Seaweeding

Hawaii is dealing with invasions of several different species of seaweed (marine algae), according to this article from the Honolulu Advertiser. It's getting so bad that over the past six months, volunteers have removed more than 20 tons of Gracilaria salicornia from Waikiki reef, but they still don't have the upper hand. There are actually five major invasive seaweeds, also known as limu, threatening the coasts of Hawaii. You can read about them in detail at the Alien and Invasive Algae in Hawaii web site, created by Jennifer Smith, a grad student who spearheaded the seaweed removal efforts. Here's a link to an older article on the subject.

A long way from home

There's an Associated Press article appearing in several newspapers today about a flock of tropical parrots that make their home in Seward Park (Seattle, Washington). The article doesn't even mention what species of parrot they are, but after a bit of sleuthing I found this blurb which says the parrots, native to Peru, are either Chapman's mitred conures (Aratinga mitrata alticola) or scarlet-fronted conures (Aratinga wagleri frontata). Both are kept as pets, though it is unclear whether the flock is the result of an accidental escape, or abandonment by the former owner. This article has more information about the flock, made up of about 10 parrots, which have been in the park for over a decade.

Messing with Texas, and more...

A few good articles have shown up today:

• From the Environment News Service, details of a report just released by the Union of Concerned Scientists, outlining the impact of invasive species on the state of Texas.
• Also from ENS, this report about a study in the journal Ecology. Results of the study indicate that areas subject to frequent flooding have more non-native plants. You can read the abstract here.
• From BBC News, this article about the economic and ecological costs of non-native species introduced into Africa. One perspective not mentioned in the article is the potential usefulness of some of the invasives, like water hyacinth (Eichhornia crassipes). You can read the full press release from the World Conservation Union (IUCN), which produced an educational booklet on the subject, by clicking here (.pdf file).
• Finally, from the journal Nature, two short articles about the enemy release hypothesis, demonstrating that non-native organisms tend to have fewer "enemies" associated with them when compared to native species. One article is about plant pathogens (fungi, smut and the like), the other is about parasites on animals. You'll need a subscription (or a library with one) to read more than the first paragraph.

Thanks to members of the ALIENS-L listerserver and Woody for providing information about these articles.

Purple Loosestrife Patrol

I just added a hat to my Invasive Species Weblog store. If you're out releasing beetles or cutting and pulling purple loosestrife (Lythrum salicaria) this summer, you'll want to be wearing one of these!

Take Action Now!

The Union of Concerned Scientists sent out a "Sound Science Initiative" alert today about the need for co-sponsors for the National Aquatic Invasive Species Act, due to be introduced to Congress in a week or so. They are asking members of their network of scientists to call their senators and representatives to urge them to sign on. You can read and send a form letter to your Congresspeople by clicking here. You don't even need to know their names, the form determines it by your zip code (Note that there does not appear to be any preview, the email is just sent without confirming it with you, so be careful if you change anything!)

Britain Bombarded by Invasive Plants

A recent study by the non-profit UK group Plantlife indicates that the invasion of non-native plants into Britain has been more successful than most people would expect. According to this article at Guardian Unlimited, the study divided Britain into over 3000 squares of land, and 82% of those blocks contained at least one of the top fifteen invasive plants. Interestingly, while some of the top species, like Japanese knotweed (Fallopia japonica), were introduced over a century ago, there are also successful invaders like Australian swamp stonecrop (Crassula helmsii, also known as New Zealand pygmy weed), which needed only 50 years to get to the top of the list, and floating pennywort (Hydrocotyle ranunculoides), which has only been in the UK since around 1990.

Plans for Lake Austin frozen, temporarily

Looks like the plan to release grass carp (Ctenopharyngodon idella) into Lake Austin, to fight the invasive aquatic plant hydrilla (Hydrilla verticillata), has been put on hold. According to this article from News 8 Austin, a Texas judge granted a two-week restraining order preventing the release. Before the two weeks are up, he will hear from a group of bass fishermen ("S.M.A.R.T.") protesting the release, as well as from state workers who support it. The fishermen are concerned that the grass carp will not limit themselves to eating hydrilla, making them a threat to all the vegetation in Lake Austin. The article has links to full coverage of the Lake Austin saga at the bottom of the page. You can also browse two other blog entries on the subject by clicking here.

Thanks to a member of the ALIENS-L listerserver for posting a link to this article.