Conservation Biology » Biodiversity in Focus Blog

Home on the Range in the 21st Century

Biology, Cool Science, Diptera, Nature 1 Response »

Jun 242015

Oh give me a home where the buffalo roam,
Where the deer and the antelope play,
Where seldom is heard a discouraging word,
And the skies are not cloudy all day.

When it comes to evocative imagery of North American landscapes, perhaps no other song brings nature to life like Home on the Range. Sung round a campfire, your imagination can’t help but picture the Great American Plains teeming with life and big game under wide open skies as far as the eye can see. Yet, even as Dr. Brewster Higley was writing Home on the Range in 1876, the ecosystem that inspired him was already being drastically altered, and within a decade only a few hundred buffalo would roam where millions had previously.

And while buffalo, or more properly, bison, have largely been extirpated from their home on the range, they left behind an ecological footprint, if not hoofprints, that may influence the ways in which the deer and the antelope, but also the sheep, play.

When we think of animal engineers, we normally think of the beaver, reshaping waterways with dams and lodges carefully crafted with no regard for canoeists or property owners. But bison are known to wallow in their own environmental ingenuity as well, quite literally. Buffalo wallows are depressions in the plains that after decades of communal use by bison herds develop a layer of water-impermeable soil that helps trap water and mud near the surface, which in turn draws more and more wildlife to them during the hot, dry, summer months. These communal baths are even visible from space, and have stuck around for centuries even where bison no longer visit.

By rolling around and washing off all manner of biological material, from skin and hair to dust and plant matter, along with all manner of bodily fluids (bison aren’t adverse to peeing in the pool, so to speak), these wallows, when used, become highly enriched with organic matter. And where there are pools of organically-rich, wet, mud, there are undoubtedly a range of flies just waiting to make themselves at home.

Enter new research by Robert Pfannenstiel and Mark Ruder of the Arthropod-Borne Animal Diseases Research Unit of the USDA in Kansas. Pfannenstiel and Ruder wondered whether biting midge larvae (Ceratopogonidae) in the genus Culicoides were more likely to be found in wallows that haven’t been used for generations but which still collected water, or in wallows that rebounding bison have adopted and infused with fresh fertilizer.

When it comes to aquatic fly larvae associated with “Arthropod-Borne Animal Diseases”, Culicoides may not seem an obvious choice, with things like mosquitoes and black flies more often drawing our attention. But just as the megafauna of the Great Plains has changed since 1876, so too has its microfauna.

In the late 1940’s, a new disease began to emerge in the sheep and cattle of the Southwest, first in Texas, and then California. Termed “soremuzzle” by ranchers and shepherds, infected livestock, particularly sheep, would develop swelling and ulcers in and around their nose and mouth, become fevered, pull up lame, and in some extreme cases, the animal’s hooves would fall right off. Then, in 1952, immunologists finally put the pieces together and realized “soremuzzle” was actually Bluetongue Virus (BTV), a vector-borne disease only known from Africa and the Mediterranean at the time. Since then, Bluetongue Virus has spread from the American Southwest up throughout the plains and has begun creeping into the Midwest, as well as spreading to all the other sheep-inhabited continents, recently becoming a major concern for shepherds in the UK.

The wide spread of BTV was made possible in part by ranchers shipping infected sheep (which commonly don’t show signs of infection, and can remain infectious for weeks following initial exposure) around the globe, but also by the close relationships among the virus’ vectors, biting midges in the genus Culicoides. In the Mediterranean, the only vector had been Culicoides imicola, but eventually enough infected livestock spread into the neighbouring ranges of Culicoides obsoletus and C. pulicaris in Europe, who then helped spread the disease all across the continent.

Meanwhile, in North America, another pair of Culicoides species with wide ranges of their own found themselves home to BTV, Culicoides sonorensis, and Culicoides insignis, bringing us back to buffalo wallows and muddy waters.

Culicoides sonorensis – Photo copyright Adam Jewiss-Gaines, used with permission.

Pfannenstiel and Ruder scooped mud from buffalo wallows in and around the Konza Prairie Biological Station in Kansas (where, incidentally, the state song just so happens to be Home on the Range), some of which were currently being used by bison, and some of which had not been visited by bison for years, and reared the Culicoides larvae from each sample in the lab. They found that active bison wallows were home to Culicoides sonorensis (as well as several other closely related Culicoides species), with several dozen specimens reared from mud collected throughout the summer, while relict wallows were not.

All of this leads to an extremely complex conservation conundrum. By bringing back bison, and allowing them to resume wallowing in their wallows, it seems we’re increasing habitat for a fly species that carries a disease not present the last time bison roamed the range. Bison themselves are susceptible to BTV, but like cattle, don’t normally show the extreme symptoms or mortality that sheep do. However, the bison’s range is also home to nearly half of America’s sheep, with more than 2 million heads grazing the same areas as bison once roamed. More bison may equal more Culicoides, which in turn could equal more cases of BTV among livestock, a prospect that likely won’t sit well with ranchers and shepherds in the area.

What’s more, sheep aren’t even the most susceptible plains animals to BTV. While most infected sheep may show clinical signs of BTV infection, usually less than 30% of infected animals actually succumb to the disease. Meanwhile, the deer and the antelope (pronghorn) playing alongside the wallowing bison and grazing livestock experience an 80-90% mortality rate when infected with BTV, and will likely serve to spread the disease further, faster.

Of course, being a vector-borne disease, BTV can only spread as far as its vector is found, and unfortunately, we’ve been caught a little unprepared to answer just how far that may be. Culicoides are difficult to identify, and so we don’t know where these flies may or may not be found currently, and more importantly, where they may spread to in the future as climate change broadens acceptable habitat. Luckily, researchers like Adam Jewiss-Gaines, a PhD student at Brock University, are working to not only figure out where Culicoides‘ are found, but are also developing keys and resources that will allow others to track the great migration of these tiny flies.

Conservation biology is complicated, and fraught with trade-offs, especially when we try to conserve species in landscapes on which we place a high economic value and which we have changed immutably. So while we’ve brought bison from the brink of extinction back to Home on the Range-era levels, we now find ourselves presented with a new range of conservation challenges, and there may yet be dark clouds in our future skies.

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Pfannenstiel, R. S., and M. G. Ruder. 2015. Colonization of bison (Bison bison) wallows in a tallgrass prairie by Culicoides spp (Diptera: Ceratopogonidae). J. Vector Ecol. 40: 187–90.

Monikers Only Matter for Vertebrates

Blogosphere, Environment, Invertebrate, Taxonomy 6 Responses »

Jan 042015

In the latest issue of Scientific American, David Shiffman has a short article titled “Monikers Matter“, on the potential importance of common names for the conservation of species. He highlights the case of Charopa lafargei Vermeulen & Marzuki, a species of recently discovered snail only known from a single hill in Malaysia which is slated for demolition by the cement company Lafarge. He also cites a 2012 study by Paul Karaffa et al. that examined how student’s value animals based solely on (fictional) common names, and found that patriotic or “positive” names resulted in the students being more willing to conserve those species. It’s an interesting idea, and might be something for taxonomists to consider.

But, every species name put forward in Karaffa et al.’s study was either a mammal or a bird. Do we really think the same principles will apply for all species equally, specifically the uncharismatic invertebrates like insects, snails and their overwhelmingly diverse brethren?

There are 3 species listed as Endangered or Critically Endangered by the IUCN which have a common name that includes the term “American” (a term that features heavily in the positive section of Karaffa et al.’s survey), 2 of which are found in the USA (the 3rd is a Central American frog). Conveniently for this comparison, one is a vertebrate, the American Eel (Anguilla rostrata; listed as Endangered), and the other an invertebrate, the American Burying Beetle (Nicrophorus americanus; listed as Critically Endangered).

To estimate how much society values the conservation of these 2 species, I simply entered their scientific species names into Google Scholar and restricted the results to papers published in 2014, with the assumption that the number of people actively studying a species should act as a pretty good approximation for the value we place on that species as a society. In 2014, there were at least 456 papers published discussing the American Eel. In comparison, there were only 26 papers discussing the American Burying Beetle.

Obviously there is more at work here than just common names, but the fact that we value (by this simple metric at least) the American Eel so much more than the American Burying Beetle (a factor of 17.5x more) suggests that monikers don’t really matter, unless of course you share a spine with the species.

Vertebrate and charismatic bias is a significant influence in conservation biology, and nomenclature is unlikely to be an easy fix for it.

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Karaffa P.T. & E. C. M. Parsons (2012). What’s in a Name? Do Species’ Names Impact Student Support for Conservation?, Human Dimensions of Wildlife, 17 (4) 308-310. DOI: http://dx.doi.org/10.1080/10871209.2012.676708

Vermeulen J.J. & Marzuki M.E. (2014). ‘Charopa’ lafargei (Gastropoda, Pulmonata, Charopidae), a new, presumed narrowly endemic species from Peninsular Malaysia, Basteria, 78 (1-3) 31-34. DOI:

Insect Biodiversity: Unknown – a status report

Insects, Rant 7 Responses »

Dec 112014

Nature published an article this week with some nice infographics that illustrate the astonishing number of species considered threatened by the International Union for Conservation of Nature, which is pretty depressing, at least if you look at the vertebrates. In what was a nice surprise, they actually included data on insects in addition to the fuzzy wuzzy taxa, noting that there are currently 993 species of insects considered threatened by the IUCN.

993 species is quite a lot, right? I mean, mammals have 1,199 threatened species, and birds 1,373, so you’d be forgiven for thinking that insect conservation is actually not too far behind the curve. But what happens when you dig a little deeper into that data?

If I were to ask you what you thought the order of insects is with the highest number of IUCN listed species, I’d be willing to bet you’d guess moths and butterflies (Lepidoptera), or possibly beetles (Coleoptera). I know that’s what I assumed. I’ve prepared a few interactive graphs of my own to help break down what those 993 species are, and how they fit into the larger picture of insect diversity (hover over wedges to see percentages, and over taxon labels to find some of the smaller wedges). And surprise, it’s probably not what you were expecting.

That’s right, dragonflies, damselflies (the Odonata), grasshoppers, katydids, and crickets (the Orthoptera) together make up more than 50% of the 993 threatened insect species. Surprised?

Next, let’s examine the total number of species that have been assessed by the IUCN, which includes the 993 species listed as threatened, plus extinct species, species considered not at risk, and species where there is insufficient data to make any conclusions.

Somewhat unbelievably, 53% of all insects assessed by the IUCN belong to the Odonata. 53%. Talk about a massive skew in the data. For context, compare the IUCN’s assessment numbers to the total known diversity for each insect order.

Look at the relative sizes of the blue Odonata wedge and the red Orthoptera wedge across all three graphs: when we look across everything we know about insect diversity, 50% of IUCN threatened insects species belong to just two orders of insects, which together make up only 2.5% of the total insect diversity. Incredibly, nearly half of all known Odonata have been assessed by the IUCN. Compare that to some of the major orders (major both in the sense of diversity and ecological/economic impact), like flies (Diptera) where 8 (the Where’s Waldo slice of pie near the top of the Assessed Graph) out of the ~~150,000~~ 160,000 species we have names for have been formally assessed.

8 species of flies.

Out of ~~150,000~~ 160,000.

Wow.

What’s more, some other insect orders which you would think would be correlated to the high assessment numbers of mammals and birds, specifically their ectoparasitic lice (Pthithiraptera, here included in the Psocodea) and fleas (Siphonaptera), have been completely neglected, with only 1 louse and 0 flea species assessed. Granted not all ectoparasites have high host specificity (case in point, the Passenger Pigeon louse), but when you realize that conservationists working to save charismatic species like condors and black-footed ferrets have likely caused the extinction of their respective lice (none of which are included in the IUCN Red List by the way), and add in the fact that we’ve only described a tiny fraction of the total diversity of insects, we need to assume that the conservation status of insects is being dramatically, drastically, underestimated.

It certainly seems like conservation biologists have been preferentially looking at the bigger insects (Odonata, Orthoptera and Lepidoptera make up 75% of assessed species), and pretty much ignoring the rest. It’s hard to argue with that strategy considering how difficult it is to find, identify, and track smaller insects like beetles, flies and bugs, but if we want to give a proper status report on the state of global biodiversity, we have a lot of work left to do, and any interpretations involving insect diversity need to be taken with a goliath beetle-sized grain of salt.

And no, the goliath beetle, one of the largest insects alive today, hasn’t been assessed by the IUCN either. Go figure.

Of pigeons, extinction, and lice

Biology, Insects, Publication 5 Responses »

Sep 022014

Yesterday marked the 100^th anniversary of the extinction of one of our most iconic emblems, the Passenger Pigeon (Ectopistes migratorius). The web is alive with tributes to Martha, the final individual of her species, and cautionary tales of conservation and how we should be working to prevent this happening to any other species. There has also been considerable discussion and debate recently whether the Passenger Pigeon may be a candidate for “de-extinction”; the theoretical process of bringing a species back from the void through cloning and genetic engineering. Seeing how I generally dislike vertebrates dominating the biodiversity news cycle, I figured we could all use a slightly less depressing story about extinction, de-extinction, the role of natural history museums in conservation, and of course, taxonomy.

As we’re beginning to understand, no species is an island unto itself. Every individual is an ecosystem of parasites, predators and symbionts, and thus when one species disappears, its co-dependents are just as likely to vanish, usually without us even realizing it. Allow me to share the story of Columbicola extinctus, a chewing feather mite that quietly faded into the night likely years prior to Martha’s high-profile demise on September 1, 1914, and which we only learned about 20 years after that.

Columbicola columbae, a species closely related to Columbicola extinctus (it seems the differences between them are slight modifications of the head and genitalia; feel free to use your imagination). Photo by Vince Smith, used under CC-BY license.

Working from a preserved Passenger Pigeon specimen collected in 1895 and housed in the Illinois Natural History Survey, Richard Malcomson discovered and described Columbicola extinctus in 1937, noting he had only seen 15 specimens of this new louse. In what may be the saddest etymological discussion I’ve seen, Malcomson says:

“Dr. Ewing of the National Museum, Washington, D.C., suggested the name of extinctus which surely is a suitable one for the Passenger Pigeon is now extinct and probably has carried the parasite into extinction with it.”

And so humanity carried on, parading the Passenger Pigeon out as the flag-bearer for extinction, while its lowly louse faded from memory. That is, until 1999, when, like a phoenix louse rising from the ashes of its host, Columbicola extinctus out-lived its name. While reviewing the genus Columbicola, Dale Clayton and Roger Price discovered that Columbicola extinctus wasn’t found solely on the Passenger Pigeon, but was in fact still alive and well on the Passenger Pigeon’s closest living relative, the Band-tailed Pigeon (Patagioenas fasciata)! What’s more, Columbicola extinctus was found on Band-tailed Pigeon specimens collected all up and down the Pacific coast, from California to Peru! As Clayton & Price note

“Our study reveals no consistent differences between Columbicola specimens from the extinct passenger pigeon and those from the extant band-tailed pigeon, C. fasciata. Thus, there is no longer grounds for considering this species of louse extinct, despite its unfortunate specific epithet.”

It’s worth considering how bird specimens preserved and maintained in a natural history museum allowed taxonomists to not only find a species at a time when it was believed to be extinct, but to also resurrect that same species 60 years later, redefining the term “de-extinction” before it was trendy. Sure, Columbicola extinctus’ species epithet may be a little premature, but it also serves as an important reminder that while extinction is usually forever, nature sometimes finds a way.

And should someone ever succeed in bringing the Passenger Pigeon back from extinction (however unlikely that is or may be to occur), we’ll be able to reunite two species who’s lives and legacies were intimately intertwined, and who were each thought to be lost to time and humanity. A fairytale ending if ever I’ve heard, albeit one that probably won’t make it to Disney.

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Clayton D.H. & Price R.D. (1999). Taxonomy of New World Columbicola (Phthiraptera: Philopteridae) from the Columbiformes (Aves), with Descriptions of Five New Species, Annals of the Entomological Society of America, 92 (5) 675-685. DOI:

Malcolmson R.O. (1937). Two New Mallophaga, Annals of the Entomological Society of America, 30 (1) 53-56. DOI:

Beware: Irony Contained Within

Environment, For a Good Cause, Rant No Responses »

Jan 232014

Seeing how Canadian Prime Minister Stephen Harper has suddenly become a bastion for conservation biology, ornithology and science outreach with the announcement that a bird sanctuary has been named in his honour in Israel, I put together a little memento for him to hang in his office. Hopefully it will serve to remind him just how awesome birds and nature are, as long as they aren’t getting in the way of his Albertan oil field development plans, of course.

All kidding aside, the fact that another country thought that it was appropriate to bestow an honorary doctorate on and name a scientific research facility after a man who has been on a not-so-subtle campaign against scientific research & evidence-based policy making in Canada for the past 8 years is an absolute farce.

I guess in the end the joke is on me though. I’m the one spending the prime of my life fighting against the anti-science rhetoric being spewed by my elected officials to earn a PhD the old-fashioned way instead of just dismantling research divisions, field stations and libraries that don’t support my political platform!

Yep, he sure showed me…