki Wachee Springs, Florida (wreckracingleague.com).

Next Page: Fish Counts

FISH COUNTS

One fish, two fish, red fish, blue fish. It’s a bit more focused when you’re taking an underwater tally of the species around you on your dive slate, all in the name of helping scientists better understand local fish populations. Consider it fish-spotting for a purpose — reports gathered by fish-count participants deliver useful information about fish biodiversity and abundance.

REEF’s Great Annual Fish Count is organized every July by local REEF partners all over North America and the Caribbean, with REEF representatives on hand to instruct divers on carrying out surveys and identifying species of particular local interest. Divers and snorkelers can participate, and fish-identification seminars leading up to the events ensure you know what to look for. The aim is to pinpoint as many species as possible on each dive or snorkel, so look everywhere — under ledges, into the water column and out in the blue. You never know what you’ll find.

When to Go The Great Annual Fish Count is held every July in various locations, but you can tally reports every time you dive and submit them to REEF; visit fishcount.org for more. The New England Aquarium Dive Club is organizing fish counts on July 13 at dive sites around Halibut Point State Park in Massachusetts (neadc.org/gafc).

Next Page: More Upcoming Events

DIVE IN!

Got an underwater event to share? Drop us a line and we’ll list your events on scubadiving.com. Email us at edit@scubadiving.com.

Pumpkin Carving, Oct. 26, ****Bellingham, Washington

** **Bring your own unadulterated pumpkin — pretracing and precarving is a cardinal sin — for the underwater pumpkin-carving contest at Fairhaven Marine Park with gonediving.org.

Christmas Tree Decorating, Dec. 14, Dania Beach, Florida

Members of the South Florida Divers scuba club have an annual tradition of decorating a tree sunk just off the Dania Beach Pier with shrimp, scallops and other tasty fish treats. Book a seat on they day's dive and participate (sfdi.com).

Santa Sits, Dec. 7 and 14 Sport Chalet Scuba locations in California, Nevada and Arizona

Bring your scuba and noncertified friends along (ages 10 and up are welcome) to pose underwater with Santa in a pool setting at various West Coast Sport Chalet shops (blog.sport chalet.com).

Easter Egg Hunt, 
April 19, 2014 Maui, Hawaii

** **More than 70 divers take to
the waters at Keawakapu Beach for a
shore dive on the Saturday before Easter to search for plastic eggs — filled with sand and water but marked for prizes (mauidreamsdiveco.com).

Safari Hunt, ****May 4, 2014 Wrightsville Beach, North Carolina

** **Scour the 400-foot-long wreck of the liberty ship off Wrightsville Beach for numbered tokens that let you draw from a hat for $4,000 worth of dive-related prizes (aquaticsafaris.com).