Are we loving our prairies/glades/woodlands to death?

I had such high hopes for last weekend’s collecting trip – late May is boom time for insects across Missouri, we have had good moisture this spring, and I would be visiting some high-quality natural communities that I had not visited for a long time.  My stated goals (the jewel beetles, Agrilus impexus and A. frosti) were long shots – I knew that and would have been fine coming home without those species (which I did) had the the collecting been otherwise productive (which it was not).  Still, I’ve been doing this for a long time now, and I’ve learned to draw on my accumulated experience when things don’t go as planned to give myself the best shot at turning a bad collecting trip into a decent one when things don’t go as planned.  The itinerary with which I start is rarely the one that I actually follow, and this past weekend was a good example of such.

My first stop was Ha Ha Tonka State Park, one of Missouri’s premier parks, boasting high-quality chert, dolomite, and sandstone savanna interspersed with dolomite glades.  It is on these glades and savannas that I hoped to find Agrilus impexus, or failing that at least collect a nice diversity of other jewel beetles on the oaks and hickories of the savannas and surrounding woodlands.  However, it was with some reservation that I even came here after being told by my colleague at the Department of Natural Resources just 2 days before my trip that 75% of the park’s grasslands and woodlands had been burned within the past two years.  For an insect collector, this is never good news – in all my years of collecting insects, my experience in relatively recently-burned habitats has been consistent: collecting sucks!  I decided, however, to visit Ha Ha Tonka anyway because of the quality of the natural communities it contains, thinking perhaps I might be able to find pockets of unburned habitat supporting good insect populations.  This was not to be. I beat oak after oak in the savannas and woodlands – nothing!  I swept little bluestem and Indian grass in the glades – nothing!  The foliage was lush and green and the savanna and glade landscapes highly diverse – given the time of season the place should have been teeming with insect life, yet it almost seemed sterile. Were it not for a few Chrysobothris quadriimpressa jewel beetle adults that I found attracted to a recently wind-thrown black oak tree, I would not have seen any insects here at all.  It appeared my fears about park-wide depression of insect populations had been realized.  However, not one to waste a visit I decided to explore some of Ha Ha Tonka’s fascinating geological features.  Ha Ha Tonka contains one of Missouri’s best examples of karst geology, with complex structures formed from the collapse of a major cave system.  The Devil’s Promenade is one of the more spectacular examples of such, its horseshoe-shaped cliff representing the former interior walls of a now-collapsed cave.  As dusk approached, the day’s poor insect collecting caused me to abandon my plans to stay here and blacklight for nocturnal beetles.  Instead, I decided to break from the itinerary, drive further west and explore Lichen Glade Natural Area in the morning before heading to the Penn-Sylvania Prairie BioBlitz later that afternoon.

Devils Promenade, Ha Ha Tonka State Park

Lichen Glade Natural Area is a small area owned by The Nature Conservancy that boasts a high-quality sandstone glade surrounded by post oak/black jack oak forest.  My first visit to the area more than 20 years ago was during May, and it was one of the most productive collecting trips I’ve had with a number of Agrilus spp. (including A. frosti) beaten from post oak (Quercus stellata) along the woodland edge.  I didn’t visit again until fall of 2002, when Chris Brown, Rich Thoma and I found claybank tiger beetles (Cicindela limbalis) sunning on the exposed sandstone outcrops, and I made one more visit the following May to beat more insects off of post oak.  The Lichen Glade that I returned to this past weekend was a very different place from when I last visited – the surrounding woodlands had been extensively opened (I would guess within the past few years based on the size of the post oak resprouts), and fire had been used throughout the area.  Anticipation turned to frustration when no amount of beating of the woodland vegetation and sweeping of the glade vegetation turned up beetles in any appreciable numbers (or any insects for that matter) and two hours worth of effort yielded not a single buprestid beetle!

Sandstone glade community, Lichen Glade Natural Area

With resignation, I headed on over to Penn-Sylvania Prairie, where during the introduction to the BioBlitz I learned that nearly half of the 160-acre prairie was burned last December and all of it had been burned within the past few years.  I knew what I was going to find – nothing!  Okay, I shouldn’t say nothing, as there actually were some beetles present.  However, the numbers and diversity were low, with all of the species encountered representing common, widespread species.  Moreover, it was not just beetles – all of the invertebrate group leaders (which included experts on snails, ants, butterflies, and bees) reported low overall abundance and diversity in their groups of interest.  Only the vascular plants – the metric by which the value of prescribed burning is always assessed – showed high diversity, with 300 species of mostly native prairie plants recorded for the site.  It was a fun event, with probably ~75 attendees and a delicious pot luck dinner that evening; however, it would have been more enjoyable had there actually been a nice diversity of insects present to document for the preserve.

My comments may make it seem that I am against the use of prescribed burning.  This is not true - I understand the critical role that fire as a management technique plays in restoring and maintaining examples of Missouri’s historically fire-mediated landscape. Without fire and other processes to mimic natural disturbance factors, most of Missouri’s historical grasslands and woodlands suffer relentless encroachment by woody vegetation. However, the modern landscape is very different from the historical landscape, where fires of unpredictable scale, intensity, and frequency operated within a vastly larger scale to create a shifting mosaic of natural communities in various stages of ecological succession. Such processes cannot be recreated on today’s severely fragmented landscape, where the precious few remaining tracts of native habitat are relatively to extremely small and more often than not separated from each other by vast expanses of homogeneous and “inhospitable” habitat (e.g., agricultural, urbanized, or severely degraded lands).  It is in that context that I have great concerns about how aggressively fire has been used in recent years on our state’s natural areas and the impact this is having on insect populations – specialist and generalist alike.  Fire proponents will point to published studies that show little to no effect by the use of fire for managing small, isolated remnants on specialist insects (see review in Henderson 2010).  However, there are an equal number of studies that suggest such concerns are well-founded (see review in Panzer 2002). A consistent limitation in all of the studies that have been conducted is the lack of very large and long un-burned remnants.  Prescribed burning has been adopted so rapidly and pervasively that there just aren’t any significant un-burned remnants left to properly include as controls in such studies.  As a result, the insect fauna present at a given site at the start of such a study is already skewed towards those species that successfully recolonized the area post-burn.  At a minimum, the data to this point are inconclusive, and certainly the potential for impacts has not been given the consideration it warrants in designing fire-management plans for our own state’s prairies and glades. Furthermore, as rapidly and aggressively as fire has been adopted on our few, small, widely disjuct remnants, the opportunity for proper investigation of those potential effects may be gone.  A particularly egregious example of the lack of consideration being given to prairie invertebrates in designing fire management plans is shown in these photos of Iowa’s Sylvan Runkel State Preserve before and after a late May burn and the impact of that burn on a resident population of Nevada buck moths (Hemileuca nevadensis).

Here in Missouri, as in Iowa, it’s a problem of scale – the landscape is too fragmented and remnants too disjunct to manage based strictly on floristic response.   Populations of generalist insect species will recover, and even specialist species may be able to overcome such management practices if they are widely distributed and sufficiently mobile. But what about conservative species with low vagility, such as the swift tiger beetle (Cylindera celeripes) and our disjunct population of the frosted dromo tiger beetle (Dromochorus pruinina), flightless species restricted in Missouri to the few tiny remnants of loess hilltop prairie in northwestern Missouri and a single 2.5-mile stretch of roadside habitat in west-central Missouri?  Until directly relevant data, gathered here in Missouri, are forthcoming to suggest otherwise, I believe the most judicious use of fire possible should be practiced in restoring and maintaining our grasslands and woodlands.  In-season burns may have been a part of the historical landscape, but their use today has great potential to result in local extirpations and should be used only after the most careful consideration.  Leaving un-burned refugia within remnant habitats to accelerate recovery would also be prudent – yet many land managers disregard this practice because of its logistical difficulties. This is especially true in small parcels, yet it is precisely these remnants that have the most to gain from their use (or lose from not doing so!).  In the historical landscape, every burn was a patch burn – no matter what its size, there were always adjacent or proximal unburned habitat from which recolonization could occur.  Elk and bison, too, were integral components of the presettlement prairie landscape – their roamings caused intermittent, localized disturbances that were likely not only crucial to the tiger beetles that I study but may also have contributed to vegetational diversity through patch succession.  Techniques that mimic these natural disturbance factors include mowing, haying, and managed grazing.  They can be utilized to mimic those disturbances as well as delay woody encroachment, and their use in land management should be considered for their ecological value rather than deprioritized because of their relatively greater complexity and cost to implement. Mechanical removal and selective use of herbicides offer additional tools for addressing woody encroachment while minimizing potential impacts to insect populations. An effective management program that considers all of the flora and fauna of a remnant may not be possible unless all of these management tools are utilized, or at least properly considered. As my good friend James Trager said in a recent email (quoting Andrew Williams), habitat restoration “cannot rest on any single management practice, nor practicing it too extensively.”

REFERENCES:

Henderson, R. A.  2010. Influence of Patch Size, Isolation, and Fire History on Hopper (Homoptera: Auchenorrhyncha) Communities of Eight Wisconsin Prairie Remnants.  Wisconsin Department of Natural Resources, Research Report 189, 22 pp.

Panzer, R. 2002. Compatibility of prescribed burning with the conservation of insects in small, isolated prairie reserves. Conservation Biology, 16(5):1296-1307.

Copyright © Ted C. MacRae 2010

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About Ted C. MacRae

Ted C. MacRae is a research entomologist by vocation and beetle taxonomist by avocation. Areas of expertise in the latter include worldwide jewel beetles (Buprestidae) and North American longhorned beetles (Cerambycidae). More recent work has focused on North American tiger beetles (Cicindelidae) and their distribution, ecology, and conservation.
This entry was posted in Buprestidae, Cicindelidae, Coleoptera, Lepidoptera, Saturniidae and tagged , , , , , , , , , , . Bookmark the permalink.

23 Responses to Are we loving our prairies/glades/woodlands to death?

  1. Heath says:

    Sorry your collecting trip didn’t live up to expectations. I have only had one experience collecting in recently burned areas it was in southern Colorado and was equally depressing. I think that your point about the effect of fragmentation is especially important to consider when it comes to the relationship between burning and invertebrates. A huge number of herbaceous plants come back by sprouting from underground structures or through the seed bank in the soil. These simply aren’t options for most insects. I look forward to reading the papers that you referenced.

    • I had a snarky line in an earlier draft of this post that dealing with that point – something about insects exposed to burning never recover. You made the point much more elegantly.

  2. I agree, Ted. I see the same thing occurring in Southern Ohio. Burning has become the number one tool for managing Xeric Limestone Prairies, but there is no historic evidence that fire was ever a factor in sustaining this type of community. It is more likely that shallow soils and super dry conditions kept out encroaching woody species.

    It’s not only arthropod populations that are suffering. There are many plants endemic to these dry barrens that are not tolerant of fire. Spring burns can eliminate the entire year’s population of winter annuals such as Leavenworthia or some of the rare Drabas.

    In the early 1990’s I was helping write a standard for management of barrens and glades in Ohio. Many of our sites are less than an acre in size, widely scattered and separated by woodland. I proposed that burns be restricted to no more than 1/3 of the site per year so that plants and insects would be able to recolonize the burned portion. I felt it was unlikely that any organisms would move through the woodlands to recolonize remote sites. Burn managers felt that was an unmanageable alternative and currently burn the entire site as well as a good portion of the surrounding woodland. For many plants, this type of management really adds vigor to the population. I’m afraid that no one is monitoring closely enough to see what we might be losing.

    Sorry your trip wasn’t as you had hoped.

    • Thanks for chiming in, Steve. You strike me as a land manager who considers all of the biotic elements on your site and not just the plants.

      The refusal by land managers to utilize patch burning and leave refugia is the most maddening aspect for me. Yes, complete burns are much easier to manage, but if you wipe out ultra-conservative species by doing this, then what, in the end, have you accomplished? I am utterly incensed by those Sylvan Runkel State Preserve photos – mortality of the buck moths at that site is likely near 100%.

      Interesting point about the lack of evidence for fire as a factor in sustaining xeric limestone prairies (and I can’t tell you how impressed I am with your use of that term rather than following my much more common but incorrect use of the term “glade”). We do see rapid vegetational encroachment by redcedar on our examples of this habitat throughout the Ozarks, so it’s hard for me to imagine how this was prevented historically unless by fire. Perhaps our sad history of overgrazing these sites is a contributing factor, and maybe it is the vastly greater population of redcedar that is now present and the increased seed bank it produces that is causing such rapid invasion in modern times.

      • Katie says:

        I’ve been enjoying your blogs and comments, Ted and Steve. You’ve both provided me much food for thought. A Yosemite ranger told me they now focus on managing their resource by “cultural restoration”, because native Americans here in CA burned regularly and today’s international visitors expect to see this altered state as being “natural”. I’m extremely curious to know what you think the goals should be for restoration management. Are you hoping for pre-European and pre-human impact? Just wondering.
        http://www.californiachaparral.com/enativeamericans.html

        • Hi Katie – You bring up an interesting question, and one that I’ve struggled with myself. There is still some debate here about the contribution that Native Americans made in creating certain habitats within the state – e.g., the sand prairies in southeastern Missouri, loess hilltop prairie in northwestern Missouri, and open woodlands historically seen throughout the Ozarks. The problem in trying to distinguish between the impacts of Native Americans and what the landscape would have looked like had they not been here is that the climate has also changed much in the time since their arrival ~12,000 years ago. There have been cooling periods and warming/drying periods during that time that were much more extreme than anything we’ve seen in post-Columbian times. These climate swings must have had impacts on natural communities far greater than anything the Native Americans have done. I tend to believe that the sand prairies and loess hilltop prairies are xeric enough to have maintained themselves as such without human assistance, and that it is the suppression of fires during the recent past combined with heavy grazing by cattle that has led to their shrinkage. Likewise, it’s hard for me to imagine that the historically open woodlands that occurred so pervasively throughout the Ozark Highlands depended entirely upon Native Americans for their maintenance. I guess my preference is for modern managers to try to create/maintain habitats that are representative of what could be expected in the absence of human intervention and in with today’s climate (assuming an intact landscape).

          More specific to the link you provided, I think they make essentially the same argument. However, the coastal shrub communities of California are very different from the coniferous woodlands of the Sierra Nevada – certainly the ecology of the latter is naturally adapted to lightning-induced fires because they are so common. Regardless of the kind of burning that was done by Native Americans in Yosemite and the rest of the Sierra Nevada, it seems clear to me that fire is essential part of that ecosystem.

        • The decision of what model to use for restoration efforts has probably been debated as much as what methods to use. I usually aim for the rarest naturally occurring ecosystem that the site can support. Your target should be something that is practical and achievable. For example, trying for a pre-settlement forest in Southern Ohio would not be considered practical because we have managed to exterminate the American Chestnut, which was a dominant species of that time.

      • In Southern Ohio, it’s thought that prior to European settlement Xeric Limestone Prairies were more rare than they are today. Most of this area was historically mature deciduous forest and open areas would have been severely limited. XLP’s were most likely limited to the tops of rocky bluffs and promontories, rocky ridge tops and temporary openings in the forest. Some evidence suggests that bison wallows also played a part in providing suitable open conditions for these plants.

        We have several areas where a few inches of soil atop a rocky bluff support an extensive population of barrens endemics. Many of these sites are squeezed in between the woods and the cliff and are so small they are measured in square feet instead of acres. These have most likely been persistent sites for thousands of years and served as a seed source when new areas became open to colonization. We also have areas of unstable soils that tend to slip when subjected to the increasing weight of growing trees. These slip areas usually develop in succession, and as new areas of bare soil develop, barrens plants from the previous slips move in. These are the methods thought to be responsible for the persistence of prairie type vegetation in this area.

        In the early 1800’s, almost all of the standing forest of the area was cut and made into charcoal for the growing iron smelting industry. In the middle to late 1800’s, extensive amounts of this cleared ground were plowed for crop production. This resulted in severe erosion and the soils were soon degraded to the point where they could no longer support the growth of crops. Grass was planted and improper grazing techniques led to further degradation of the soil. In the early 1900’s, large amounts of this land were abandoned. These dry, inhospitable sites were perfect for colonization by plants growing in the XLP’s.

        As these newly developed prairies grew, they improved soil conditions to the point where woody species could invade. One of the first to colonize these areas was Eastern Red Cedar, a species that had probably maintained its population by colonizing naturally occurring openings in the forest. Cedar is soon crowded out by resurgence of the deciduous forest, so it was probably much less common during pre-settlement days.

        So, it appears that on many of our sites, we are managing XLP’s of more recent creation and the conditions are conducive to a more rapid encroachment by woody species. Probably the historic populations suffered the same fate and only survived through the continued colonization of new sites.

        If we controlled enough land, we could aim to recreate these nomadic populations that followed newly created openings. Many of the plants of the XLP’s do not thrive in a stable environment and require disturbance of the soil in order to maintain their populations. They were probably the first to jump into newly created openings, but are now forced to keep going on sites that are becoming increasingly stable.

        • Fascinating! I don’t know nearly as much about the origin of our glade complexes, but I think they are less ephemeral than yours. We have two main complexes – Jefferson City just south of St. Louis, and a much larger one in the White River Hills of extreme southwestern Missouri. Both of these are dolomite bedrock on south and west facing slopes or on the tops of hills (“knobs”). There are other smaller glade complexes scattered throughout the Ozark Highlands on dolimite, limestone, sandstone, and rhyolite substrates.

          The nomadic nature of your XLPs reminds me a lot of many of our tiger beetle species, which colonize open ground created by disturbances that often last only a few years before succession fills them with vegetation and makes them unavailable for the tiger beetles. This is especially true of the big river sand associates, who likely moved up and down the river systems colonizing new sand deposits from flooding before they became colonized by willow and cottonwood.

  3. Modoc Charlie says:

    Hi Ted:

    Your photo of the Devil’s Promenade at the one state park brings back fond memories for me of my
    cave exploring days as a high school boy in Nashville, Tennessee. Made lots of trips out of Nashville
    to the great limestone caving country of middle Tennessee in those days. Unfortunately it was before
    I did much with a camera, so only have a few very old slides, and those are starting to fade.

    I also didn’t do any insect collecting in those days either, wish I had.

    Charlie S.

    • Hi Charlie,

      Didn’t know you grew up in this area – yep, MO/KY/TN is the place to be for caves. These collapsed ones are just as fascinating as the existing ones. Devil’s Promenade is the largest collapsed one I’ve ever seen (at least that I recognized as such).

  4. Michael D. Warriner says:

    What a great post! When I worked at the Arkansas Natural Heritage Commission this was a bone of contention for a few of us who thought that prairie natural areas should have unburned refugia. Percevied logistical problems (just get it done, quick and dirty) with maintaining unburned sites always won out. What always bothered me about the use of fire on Arkansas natural areas was that there was no effort put into quantitative assessment of how fire was actually impacting the natural community. It was just assumed that if it was grassland or glade it needed fire and often, regardless of what impact it might actually be having. Reliance upon single season fire (spring burns only) was also a problem, so much so that certain grasslands there have lost their forb diversity and are pretty much grass-dominated.

    • Hi Michael, and thanks! I must admit I’m waiting for the other shoe to drop – there are probably some people in our state that will not like this post, so each new comment I begin reading with a bit of trepidation. I’ve bitten my tongue for long enough on this issue, and seeing those Hemileuca photos on the heels of last weekend was the last straw…

  5. Justin Thomas says:

    As a Missouri botanist and a proponent of prescribed fire I am glad you are speaking out on this issue. I share your concerns. As you mentioned, the extreme fragmentation and altered spatial dynamics of eastern North America’s historical natural communities, inevitably lend an element of artificiality to any attempts at management. Unfortunately, we have little to no way of knowing if the presence of conservative invertebrate species is itself the result of decades of fire suppression. In other words, could the current assemblage of conservative invertebrate species in these communities, that are known to be fire adapted, actually be an artifact of so much fire suppression? Were there also conservative fire adapted invertebrates that have since been displaced due to fire suppression?

    It seems that plants have been used as a gauge of the past structural and composition diversity of natural communities because they yield more slowly to changes in biotic and abiotic factors than do animals (including insects) which can exhibit more of a “flash in the pan” dynamic due to shorter lifespans, immigration and emigration; I’m thinking trees, long lived perennial forbs and seed banks.

    I don’t know the answer to these questions but it seems obvious that the scientifically responsible thing to do is to conduct extensive monitoring (pre-burn and post-burn) of all major plant and animal groups before something as irreversible as 100% black fires are conducted. Government agencies should be held accountable to the public trust by demonstrating cautious management with solid numbers not the anecdotal recollections of their staff. No such system is currently in place for the vast majority of burn programs, which are taking on a strange cultural phenomenon all their own. This is especially disconcerting in terms of the recent craze for “growing season” burns which themselves appear to have no historical antecedent. Bottom line, we need data!

    • Hi Justin – thanks so much for your comments. You bring up an excellent point regarding the possibility that the presence of conservative species in fire-suppressed systems might itself be an artifact. I’ve thought about that and don’t know that I have an answer.

      In the insect groups I am familiar with, most of the “unusual” species associated with Missouri’s glades seem to be eastern outposts of Great Plains species – are these remnants of historical populations that were distributed more broadly when fire was more common, or are they more recent expansions into previously uncolonized areas made possible by wide-scale fire suppression? I can’t claim to know the answer, but logic tells me it is the former.

      Part of me wonders if the commonly used 3-4 year return cycles are just too frequent for insects. Just because such short intervals result in maximal floral diversity does not mean that it is optimal for insect populations (at least in the context of our current fractured landscape). I suspect that historical fires in Missouri were not nearly so regular, with return intervals on a given site ranging from 0 to 50 years or more! Regularity of burn is not something I’ve seen addressed in great detail, but I think it could have been an important factor in the historical landscape.

      In the end, however, you’re right – there is a public trust issue at hand here. There seems much more enthusiasm for conducting burns then there is for gathering the data needed to support that it is the right thing to do.

  6. I can really understand your frustration with burning. Back in IL I collected dozens of sites that prescribed annual burning of roughly 25% of the prairie. The intent was to burn a little every year to equal one big fire every four years. They probably did this mostly for the press. In practice 50% or more would end up getting burned depending on how poorly it was managed. The results were horrible, insect diversity was amazingly low every year I collected – but a few showy butterflies did really well with this practice. I think the Karner Blue Butterfly is one that loves the fire – so all else falls to the wayside. The Field Museum did a study of pre and post burns in a chicagoland prairie around 2004. I believe species diversity never recovered over the course of the 4 year study (wish it had run longer though…)

    While tall-grass prairies could probably use a good burn every decade, the practice seems to be out of control in a few places. Mowing, grazing and hand-pulling should be used a lot more frequently! How did burning get so popular!?

    • I know my experiences are purely anecdotal and carry little weight in the face of published studies by recognized ecologists that say burning has no long-term impact on insects (e.g. Henderson 2010). However, the trend is too consistent to deny – whenever I try to collect insects in an area that burned anytime within the past few years, I do not see insects. I’m not just talking about my chosen specialty groups, I’m talking about insects overall. In Oklahoma last year I collected at Four Canyon Preserve – most of it burned the previous year (wildfire), and the only place on the preserve that I found good collecting were in the refugia. On the way back I stopped off at Tallgrass Prairie Preserve (managed extensively by burning), but the collecting was so terrible that I gave up after just a couple hours and moved on. In Missouri during the 1980s, two of my favorite collecting sites were Victoria and Valley View Glades – I collected at one or both spots almost every week for most of that decade. The began burning those sites in the early 1990s, and although floristically they appear much improved, I have not had any luck collecting insects there – I’m not just talking a 25-50% reduction in numbers and diversity, but a 99.9% reduction! I can’t even collect the common species I used to encounter there anymore, much less the rarities.

      Burning is popular because it is cheap, easy, fun, and dramatic!

  7. Michael D. Warriner says:

    In the case of Arkansas, where prescribed burning of natural area grasslands is the rule, it is actually quite hard to find contractors to do things like haying. The natural areas program there is very small (only three full-time stewards for over 60 natural areas) and has no heavy equipment (no tractors, no brush-cutters) of its own. While the agency burn crew can do small burns (50 acres) they contract with the state TNC chapter to do larger burns. It was quite problematic when they did try to contract with someone to hay prairies – had to get it through state budgeting rules. Even then there were only two individuals willing to do it and that pretty much fizzled after a couple of years. Grazing is impossible as fences don’t exist on most areas and would have to be installed. Probably couldn’t get permission through state procurement anyway. In the end, burning is simply the easiest thing to do.

    • Frustrating. Your experience certainly shows why other techniques aren’t utilized (although that doesn’t make it right), and I’d even be okay with burning as the only management tool used if more attention were given to refugia and longer fire return intervals.

  8. Lon Crosby says:

    Interesting blog & comments. However, I can’t figure out what people want. Maximum biodiversity for the current or a future (or a past) time period? Actual biodiversity for a specific point in time – pre-Columbus, pre-European settlement, 2000 years ago, the end of the 1000 year drought, 12,000 years ago? And for which family/genus/species? No one talks about biodiversity of Archaea, even though they probably have a significant impact on the biological “health” of everything above them – including us.

    Climate change has been a cyclical process for at least 3 million years. Human activity may speed the process up but humans have no fundamental impact. Changes over the past 12k years are mind boggling – and mostly have nothing to do with human activities.

    The impact of grazing on biological diversity is probably over-estimated except for those interested in the ecological impact of the depopulation of North America (95 to 98%) that occurred from diseases introduced by early explorers. The historical record suggests that De Soto never saw a buffalo in a 3 year trek that went North from Florida to Lake Michigan and down to Texas. The prairie observed by early European explorers appears to be the result of an ecological disaster.

    • Hi Lon,

      An interesting perspective. Most people I know advocate for restoring habitats to their pre-European settlement state, with the goal to conserve as much of the biodiversity those habitats contained as possible – plants, vertebrates, invertebrates, etc. Few people may talk about Archaea, but that does not mean they don’t advocate their conservation as well – it is the functioning system that is the goal, not selected taxa.

      Your assertion that humans have no impact on climate is a matter of debate, but what is its relevance to this discussion? Can you also explain what is this “ecological disaster” that you refer to regarding the prairie?

  9. James C. Trager says:

    Lon — You make some interesting points, but I think are missing the point. We want to protect viable populations in viable habitats of all species now sharing the planet with us, limited only by “natural” extnctions through forces beyond our influence. And we desparately want to learn how best to do so!

    I would be interested to read if you could further elaborate on the ecological disaster that created the praire

  10. Pingback: Carny of the Spineless rolls in (on a trail of slime) « hectocotyli

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