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Author: Jennifer Forman Orth

Invading your brain since 2002.

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Monday, May 20, 2002

The Purple Pages

The Purple Loosestrife Project, sponsored by Michigan State University, aims to control Purple loosestrife in Michigan (Lythrum salicaria) through the introduction of loosestrife-eating beetles from Europe. But rather than just focusing on applying biological controls, the PLP encourages public involvement through education and school-sponsored projects. Their site has many activities and lessons for the K-12 crowd, plus general information about the value of wetlands and the problems caused by Purple loosestrife invasion.

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Sunday, May 19, 2002

Lettuce Aphid Update

In an update to a story I posted last week, the Ministery of Agriculture and Fisheries in New Zealand has announced that it will not try to contain the spread of the Lettuce Aphid (Nasonovia ribis-nigri) that was discovered in and around the area of Christchurch. The decision was made due to the difficulties and high cost of eradicating the species. Farmers are being informed about the aphid but apparently will not be given any financial assistance to deal with infestations.

Saturday, May 18, 2002

Palm Beach Plant Perils

A while ago, Palm Beach County in Florida came close to instituting a very strict policy regarding the introduction of dozens of invasive and potentially invasive plants. Due to a move by the Florida state legislature superceding the Palm Beach ruling, their list is instead restricted to a few of the worst invaders. Removal of the species from Palm Beach County property is required as each of nine species are added to the banned list over the next decade.

One major problem with this is that species on the list are the most well-known and populous invaders. It's a lot easier and cheaper to avoid introducing non-native species, vs. removing established ones. Landowners are starting to raise concerns about the ruling, wondering how they will be able to afford to remove big shrubs and trees such as Melaleuca quinquenervia from their property. I wish Palm Beach County the best of luck, but I have doubts as to whether they'll ever be able to rid their land of those big bad invasives.

Friday, May 17, 2002

Dust Devils

From the May/June issue of the journal American Scientist come this article about microrganisms, chemicals and inorganic particles that travel across the globe in dust. The above link goes to an abstract rather than the full story, but there's a nice set of related web links at the bottom of that page. Some people would not consider arrival of bacteria or fungal spores in this manner as an invasion, since it occurred without the aid of humans. But the reality is that you could probably find a human aspect to all environmental problems, sometimes in the most indirect ways. (To be fair, dust storms can also have positive effects on the environment as well.)

(Thanks to a member of the ALIENS-L listserver for posting the link to this story.)

Thursday, May 16, 2002


The headline says it all: "New Jersey declares war on Canada Geese." The saga of the Canada Goose (Branta canadensis) is an interesting one. The species was once quite rare, but now populations have expanded to the point where the geese are now unwelcome guests in many parts of the U.S. In large quantities, their waste can pollute bodies of water and is an unsightly mess in grassy areas. An additional problem is that some geese have altered their migratory patterns to overwinter in cities, becoming a year-round issue.

Canada Geese have of course been introduced into Europe and the U.K., where they are causing similar problems and winning similar affections from people. As a response to unwanted geese, various inventions have sprung up to combat local goose "infestations." My favorite one is the RoboGoose (the video is a must-see!).

Garlic Mustard Explosion?

Garlic Mustard (Alliaria petiolata)

Can't find much in the news on invasive species today, so I'm making my own...

In my travels this spring around Quincy, Massachusetts, I've noticed that there seems to have been an massive expansion of Garlic mustard populations (Alliaria petiolata). I have to keep reminding my self that this species is a biennial, so if it's catching my eye everywhere because it's in flower, then the expansion actually occurred last season.


Tuesday, May 14, 2002

What comes around, goes around

I thought I was keeping tabs on the Spartina invasion on the west coast, but it turns out I didn't have the whole story. I knew that the east coast native Salt marsh cordgrass (S. alterniflora) was causing problems, invading mudflats and turning them into salt marshes, and pollen swamping the west coast's Pacific cordgrass (S. foliosa). The species was introduced to the west coast accidentally (via shipments of oysters) and intentionally. It has also devastated the U.K., hybridizing with Small cordgrass (S. maritima) to produce offspring, Townsend's cordgrass (S. townsendii), that is a better competitor than either of its parents.

Now it turns out that English cordgrass (S. anglica) is also invading the west coast of the U.S. More interesting is the fact that neither Small cordgrass nor English cordgrass are actually native to the U.K. For now, the west coast is focusing on a study of how best to manage English cordgrass.

Monday, May 13, 2002

Waging War on Weeds

According to the Environment News Service, the Australian government has just pledged $3 million dollars ($5.6 Australian dollars) to fight 5 of their top 20 worst weeds. The weeds to be targeted, all non-native introductions, are: Blackberry (Rubus fruticosus), Chilean needle grass (Nassella neesiana), Gorse (Ulex europaeus), Lantana (Lantana camara), and Serrated tussock (Nassella trichotoma). Australia has always been at the forefront of invasive species management and research. Unfortunately, the extent of these invasions means they are fighting an uphill battle.

Note to news services everywhere: let's get some scientific names in these articles! "Blackberry" doesn't give me nearly enough information.

Sunday, May 12, 2002

Attack of the Aphids

In parts of New Zealand, restaurants and other businesses in the food industry have had to throw away tons of lettuce since April, due to infestation by the appropriately named Lettuce Aphid (Nasonovia ribis-nigri). The is the first mention I've seen of this aphid in New Zealand, though parts of the western U.S., including California, have also had problems with infestations over the past several years. Lettuce aphids are suspected to be native to the northern hemisphere. The current fear in New Zealand is that the invasion will spread to plant species in the genus Ribes, since they are the preferred hosts on which the aphids lay their eggs.

Saturday, May 11, 2002

A Smut Fungus Among Us?

The people at Grist Magazine, who are light years ahead of me in the art of corny headline design, have an article on their website called "More Internet Smut." No, not that kind of smut. It's about a smut fungus, and a team of researchers at the USDA Forest Service Shrub Lab that are trying to develop it as a biocontrol for cheatgrass (Bromus tectorum). Cheatgrass has caused major problems, both economically and ecologically, since it began its invasion of the west coast. Robert S. Devine's book, Alien Invasion: America�s Battle with Non-Native Animals and Plants has an excellent chapter on cheatgrass invasion in the U.S.

(Note: this article was posted over 2 years ago, not sure why the Grist included it in their newsletter Friday. If this work is still going on, there's no information about it on the internet.)

Friday, May 10, 2002

Alaskan Atlantic Salmon?

A report from the Anchorage Daily News today details the story behind last year's catch of an Atlantic Alaska. I'm not sure why they waited a full year before breaking this story. Apparently Atlantic salmon (Salmo salar) have been considered a threat to Alaskan and Canadian fisheries for some time. There is concern that the introductions, most likely accidental ones from saltwater fish farms, will lead to decreases in populations of native fish and other sport fish. Ironic considering the projects currently underway to preserve populations of this species on the Atlantic coast.

This reminds me a lot of the story of the introduction of the nutria (Myocastor coypus), a South American rodent, to the southeastern U.S. It seems like no matter how careful people are, there should always be a contingency plan for when the introduced critters escape, because they always do. But perhaps my view is biased because I never hear stories about the ones that don't escape...anyone?

Thursday, May 09, 2002

Animal Invasions

The online version of "E - The Environmental Magazine" has a story in the May/June issue about invasive species. It's a well-written piece that focuses on animals, and has what is possibly the cutest photo I've ever seen of a feral hog (the endangered species look good too :-). If you're not familiar with the issues surrounding invasive animals, this article is a good introduction. There are a few references in the article to an excellent "layman's" book on the subject of invasive species, Kim Todd's Tinkering with Eden, if you prefer book-learning to web-learning.

(Thanks to a member of the ALIENS-L listserver for posting the link to this story.)

British Oaks in Danger from American Fungus

Since the mid-1990's, the west coast has been losing oak trees to "sudden oak death," a disease caused by the fungus Phytophthora ramorum. According to the Environment News Service, Britain, which has a history of importing and growing American plant species, has found the fungus on a few viburnum plants, and is trying to avoid a more widespread problem. Their response: a ban on the import of certain trees and woody shrubs originating from America, including some wood products.

Wednesday, May 08, 2002

Buzz Kill

In the latest issue of the journal Austral Ecology is an article (link is to abstract) about the invasion of the large earth bumblebee (Bombus terrestris) into Tasmania and nearby mainland Australia. This species is one among several non-native bees in that region competing with native bees for food. Conflicts arise because at the same time, they are valued by farmers and others who depend on pollinators for economic reasons. Click here to see a pdf file with a brief history of bumblebee introduction in Australia (and a nice identification guide).

Update 5/26/04: Thanks to Jenny L. for sending a link to this interesting article that speculates about exotic bumblebee impact in Australia. The Aussie Bee website is definitely the place to go when you need info about any bee sighted in Australia.

Monday, May 06, 2002

Icy Reception

According to this article in the L.A. Times, the Iceplant (Carpobrotus edulis, Hottentot fig) is getting a bit more attention in California, which is already dealing with huge problems caused by invasive plants like Scotch Broom (Cytisus scoparius) and Cheatgrass (Bromus tectorum). Iceplants in California have been found to displace native species (some of them rare or endangered) that provide habitat and food sources for native animals and insects (sometimes endangered themselves). Because the Iceplant, native to South Africa, is only a problem in certain coastal habitats, and is already so widespread, there has been resistance from the nursery industry against banning its sale as an ornamental.

Sunday, May 05, 2002

Frog Blog

MSNBC has a story about the Coqui (Eleutherodactylus coqui) situation in Hawaii. These tiny frogs are native to Puerto Rico, and were accidentally (and probably intentionally) introduced into Hawaii during the 1990s. Hawaii has no native reptiles or amphibians, and the Coqui has quickly become a major competitor for insectivorous birds.

The eradication techniques listed in the article are pretty interesting. One involves spraying the frogs with a massive blast of caffeine, causing them to die a horrible, twitchy death. Another involves applying lime to dry the frogs out. Officials admit that they wish they had dealt with the Coqui when the frogs were first spotted in Hawaii, but even now delays in permits and funding continue.

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Saturday, May 04, 2002

Saguaro Under Siege

Populations of Saguaro cactus (Carnegiea gigantea) in Arizona are in decline, and according to this story from the Environment News Service, researchers suspect that invading populations of the African species Buffelgrass (Cenchrus ciliaris, Pennisetum ciliare) are at least partially to blame. Buffelgrass, introduced to America as a forage grass for grazing animals, increases the size and frequency of fires in the areas it invades, and Saguaro have been noted to disappear from burned regions of habitat. This spring, scientists from the USGS are beginning an investigation in Arizona to determine the best way to remove Buffelgrass and to gauge the recovery of native species.

Friday, May 03, 2002

Trouble in Lake Victoria

The largest body of fresh water in Africa, Lake Victoria, is in trouble, according to researchers. Among the threats to the lake's ecosystem (and the livelihood of many people) are exotic species introductions. The South America Water Hyacinth (Eichhornia crassipes) has become so invasive that populations were mechanically shredded several years ago in an attempt to prevent further spread. In addition, the introduction of non-native fish species as food sources has led to dramatic and unpredictable fluctuations in all fish populations, and also to government imposed bans on fishing. The combination of these threats with siltation and water pollution has led all involved parties to worry that a precious resource is in irreversible decline.

Wednesday, May 01, 2002

Why couldn't they have brought Koalas too?

Sometime during the Gold Rush, around 1855 or so, the first Eucalyptus trees were introduced to California from Australia. In 1999, 144 years later, the red gum lerp psyllids (Glycaspis brimblecombei) were first found in California, followed by the spotted lerp psyllids in 2000. Eucalypts are valued trees in California, and probably feel like a natural part of the landscape to many. The Australian psyllids are insects that have infected and destroyed thousands of trees, and have even caused problems for birds that were feeding on the sugary substance produced by the insects. The red gum lerp psyllid has also been found in Florida.

Now Californians are fighting back against these insects, also known as "jumping plant lice." Introduction of a wasp as a biological control has not remedied the situation fast enough for some. The L.A. Times reports that the latest psyllid-fighting weapon is a tiny pesticide capsule, inserted in a hole drilled in an infected tree, that releases chemicals that kill the psyllids.

Tuesday, April 30, 2002

Fleeing the Fleas

Tiny crustaceans known as Spiny Water Fleas (Bythotrephes cederstroemi) are annoying fishermen and worrying environmentalists in Canada and the Great Lakes region. This freshwater species, introduced from Europe and fairly recently discovered in North America, establishes huge populations that are physically disturbed by the dragging of fishing lines. The result is fishing gear covered with a slimy, smelly mess, and the potential of the species being spread in this manner to even more water sources. Another recent Canadian article discusses the negative impacts that this invasion could have on the vacation/real estate markets.

Sunday, April 28, 2002

Christmas Trees

Today I went to pickup my tree seedling from the Quincy Public Works Department. The city has an "Evergreen Program", which I think is a great idea: you drop off your Christmas tree to be recycled, and they give you a coupon to pick up a baby tree in the spring. They're planning on planting 12,000 trees in the city. The letter I received promised me a Bracted Balsam Fir (Abies balsamea), which is native. Unfortunately, when I got home I realized my seedling was a Norway Spruce (Picea abies). It's ironic to me that most of Europe has been reforested with American tree species over the past few centuries, and now we're growing and planting European trees here. While Norway Spruce is not considered invasive in the U.S., it is on the "watch lists" of some groups studying invasive species, and has been identified as a problem species in Canada.

Saturday, April 27, 2002

Trashing the South Pole

People are still ironing out the definitions used in invasive species ecology. Specifically, what constitutes an "invasive" species is a subject of contention among scientists and policy makers alike. Some contend that an invasive species has to have been introduced by humans, either accidentally or intentionally.

Of the species that are naturally dispersing into new habitats on a regular basis, there are very few that can do so on a continental scale. (One example that comes to mind is the Sea Beans, a group of plants whose water-dispersed seeds can cross oceans.) Now comes this story from the BBC about marine creatures hitchiking across the ocean on trash. For thousands of years, organisms like mollusks and corals have attached to natural debris that floats on ocean currents. But now surveys show that more than half of the debris found near the Antarctic is man-made. Not only is there a lot more debris than is natural, but it is even easier for organisms to survive on the more-durable artificial materials. So, if one of these species starts spreading aggressively, is it invasive or not? (Story tip from The Daily Grist)

Friday, April 26, 2002

Pike on the run

In California, the Department of Fish and Game has found a better way to deal with introduced freshwater fish than poisoning entire bodies of water...they're blowing the fish up!! The northern pike (Esox lucius) introduced to Lake Davis are aggressive predators, and have taken over the lake. After a previous attempt at poisoning the fish affected water quality, caused health problems, and prevented all fishing for months, Fish and Game has turned to a less toxic option. Explosions are set off underwater and dead fish are then scooped off the surface. If the detonations turn out to significantly harm the trout that also inhabit the lake, officials will look into other management options.

Though this method is obviously one of control rather than eradication, it makes sense in this situation. Since the pike were reintroduced intentionally after the lake was cleared the first time, it is likely introductions will continue to occur. Northern pike is a popular game fish, and though it has been introduced by humans to many lakes, its range is considered circumarboreal. You can read more about the effects of northern pike introduction in this .pdf file. (Thanks to a member of the ALIENS-L listserver for posting the link to this story.)

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Thursday, April 25, 2002

Beetle Battle

In an effort to fight the spread of the Asian Longhorned Beetle, New York will be enlisting the aid of fancy new acoustic devices that detect the noises beetle larvae make as they chew their way through tree trunks. The acoustic sensors, which attach directly to the trees, will be accompanied by a wide-scale insecticide treatment program.

Wednesday, April 24, 2002

Shoo Fly?

Used to considering fruit flies as a household and office pest (my office being adjacent to biological labs), I was surprised to read this story in the New York Times about a non-native species causing problems in the western U.S. (NYT requires a user name and password). It turns out that there are many native species of fruit flies whose populations have been in decline since the arrival of Drosophila subobscura, a European native. Unfortunately native Drosophila suffer from a lack of attention due mostly to the fact that they're, well, flies. If you don't want to deal with logging in to the NYT, you can read a similar article from 2000 from the Seattle Post Intellingencer. For more detailed information, check out this book, though it might be in German.

Tuesday, April 23, 2002

"You took off like a Jetbead..." (Okay, no one's going to get that obscure Brit pop reference, I know.)

A member of the Yahoo! group ma-eppc posted requesting reports on Jetbead sightings. Known by the scientific name Rhodotypos scandens, this shrub should now be coming into flower, though it is probably easier to identify once it has developed its distinctive 4-fruited clusters. Often planted as an ornamental, this Asian native is being monitored in several eastern states due to reports of its escape from cultivation.

Monday, April 22, 2002

Upcoming Global Biodiversity Forum to include invasive species workshop

The first Global Biodiversity Forum for the Pacific region will be held in the Cook Islands this July. One of the three workshops they are convening is entitled "Invasive Species in the Pacific: Strategies for Countering the Threats." The deadline for submitting abstracts is May 31. General information about the conference can be found here. To find out about past sessions of hosted by the multi-institutional GBF, click here.

Sunday, April 21, 2002

New Zealand snails in California

According to this undated story from the ESPN Outdoors website (yes, that ESPN), the New Zealand mud snail (Potamopyrgus antipodarum) has been found in California. Previously seen in rivers in Idaho and Montana, this tiny snail is prolific and very difficult to kill. This is a decent, fact-filled, environmentally-conscious article, with pointers for fishermen on how to avoid spreading this and other invasive species.

Researchers are not exactly sure how the New Zealand mud snail was introduced, although likely vectors include ships' ballast and imports of gamefish (as eggs or adults). Work continues to measure potential effects of introduced mud snail populations, with initial studies suggesting they contribute to the decline of native aquatic invertebrates.

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