Invasive Weeds
When you’re outside, look out for the Giant Hogweed, an invasive weed that is infecting gardens and can cause blisters, burns with permanent scars, or even blindness. The Giant Hogweed’s sap consists of photosensitive chemicals that turn toxic when exposed to sunlight. The weed is found predominantly in moist areas and grows to be as much as six metres tall with a white flower head. Currently, local health officials are teaming up with biologists in an effort to control this weed, officially known as the Heracleum mantegazzianum, reported the Province.
The Giant Hogweed is most often found next to roadsides, ditch-lines, river banks, creeks and agricultural areas. It is found across the continent. The Invasive Plant Council of British Columbia states that the plant has recently been found in southern Vancouver Island, the lower mainland, Squamish and the Fraser Valley. Reports of the Giant Hogweed are on the rise.
If you happen to spot the Giant Hogweed, please report it to your provincial weeds hotline – in BC, it’s at 1-888-WEEDSBC. Hogweed clearing should be done by an expert wearing waterproof gloves, a rubber raincoat and pants and eye protection, reports the Toronto Sun.
The Giant Hogweed is prolific – in a single season a healthy plant can produce as many as 100,000 seeds. The seeds get spread around through wind and water, and the plant is crowding out native plants.
Invasive Weeds are a problem everywhere, it seems. California just had their annual “Invasive Weed Awareness Week”. Groups such as the Lake County Weed Management Area hosted various events including the Area’s fifth annual invasive weeds tour, summarized by Lake County News. The tour planned to discuss weeds including the Arundo donax, tree of heaven, water primrose, tamarisk, and the skeleton weed, and various other aquatic weeds.
Conquering Invasive Species
Scientists are using some creative ways to get rid of invasive species that threaten other animals, plants, and even entire ecosystems, reports Scientific American.
Hawaii has about 20 types of non-native algae, two of which are especially destructive, grow quickly, and destroy the coral and reef diversity. When volunteers removing the algae by hand failed to keep pace with the algae, scientists started using a “Super Sucker” – a vacuum with a 100-foot hose that can remove up to 360 kilograms of algae every hour from the reef.
Asian carp, with their voracious appetite, have been found in the Illinois River, which connects the Mississippi River to Lake Michigan, says the EPA. Since 2004, the EPA has worked with several other organizations to install and maintain electric barriers to stop the carp from advancing. Perhaps efforts should also target the carps’ skittishness, their only known weakness. When they hear a sound such as a boat motor, the carp jump out of the water, thereby granting, at least in my mind, an opportunity to spear, shoot, net, or somehow kill/capture them.
Sometimes the solution is in the invader’s new environment. When baby Cane Toads meet a meat-eating ant, the toads just freeze. In Australia, cat food is used to attract the ants to a certain pond, and in a test study the ants attacked 98% of the toads. 70% of the baby toads died.
Occasionally invasive species can provide a useful service. Hawaiian and Galápagos Island vegetation is being stripped by unrestrained goats. Meanwhile, a Puget Sound business is “renting” out a herd of goats to consume voracious invasive plants including the English Ivy, Scotch Broom, Himalayan Blackberry, and Japanese Knotweed. A herd of 120 goats can clear an acre in 6 to 14 days, depending on how dense the brush is.
Elsewhere, the U.S. Department of Agriculture uses dogs to sniff out Brown Tree Snakes from crates in Guam which are heading for other islands. Since the snake’s arrival, nine native Guam bird species have disappeared, and the two remaining species are nearing extinction. The snakes also bite humans and cause frequent small blackouts. Perhaps the dogs should be used in the forests as well.
It’s great to read that scientists are using some creative methods to win the battle over invasive species. In time, more such solutions will be thought up, hopefully in time to save native species that are being threatened by the invaders.
Tags: algae, Asian Carp, Australia, Brown tree snake, cane toad, dogs, EPA, Galapagos, goats, Great Lakes, Guam, Hawaii, invasive, meat eating ant, Scientific American, species, Super Sucker, US Department of Agriculture
Eating An Invader: Lionfish
In the wild, lionfish are greedy predators that have invaded the Caribbean and eastern US seacoast. They gobble up native fish and damage ecosystems, and can mean the end of local economies based on snorkeling and diving tourism dollars.
But there’s hope. Apparently lionfish taste great, and efforts are being made to develop a market in which humans can eat lionfish into local extinction in the areas it doesn’t belong.
Sea to Table is a New York based organization which seeks out locally and sustainably managed fisheries needing better access to direct markets and provides a direct connection between fishermen and chefs. In a recent interview, Sean Dimin of Sea to Table told me about the high level of interest that was shown when lionfish was made available in several restaurants in the test markets of New York and Chicago. “With a few boxes and plenty of conversations around the country, we feel there is a large enough market to tackle this problem,” Dimin commented.
That lionfish tastes delicious is a large success factor. Although it could be sold through a conservation story, people would only go so far in supporting the effort if the taste wasn’t there. But the lionfish feeds on small crustaceans and fish, and has a similar taste to snapper. The delicate, snow white flesh has an almost sweet flavor.
Now that the market has been found, Sea to Table is working on creating a reliable supply. The challenge is that conventional harvesting methods, such as hooks and lines, don’t work. Lionfish are top predators, not scavengers which might feed on already dead animals such as bait in a fish trap. Sea to Table has been working with National Oceanic and Atmospheric Administration (NOAA) off the coast of North Carolina, as well as with a number of dive outfits, to try to find a solution. One method that works is using live bait. When live bait fish are put into a 2 litre soda bottle and then placed into a fish trap, the lionfish think it’s a school of small fish and enter the trap, becoming trapped themselves. The live bait can be used again and again, unlike dead bait.
Dimin also mentioned “the largest of the fish processors in the Bahamas are working to develop traps and are also working on putting bounties out there for spear fishermen to go and harvest” as many lionfish as possible. Bounties were used previously but became too expensive to maintain when the number of lionfish exceeded the budget. But bounties become affordable when paid by a fish processing plant that sells the fish. “It’s a commercialization of directed overfishing”, suggests Dimin.
So if a reliable supply can be obtained, human appetites for healthy and delicious foods might just eat this menacing species out of existence in the areas it causes harm. It looks like this invasive species story is heading towards a deliciously happy ending.
