DLNR’s New Plan for Invasive Species: Eat the Invaders

The Hawaii Department of Land and Natural Resources (DLNR) has started an innovative and unusual campaign to rid Maui of one of the fastest-growing invasive species, the Red Swamp Crayfish. According to the DLNR, the crayfish eats crops, damages land, kills native species, are easy to catch, and are absolutely delicious. They are counting on the stomachs of hungry Hawaiians to do what years of chemical control efforts couldn’t hold the crustaceans in check.

Like so many of Hawaii’s invasive species, the story of the Red Swamp Crayfish, Procambarus clarkii, is one of unintended consequences. Introduced into taro patches near Ahuimanu Stream in O’ahu, the crayfish population exploded and became a serious threat to taro cultivation. The pests have been documented to consume taro, and rice, prey on insects, snails, and the eggs of native fish species. If that wasn’t bad enough, their burrows can cause bank erosion along streams and rivers, as well as drain taro fields.

With the help of tourists and collectors, the crayfish soon found their way to other islands, Maui in particular. Chemical controls over the past few years have proved ineffective at slowing down the population, and many are concerned about the use of potentially dangerous chemicals inside the preservation zone. After it was discovered that SSHAM affected the crustacean’s nervous system, many local streams were “chummed” with the canned meat product in an attempt to kill them off. However, the practice was stopped out of concerns about the long-term consequences on native species. “To be honest we were running out of ideas,” says the DLNR’s Greg Iona. “It was a trip to Louisiana by one of our officers that sparked the consumption campaign. We’re focused on getting the word out about the crayfish and letting people know that there is a great new seafood option right out their backdoor. They really are easy to catch, and quite delicious when prepared correctly.”

The State’s campaign highlights the abundance of crayfish in many streams around Lahaina and offers an open season on the pests. The DLNR provides cooking and catching tips on their website, as well as information regarding the damage caused by the species every year. Many local businesses are jumping on board, with local eateries offering crayfish dishes, and SSHAM CEO Art Pua’a saying the company plans on offering a clarkii blend within the next month. Nonetheless, not everyone is sold on eating the pests.

Hula Noodle owner Ralph Umeke says the crayfish will never be offered in his noodle shop. “They call them mudbugs for a reason,” he says. According to Umeke the crustaceans are foul-tasting and potentially dangerous.

“They’ve been putting a lot of pressure on restaurant owners to help promote this idea of theirs. They’ve even offered to provide the crayfish for the first few months for free, but I just can’t do it in good conscience. I’m not sure I have the words to describe what one of these things taste like. They’re awful. There isn’t enough garlic, butter, or rum in the world to make them edible. Imagine finding a pool that hasn’t been cared for in a couple years, drain it and wipe up the scum on the bottom with a piece of bread, that’s close. The first one I tried made me retch. Not only do they taste bad, but they are potentially dangerous. After doing a little research, I found that they have a propensity to accumulate environmental contaminants like: heavy metals, dangerous organic runoff compounds, and pesticides. They can also be vectors for several harmful human parasites including: the lung fluke, rat lungworm, and leptospirosis bacteria. I think trapping them is fine, but I wouldn’t put one in my mouth.”

The DLNR says that like many animals, crayfish living in polluted waters can be dangerous, but the water quality on the island makes them safe to eat. Despite what Umeke may think, they encourage the public to give the crayfish a try. Many are doing just that. Over the past weeks, crayfish fever has hit the island, and many businesses are cashing in. The Kokua Wellness Center is touting a line of crayfish-infused tonics and fresh fruit drinks.

Spokesperson Yvonne Masters says, “We are excited to offer a large variety of clarkii collagen infused health drinks. These natural healing tonics are perfect for: weight loss, boosting immunity, increasing bone density, and enhancing the skin. We use only local crayfish, blend them onsite, and extract the collagen fresh every day to maximize flavor and potency. We are recommending the drinks to our clients as a supportive health aid, to be used in conjunction with their usual Newuskin treatments.”

Rather than consumption, local inventor Ano Lee is focusing on catching the crayfish. Even though Lee himself recently battled a life-threatening leptospirosis infection, one of the pathogens found in the species, he says he is excited about the open season and has designed a unique trap perfect for catching buckets full.

“The pyramid-style trap, with three entrance funnels has been the industry standard for a long time because it is nearly perfect for its intended purpose. My design is similar, with adjustable funnels so it can be used on a variety of crustaceans including crabs, and spiny lobster, but that isn’t what sets my traps apart. It’s the sonic lure, that makes the difference with our traps. Most crustacean fishing is passive with scent lures designed to draw in your intended targets, but my traps send out a continuous low frequency pulse that calls out to the crayfish, and draws them in. I’m not sure if it’s an aggression or a sex thing, but they sure come running when they hear the noise.”

Lee disregards complaints that the sound produced by his traps has caused pets to become agitated, and reports that they have led to insomnia, unusual dreams, and ringing in the ears in people living near an active trap. He says, “It’s springtime and it’s only natural that animals are going to be more vocal at this time of year. The same goes for people. Sometimes you have weird dreams and can’t sleep. It happens to everyone. It happens to me all the time. I would suggest that these people get some noise-canceling headphones if it bothers them that much, and look up some crayfish recipes because they are going to catch a ton with my traps.”