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Evolution in the blink of an eye…

Prairie Deer Mouse - Peromyscus maniculatus bairdii

The cool thing about science and nature is that interesting stories are all around us. The tiny Deer Mouse, shown here, has overcome long odds, with the vast majority of its historical habitat gone. However, through some remarkable, fast-track evolutionary adaptation, they’re now able to cope with their new world. Photo by Gregory Smith.

It’s been a busy last week, without any time for birding or photography.  Or blogging, for that matter. I was down in Nebraska for a few days, mixing work and pleasure. The “pleasure” part was my fantasy baseball draft in Omaha Saturday.  Our fantasy league is likely one of the longest running leagues in the country, going back to 1985 during our freshman year in college, when fantasy baseball was still very new.  What’s great about it is that many of the original league members are still participating! It’s great fun, not only the draft itself, but catching up with old college friends.

The “work” part of my Nebraska trip was participation in the 2017 Great Plains Symposium, on the campus of the University of Nebraska-Lincoln. Much like the baseball draft, the symposium too was like stepping back in time, as I reconnected with some of my old college professors who were participating in the symposium. The focus of the symposium was “Flat Places, Deep Identities: Mapping Nebraska and the Great Plains”.  I gave a talk one some of the work I’ve been doing, mapping past, present, and potential future landscapes in the Great Plains.  It was a great symposium, a little different kind of crowd than I’m used to.  Given the work I do, most of the conferences and symposiums I attend deal with the physical sciences. This conference melded mapping, history, socioeconomics, and other social sciences that I’m not exposed to as much.  It was quite fascinating, particularly hearing about the history of Nebraska, using maps to help tell the “story” of change over time.

As part of the symposium “goodies”, participants were given a copy of The New Territory, a quarterly magazine that focuses on Missouri, Arkansas, Kansas, Nebraska, and Oklahoma.  I admit I’d never heard of the publication before. The content fits quite well with the focus of the symposium itself, with many human interest stories about the geography and people of the region. As a physical scientist, one piece caught my eye though. entitled “Evolution in the Cornbelt“, by Conor Gearin. The story focuses on the Prairie Deer Mouse (Peromyscus maniculatus bairdii), a common little fellow from the Great Plains that feeds on the tiny seeds of grasses and weeds in the prairies.

Researchers at Iowa State and Purdue University were curious how a species so adapted to life in the Great Plains has been able to thrive, given that >99% of the original tallgrass prairie in the region has been plowed under, converted to agriculture, urban land, or other man-made land uses. The grass and weed seeds the Prairie Deer Mouse had historically fed on were much more sparsely distributed than they were 200 years ago, yet the species is still quite common.  They started field work to assess the distribution of the nice, including setting up artificial nest boxes that the mice could use for habitation and food storage.  The results astounded the scientists.

Prior to beginning the work, it was assumed that deer mice populations would be the highest in “edge” habitat, areas such as grassy ditches, fencelines, or other “boundary” conditions where remnants of their traditional food sources may still be found.  However, they quickly found that the highest populations of deer mice were often right in the middle of very large corn and soybean fields, far from any traditional food source.  Clearly, Prairie Deer Mice had adapted to an agricultural setting, and were feeding on man-raised grains and pulses. The question was, how could a tiny mouse that was so well adapted to eating tiny grass and weed seeds shift gears and start feeding on corn and soybeans?

The researchers found historical deer mice in historical museums, creatures that had been preserved with taxidermy. Anatomical comparisons with Prairie Deer Mice from today found some stark differences.  The older specimens were well adapted to feeding on tiny seeds, with small mandibles and jaws that didn’t open very far.  The modern specimens had 1) significantly longer lower mandibles, 2) structural changes that allowed their mouths to open wider, and 3) larger upper mandibles. Accompanying the larger mandibles were more robust “hardware” for linking bone to muscle, with beefed up jaw muscles that enabled the tiny mice to feed on much larger food items than they had historically.

In the blink of an eye, geologically speaking, Prairie Deer Mice had shown measurable, obvious evolutionary adaptation in response to their new environment and food sources.  The researchers found high densities of deer mice in the middle of corn and soybean fields.  Some inevitably will succumb to the mechanical tools humans use to turn and manipulate the soil, but with such a rich, dense, bountiful food source, the mice had quickly evolved to fill the new ecological niche and feed on corn and soybean waste.

For a scientist like myself, I’m completely dumbfounded by the sheer ignorance of those who doubt science…who doubt climate change is real…who doubt in evolution.  The actual empirical evidence is overwhelming, conclusive, and “in-your-face”, for those who bother to open their eyes to the world around them. It’s a fascinating story, and the writer (Conor Gearin) did a great job not only summarizing the research, but telling it in a true story-teller’s fashion.  To me, this is exactly the kind of story, and writing style, that could perhaps help to turn the tide against the anti-science wave that seems to be cresting in the U.S. right now. Great story, and The New Territory really looks like a publication that’s worth subscribing to or picking up if you get a chance.

Grand River National Grasslands, Harding County, South Dakota

Expansive grasslands of the Grand River National Grasslands, in Harding County, in far northwestern South Dakota. Grassland habitat like this is greatly reduced in the Great Plains. However, that doesn’t seem to be a problem for one species, the Prairie Deer Mouse, who evidently can do quite well without an actual “prairie”.

Losing the Rainforests…and South Dakota habitat

This week the New York Times had a wonderful (as always), yet sad piece about deforestation in the Amazon rainforest. Approximately 360,000 acres in the region were deforested every year during the 1990s, a number that jumped to 660,000 acres a year during the early 2000s.  A massive push to slow deforestation rates occurred in the 2000s, temporarily slowing the rate of deforestation.  However, in the last few years the deforestation rate has skyrocketed, to over 850,000 acres every year, an area the size of Rhode Island. Every. Year.  Clearly that’s not sustainable.  Even the supposed “success” in the mid-2000s of slowing the rate of deforestation only “slowed” it, it certainly didn’t stop it or reverse the trend.  That’s the world we live in now, where SLOWING the inexorable loss of habitat is considered a major conservation success story, even if those slower rates still would have wiped out most of the rainforest during this century.

We don’t have rainforests in South Dakota.  From a birder’s perspective, we don’t have much bird habitat whatsoever in the eastern part of the state, given the preponderance of corn and soybeans that takes up the vast majority of the landscape.  Still, as a birder, I have reveled in the little reservoir pockets of remaining habitat, small micro-habitats where birds have thrived, despite the massive use of the landscape for agricultural production.  I used to bring my camera with me EVERYWHERE.  Every day when I went to work, my camera came with me.  I would stop at these little pockets of habitat, and take bird photos. Over the years, I’ve gotten some truly wonderful photographs in these small remaining pockets of habitat.

I don’t bring my camera with me to work any more. I don’t bring my camera with me when I run errands. In fact, I don’t do nearly as much birding right around Brandon and Sioux Falls as I used.  Much of the reason is that many of my former little micro-habitat “hotspots” are gone, something that’s just happened in the last several years.  There have been multiple reasons behind it.  The first is simple economics…with demand for corn and soybeans, farmers are cultivating every possible patch of land to maximize production. Fence rows, shelter belts, and other little pockets of habitat are being plowed under to expand planted acreage. There have also been active “safety” programs in the last few years to clear brush and trees from the edges of the roads.  It’s been a truly massive project, with roads all over the state undergoing this kind of “grooming”, removing habitat that is anywhere close to road edges.

We don’t have the rainforest like the Amazon, but habitat loss is having an impact right here in South Dakota.  Here are some small, and some larger, examples of what’s happening with habitat change in South Dakota, and how it’s affecting bird species. Bird photos accompanying each image are some of the actual bird photos I’ve gotten from each location over the years.

Ditch Road - Minnehaha County, South Dakota

Ditch Road, just north of Sioux Falls in Minnehaha County. There’s a stretch of road that runs over 5 miles that has a straight drainage ditch running along side it. In the last year, nearly all of the thick trees and shrubs that were found between the road and the waterway have been removed (the area encircled in red shows the vegetation that used to be there). It’s part of the aforementioned “safety” program to remove things that people could evidently crash into and get hurt.  (I always thought the point of driving was to stay ON the road). With the water and vegetation, it used to be an absolutely wonderful spot for songbirds and even some waterfowl, particularly in migration.  Warblers, Vireos, and Chickadees and Nuthatches, many woodpeckers, and other songbird species were often found here.  Not any more…

Big Sioux Recreation Area near Brandon, South Dakota

Big Sioux Recreation near Brandon, South Dakota – One that’s near and dear to my heart, given that we live on the edge of Brandon across the street from the park (house shown above). One of the best places to bird in the park used to be right amidst the campground areas themselves. The looped road shown above was lined with cedar trees, and thick brush separated many of the camping stalls from each other. The image above shows what it used to look like. The cedars in particular really attracted many birds, including one memorable winter when a hoarde of about 20 Long-eared Owls took up residence in the Campground (see photo above). In the last 2 years, all of the cedars have been removed from the campground area, as have most of the shrubs that separated camping stalls. If you want to play football? Thanks to all the vegetation clearing, it’s now MUCH more open in the campgrounds! If you really LOVE being close to other people while camping, with no pesky vegetation to get between you and the next guy, you’ll love the changes!  If you’re a bird lover? Not so much…

Minnehaha County Wetland

Minnehaha County Wetland — This one has a Google Earth image that actually catches the transformation as it happened. This is a small area in northern Minnehaha County on 253rd Street and near 481st Avenue.  Prior to 2015, the area in red was a mix of wetland, damp grasses, and weedy patches.  It was an absolutely WONDERFUL place to bird, a little patch of wet, weedy habitat that attracted species like Le Conte’s Sparrows, Swamp Sparrows, Bobolinks, Sedge Wrens, Marsh Wrens, and many other birds. In 2015, the owner installed drain tile, shown as the lines that run through the image above.  The drain tile dried out the land so it could be used for cropland, and today, this entire patch is a corn field. Drain tile installation has been RAMPANT in eastern South Dakota in the last few years. In some cases it’s been done to improve conditions on existing cropland.  In many areas though, like this, it’s being installed in areas that are naturally too poor to support crops, and need an artificial drainage system.  It’s hard to have Swamp Sparrows in an area, if you have no “swamp”.

South Dakota Shelterbelt

Shelterbelts – There aren’t a lot of woodlands and forests in eastern South Dakota, but the variety of birdlife in these little oases of trees can be truly astounding.  During migration they are definite bird “traps”, with tired songbirds stopped to rest and feed in these areas before continuing on with their migration. The photos are just examples of what you can find in these shelterbelts, as I haven’t birded this specific location before. However, it’s a great example of what’s been going on in much of South Dakota. This is north of Sioux Falls, near the intersections of Highways 121 and 122. This shelterbelt had been there the entire 23+ years we’ve lived in South Dakota, and it had some very large mature, old trees.  That changed last year, when all of the woody vegetation in the entire area circled in red was removed. This last summer it was all a big open field, planted in corn. There are many places in eastern South Dakota where this is happening, as farmers try to compensate for lowered corn and soy prices in the last few years by planting more and more acres.

Increase in Cropland Cash Rents - 2009 to 2014

What’s behind South Dakota cropland gains? — So what’s driving the agricultural change in South Dakota?  Beyond the little micro-habitat examples given above, there are some very large swaths of grassland being converted to cropland, with some much of the new cropland on land that had never been plowed before. The map above gives you some indication of the economic forces driving cropland gains in the state, and the concomitant loss of vegetated habitats.  Some of the largest recent changes in cash rent values for cropland in recent years are concentrated right in eastern South Dakota. As this article states, South Dakota had the largest increases in overall cropland value from 2004 to 2014, an increase of over 350% in just 10 years as average cropland values rose from $734 an acre to over $3,400 an acre. Prices for the major crop commodities of corn and soy have softened substantially in recent years, but that seems to have driven an intensification of land use in some parts of the state, as farmers try to maximize production by expanding the acreage that they plant.

Grassland conversion in the Great Plains

Grassland Conversion in the Great Plains – In 2013, colleagues/acquaintances published a paper the summarized the recent loss of grassland and wetland in the northern Great Plains. The map above shows the percentage of grasslands in an area that were converted to soybeans or corn between 2006 and 2011. Southern Iowa is a bit misleading, given that this shows “percentage” change, and there wasn’t nearly as much grassland there in 2006 as there was in parts of eastern South Dakota.  It really has been the eastern Dakotas where a huge chunk of cropland gains in the U.S. have occurred in recent years.  From a birder’s perspective…it hasn’t been a happy story.  Click here for the journal paper from Chris Wright and Mike Wimberly.

Losing habitat on the Plains

Grasslands - South Dakota

A gravel road and vast grasslands…one of my favorite types of areas to not only bird, but just to experience. It’s becoming a rarer and rarer sight with all the recent cropland expansion in eastern and central South Dakota.

I ran across (yet another) story this morning discussing the huge loss of habitat in the northern Great Plains over the last few years.  It’s not exactly “news” to anyone who has lives here and has paid attention.  A bit of background…in 2007, Congress passed the “Energy Independence and Security Act”.  It was a huge energy bill, with many components. One of which actually was a huge boon to my work at USGS EROS, as we became part of a huge project to look at the potential for sequestering carbon through land use practices.

However, another component is a renewable fuels standard (RFS), with hard mandates for increased use of biofuels by 2022.  In recent years the price of corn has gone up substantially, in no small part due to the RFS.  The result? Massive loss of grassland in my part of the world, with the Dakotas being hit especially hard.

It’s obvious everywhere I bird, both in eastern South Dakota (which has traditionally been a stronghold of corn production), and now increasingly in central South Dakota.  In eastern South Dakota where I live, the only remaining grasslands are 1) those that are on hilly or very rocky ground, areas too difficult to farm, or 2) individual fields that are enrolled in the Conservation Reserve Program (CRP).  CRP provides payments for farmers to keep land in a grassland cover around here, but those payments can’t compete with the profits that can be made by putting arable land into corn production.  I can point to numerous individual fields just on my drive to work that used to be CRP, and had been grassland ever since I moved here over 20 years ago, that have been plowed under and converted to cropland in just the last few years.

The further west you go in the state, the more iffy a proposition it is to grow dryland corn.  The Missouri River dividing the state into “East River” and “West River” used to be a rough dividing line on where corn was grown. Rainfall in South Dakota is a gradient from west to east, with precipitation dropping as you move westward in the state.  One of my favorite birding locations in the winter is around the Presho area. It’s an area with a lot of grasslands and a lot of pheasants (and presumably voles and mice), creatures that attract a lot of winter raptors like Rough-legged Hawks, Ferruginous Hawks, and even the occasional Gyrfalcon or Snowy Owl.  As a drier area than eastern South Dakota, cropland used to be limited to wheat, some sorghum, and sunflowers.  Not any more, as you’re starting to see farmers attempt to grow dryland corn even there.

It’s not just the conversion of complete, large fields from grassland to cropland that you’re seeing, it’s land management practices and micro-scale habitat loss.  From a land management standpoint, the other business that’s booming right now in the Dakotas is the installation of drain tile, underground piping that efficiently drains the land and allows farmers to utilize areas that once tended to collect too much water for cultivation.  One of my favorite little birding spots on my drive to work is now gone, thanks to drain tiling.  It was a low spot along a little drainage way, a moist area that had a grassland and some scattered cattails.  That area was drain tiled and is now a corn field.  From the micro-habitat side, farmers are also ripping out vegetation along fencerows and shelterbelts, trying to squeeze out every acre they can as crop prices are high.

To be frank, it’s damned depressing sometimes to drive around birding, seeing some of your favorite remaining grassland habitats being actively plowed under.  It’s a level of land-use conversion in the northern Great Plains that hasn’t been seen in many decades.

Especially as a father, I can’t help but think “when does it end”?  When do people stop thinking about MONEY, and their short-term well-being, and when do they actually start worrying about their CHILDREN’s future? It’s not just habitat loss, it’s sabotage of the very resources we need to survive.  Increased agricultural land use, drain tiling existing land, and increased fertilizer use as farmers try to bypass crop rotation and plant exclusively corn…all are pumping up nitrate and other pollutant levels in the very water supplies we depend upon to survive.

I tell myself, that just as with the inexorable spread of urban areas across the world, it can’t continue forever, right?  At some point, it has to stop, right?  The only problem is that human beings are too short-sighted to set that “limit” of when we stop degrading and destroying habitat and the resources we depend upon.  What’s going to eventually make it “stop” is ecological disaster…

Salton Sea disappearing? Good riddance…

Salton Sea - Satellite Image

Satellite image of the Salton Sea area. The patterns above and below the lake are the massive agricultural lands that have built up since diversion of the Colorado River to the area in the 1900s. The tan color everywhere else? Desert. As Mother Nature is showing us recently, there is a price to be paid for trying to maximize short-term profit and make the desert temporarily “bloom”.

Sometimes Mother Nature gives us a reminder of how much we’ve screwed up the planet.  That’s certainly happening right now in the western U.S., with an extreme drought serving to highlight human mismanagement of both water and land use in the region. While most of the focus has been on urban and agricultural water limitations, there’s also an impact on wildlife.

The Salton Sea is the largest lake in California.  It also didn’t even exist until 1905, at least not in recorded history in the West.  The Colorado River has long been an overused water source for a water-thirsty West, and in 1905 an accidental break in canals diverting water from the Colorado River resulted in two years of ALL Colorado River water flowing into the Salton Sea basin.  Since its formation, it has sporadically served as a resort destination, extremely productive fishery, and habitat for millions of migratory birds.

What’s that you say?  Habitat for millions of birds, and a bird crazy person like myself is saying “good riddance” to the Salton Sea?  Yes, without reservation.  The basin holding the Salton Sea HAS occasionally naturally filled with water over the past several thousand years, but the accident that created the current version of the Sea was anything but natural.  Before settlement of the West, the Colorado River flowed into the Gulf of California, creating a vast delta where it entered the ocean.  Once California, Nevada, and Arizona started diverting water from the Colorado, those flows to the ocean diminished, to the point that NO water from the Colorado regularly reaches the Gulf of California anymore.  A planned pulse of water was allowed to reach the Gulf in 2014, but other than that, water has only sporadically (and rarely) reached the Gulf since the 1950s.

The Colorado River’s delta has long since dried up, taking with it the natural habitat that was once found there.  Has the Salton Sea been a boon to bird life in the West?  Perhaps, although it’s hard to judge the tradeoff of creating the Salton Sea, but losing the Colorado Delta and riparian habitat associated with the Colorado River.  What everybody agrees on is that as the Salton Sea continues to shrink, there are serious health and environmental issues that are likely to occur.  The boom days of the Salton Sea are long past.  The resorts are gone, and the now extremely salty water is only able to support Tilapia, who themselves are now subject to periodic fish kills due to poor water conditions.  Diverted water from the Colorado continues to enable agriculture in the region, but as the recent drought is showing, there simply isn’t enough water to go around in the West.

“Fixing” the Salton Sea would again require diverting massive amounts of water from the Colorado River.  There simply isn’t enough of a water resource to support the Salton Sea, the Colorado Delta, and a booming human footprint in the West.   And so I say…good riddance to the Salton Sea, IF it means restoring natural flows to the Colorado Delta and Gulf of California. Yes, there will be health and environmental issues to deal with in the aftermath of the demise of the Salton Sea.  But as Mother Nature has again reminded us with the western drought, there are consequences for only thinking about short-term economic gain and human well-being, and failing to consider sustainability and long-term consequences.

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