Invasive species
awild | February 23, 2009From my inbox, a postdoctoral job announcement:
The Department of Botany, La Trobe University, Melbourne, Australia seeks to appoint a Postdoctoral Fellow to conduct research in Invasion Biology on Christmas Island. Over the last decade, supercolonies of the invasive yellow crazy ant Anoplolepis gracilipes have spread across island rainforest and caused a variety of significant impacts. High ant densities are consistently associated with high densities of exotic honeydew-secreting scale insects. This project will determine the dependence of ant supercolonies on associated scale insects…
awild | February 21, 2009The port at Mobile, Alabama, photographed from across the bay.
The port city of Mobile, Alabama holds special significance for students of ant science. Jo-anne and I took a weekend trip down to the gulf coast in January, and as we are both myrmecologists we felt compelled to stop and take a few photographs. Not only is Mobile the childhood home of ant guru E. O. Wilson, but the city's docks have been the point of introduction into North America for some notorious pest ants. We'd have neglected our intellectual heritage to just drive through.
Mobile's busy international commerce has…
awild | February 10, 2009 There's been a debate simmering among Argentine Ant researchers about the difference between the ant's ecology in its native South America and in the introduced populations. The heart of the disagreement is this: is the introduced Argentine ant dominant because its biology changed during introduction, or because the ecologies of the native and introduced ranges are different?
Like most scientific debates, some aspects are factual in nature while others are semantic. Sometimes the semantic and the factual become confused in a way that makes it difficult to tease the arguments apart…
jwhitfield | February 6, 2009Back when I started this, I remarked that one of the reasons I hadn't read the Origin was that I couldn't imagine it being essential to a grasp of contemporary science. Regarding evolution, I think you could still make a case for this. But in other ways, that statement shows that you really shouldn't opine on topics you know nothing about.
Specifically, I'm talking about ecology (by which, just to be clear, I mean the study of the interactions of living things with each other and their environment, rather than 'nature' or 'environmentalism'). It's been said that all European philosophy is a…
awild | January 29, 2009Pheidole moerens, major worker, Louisiana
Pheidole moerens is a small, barely noticeable insect that travels about with human commerce, arriving without announcement and slipping quietly into the leaf litter and potted plants about town.  As introduced ants go, P. moerens is timid and innocuous- it's certainly no fire ant. The species is now present in the southeastern United States, a few places along the west coast, and Hawaii. Conventional wisdom suggests that P. moerens originated in the Greater Antilles, but even though the ant was first described from Puerto Rico a century ago…
edyong | January 17, 2009
Bee hives, with their regularly arranged honeycombs and permanently busy workers may seem like the picture of order. But look closer, and hives are often abuzz with secret codes, eavesdropping spies and deadly alliances.
African honeybees are victimised by the parasitic small hive beetle. The beetles move through beehives eating combs, stealing honey and generally making a mess. But at worst, they are a minor pest, for the bees have a way of dealing with them.
They imprison the intruders in the bowels of the hive and carefully remove any eggs they find. In turn, the beetle sometimes fools…
edyong | December 20, 2008
Miners used to take canaries into unfamiliar shafts to act as early warning systems for the presence of poisons. Today, climate scientists have their own canaries - amphibians. Amphibians - the frogs, toads and salamanders - are particularly susceptible to environmental changes because of their fondness for water, and their porous absorbent skins. They are usually the first to feel the impact of environmental changes.
And feel it they have. They are one of the most threatened groups of animals and one in three species currently faces extinction. The beautiful golden toad (right) was one of…
awild | December 16, 2008This just in: Eli Sarnat's "Pacific Invasive Ants" website is up. It's got something for everyone: fact sheets, videos, keys, links.  Eli's got an eye for design, too, so the site is aesthetically pleasing and easy to navigate.
http://www.lucidcentral.org/keys/v3/PIAkey/index.html
(postscript: yeah, yeah. Pacific Disturbance Specialist Ants. I know.)
awild | December 9, 2008Solenopsis invicta - invasive or just disturbed?
Prevailing wisdom holds that imported fire ants marched across the southern United States on the virtue of their fierce nature and superior competitive ability. The fire ant conquest of the south reads like a tale of bravery and intrigue, but according to Walt Tschinkel and Josh King it is also not true.  They have a must-read study in PNAS this week detailing a tight set of field experiments that turns the conventional wisdom upside-down.
King and Tschinkel disturbed various patches of native Florida pine forest by mowing or plowing,…
edyong | November 29, 2008
As Charles Darwin learned several centuries ago, islands are havens for evolution. Newcomers to these isolated worlds find themselves unshackled from the predators that dogged them on the mainland. They celebrate their freedom by diversifying into a great variety of species. But predators still have ways of tracking them down, and following the footsteps of sailors is one of them. By killing adults and eating eggs, introduced predators such as rats, cats and stoats are responsible for nine in ten of the bird extinctions since 1600.
Now, conservation agencies are getting serious about…
edyong | November 21, 2008Over the past decade, some coastal waters have started turning red with alarming frequency. The cause is not some Biblical plague, but dense concentrations of microscopic algae called dinoflagellates. Red tides can often contain more than a million of these cells in a mere millilitre of water. Many are harmless and essential parts of the ocean environment, but others produce toxins that can kill local wildlife and risk the health of humans who eat their poisoned flesh.
These "harmful algal blooms" are more common in warm waters that mix poorly and are unusually rich in nutrients. Their…
grrlscientist | November 12, 2008tags: ecology, exotic species, introduced species, non-native species, invasive species, monk parakeets, quaker parrots, Myiopsitta monachus, Michael A Russello, Michael L Avery, Timothy F Wright
Monk (Quaker) parakeets, Myiopsitta monachus, with nest.
Image: Arthur Grosset [larger view].
Invasive species are everywhere: from plants such as Scotch (English) broom, Cytisus scoparius, whose yellow flowers bloom prolifically along roadways of North America, Australia and New Zealand to mammals such as human beings, Homo sapiens, which are the ultimate invasive species because we have…
awild | October 27, 2008
Jim Wetterer has a paper out in Myrmecological News detailing the global spread of the ghost ant Tapinoma melanocephalum. This diminutive dolichoderine is quite possibly the most widely distributed ant in the world, a hitchhiker on human globalization, thriving in the wake of human-wrought ecological destruction. Their cosmopolitan dominance reflects our own.
Oddly enough, we still don't even know where they originally lived.
Ghost Ants - photo by Picasa user Aimeric
citation: Wetterer, J. K. 2008. Worldwide spread of the ghost ant Tapinoma melanocephalum (Hymenoptera: Formicidae). …
edyong | September 20, 2008
The decades that make up a typical human lifespan can seem like vast stretches of time to us. But to the forces of evolution, they are mere temporary blips. Common wisdom has it that evolution occurs over geological timescales - thousands and millions of years. As such, evolutionary biology takes a lot of criticism for being a 'descriptive science', being less open than other fields to that fundamental aspect of science - experimentation. Though there are exceptions, those who study evolution must mostly be content to observe snapshots of life, either present or entombed in rock, and make…
awild | September 17, 2008Platythyrea pilosula - Image by April Nobile/Antweb
Yesterday, the above photograph was uploaded to Antweb's databases.  Platythyrea pilosula is the final species to be imaged for the Ants of Paraguay project, marking the end of a sporadic and meandering study that I started in 1995 as a hobby during my stint in the Peace Corps. After combining several years' worth of my field collections with the holdings at 19 entomological museums, I tallied 541 species for the country. This turns out to be too many species to keep track of in my head (I max out at about 300 or so), so I've found…
awild | May 27, 2008
As if we didn't already have enough pest ants to worry about, here is a relatively new one. The rover ant Brachymyrmex patagonicus, a tiny South American species, has been working its way under the radar across the southern United States. Its presence is now large enough that pest control companies are reporting a sudden increase in requests. According to gardeners I've talked to, these ants emerged in huge numbers here in Tucson about 5 years ago. Given the interest in this species, I thought I'd post a summary of what we know of this emerging pest and how to reliably identify it.…
awild | May 21, 2008Scott Solomon, who researches fungus-growing ants, has a brief piece in Slate Magazine on the Paratrechina Crazy Ants invading Houston.
I'm not convinced that this ant is anything different from Paratrechina fulva, a common South American species and the oldest name in that species complex. People have been calling the Houston invader "P. cf. pubens", but the taxonomy of the genus is so poor that it's difficult to say anything with confidence. Do you folks who've looked at specimens (that's you, James) have any thoughts about the identity of this ant?
awild | April 29, 2008
If you're having trouble filling that bare wall over your desk, the Bohart Museum of Entomology has just the thing: a new line of insect posters. The invasive ant poster above was designed by Fran Keller from auto-montage images by Eli Sarnat, Jasmine Joseph, and Anna Lam.
awild | April 13, 2008
The Argentine Ant (Linepithema humile), a small brown ant about 2-3mm long, is one of the world's most damaging insects. This pernicious ant is spreading to warmer regions around the world from its natal habitat along South America's Paraná River. Linepithema humile can drive native arthropods to extinction, instigating changes that ripple through ecosystems. In California, horned lizard populations plummet. In South Africa, plant reproduction is disrupted. Worldwide, the Argentine ant is a persistent house and crop pest. This is not a good ant.
My Ph.D. dissertation, completed a few…
awild | March 9, 2008
Strumigenys louisianae stalking a springtail
Tucson, Arizona
Non-native species should make a naturalist's skin crawl, but these ornate little trap-jaw ants are a guilty pleasure. Strumigenys louisianae is among the most widespread of the miniature trap-jaw ants, occurring naturally from the southeastern U.S. to northern Argentina. The desert climate in Tucson is too dry for Strumigenys, but they persist in lawns, gardens, and other places in town where irrigation raises the moisture levels. No one knows when or how they arrived, but it is likely the founding colonies stowed away in…