Fun Friday

Asian clams: the most successful aquatic invaders

Some scientist considers Asian clams (Corbicula fluminea) to be the most successful aquatic invasive species, as evidenced by their being found on every continent except for Antarctica (1, 2, 3, 4, 5, 6). In addition, the species results in the loss of a billion dollars a year in the U.S. from clogging intact pipes (7). The clams are small, typically ranging from the size of a penny to a quarter, brownish yellowish, and triangular oval. They have distinctly raised growth groves. The species may be confused with native finger clams, but native species are more oval, found buried entirely, and have very fine growth ridges (8). While multiple species of Asian clams are invading aquatic systems, the most common species is C. fluminea (9, 10).

Biology

Asian clams are filter feeders but can also feed on the substrate called pedal feeding (11). The clam has one of the highest rates of filter-feeding of any bivalve (8). Unfortunately, the high filtration rate also means that they excrete many nutrients that can cause algal blooms (12,13).

The clams are found in the bottoms of water bodies, often buried in the substrate. Consequently, they are adapted to a wide range of substrates. Clams can also survive up to 36 days without being submerged in water (11).

The clams are prone to die-offs due to silt load from spring runoff, temperatures extremes, and low dissolved oxygen, which is usually associated with low water flows (12, 14). In these conditions, the clams will die and start to decompose, releasing compounds that may be harmful to other aquatic life, like native freshwater mussels (15).

Life Cycle

Asian Clam. Photo credit Lauren Schramm

Asian clams can reproduce in large numbers as they can start reproducing at around 3 to 6 months (8). The adult lives 3 to 4 years and can produce 100,000 juveniles per year (8). Adults can self fertilize, and the fertilized eggs develop into juveniles in the gills in 4 to 5 days. (8)

Range

In the United States, Asian clams can be found throughout 44 states but have the highest numbers in the southeast, Texas, and southwest. Significant populations globally can be found in South America, Europe, and Asia. Native populations also exist in Africa and Australia.

Researchers have found that various climate change models will increase the suitable habitat for Asain clams from 6.6 percent of aquatic habitats to 12.7 percent by 2050 in the U.S. (16).

Map of significant populations of Asain Clams (solid circles), sourced from Mackie & Brinsmead, 2017.

Introduction history

It is widely theorized that they were introduced as a food source on the west coast of the United States and were first discovered in the country in 1938 in California (17, 18). Another theory is that they were hitchhikers with imported Giant Pacific oysters (Crassostrea gigas) (8). Several factors have led to successful invasions of Asian clams, including its ability to produce a high number of offspring, self-fertilization, rapid sexual maturity, lack of a parasitic life stage (most other freshwater clams have this), filter-feeding, and the ability to disperse across long distances (11). In addition, juvenile clams can travel long distances using mucus “parachutes” (8).

Management options

Unfortunately, there are limited management options as once an invader enters an aquatic system, there are several different pathways it can travel. For example, Asian clams can be disturbed via fish eating them and then being excreted in waste (19). Other dispersal methods are not fully understood but likely include; bait buckets, bilge water, live wells, water currents, and transportation by wildlife (8).

Due to the rapid spread, there have been few peer-reviewed management techniques for the clam (8). However, a physical barrier can be installed to stop the spread, the clams can be dredged for and removed, and molluscicides (a chemical that specifically kills mussels) can be used (7). The latter two options should only be limited in use as they can potentially harm native mussels.

Interactions with native mussels

Regarding interactions with other species, an emphasis should be placed on Unionidae, or the family of freshwater pearly mussels. Freshwater mussels are considered the most imperiled group of organisms in North America, with only a quarter of species having stable populations (20, 21, 22, 23, 24, 25, 26, 27).

Their declines are due to previous commercial harvesting, invasive species, sedimentation, declines in fish host species, urban development, disease, predation, poor water quality/eutrophication, dams resulting in habitat alterations, habitat destruction, and channelization (21, 28, 29, 30, 31).

Historically, native mussels dominated the streams and rivers of eastern North America (32). In addition, mussels are long-lived, with some species living up to 100 years (33). On average, many do not reproduce until age 7, which increases their susceptibility to threats contributing to their decline (34). Conversely, Asian clams typically live 3 to 4 years and reproduce early (35, 36).

Asian clams and mussels occupy the same physical space in rivers, streams, and lakes. They also are both filter feeders. It was initially thought that Asian clams did not impact native mussels (37). Although some early researchers (38) did state there were declines in native mussels due to new populations of Asian clams; these researchers were in the minority. In addition to differing habitat preferences, their ranges did not appear to overlap (39, 37, 40, 41).

Current research points to several ways Asian clams can negatively impact native mussels, including direct competition for food, displacing of juvenile mussels, and ingestion of mussel sperm. Additionally, Asian clams are prone to die-offs that produce excess ammonia, which can be fatal to native mussels (42, 43).

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Sources:

  1. Leff, L. G., Burch, J. L., & McArthur, J. V. (1990). Spatial distribution, seston removal, and potential competitive interactions of the bivalves Corbicula fluminea and Elliptio complanata, in a coastal plain stream. Freshwater Biology, 24(2), 409.
  2. Hornbach, D. J. (1992). Life history traits of a riverine population of the Asian clam Corbicula fluminea. American Midland, 248- Naturalist 257.
  3. Karatayev, A. Y., Padilla, D. K., Minchin, D., Boltovskoy, D., & Burlakova, L. E. (2007). Changes in global economies and trade: the potential spread of exotic freshwater bivalves. Biological Invasions, 9(2), 161-180.
  4. Lucy, F. E., & Graczyk, T. K. (2008). Revision of the distribution of Corbicula fluminea (Müller, 1744) in the Iberian Peninsula. Aquatic Invasions, 3, 355-358.
  5. Sousa, R., Antunes, C., & Guilhermino, L. E. D. P. S. (2008a). Ecology of the invasive Asian clam Corbicula fluminea (Müller, 1774) in aquatic ecosystems: an overview. In Annales de Limnologie-International Journal of Limnology. EDP Sciences, (Vol. 44, No. 2, pp. 85-94).
  6. Crespo, D., Dolbeth, M., Leston, S., Sousa, R., & Pardal, M. Â. (2015). Distribution of Corbicula fluminea (Müller, 1774) in the invaded range: a geographic approach with notes on species traits variability. Biological Invasions, 17(7), 2087-2101.
  7. https://www.adkwatershed.org/asian-clam
  8. https://nyis.info/invasive_species/asian-clam/
  9. Renard, E., Bachmann, V., Cariou, M. L., & Moreteau, J. C. (2000). Morphological and molecular differentiation of invasive freshwater species of the genus Corbicula (Bivalvia, Corbiculidea) suggest the presence of three taxa in French rivers. Molecular Ecology, 9(12), 2009-2016.
  10. Siripattrawan, S., Park, J. K., & Foighil, D. Ó. (2000). Two lineages of the introduced Asian freshwater clam Corbicula occur in North America. Journal of Molluscan Studies, 66(3), 423-429.
  11. McMahon, R. F. (2002). Evolutionary and physiological adaptations of aquatic invasive animals: r selection versus resistance. Canadian Journal of Fisheries and Aquatic Sciences, 59(7), 1235-1244.
  12. Phelps, H. L. (1994). The Asiatic clam (Corbicula fluminea) invasion and system-level ecological change in the Potomac River estuary near Washington, DC. Estuaries, 17(3), 614-621.
  13. Wittman, M., Reuter, J., Schladow, G., Hackley, S., Allen, B., Chandra, S., & Caires, A. (2008, December). University of California Davis, Reseach, Aquatic Invasive Species, Asian Clam pdf. (2008). Retrieved from University of California Davis: http://terc.ucdavis.edu/research/AsianClam2009.pdf
  14. Sousa, R., Nogueira, A. J., Gaspar, M. B., Antunes, C., & Guilhermino, L. (2008b). Growth and extremely high production of the non-indigenous invasive species Corbicula fluminea (Müller, 1774): possible implications for ecosystem functioning. Estuarine, Coastal and Shelf Science, 80(2), 289-295.
  15. Cherry, D. S., Scheller, J. L., Cooper, N. L., & Bidwell, J. R. (2005). Potential effects of Asian clam (Corbicula fluminea) die-offs on native freshwater mussels (Unionidae) I: water-column ammonia levels and ammonia toxicity. Journal of the North American Benthological Society, 24(2), 369-380.
  16. Gama, M., Crespo, D., Dolbeth, M., & Anastácio, P. M. (2017). Ensemble forecasting of Corbicula fluminea worldwide distribution: Projections of the impact of climate change. Aquatic Conservation: Marine and Freshwater Ecosystems, 27(3), 675-684.
  17. Sinclair, R.M. and Isom, G.B. 1963. Further Studies on the Introduced Asiatic Clam (Corbicula) in Tennessee. Tennessee Stream Pollution Control Board, Tennessee Department of Public Health. 1-75.
  18. Counts, C. L. (1981). Corbicula fluminea (Bivalvia: Corbiculidea) in. British Columbia. Nautilus, 95, 12-13.
  19. Gatlin, M. R., Shoup, D. E., & Long, J. M. (2013). Invasive zebra mussels (Driessena polymorpha) and Asian clams (Corbicula fluminea) survive gut passage of migratory fish species: implications for dispersal. Biological Invasions, 15(6), 1195-1200.
  20. Allan, J. D., & Flecker, A. S. (1993). Biodiversity conservation in running waters. BioScience, 43(1), 32-43.
  21. Bogan, A. E. (1993). Freshwater bivalve extinctions (Mollusca: Unionoida): a search for causes. American Zoologist, 33(6), 599-609.
  22. Lydeard, C., & Mayden, R. L. (1995). A diverse and endangered aquatic ecosystem of the southeast United States. Conservation Biology, 9(4), 800-805.
  23. Strayer, D. L., Downing, J. A., Haag, W. R., King, T. L., Layzer, J. B., Newton, T. J., & Nichols, J. S. (2004). Changing perspectives on pearly mussels, North America’s most imperiled animals. BioScience, 54(5), 429-439.
  24. Dudgeon, D., Arthington, A. H., Gessner, M. O., Kawabata, Z. I., Knowler, D. J., Lévêque, C., & Sullivan, C. A. (2006). Freshwater biodiversity: importance, threats, status and conservation challenges. Biological reviews, 81(2), 163-182.
  25. Bogan, A. E. (2008). Global diversity of freshwater mussels (Mollusca, Bivavle) in freshwater. Hydrobiologia, 595, 139-147.
  26. Ford, D. F. (2013). Ground-truthing Maxent in East Texas rivers. (Masters dissertation, The University of Texas at Tyler).
  27. Lopes‐Lima, M., Sousa, R., Geist, J., Aldridge, D. C., Araujo, R., Bergengren, J., & Zogaris, S. (2017). Conservation status of freshwater mussels in Europe: state of the art and future challenges. Biological Reviews, 92(1), 572-607.
  28. Williams, J. D., Warren Jr, M. L., Cummings, K. S., Harris, J. L., & Neves, R. J. (1993). Conservation status of freshwater mussels of the United States and Canada. Fisheries, 18(9), 6-22.
  29. Howells, R. G., Neck, R. W., & Murray, H. D. (1996). Freshwater mussels of Texas. University of Texas Press.
  30. Lydeard, C., Cowie, R. H., Ponder, W. F., Bogan, A. E., Bouchet, P., Clark, S. A., & Thompson, F. G. (2004). The global decline of nonmarine mollusks. BioScience, 54(4), 321-330.
  31. Allen, D. C., & Vaughn, C. C. (2010). Complex hydraulic and substrate variables limit freshwater mussel species richness and abundance. Journal of the North American Benthological Society, 29(2), 383-394.
  32. Parmalee, P. W., & Bogan, A. E. (1998). Freshwater mussels of Tennessee. University of Tennessee Press.
  33. Anthony, J. L., Kesler, D. H., Downing, W. L., & Downing, J. A. (2001). Length‐specific growth rates in freshwater mussels (Bivalvia: Unionidae): extreme longevity or generalized growth cessation?. Freshwater Biology, 46(10), 1349-1359.
  34. Kacar, A. (2011). Some microbial characteristics of mussels (Mytilus galloprovincialis) in coastal city area. Environmental Science and Pollution Research, 18(8), 1384-1389.
  35. Prezant, R. S., & Chalermwat, K. (1984). Flotation of the bivalve Corbicula fluminea as a means of dispersal. Science, 225(4669), 1491-1493.
  36. McMahon, R. F., & Bogan, A. E. (2001). Bivalves. Ecology and Classification of North American Freshwater Invertebrates. 2nd ed. Edited by Thorp, JH, and AP Covich, Academic Press, New York.
  37. Kraemer, L. R. (1979). Corbicula (Bivalvia: Sphaeriacea) vs. indigenous mussels (Bivalvia: Unionacea) in US rivers: A hard case for interspecific competition?. American Zoologist, 19(4), 1085-1096.
  38. Gardner, J. A. (1976). The invasion of the Asiatic clam (Corbicula manilensis Philippi) in the Altamaha River, Georgia. Nautilus, 90 (3), 117-125.
  39. Sickel, J. B. (1973). A new record of Corbicula manilensis (Philippi) in the southern Atlantic slope region of Georgia. Nautilus, 87 (1), 11-12.
  40. Clarke, A. H. (1988). Aspects of corbiculid-unionid sympatry in the United States. Malacology Data Net, 2(3/4), 57-99.
  41. Belanger, S. E., Farris, J. L., Cherry, D. S., & Cairns Jr, J. (1990). Validation of Corbicula fluminea  growth reductions induced by copper in artificial streams and river systems. Canadian Journal of Fisheries and Aquatic Sciences, 47(5), 904-914.
  42. Scheller, J. L. (1997). The effect of dieoffs of Asian clams (Corbicula fluminea) on native freshwater mussels (Unionidae) (Doctoral dissertation, Virginia Tech).
  43. Ilarri, M. I., Antunes, C., Guilhermino, L., & Sousa, R. (2011). Massive mortality of the Asian clam Corbicula fluminea in a highly invaded area. Biological Invasions, 13(2), 277-280.

Map source: Mackie, G. L., & Brinsmead, J. K. (2017). A risk assessment of the golden mussel, Limnoperna fortunei (Dunker, 1857) for Ontario, Canada. Management of Biological Invasions, 8(3), 383.

Asian clam ID chart: https://adkinvasives.com/Invasive-Species/Detail/31

Using Conservation Techniques to Stop Poaching of Wildlife

The following was a term paper written for my conservation biology class in collaboration with Hallie Draegert

Abstract:

It is a well-known fact that the human population is increasing in size. The growth of one population, the humans, tends to impact other populations negativity. In this case, the concern is the impact it has on wildlife populations. As long as wildlife and human populations coexist problems will arise.  These problems can occur in response to tension between local human communities and the attempts of organizations working to conserve native populations of animals. Often these organizations seem to forget that the local’s livelihoods depend on exploiting the local animals. This has led to the creation of conservation models that do not work because they did not consider the local politics.

One of the most common crimes committed is poaching. Poaching has led directly to the extinction of many species and induces stress, on currently stable species. This could make future extinction of the population an issue that needs to be addressed. Since poaching is a serious problem for highly stressed species, it is critical to work to prevent the crime. There are many current techniques used to reduce and combat poaching. However, the issue has not been fully resolved. This is likely because only a single model is in use at a time in an area.

geograph-6097299-by-Mike-Pennington
Continue reading →

Gaianism: an look at the mother earth worshipping religion

The Gaia theory was first introduced in 1979 by James Lovelock in his book Gaia a New Look at Life on Earth. The basic idea is that the earth is a self-regulating entity. While the theory was a scientific one, it launched a new pantheism religion known as Gaia worship or Gaianism, whose practitioners are known as Gaians. While Gaia worship is not new and Gaia is the oldest divine being who dates back to prehistoric times, the concepts of this religion are. For example, Gaianism is monotheistic while Gaia worshipers of the past were polytheists. Central to both the Gaia theory and the beliefs of Gaian is the concept that the earth is a self-aware being that is able to self-regulate. The relationship between the earth and Gaia is that of your body and you. The Gaians believe that this is their goddess. Many of the core concepts of this fringe pagan group stem from the Gaia theory or are directly linked to it. The three core concepts of Gaianism are honor the earth, reduce human impact on the earth, and be respectful of life in all forms and of the systems that support them.

gaia-2824197_960_720

The religion tends to be much unorganized due to the nature of pagan religions. There is a very negative cultural associated with the word pagan, therefore, many pagans prefer not to state their religion. In addition, those who have not heard of the religion obviously will not follow it. Since it is not that popular not many people have heard of Gaianism. However, the most organized group of Gaianism developed from a Wicca coven in New York City. This group called themselves Gaia Group, but was created from Coven of Caerlleuad (Castle of the Moon) in August of 1983. This group saw that other Wicca groups were changing to have more future thinking outlook rather than trying to preserve the traditions of the past. The group saw this as holding them back due to the fact the negative views of Wicca are based mostly on their past practices. The group also saw the belief systems of the past as no longer relevant. In order to make the religion more universally accepted they replaced welsh traditions and gods with an ethic focused on Gaia. The group focuses on the ideals of repairing this world and the fact that we are members of a larger community. They took part in many protests and had a strong emphasis on community service. Unfortunately, the group disbanded in 1998.

Continue reading →

Cave Ecosystems- zones and wildlife

As a cave lover, I have been on a lot of cave tours and during the tour, the cave ecosystem is always something that is discussed. They are very unique and fragile systems. The most important factor in depending on what the environment is like in the cave is what zone you are in. Caves are divided into 3 zones; the entrance, the twilight zone, and the dark zone. In the entrance, there might be green vegetation and there is a lot of light, the temperature is more variable. In the twilight zone, there is less light and minimal plant life. Finally, in the dark zone, there is no plant life and the temperature generally stays the small all year round. In most caves, it’s around 55 degrees Fahrenheit or so. All of the nutrients in this zone have to come from outside the cave.

59585_10200832048883191_1697952689_n
Lighthouse Cave in San Salvador, Bahamas, the 1st cave I ever explored

Trogloxenes and Troglobites are also important terms to know for understanding cave ecosystems. A trogloxene is a species who uses caves but they don’t spend their entire life in one. An example of this is bears or raccoons. Bats also fall into this category as they must leave caves to find insects to consume. The material brought in by trogloxenes and their poop are the only resources that troglobites have to use besides debris that may wash into a cave during a storm. In a lot of caves, bat dropping can actually serve as the major source of nutrients. Troglobites spend their entire lives in caves. A lot of caves have unique species of troglobites because they don’t leave and therefore don’t have any other populations to breed with. These species generally have really interesting cave adaptions like lack of eyes or any pigment. Pigment is lost in the cave environment frequently because it doesn’t benefit the organism and is energetically expensive to produce. Common examples of these species are cave crickets, spiders, psuedoscorpions, salamanders, crawfish and more.

Continue reading →

The Nutritional Ecology of Bird Migration

 

I attended a lecture by Dr. Susan Smith on her research related to migrating birds and berry nutrition. Migratory birds spend up to four months a year in the process of migration. These migrations are to wintering grounds and breeding grounds. During these trips, physiological demands are much greater. These trips require very large energy reserves. 79 percent of these reserves come from fats.

sort_sol_pdfnet

These stores of energy are depleted and then restored at migratory stopovers. At these sites, refueling occurs. This must be rapidly done due to time constraints (must get to wintering ground before winter). Bird’s diets change during migration to be able to rapidly refuel. Birds eat large amounts of fruit. The benefits of eating fruit in place of their normal diet are fruit is high in fat and fruit is easier to hunt. There are limits birds have to eating fruit. One type of limitations are digestive. Bird’s digestive systems can only handle a certain amount of seed load. Also, some fruits contain a certain amount of toxins and the system can handle only so much. Other limitations are nutritional.

Fruit varies in energy and protein content. Some contain up to 40 percent fat, most of these include native species. As fat content increases, energy density also increases. A hermit thrush (Catharus guttatus) (that on average weighs 31.2 grams) would have to eat 18.8 grams of bayberry (Myrica sp.) (high in fat) or 90.7 grams of pokeweed (Phytolacca decandra) to fill the daily energy needs. Eating this much pokeweed is clearly not possible.

 

hermit_thrush_283411268309229
A hermit thrush (Catharus guttatus)

 

One of Dr. Smith’s studies tried to see if birds prefer certain fruits during autumn migration time. Nets were placed around berry bushes and the amount that natural falls off was measured. The nets were removed and the amount of berries eaten during different times of the year was measured. The amount of arrowwood (Viburnum dentatum) (high in fat) eaten increased during migration, were as the amount of chokeberry (Aronia sp.) (low in fat) eaten stayed the same.

Another study was done by Dr. Smith using the plasma metabolic profile (blood samples). These samples provide information on metabolic fuel use and energetic condition. Lipid metabolites indicate how mass has changed over the last several hours (showing refueling). Other metabolites provide more information. Plasma was also sampled at two different stopover sites to compare them.

These sits were the Braddock Bay Bird Observatory and Rochester Institute of Technology Bird Observatory. At Bradock Bay Bird Observatory there was 200% more ripe fruit and this was 83% native berries (tend to be higher energy). At Rochester Institute of Technology, there were only 10% native berries. Birds were sampled the same day and same time at these locations. It was found that at Braddock Bay Bird Observatory those birds had higher triglyceride levels. This proves that fruit is helpful in birds refueling.

ringing_02_bird_in_net

Dr. Smith hopes to continue in researching the effects of fruit on birds. One study she wants to do is compare seasonal and site differences in fruits nutritional content. She also wants to look at if the bushes that provide fruit provide a year round value (such as a place to nest in or find insects). She wants to develop fruit fingers prints (light that comes off fruit when you shine a fluorescent light on it). This can be used to quickly tell if a fruit has high or low nutrients. Lastly, Dr. Smith wants to see if invasive species are so integrated into the system that removing then would cause harm to bird by removing a food source.

Vegetation Sampling: an example lab

The following is adapted from a vegetation sampling lab I did in college.

INTRODUCTION

In order to properly study an area, one has to know certain characteristics of that area. Studying the vegetation of an area has its many benefits. These include allowing us to understand the difference between communities, describe habitat, and understand how vegetation reacts to certain environmental gradients. In this lab, we focused on using the point-centered quarter method to characterize a forested slope.

From the data collected we can calculate average density per hectare, relative density, density, basal area, relative basal area, frequency, relative frequency, importance value, and relative importance value. These values allow us to compare characteristics among different species. This was the main objective of this lab.

METHODS

This study took place on Pine Hill Alfred, NY on September 9th, 2013. Following the gas pipeline trail behinds Ann’s House on the bearing N10Wo we walked 5 meters off the gas pipeline trail. At that point we placed the center of a quadrant composed of 90o quarters. Quarters 1 and 2 faced North, 1 being on the East side. Quarters 3 and 4 faced South, with 3 being on the East side. We determined the four closest trees to the quadrant, with a diameter at breast height over 10 cm. For each tree we calculated the distance from the quadrant, diameter at breast height, and the tree’s species. The same process was repeated for a quadrate located 25 meters from the path.

Continue reading →

Brief overview of Phase I environmental site assessments (ESAs)

In the field of environmental consulting conducting Phase I environmental site assessments (or ESA) is very common. This is often the 1st phase in environmental due diligence. The EPA sets the standards in which this process is carried out. The report basically outlines if there is any potential environmental contamination at a site because those who own the property are responsible for it under federal Superfund law. In response to Love Canal, in which was a massive environmental disaster in Upstate New York, the government passed the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) in 1980.  This act forced the clean up of industrial waste sites and made the owners responsible for waste on their property. COnducting an ESA ensures that property owners are protected from this liability. These reports are typically done when a commercial or industrial property purchased to ensure that the buyer is not receiving an environmental disaster that will be very costly to fix. A Phase I ESA may be required from lenders, local banks, or municipalities. They may also be required when applying for a building permit, there is a change in ownership or zoning laws are changing. Sampling of air, groundwater, and soil is not conducted during a phase I ESA. This type of sampling is included in a Phase II ESA which is done if it is evidence of environmental contamination.

gis

Continue reading →

R and K selected species

R-selected and K-selected species are terms that biologists use to describe animals’ reproductive strategies. Either an animal produces a large number of offspring, and it is a numbers game for those offspring, or the animals have few offspring and invest a significant amount of time in those offspring. R-selected species are those that favor a large number of offspring. R-selected species include insects, amphibians, many fish, and reptiles. They tend to be smaller organisms, so the energy used to make each individual is low, and they live in unstable environments. They also have shorter lifespans and reach sexual maturity quickly. They have a type III survivorship pattern which means that earlier in life, more organisms will die than later on in their life. In these species, the number of offspring is crucial because it directly impacts the population size. Continue reading →

Lupines and butterflies; a failed project and lessons learned

The summer after my 1st year of college I did a somewhat misguided ecology project related to the Karner Blue Butterfly (Plebejus melissa samuelis). The butterfly larvae only feed on wild lupines (Lupinus perennis). As lupines are early successional plants, as the Northeast transitions back into the forested lands it was before European colonization, the lupine populations are also shrinking. With those populations, the butterflies are dying out. When the butterfly was listed in 1992, 99% percent of its population was already gone. It used to be found from Minnesota to Maine, which included my home state of Vermont. Now the butterfly can only be found in Minnesota, Wisconsin, Indiana, Michigan, New York, New Hampshire, and Ohio, although reintroductions have occurred in 3 other locations. I did not do as much research about the butterfly as I should have in the planning stage of my project but we will get to that later and hopefully, this can serve as a lesson to you as well in planning future projects.

1024px-lycaeides_melissa_samuelis_28cropped29

Blue lupines (Lupinus perennis) are now endangered in the state of Vermont according to the Natural Resources Conservation Service. They have a taproot that helps to stabilize areas to prevent erosion. Since they serve as host plants and were easy to find the seeds for I bought 16,000 seeds on Amazon. I took the seeds and made them into what are called seed bombs. Seed bombs were created during the Guerrilla gardening movement, people would use them to plant flowers in empty lots that they could not otherwise access. It is basically a ball of mud, seeds, and fertilizer that you are able to throw. Here is more information on seed bombs. It is important to keep in mind what plants are native and which plants are not. I used two seeds per seed bombs because cross-pollinating lupines plants produce more seeds than those who self-pollinate. The fertilizer used was made from natural plant products, because it doesn’t raise nitrogen levels if washed in a waterway.

seed bombs
Some of my many seed bombs

The Karner Blue butterfly is only an inch wide and has very limited dispersal, an average of 1000 feet. IF I had done more research I would have figured out that planting lupines where the butterfly does not exist, literally serves no benefit to it. At the time since Vermont is in the historical range, I thought that one of the butterflies would make its way to my lupines. This project lacked practicality and enough background research. I also had no taken outbreeding depression into account when I bought random seeds on Amazon. Outbreeding depression occurs when you breed two populations that wouldn’t have breed together in the past together. The result is lower genetic diversity in the species.