Friday, August 31, 2007
Last week I met up with some folks from Friends of the Blue Hills (FBH) to help plan a cleanup day they've scheduled at Eliot Tower. Eliot Tower is an observation tower located at the top of Great Blue Hill in the Blue Hills Reservation in southeastern Massachusetts. It's at an elevation of about 635ft and affords an excellent view of the surroundings.
Since the Reservation is state-owned property, FBH needed to coordinate their cleanup efforts with the Massachusetts Department of Conservation and Recreation. Eliot Tower is a historic building so the Friends are fairly limited in what they can do to fix things up. One of the possibilities was the removal of invasive plants, and I was asked to assess the site for possible management opportunities.
I knew beforehand that two common invaders were there: black swallowwort (Cynanchum louiseae) and Asiatic bittersweet (Celastrus orbiculatus). Upon arriving at the Tower (okay, fine, upon catching my breath following a steep climb!) I did a quick survey of the area. The wall around the building was dotted with Asiatic bittersweet, black swallowwort, and a bunch of other native and introduced plants:
That seemed manageable! Adjacent to the tower were a few picnic tables, and next to that was more black swallowwort:
Those patches didn't seem that bad, and there was a nice population of native blue curls (Trichostema dichotomum) right nearby - it would be good to get rid of the invader there!
The Massachusetts Natural Heritage & Endangered Species Program classifies the area around Eliot Tower as Acidic Rocky Summit. There is no real canopy there, just a lot of exposed rock and some herbs, grasses and shrubby things where the soil is found. It's dry, too, as you can probably tell from the photos - the black swallowwort is looking pretty wilty. Around the margins of the rocky open area is a mixed oak/hickory forest, with some cherry trees along the very edge:
This still didn't look that bad, if the black swallowwort was just along the edge of the forest canopy. Then I turned to my right, and the true extent of the black swallowwort invasion began to take shape:
The vine has almost completely taken over the forest understory! It reaches back as far as the eye can see in the shot above. It also dominates the edges of the trail shown here:
I am not sure when black swallowwort first arrived on Great Blue Hill, but it looks like it is there to stay, for now anyway. I feel particularly bad for these two false Solomon's seal plants (Maianthemum racemosa), holding on for dear life in a sea of swallowwort (while the swallowwort holds on to them!):
It is sad to see this part of the Blue Hills Reservation lose so much of its character. Gone are most of the goldenrods, asters, and other native herbs, replaced by a monotonous view of a single, invasive species.
So what do you tell a group of volunteers eager to help clean up a site like this?
A management plan to combat black swallowwort around Eliot Tower would need to go far beyond teams periodically hand-pulling the vines. For now, Friends of the Blue Hills will likely just focus their efforts on improving the physical aspects of the site (cleaning up trash and other tasks). While they could take this opportunity to do some outreach and remove the invasive plants from the perimeter of the building, but there is no practical way to prevent the black swallowwort from reinvading when it is so pervasive in the surrounding habitat. Prognosis: not good...unless you're black swallowwort.
Labels: Massachusetts, plants, vines
Thursday, August 30, 2007
Crab And Go
CBC News is reporting that the European green crab (Carcinus maenas) was discovered last week off the coast of Newfoundland, Canada. This is the first record for that province and marks the most northern point for the distribution of this marine invader on the Atlantic coast of North America. The discovery was made, of course, by fishermen, who noticed multiple green crabs in Placentia Bay. Perhaps the best nugget of information from the article, for me anyway, is that fishermen refer to the green crab as "cockroach of the sea" :-). More information is available from this article at cnews.
Labels: Canada, crabs, crustaceans, marine
Wednesday, August 29, 2007
Robin Hood And His Merry Moths
Sherwood Forest, one of several purported homes of Robin of Loxley (Robin Hood), is currently under threat by not one, but two different introduced moth species. According to this report at BBC News, the oak processionary moth (Thaumetopoea processionea) and the brown tail moth (Euproctis chrysorrhoea), introductions from Europe, are now both established in England. Biologists are quite concerned about the potential impact on the ancient oaks of Sherwood Forest if the moths arrive there. There is an attempt underway to manage the brown tail moth populations in nearby locations using pheremone traps...not sure what they're doing about the processionary moths though.
Thanks to biosparite for sending in a link to this story.
Labels: England, insects, moths, UK
Tuesday, August 28, 2007
The headline of this ABC News Australia story just about says it all: "Cat stew legal, may not be safe." Apparently someone in Australia submitted a recipe for cat stew in a local "bush food" cooking competition, and it's causing a bit of an uproar. The article might seem to suggest that eating cats is dangerous, but as one expert notes, it is not much different than eating any other wild animal. Is eating cat legal in your country?
Be sure to click on the audio link ("It's a nice sweet meat, not gamey like a rabbit") to get the full report. Thanks to members of the ALIENS-L listserver for posting about this story.
Labels: animals, Australia, feral cats
Monday, August 27, 2007
Like A Bull In A China Wetland?
This one is too interesting to wait for the next "New In The Literature" post...While trolling Science Direct for articles today, I came across this abstract:
"Inter-specific competition: Spartina alterniflora is replacing previous Spartina anglica in coastal China." 2007. Zhi et al. Estuarine, Coastal and Shelf Science. 74(3): 437-448.
Wow - Spartina alterniflora (smooth cord grass) really gets around, doesn't it? Native to the east coast of the U.S., this grass has traveled far and wide, invading wetlands from the west coast of the U.S. to the U.K. and all the way to the Far East. In China, where S. alterniflora
arrived in the 1970s, the species is now replacing Spartina anglica
, an invasive cousin whose populations have been notably dwindling since the 1990s. The study shows that S. alterniflora
is outcompeting S. anglica
in almost every physiological way: biomass, height, roots, leaf area...the list goes on and on. The older invader could be getting pushed right out of its niche.
Unfortunately, you're stuck with just the abstract of this article unless you or your library has a subscription to Estuarine, Coastal and Shelf Science...or you can click on the little envelope by the author's name and ask for a reprint.
Labels: China, grass, plants
Sunday, August 26, 2007
Weekend Blog Blogging
The past week in invasive species news, from other people's point of view:
Labels: birds, Florida, Hawaii, Malaysia, plants, weekend blog blogging
Jumping (non-native) carp in Wisconsin.
Thanks to Jibby7 for sharing this photo under a Creative Commons license!
Labels: Flickr, photoblogging
ISW Podcast, Episode 5
Episode 5 of the ISW Podcast is now available for your listening pleasure. It covers August 6-12, and probably contains at least 2 million occurrences of the phrase "invasive species" :-).
If you wish to make the podcast a more permanent part of your life, you can subscribe to the feed or subscribe via iTunes.
Friday, August 24, 2007
Plenty More Fish In The Sea
The Cuban News Agency is reporting that two lionfish (Pterois volitans) were recently captured in the waters off of Cuba's central-north coast, near Villa Clara. This is apparently the first known occurrence of this Indo-Pacific species in Cuban waters, though lionfish have been showing up all over the Atlantic lately.
The lionfish were captured and placed in a holding tank, whereupon they immediately demanded mojitos and medianoches in exchange for their further cooperation.
Labels: Cuba, fish, marine
Thursday, August 23, 2007
Southern California Public Radio (KPCC 89.3FM) recently did a three-part feature on the aquatic invasive species that impact their part of the world. Part 1 is about the recent discovery of quagga mussels, Part 2 investigates marine invaders and ballast water management, and Part 3 is about the negative impact of fish hatcheries on the region's native flora and fauna. The best part is that you get to pick your flavor of information retrieval - play the audio or peruse the full text of the transcripts if you prefer. There are lots of interesting photos too - good stuff!
Labels: California, fish, fishing, mollusks, mussels, quagga mussels
Wednesday, August 22, 2007
Hawke's Bay Today is reporting
that a man in New Zealand is alleged to have threatened to release the nasty invasive alga known as didymo (Didymosphenia geminata, also known as "rock snot") into the Waiau River. He reportedly called in the threat to the Wairoa Department of Conservation in response to their plans to begin poisoning local populations of rats and possums. Charges are expected to be brought against him, though a search of his house did not turn up any of the offending invader.
If he is found guilty, he could get 5 years in jail or a fine of $100,000 NZD (about $70,000 US). Personally, I'd rather he got one of those cool activist judges who punishes him not with jail time, but with something innovative. Like, say, a dunk tank filled with didymo...or stationing him at a boat launch and making him clean off anglers' boots with a toothbrush ;-).
Labels: algae, didymo, New Zealand
Tuesday, August 21, 2007
New in the Literature
Long overdue list of recently published journal articles about invasive species:
- "Invasive range expansion by the Humboldt squid, Dosidicus gigas, in the eastern North Pacific" by Louis D. Zeidberg, and Bruce H. Robison. Proceedings of the National Academy of Sciences. 104(31), pp. 12498-12950. (Weird, is that a typo of Zoidberg?)
- "Reduced plant–soil feedback of plant species expanding their range as compared to natives" by ROY H. A. VAN GRUNSVEN, WIM H. VAN DER PUTTEN, T. MARTIJN BEZEMER, WIL L. M. TAMIS, FRANK BERENDSE, ELMAR M. VEENENDAAL. Journal of Ecology. 95(5), pp. 1050-1057. (Just one of several interesting articles in that volume's Invasion Ecology section!)
- "Invasive plants and their ecological strategies: prediction and explanation of woody plant invasion in New England" by Patrick M. Herron, Christopher T. Martine, Andrew M. Latimer, Stacey A. Leicht-Young. Diversity and Distributions. 13(5), pp. 633-644. (In yet another invasives-filled issue!)
- "Abundance, species richness and feeding preferences of introduced molluscs in native grasslands of Victoria, Australia" by KELLY D. HOLLAND, MARK J. MCDONNELL, NICHOLAS S. G. WILLIAMS. Austral Ecology. 32(6), pp. 626-634.
- " Productivity alters the scale dependence of the diversity-invasibility relationship." by Kendi F. Davies, Susan Harrison, Hugh D. Safford, Joshua H. Viers. Ecology. 88(8), pp. 1940-1947. (California grasslands)
- "Dissecting the evolutionary impacts of plant invasions: bugs and beetles as native guides" by SCOTT P. CARROLL, CHARLES W. FOX. Global Change Biology. 13(8), pp. 1644–1657.
- "Disturbance, invasion and re-invasion: managing the weed-shaped hole in disturbed ecosystems" by Yvonne M. Buckley, Benjamin M. Bolker, Mark Rees. Ecology Letters. 10(9), pp. 809-817.
- Also, be sure to check out 22(9) of Trends in Ecology & Evolution, which has a special Focus on Biological Invasions. Too many interesting review articles to list them all here!
Monday, August 20, 2007
The CBC Radio One show "Sounds Like Canada" is having a cool Photoshop contest to see who can mock up the best example of Canada's worst weeds taking over in some "iconic Canadian scene." Their example is a version of Parliament Hill covered by Canada thistle, an invasive plant that, despite its common name, is native to Eurasia.
There doesn't seem to be any prize but the brief shot at fame, but that's okay. Think you can beat their examples? If you want to have a go at the contest, you can download their starter photo here (or use your own, but remember this is supposed to be about *Canada*). Email the results to soundslikecanada AT cbc.ca. You can also use that email address to nominate what you think is Canada's Worst Weed.
Thanks to a member of the Yahoo! group ma-eppc for posting about the contest.
Labels: Canada, contest, photoblogging, plants
Sunday, August 19, 2007
ISW Podcast, Episode 4
Episode 4 of the Invasive Species Weblog Podcast is now available for downloading. It covers stories featured on the ISW from July 30-August 5.
Part of an impressive patch of mile-a-minute vine (Polygonum perfoliatum
) in Pennsylvania. Hmm...not sure this vine grows in any way other than "impressive"...
Thanks to fyrefiend for posting this photo under a Creative Commons license.
Labels: Flickr, Pennsylvania, photoblogging, plants, vines
Friday, August 17, 2007
U-M News is reporting that researchers at the University of Michigan may have found the key to how round gobies (Neogobius melanostomus) managed to spread so quickly through the Great Lakes. Round gobies are typically bottom-dwellers, which would make it difficult for them to get sucked into ballast water, since ships typically take on ballast near the top of the water column. Now a new study has discovered that when the gobies first hatch, the tiny larvae rise to the surface of the water at night, to find food and presumably evade predators, and then descend again in the morning. The new insight into round goby behavior also provides an insight into how ships become a vector for this invasive fish species.
Interested readers can find the abstract to the original research article here, but to see the full version you'll need a subscription to the Journal of Great Lakes Research. Thanks to John R. from Don Watcher for sending in a link to the story.
Labels: animals, fish, Great Lakes
Thursday, August 16, 2007
The U.S. Environmental Protection Agency recently released a draft report about climate change and aquatic invaders called "Effects of Climate Change on Aquatic Invasive Species and Implications for Management and Research" The 70-page document is aimed at those who assess and manage aquatic resources in order to provide them with information about the potential impacts that climate change could have on invasive species found in both aquatic and wetland ecosystems. It includes a state-by-state review of whether climate change is being taken into account when developing management strategies for aquatic invasive species and identifies gaps in information available to managers.
There is a public comment period for the document in effect until September 10, 2007. If you've got something to say about it, head over to here (search by Document ID: EPA-HQ-ORD-2007-0666).
Labels: aquatic plants, climate change, legalese
Wednesday, August 15, 2007
Fuel For Fools?
YAIB (Yet Another Invasive Biofuel) might just have to become a recurring feature at the ISW: Green Energy News is pondering whether the Barbados nut (Jatropha curcas) might be our next big source of biodiesel. Oil extracted from the seeds of this species has been found to be a good source of fuel, and now plantations are being developed all over the world. The problem is, as it seems to be with most of the species targeted as biofuel, is that Barbados nut, native to the Caribbean, is a known invasive in several countries, including Australia, and its use in Western Australia is banned. Is this really a species we want to start planting all over the place? Kind of takes the "friendly" out of "environmentally friendly" fuel alternative, doesn't it?
Interested readers will want to check out this article in the American Chronicle, this one from the Kruger Times, and this one from Grain, and to ponder themselves why Jatropha is suddenly getting so much press?
Labels: biofuel, jatropha, plants
Tuesday, August 14, 2007
Fun With YouTube
More bizarre invasive species videos from the world of YouTube:
- Kentucky Afield posted a really interesting video about Bow fishing at night for bighead carp. Not for the squeamish, but if you want to see guys shoot an arrow through the head of a 40 pound carp with a bow and a flashlight, check it out!
- The Mississippi Valley Conservancy has a video about invasive plants. The intro is a bit heavy on the cheese, but on the whole, the video is full of good information.
- dancohen posts Alien Invasion, an educational video put together by some Emerson boys for a class project. It's wicked pissah! (No, no, it's not, it's actually pretty bad. Sorry guys. At least you had some decent factoids in there. But if you could get Rachel Dratch and Jimmy Fallon to parody it: comedy gold!) If you cannot get enough of them with AI Part 1, there's always AI Part 2, which is an interpretive dance. [Via That Biology Girl]
- Flkitesurfer caught a lionfish hanging around a shipwreck in the Bahamas. WOuld be a nice diving video, except for the fact that lionfish are native to the Pacific Ocean!
- bluedotprodux posted a video showing feral goats being removed from Santa Cruz Island, in the Galapagos. I have no idea what the guy being interviewed is saying, but I do know that it cannot be fun to be charged with catching and dragging dozens of goats into a truck.
Labels: animals, carp, education, feral goats, fish, fishing, Galapagos, island, outreach, plants, video, youtube
Sunday, August 12, 2007
Weekend Blog Blogging
The past week in invasive species blogging:
Labels: animals, birds, garlic mustard, mute swan, plants, tamarisk, weekend blog blogging
Saturday, August 11, 2007
Amazing photo showing a microscopic view of the floating vegetation of the invasive aquatic plant water hyacinth (Eichhornia crassipes
Thanks to longan drink for sharing the photo under a Creative Commons license.
Labels: aquatic plants, microscopy, photoblogging, plants
Friday, August 10, 2007
The Donegal News is reporting that the aquatic invasive plant known as African curly weed (Lagarosiphon major) has been found in yet another county in Ireland. African curly weed has been known in that country since the 1960s, but until recently there were no records for County Donegal (on the northern tip). While the discovery was made in a garden pond, it is thought that the weed is widespread and likely to enter natural habitats. Surprisingly, though this species is already known to have infested water bodies across Ireland, and in one lake has spread over more than two dozen acres, it is still available for sale as a pond plant in that country.
Bonus points to the Donegal News for using the plant's scientific name.
Labels: aquatic plants, Ireland, plants
Thursday, August 09, 2007
The Daily Journal is reporting that wild parsnip (Pastinaca sativa) is an up-and-coming plant invader in the state of Minnesota. While no one was paying much attention, it managed to work its way into the landscape, and now it is popping up along roadsides in such numbers that biologists across the state are fielding calls about it.
Wild parsnip is in the carrot family, and is kind of like a kid brother of the related Giant Hogweed (Heracleum mantegazzianum). Unfortunately, while it is of much smaller stature, it still packs that poisonous punch of a nasty sap that blisters the skin when exposed to sunlight. Yech.
Bonus points to the Daily Journal for using the plant's scientific name.
Labels: Minnesota, plants
Wednesday, August 08, 2007
DNA = Detect Nefarious Algae
ScienceAlert is reporting that a group of researchers at the University of Waikato in New Zealand have developed a "rock snot detection kit" that tests for the presence of the invasive alga didymo (Didymosphenia geminata, also known as "rock snot"). Using molecular tools, the scientists can detect didymo in concentrations of one cell/ml or less. I believe, if the protocol is the same as this presentation by the same scientists, that they have developed genetic markers for didymo and can run samples through PCR amplification to check for a match.
A tool like this would be quite useful for early detection monitoring, since didymo is most likely to spread into a new area long before it can be detected by the human eye. In fact, US researchers will probably want to get a copy of these markers to see if they match the recent didymo discoveries in the Northeast! Now if I could just find a paper published on the subject, so that I know this is not a recycled story from talks given on the subject in 2006.
Labels: algae, didymo, genetics, New Zealand
Tuesday, August 07, 2007
New Zealanders might be happy to know that a graduate student is on his way to developing a biocontrol agent to deal with white-tailed spiders (Lampona murina and L. cylindrata). According to this story from stuff.co.nz, Nic Cummings discovered a fungus that kills the spiders, and is now attempting to grow it and hopefully tame it so that it can be placed in traps. White-tail spiders are originally from Australia, and were introduced to New Zealand over a century ago. While they are not venomous, their bite can transfer a bacteria that causes skin to erupt in a rash or even nasty blisters.
Labels: biological control, fungi, New Zealand, spiders
Monday, August 06, 2007
Neither Here Nor There
Native or not? New research by a team of scientists has called into question the idea that the common periwinkle (Littorina littorea) has been living on the Atlantic Coast of North America for the past 8000 years. While previous genetic studies had concluded that this was the case, a new study says there is actually lots of genetic variation in North American populations that was not explained by the European snails that were sampled. Coupled with the fact that the two "winkle" shells (hey, that's what they call them in the UK) that supposedly dated back to the time of the Vikings have now gone missing, it now seems possible that later European introductions of the snail could have led to its spread along the coasts of the US and Canada. While one author of the previous study seems to have switched sides, this still a contentious issue...the Nature story alludes to a response by one of the dissenters but I can't find a link yet. Sounds like they need to do some more sampling!
You can read more about it at Nature's News site, or track down the full articles:
Chapman, J.W., Carlton, J.T., Bellinger, M.R. and Blakeslee, A.M.H. 2007. "Premature refutation of a human-mediated marine species introduction: the case history of the marine snail Littorina littorea in the Northwestern Atlantic." Biological Invasions.
Wares, J.P., Goldwater, D.S., Kong, B.Y., and Cunningham, C.W. "Refuting a controversial case of a human-mediated marine species introduction." 2002. Ecology Letters. 5: 577-584.
Labels: marine, mollusks, snails
Sunday, August 05, 2007
ISW Podcast, Episode 3
Episode 3 of the ISW Podcast is now available for your listening pleasure, featuring blog posts from July 20-29. Audio quality slightly improved over Eps 1 and 2, though the whole thing might be spoiled by the ridiculous number of times I say "invasive species" :-). You can catch archived podcast episodes over at the ISW Podcast blog, subscribe to the feed or subscribe via iTunes.
Weekend Blog Blogging
The past week in invasive species posts:
- PAgent is feeling a little forgiving of the invasive blackberry plants (I'm assuming Himalayan) now that they are giving up bucketfuls of ripe fruit.
- Invasive Plants in Arlington posts about hacking away at wineberry, wintercreeper, vinca and Japanese stiltgrass. Go, Invasives Man!
- b from Iowa takes a strong stance with invasive carp...a really strong stance :-).
- In case you cannot make the next meeting of the National Invasive Species Council Advisory Committee, the Invasive Notes blog invites you to post any comments you wish to be passed along.
If you post about any invasive species-related issues and would like to be featured in the Weekend Blog Blogging post, drop me an email (use the Suggest a Post link in the top left corner). It's getting harder and harder to wade through the splogs that have invaded the blog search engines :-).
Labels: animals, carp, fish, Iowa, legalese, plants, Virginia, weekend blog blogging
Friday, August 03, 2007
Caddo = Can Do!
Back in February of this year, the ISW posted about efforts to protect Caddo Lake in Texas from the invasive aquatic plant known as giant salvinia (Salvinia molesta). Flash forward to July 30th, when biosparite sent in a link to a New York Times article about the very same lake...and holy cow! They've managed to wrangle some serious support for what originally seemed to me to be a low-level grassroots effort. First, they got Don Henley, former Eagle and enviro-champion extraordinaire, to voice his concerns for the current state of the lake (turns out Don actually keeps a trailer on the lake). There's already a Caddo Lake Institute established by Henley and friends that predates the salvinia invasion. Then, concerned citizens raised $35,000 to purchase a giant net (two miles wide!) to isolate the more salvinia-ridden portions of the lake. Now, this past week, the Texas legislature appropriated over $200,000 for controlling salvinia in the lake. We're talking some serious advocacy here, no?
This tiny post really can't do the NYT artlce justice, so do head over there to read the full story. Thanks biosparite!
Labels: aquatic plants, plants, salvinia, Texas
Thursday, August 02, 2007
An interesting article appeared in the Baltimore Sun a few days ago that is causing some buzz in the usual invasive species circles. In it, USGS scientist Nancy Rybicki talks about hydrilla (Hydrilla verticillata) and other invasive species in the Potomac River from the angle of how they benefit the ecosystem.
Back in the 1970s, the Potomac was quite polluted. With flows of sewage and phosphorus pollution cut off by the 1980s, things began to look up. It was around that time that hydrilla was first discovered in the river. Along with Eurasian water milfoil (Myriophyllum spicatum), hydrilla now provides food for birds and nesting habit for crabs and fish. Nancy notes that biodiversity levels in the Potomac are good regardless of the fact that there is a mix of native and non-native species.
The article was almost certainly inspired by a study Nancy recently published with Jurate Landwehr in the journal Limnology and Oceanography, "Long-term changes in abundance and diversity of macrophyte and waterfowl populations in an estuary with exotic macrophytes and improving water quality." (full pdf, or read the USGS press release here). Covering 17 years of data, the study found that the amount of native and non-native aquatic plants were actually increasing together over time, i.e. the invaders did not completely take over the way people were concerned they would. However, the research does point out that non-native plants were the dominant components of the habitat. That doesn't seem to be as strong of a conclusion as the newspaper article is making (hydrilla as a savior - yeesh).
If the only goal is to manage the Potomac for waterfowl habitat, then we might be able to say they're doing a good job. Looking at the health of the ecosystem as a whole, it is hard to predict what it would be like if the non-native plants, invertebrates and fish were not there. This raises some interesting questions that no one can easily answer: Could native plants have better filled the niche to provide habitat for fish and fowl? Will the ability of the native plants to grow eventually be impeded by hydrilla? What is the impact on aquatic insect communities in a habitat dominated by non-native plants? And perhaps most importantly, what is the impact on neighboring bodies of water to let hydrilla thrive in the Potomac? A plant so easily spread by boaters and waterfowl surely isn't staying put in a single river.
Labels: aquatic plants, Maryland, plants