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Re: [beemonitoring] Bombus-GroundIvy Connection?

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  • Thomas of Baltimore
    Tongue length of my locally abundant Bumble bee and frequent user of Ground Ivy: B. griseocollis possesses an intermediate tongue length (mean=6.2 mm, *n*
    Message 1 of 15 , Dec 21, 2006
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      Tongue length of my locally abundant Bumble bee and frequent user of Ground Ivy:
       
      "B. griseocollis possesses an intermediate tongue length (mean=6.2 mm,
      n=10)"

       
    • David Inouye
      That s close to the proboscis length of honey bees, which are probably significant competitors for short-tongued bumble bees in this country. At 02:42 PM
      Message 2 of 15 , Dec 21, 2006
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        That's close to the proboscis length of honey bees, which are probably significant competitors for short-tongued bumble bees in this country.

        At 02:42 PM 12/21/2006, you wrote:

        Tongue length of my locally abundant Bumble bee and frequent user of Ground Ivy:
         
        "B. griseocollis possesses an intermediate tongue length (mean=6.2 mm,
        n=10)"


         
      • David Inouye
        That s interesting that bees of all those proboscis lengths will use the same flower. Quantitative data on frequency of use by each of those species would be
        Message 3 of 15 , Dec 21, 2006
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          That's interesting that bees of all those proboscis lengths will use the same flower.  Quantitative data on frequency of use by each of those species would be interesting. Bumble bees will investigate a wide range of flowers, in my experience, but typically settle quickly on those that are a good morphological match and rewarding.

          The 5.8mm measurement for terrestris/lucorum sounds short to me.  I've seen data reporting them as about 8 mm, which then puts them in a different category from honey bees.

          At 02:13 PM 12/21/2006, you wrote:

          According to the British bumbleebee researcher I contacted, (at least) four true British Bumblebee species are known to visit Glechoma hederacea; Bombus pascuorum (most frequent), B.lucorum , B.pratorum, and B.hortorum. 
           
          Each of the four British species are listed in the "tongue length" table below.  Dr Inuoye suggested a correlation between Bombus proboscis length and use of G. hederacea.  Is that corroborated by the data I provided?
           
          Average tongue lengths mesured from foraging bumblebee workers.
          Species
          Tongue length mm
          Bombus hortorum
          12.0
          Bombus lapidarius
          6.0
          Bombus pascuorum
          7.6
          Bombus pratorum
          6.4
          Bombus terrestris/lucorum
          5.8

          (Table source: http://www.bumblebee.org/bodyTongue.htm)


          On 12/19/06, David Inouye <inouye@...> wrote:

          At 04:45 PM 12/19/2006, you wrote:

          >Background 1: In my Baltimore City neighborhood, and in many urban
          >areas, Ground Ivy (Glechoma hederacea) is now one of the most
          >important flowers for bumblebees in part because of its early season
          >bloom and because of its vast abundance and wide distribution.
          >
          >Question 1: Before Europeans arrived, while the indigenous people
          >were "managing" the landscape, what early season flower species did
          >the native bumblebee spp depend on?

          Depends on their proboscis length.

          >Background 2: (a) Wikipedia says, "In Britain, until relatively
          >recently, 19 species of native true bumblebee were recognised..."
          >(b) The Wisconsin Bumblebee regional chart lists 4 species native to Maryland.
          >
          >Question 2a: If Ground Ivy evolved in close relationship with
          >British bombus species, then the Ground Ivy we see today may be the
          >result of the selective pressure of associating with up to 19
          >bumblebee species? Wouldn't that make Ground Ivy a super bumblebee flower?

          It is unlikely that all 19 species would have foraged on a single
          plant species. The relationship between bees and plants is typically
          mediated by an appropriate match between proboscis length and corolla
          tube length, so probably only one subset of the three categories of
          proboscis length would have visited the flowers.

          >Question 2b: So now consider the possibility that our native North
          >American bombus species also prefers Glechoma hederacea because it
          >is a super bombus food. What impact on the distribution of Ground
          >Ivy would result from this preference by our native bombus
          >spp? Would an adopted preference for Ground Ivy by N.A. bombus spp
          >impact any other native/non-native early spring flowering plants
          >which may be blooming in the vicinity? And if so, in what way(s)?
          I suspect this plant is not limited by seed production and dispersal,
          so the effects of native Bombus on the introduced plant are probably
          minimal. There probably is the potential for ground ivy to have a
          negative impact on visitation to (and thereby seed set of) some
          native plants that flower at the same time.

          Dr. David W. Inouye, Director
          Graduate Program in Sustainable Development and
          Conservation Biology
          Room 1201, Biology/Psychology Building
          University of Maryland
          College Park, MD 20742-4415
          301-405-6946
          inouye@...
          FAX 301-314-9358

          For the CONS home page, go to http://www.umd.edu/CONS


        • Thomas of Baltimore
          What percentage of the world s extant flowering plant species have evolved flower arrangements that are pollinated by only a specific group of pollinating
          Message 4 of 15 , Dec 21, 2006
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            What percentage of the world's extant flowering plant species have evolved flower arrangements that are pollinated by only a specific group of pollinating insects?
             
            If specialist flower/specialist pollinator relationships are as rare as I expect, then it would seem the remaining plants have in varying degrees evolved flowers under the selective pressure of pollinators which favor it (for example, Ground Ivy & Bumblebees). But Ground Ivy and Bombus are not one of the specialist flower/specialist pollinator relationships as evidenced by the variety of U.S. insects reported to visit its blooms.  
             
            I am suggesting that over time the Glechoma hederacea flower was in part "shaped" by its long-term association with British (and European) Bombus spp.  If that is true, then the shape of the Ground Ivy flower that we see today reflects this relationship.  In a sense, we can "read" that relationship in the flower's design.  But, we also know that it is used by non-bombus species so either the design of the Ground Ivy flower leaves room for the other pollinator species, or the other pollinator species have influenced the flower design we see.
             
            Either way, it serves the Ground Ivy to maintain some pollinator access wiggle room in case the Bumblebee(s) have a bad year or worse disappear altogether.
             
            Why do I care?  Well, as Dr. Inouye suggested the introduction of a non-native flower into an ecosystem could impact other flowering plants nearby if native pollinators prefer the non-native flower over the native flower.  My line of questioning attempts to implicate the native pollinators, at least in part, to the successful naturalization of some non-native flower species.
             
            Learning more about what "role" that native species play in the spread of non-native species is important because it reframes the conversation away from the highly-charged and vague, but thoroughly unscientific terminology like "alien" and "invasive".  By asking, what if the native Bombus prefer Ground Ivy because the Ground Ivy's flower evolved to serve Bombus better, we shift away from looking for a one-sized-fits-all diagnostic that explains the how and why of each and every successful species introduction-naturalization. 
             
            In the background is an unexamined bias against "non-native" species.  If anything points to a bias against "non-native" species it is that the "non-native container" is so poorly defined and vague that anything can be placed into it or removed at will. 
             
            In this model, the non-native wheat is ok, but Ground Ivy is not. 
             
            There are many apples and oranges to be sorted out, too.  How shameful that the science community allows the Chestnut Blight, Siberian Elm, and the Starling to be lumped into a group together!   The most dangerous result of this "lumping" iwould be attempts to fashion one-size-fits-all responses to dealing with them (ie, eradication, chemicals/poisons, propaganda).   
             
            Consider this:  Not long ago, the New England population of the Baltimore Checkerspot butterfly "discovered" that Plantago lanceolata contains the same chemicals needed for its larvae to develop.  By adding the Plantain to its menu, the New England Baltimore Checkerspot's population is expanding for the first time. 
             
            In contrast the Mid-Atlantic population of Baltimore Checkerspots has not adopted Plantain so Maryland's state insect (which I've never seen in person) continues to decline in this area along with its wetland habitat.
             
            With that in mind, is wholesale and wanton eradication of the non-native P. laceolata still called for?  Or, does the emergent Baltimore Checkerspot-P. lanceolata ecological association demonstrates how far along Plantago has integrated into the environment.  (By integrate I mean the constellation of ecological associations formed between Plantago and other New England lifeforms since it arrived.)   How many micro-associations between Plantago and other species have taken place which are not as easily noticed as the Checkerspot-Plantago relationship?
             

             
            On 12/21/06, David Inouye <inouye@...> wrote:

            That's interesting that bees of all those proboscis lengths will use the same flower.  Quantitative data on frequency of use by each of those species would be interesting. Bumble bees will investigate a wide range of flowers, in my experience, but typically settle quickly on those that are a good morphological match and rewarding.

            The 5.8mm measurement for terrestris/lucorum sounds short to me.  I've seen data reporting them as about 8 mm, which then puts them in a different category from honey bees.



            At 02:13 PM 12/21/2006, you wrote:

            According to the British bumbleebee researcher I contacted, (at least) four true British Bumblebee species are known to visit Glechoma hederacea; Bombus pascuorum (most frequent), B.lucorum , B.pratorum , and B.hortorum. 
             
            Each of the four British species are listed in the "tongue length" table below.  Dr Inuoye suggested a correlation between Bombus proboscis length and use of G. hederacea.  Is that corroborated by the data I provided?
             
            Average tongue lengths mesured from foraging bumblebee workers.
            Species
            Tongue length mm
            Bombus hortorum
            12.0
             
            Bombus lapidarius
            6.0
             
            Bombus pascuorum
            7.6
             
            Bombus pratorum
            6.4
             
            Bombus terrestris/lucorum
            5.8
             

            (Table source: http://www.bumblebee.org/bodyTongue.htm)


            On 12/19/06, David Inouye <inouye@...> wrote:

            At 04:45 PM 12/19/2006, you wrote:

            >Background 1: In my Baltimore City neighborhood, and in many urban
            >areas, Ground Ivy (Glechoma hederacea) is now one of the most
            >important flowers for bumblebees in part because of its early season
            >bloom and because of its vast abundance and wide distribution.
            >
            >Question 1: Before Europeans arrived, while the indigenous people
            >were "managing" the landscape, what early season flower species did
            >the native bumblebee spp depend on?

            Depends on their proboscis length.

            >Background 2: (a) Wikipedia says, "In Britain, until relatively
            >recently, 19 species of native true bumblebee were recognised..."
            >(b) The Wisconsin Bumblebee regional chart lists 4 species native to Maryland.
            >
            >Question 2a: If Ground Ivy evolved in close relationship with
            >British bombus species, then the Ground Ivy we see today may be the
            >result of the selective pressure of associating with up to 19
            >bumblebee species? Wouldn't that make Ground Ivy a super bumblebee flower?

            It is unlikely that all 19 species would have foraged on a single
            plant species. The relationship between bees and plants is typically
            mediated by an appropriate match between proboscis length and corolla
            tube length, so probably only one subset of the three categories of
            proboscis length would have visited the flowers.

            >Question 2b: So now consider the possibility that our native North
            >American bombus species also prefers Glechoma hederacea because it
            >is a super bombus food. What impact on the distribution of Ground
            >Ivy would result from this preference by our native bombus
            >spp? Would an adopted preference for Ground Ivy by N.A. bombus spp
            >impact any other native/non-native early spring flowering plants
            >which may be blooming in the vicinity? And if so, in what way(s)?
            I suspect this plant is not limited by seed production and dispersal,
            so the effects of native Bombus on the introduced plant are probably
            minimal. There probably is the potential for ground ivy to have a
            negative impact on visitation to (and thereby seed set of) some
            native plants that flower at the same time.

            Dr. David W. Inouye, Director
            Graduate Program in Sustainable Development and
            Conservation Biology
            Room 1201, Biology/Psychology Building
            University of Maryland
            College Park, MD 20742-4415
            301-405-6946
            inouye@...
            FAX 301-314-9358

            For the CONS home page, go to http://www.umd.edu/CONS



          • Liz Day
            ... I would guess they are short of food in early spring and desperate for anything with nectar. Often in early spring I have walked around urban areas and
            Message 5 of 15 , Dec 21, 2006
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              >That's interesting that bees of all those proboscis lengths will use the
              >same flower. Quantitative data on frequency of use by each of those
              >species would be interesting. Bumble bees will investigate a wide range of
              >flowers, in my experience, but typically settle quickly on those that are
              >a good morphological match and rewarding.

              I would guess they are short of food in early spring and desperate for
              anything with nectar. Often in early spring I have walked around urban
              areas and there is very little of *anything* in bloom (at least on the
              ground; there may be bleeding sap or nectar/pollen in some trees).

              Liz Day
              Indianapolis Indiana USA
            • Liz Day
              ... This assertion confuses me. Is there not usually fairly good concensus for most organisms of concern that they either were present in N. America well
              Message 6 of 15 , Dec 21, 2006
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                >Learning more about what "role" that native species play in the spread of
                >non-native species is important because it reframes the conversation away
                >from the highly-charged and vague, but thoroughly unscientific terminology
                >like "alien" and "invasive". By asking, what if the native Bombus prefer
                >Ground Ivy because the Ground Ivy's flower evolved to serve Bombus better,
                >we shift away from looking for a one-sized-fits-all diagnostic that
                >explains the how and why of each and every successful species
                >introduction-naturalization.
                >
                >In the background is an unexamined bias against "non-native" species. If
                >anything points to a bias against "non-native" species it is that the
                >"non-native container" is so poorly defined and vague that anything can be
                >placed into it or removed at will.

                This assertion confuses me. Is there not usually fairly good concensus
                for most organisms of concern that they either were present in N. America
                well before European immigration, or else have been brought in by people
                since then? Perhaps I am not up to speed on this.

                There is a big difference between the question of whether something is
                native or exotic, and the question of whether an exotic organism's presence
                is desirable or detrimental or both or neither.

                >There are many apples and oranges to be sorted out, too. How shameful
                >that the science community allows the Chestnut Blight, Siberian Elm, and
                >the Starling to be lumped into a group together!
                > The most dangerous result of this "lumping" iwould be attempts to
                > fashion one-size-fits-all responses to dealing with them (ie,
                > eradication, chemicals/poisons, propaganda).

                >Consider this: Not long ago, the New England population of the Baltimore
                >Checkerspot butterfly "discovered" that Plantago lanceolata contains the
                >same chemicals needed for its larvae to develop. By adding the Plantain
                >to its menu, the New England Baltimore Checkerspot's population is
                >expanding for the first time.
                >
                >In contrast the Mid-Atlantic population of Baltimore Checkerspots has not
                >adopted Plantain so Maryland's state insect (which I've never seen in
                >person) continues to decline in this area along with its wetland habitat.
                >
                >With that in mind, is wholesale and wanton eradication of the non-native
                >P. laceolata still called for?

                Is it occurring?

                >Or, does the emergent Baltimore Checkerspot-P. lanceolata ecological
                >association demonstrates how far along Plantago has integrated into the
                >environment. (By integrate I mean the constellation of ecological
                >associations formed between Plantago and other New England lifeforms since
                >it arrived.) How many micro-associations between Plantago and other
                >species have taken place which are not as easily noticed as the
                >Checkerspot-Plantago relationship?

                Surely the topic of the ecological changes caused by new species
                associations as our world is flooded with non-indigenous plants and animals
                would need a whole library of studies to cover it.

                Liz Day
                Indianapolis Indiana USA
                (where bumblebees do use ground ivy)
              • Thomas of Baltimore
                Are you suggesting that Ground Ivy nectar/pollen is inferior to that which is produced by other flowers? Please share the source of your pollen/nectar
                Message 7 of 15 , Dec 21, 2006
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                  Are you suggesting that Ground Ivy nectar/pollen is inferior to that which is produced by other flowers?   Please share the source of your pollen/nectar analysis comparing Ground Ivy to other flowers?
                   
                  And, what study/data are you drawing from which demonstrates bumblebees visit Ground Ivy because they are desparate, not because they prefer it?
                   
                  On 12/21/06, Liz Day <beebuzz@...> wrote:


                  >That's interesting that bees of all those proboscis lengths will use the
                  >same flower. Quantitative data on frequency of use by each of those
                  >species would be interesting. Bumble bees will investigate a wide range of
                  >flowers, in my experience, but typically settle quickly on those that are
                  >a good morphological match and rewarding.

                  I would guess they are short of food in early spring and desperate for
                  anything with nectar. Often in early spring I have walked around urban
                  areas and there is very little of *anything* in bloom (at least on the
                  ground; there may be bleeding sap or nectar/pollen in some trees).

                  Liz Day
                  Indianapolis Indiana USA


                • Liz Day
                  ... No. ... visit Ground Ivy because they are desparate, not because they prefer it? ... there are plenty of places where bumblebee forage seems to be scarce.
                  Message 8 of 15 , Dec 21, 2006
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                    >Are you suggesting that Ground Ivy nectar/pollen is inferior to that which
                    >is produced by other flowers?

                    No.

                    >And, what study/data are you drawing from which demonstrates bumblebees
                    visit Ground Ivy because they are desparate, not because they prefer it?

                    >No data; I'm guessing. My impression from living in the Midwest is that
                    there are plenty of places where bumblebee forage seems to be scarce. I
                    sometimes wonder how they survive. But you would have to study the
                    resources in each area to get a definitive answer.

                    Liz Day
                    Indianapolis (where they seem especially scarce)
                    USA
                    > >That's interesting that bees of all those proboscis lengths will use the
                    >
                    > >same flower. Quantitative data on frequency of use by each of those
                    > >species would be interesting. Bumble bees will investigate a wide range
                    > of
                    > >flowers, in my experience, but typically settle quickly on those that
                    > are
                    > >a good morphological match and rewarding.
                    >
                    >I would guess they are short of food in early spring and desperate for
                    >anything with nectar. Often in early spring I have walked around urban
                    >areas and there is very little of *anything* in bloom (at least on the
                    >ground; there may be bleeding sap or nectar/pollen in some trees).
                    >
                    >Liz Day
                    >Indianapolis Indiana USA
                    >
                    >
                    >
                  • Mary Travaglini
                    Liz, To be certain, as someone who works in the field of invasive species, there likely will never be a way to wholesale get rid of a non-native species once
                    Message 9 of 15 , Dec 22, 2006
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                      Liz,
                       
                      To be certain, as someone who works in the field of invasive species, there likely will never be a way to wholesale get rid of a non-native species once it is well established, especially established for so long that some co-evolution has occurred, unless it was something we as humans desire to kill for food, fur, or fun, or a major disease gets it. Something like ground ivy, even if natural lands managers were able to eliminate it, will continue to love people's gardens and lawns. So part of my job is to never dream of elimating anything on a large scale, or think that way.
                       
                      In the long run, we should ultimately be concerned about the loss of habitat that harbor the native plants insects need, as well as protect those plants from new invasions by pests and pathogens. If the habitat is healthy enough, and native plant populations diverse enough, any insect that adapted to an intoduced plant ought to be able to readapt back to its original hosts if they are there or populations are restored.
                       
                      From my perspective, scientists only lump exotics together when they are addressing policy and public education issues, as we all agree there is no one single approach to any solution, and even policy issues each have a different approach when dealing with aquatic freshwater, aquatic marine, forest, wetland, grassland, soil and other pests, etc. Just like the CDC lumps diseases into bigger categories and then breaks down each one for solutions to the problem. We also don't treat all exotics as invasive, as they are not all invasive, so not every exotic is considered for control. You brought up apples and oranges--for instance, oranges are exotic in the US, but no one ever considers thinking of them as a problem in natural areas, and therefore would not get lumped with starlings for any sort of discussion, unless someone linked their country of origin, etc. I think you'll find there is not one "non-native" container definition among those of us addressing these issues and that the definitions out there are not quite so vague and poorly defined, but that perhaps public education is not getting out the way it should or that the issue is more complex than can be easily disseminated well--I agree that there could be a whole library on associations that have occurred through introductions, and the complexities of the issues. Not being an entemologist, my perspective is that insects are more likely to experience adaptations and evolutions faster than other species, and my biggest concern is that the rate of exotic exchange that has blossomed with global trade and travel, and habitat degredation and loss will ultimately be more of a detriment to insect diversity than anything.
                       
                      Mary Travaglini
                      Potomac Gorge Habitat Restoration Manager
                      The Nature Conservancy of MD/DC
                      5410 Grosvenor Lane, Suite 100
                      Bethesda, MD  20814
                      (301) 897-8570 x235
                      fax: (301) 897-0858
                       
                      "In ecological release, an organism escapes its home and parachutes into an ecosystem that has never encountered it before...a few...look around with the hopeful incredulity of juvenile delinquents who discovered the mall's security cameras are broken--and wreak havoc." Charles Mann
                      -----Original Message-----
                      From: beemonitoring@yahoogroups.com [mailto:beemonitoring@yahoogroups.com]On Behalf Of Liz Day
                      Sent: Thursday, December 21, 2006 8:06 PM
                      To: beemonitoring@yahoogroups.com
                      Subject: Re: [beemonitoring] Bombus-GroundIvy Connection?


                      >Learning more about what "role" that native species play in the spread of
                      >non-native species is important because it reframes the conversation away
                      >from the highly-charged and vague, but thoroughly unscientific terminology
                      >like "alien" and "invasive". By asking, what if the native Bombus prefer
                      >Ground Ivy because the Ground Ivy's flower evolved to serve Bombus better,
                      >we shift away from looking for a one-sized-fits- all diagnostic that
                      >explains the how and why of each and every successful species
                      >introduction- naturalization.
                      >
                      >In the background is an unexamined bias against "non-native" species. If
                      >anything points to a bias against "non-native" species it is that the
                      >"non-native container" is so poorly defined and vague that anything can be
                      >placed into it or removed at will.

                      This assertion confuses me. Is there not usually fairly good concensus
                      for most organisms of concern that they either were present in N. America
                      well before European immigration, or else have been brought in by people
                      since then? Perhaps I am not up to speed on this.

                      There is a big difference between the question of whether something is
                      native or exotic, and the question of whether an exotic organism's presence
                      is desirable or detrimental or both or neither.

                      >There are many apples and oranges to be sorted out, too. How shameful
                      >that the science community allows the Chestnut Blight, Siberian Elm, and
                      >the Starling to be lumped into a group together!
                      > The most dangerous result of this "lumping" iwould be attempts to
                      > fashion one-size-fits- all responses to dealing with them (ie,
                      > eradication, chemicals/poisons, propaganda).

                      >Consider this: Not long ago, the New England population of the Baltimore
                      >Checkerspot butterfly "discovered" that Plantago lanceolata contains the
                      >same chemicals needed for its larvae to develop. By adding the Plantain
                      >to its menu, the New England Baltimore Checkerspot' s population is
                      >expanding for the first time.
                      >
                      >In contrast the Mid-Atlantic population of Baltimore Checkerspots has not
                      >adopted Plantain so Maryland's state insect (which I've never seen in
                      >person) continues to decline in this area along with its wetland habitat.
                      >
                      >With that in mind, is wholesale and wanton eradication of the non-native
                      >P. laceolata still called for?

                      Is it occurring?

                      >Or, does the emergent Baltimore Checkerspot- P. lanceolata ecological
                      >association demonstrates how far along Plantago has integrated into the
                      >environment. (By integrate I mean the constellation of ecological
                      >associations formed between Plantago and other New England lifeforms since
                      >it arrived.) How many micro-associations between Plantago and other
                      >species have taken place which are not as easily noticed as the
                      >Checkerspot- Plantago relationship?

                      Surely the topic of the ecological changes caused by new species
                      associations as our world is flooded with non-indigenous plants and animals
                      would need a whole library of studies to cover it.

                      Liz Day
                      Indianapolis Indiana USA
                      (where bumblebees do use ground ivy)

                    • Thomas of Baltimore
                      Mary: Liz didn t post what you responded to... I, Thomas of Baltimore, did. I notice you work in the Potomac Gorge which I was surprised to read is one of the
                      Message 10 of 15 , Dec 22, 2006
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                        Mary:
                         
                        Liz didn't post what you responded to... I, Thomas of Baltimore, did. 
                         
                        I notice you work in the Potomac Gorge which I was surprised to read is one of the most biologically rich areas in the U.S. park system.  Does the Nature Conservancy think that this biodiversity sprung out of the ground?   Does the Conservancy teach that the richness of species resulted only from "natural" forces (as opposed to human intervention?)   Or, does the N.C. include the Native American people in the category of "natural" influences on the biodiversity of the gorge?
                         
                        Can you prove that some of the biodiversity in the Gorge is not a result of species introductions by the indigenous people over time? 
                         
                        The landscape that John Smith "found" along the Chesapeake Bay was a managed landscape which reflected the sum total impact of every choice made by the local (Native) people as well as the accumulation of impacts from every human activity that took place. 
                         
                        Surely, the Native Americans favored some local plants for food and medicine and discouraged others (poison ivy).  And we know that there was a network of footpaths upon which Native families and tribes traded food and furs with each other.  Then is it also not reasonable that seeds and plants also moved along these byways (both intentional and not?)
                         
                        Can you prove that non-local (non-native) plant species were not introduced (intentionally or not) to the Mid-Atlantic from New England, and vice versa?  How about from the Gulf Coast to New England (and vice versa?)  And what about between the tribes across the Appalachians from each other?  Can you prove that none of the plant species living in the Gorge were introduced (intentionally or not) by Native people's from as far away as Mexico? 
                         
                        Can you share the pollen analysis data of the Gorge soil which show what percentage of the species living there when John Smith sailed the Chesapeake were living there before humans crossed the landbridge onto N.A.?  Specifically I'd love for you to show the pollen analysis data of the period when Natives arrived in the Gorge until John Smith's sailing.  If nothing changed, then my hypothesis is wrong.
                         
                         
                         
                         
                         
                         
                        On 12/22/06, Mary Travaglini <mtravaglini@...> wrote:

                        Liz,
                         
                        To be certain, as someone who works in the field of invasive species, there likely will never be a way to wholesale get rid of a non-native species once it is well established, especially established for so long that some co-evolution has occurred, unless it was something we as humans desire to kill for food, fur, or fun, or a major disease gets it. Something like ground ivy, even if natural lands managers were able to eliminate it, will continue to love people's gardens and lawns. So part of my job is to never dream of elimating anything on a large scale, or think that way.
                         
                        In the long run, we should ultimately be concerned about the loss of habitat that harbor the native plants insects need, as well as protect those plants from new invasions by pests and pathogens. If the habitat is healthy enough, and native plant populations diverse enough, any insect that adapted to an intoduced plant ought to be able to readapt back to its original hosts if they are there or populations are restored.
                         
                        From my perspective, scientists only lump exotics together when they are addressing policy and public education issues, as we all agree there is no one single approach to any solution, and even policy issues each have a different approach when dealing with aquatic freshwater, aquatic marine, forest, wetland, grassland, soil and other pests, etc. Just like the CDC lumps diseases into bigger categories and then breaks down each one for solutions to the problem. We also don't treat all exotics as invasive, as they are not all invasive, so not every exotic is considered for control. You brought up apples and oranges--for instance, oranges are exotic in the US, but no one ever considers thinking of them as a problem in natural areas, and therefore would not get lumped with starlings for any sort of discussion, unless someone linked their country of origin, etc. I think you'll find there is not one "non-native" container definition among those of us addressing these issues and that the definitions out there are not quite so vague and poorly defined, but that perhaps public education is not getting out the way it should or that the issue is more complex than can be easily disseminated well --I agree that there could be a whole library on associations that have occurred through introductions, and the complexities of the issues. Not being an entemologist, my perspective is that insects are more likely to experience adaptations and evolutions faster than other species, and my biggest concern is that the rate of exotic exchange that has blossomed with global trade and travel, and habitat degredation and loss will ultimately be more of a detriment to insect diversity than anything.
                         
                        Mary Travaglini
                        Potomac Gorge Habitat Restoration Manager
                        The Nature Conservancy of MD/DC
                        5410 Grosvenor Lane, Suite 100
                        Bethesda, MD  20814
                        (301) 897-8570 x235
                        fax: (301) 897-0858
                         
                        "In ecological release, an organism escapes its home and parachutes into an ecosystem that has never encountered it before...a few...look around with the hopeful incredulity of juvenile delinquents who discovered the mall's security cameras are broken--and wreak havoc." Charles Mann
                        -----Original Message-----
                        From: beemonitoring@yahoogroups.com [mailto: beemonitoring@yahoogroups.com]On Behalf Of Liz Day
                        Sent: Thursday, December 21, 2006 8:06 PM
                        To: beemonitoring@yahoogroups.com
                        Subject: Re: [beemonitoring] Bombus-GroundIvy Connection?


                        >Learning more about what "role" that native species play in the spread of
                        >non-native species is important because it reframes the conversation away
                        >from the highly-charged and vague, but thoroughly unscientific terminology
                        >like "alien" and "invasive". By asking, what if the native Bombus prefer
                        >Ground Ivy because the Ground Ivy's flower evolved to serve Bombus better,
                        >we shift away from looking for a one-sized-fits-all diagnostic that
                        >explains the how and why of each and every successful species
                        >introduction-naturalization.
                        >
                        >In the background is an unexamined bias against "non-native" species. If
                        >anything points to a bias against "non-native" species it is that the
                        >"non-native container" is so poorly defined and vague that anything can be
                        >placed into it or removed at will.

                        This assertion confuses me. Is there not usually fairly good concensus
                        for most organisms of concern that they either were present in N. America
                        well before European immigration, or else have been brought in by people
                        since then? Perhaps I am not up to speed on this.

                        There is a big difference between the question of whether something is
                        native or exotic, and the question of whether an exotic organism's presence
                        is desirable or detrimental or both or neither.

                        >There are many apples and oranges to be sorted out, too. How shameful
                        >that the science community allows the Chestnut Blight, Siberian Elm, and
                        >the Starling to be lumped into a group together!
                        > The most dangerous result of this "lumping" iwould be attempts to
                        > fashion one-size-fits-all responses to dealing with them (ie,
                        > eradication, chemicals/poisons, propaganda).

                        >Consider this: Not long ago, the New England population of the Baltimore
                        >Checkerspot butterfly "discovered" that Plantago lanceolata contains the
                        >same chemicals needed for its larvae to develop. By adding the Plantain
                        >to its menu, the New England Baltimore Checkerspot's population is
                        >expanding for the first time.
                        >
                        >In contrast the Mid-Atlantic population of Baltimore Checkerspots has not
                        >adopted Plantain so Maryland's state insect (which I've never seen in
                        >person) continues to decline in this area along with its wetland habitat.
                        >
                        >With that in mind, is wholesale and wanton eradication of the non-native
                        >P. laceolata still called for?

                        Is it occurring?

                        >Or, does the emergent Baltimore Checkerspot-P. lanceolata ecological
                        >association demonstrates how far along Plantago has integrated into the
                        >environment. (By integrate I mean the constellation of ecological
                        >associations formed between Plantago and other New England lifeforms since
                        >it arrived.) How many micro-associations between Plantago and other
                        >species have taken place which are not as easily noticed as the
                        >Checkerspot-Plantago relationship?

                        Surely the topic of the ecological changes caused by new species
                        associations as our world is flooded with non-indigenous plants and animals
                        would need a whole library of studies to cover it.

                        Liz Day
                        Indianapolis Indiana USA
                        (where bumblebees do use ground ivy)


                      • Thomas of Baltimore
                        [EDIT] Can you share the pollen analysis data of the Gorge soil which show what percentage of the species living there when John Smith sailed the Chesapeake?
                        Message 11 of 15 , Dec 22, 2006
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                          [EDIT]
                           
                          Can you share the pollen analysis data of the Gorge soil which show what percentage of the species living there when John Smith sailed the Chesapeake?  And from that analysis please indicate which species were living there before humans crossed the landbridge onto N.A.? 
                           
                          Specifically I'd love to see the pollen analysis data from the period when Native peoples arrived in the Gorge until John Smith's sailing.  If nothing changed, then my hypothesis is wrong.
                        • Thomas of Baltimore
                          Mary: I am not suggesting that wholesale eradication of non-native plants will automatically result in extirpation of local bee species but I do am suggesting
                          Message 12 of 15 , Dec 28, 2006
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                            Mary:
                             
                            I am not suggesting that wholesale eradication of non-native plants will automatically result in extirpation of local bee species but I do am suggesting that in the absence of wholescale replacement of my local non-native dominated plantscape with a comparable and sustainable plantscape dominated by natives would unnecessarily compromise the stability of my local bee diversity.
                             
                            I am suggesting that the presence of the non-native plants at my local scale has served to bridge the survival of my local bee species into the present.  Knowing this does not give me the luxury to be so cavalier in my attitudes toward "non-native" species.  In fact, this has made me appreciate and respect them more!
                             
                            Do you not see the bias against non-natives that so obviously infects the quote chosen for your signature?   What kind of thinking sees a parallel between a kind of human pathology (often impoverishment) and Cirsium arvense (Canada Thistle), for example?
                             
                            -Thom
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