Southeastern Naturalist
M.P. Brannon, J.K.H. Brannon, and R.C. Baird
2017
4
Vol. 16 Special Issue 10
Educational Applications of Small-Mammal Skeletal
Remains Found in Discarded Bottles
M. Patrick Brannon1,*, Janis K.H. Brannon2, and Richard E. Baird3
Abstract - Environmental literacy is becoming an increasingly important part of national
and state curriculum standards. Scientists can assist teachers by providing citizen-science
research opportunities and other educational outreach programs for local students. Middle
school students from Summit Charter School in Cashiers, Jackson County, NC, in conjunction
with a roadside litter cleanup community-service project, assisted researchers from the
Highlands Biological Station who were examining discarded bottles as a source of smallmammal
mortality. Students sorted and weighed recyclable materials and inspected open
bottles for small-mammal remains. They collected approximately 141 kg of trash along 2
roads near their school, 59.4% of which was recyclable material consisting primarily of
glass and plastic bottles. Students removed 8 specimens from 5 bottles, including 6 Blarina
brevicauda (Northern Short-tailed Shrew), 1 Sorex cinereus (Masked Shrew), and 1
S. fumeus (Smoky Shrew). Students learned to distinguish small-mammal skulls based on
dentition and other cranial characteristics while using dichotomous keys, and reconstructed
skeletons using anatomical diagrams traditionally used for owl-pellet dissections. Educational
programs that incorporate immersive, hands-on, real-world experiences, especially
those that use the local community as a framework, can enhance students’ appreciation for
the natural world and provide the knowledge and skills they will require to make informed
environmental decisions as future community leaders.
Introduction
Informal science education, such as programs provided by biological fieldstations
and nature centers, extends student learning beyond the classroom through
immersive, outdoor, hands-on activities that allow students to discover and practice
science, technology, engineering, and math (STEM) concepts (NGA 2012). The use
of the outdoors as a learning laboratory provides students with direct experiences
in the natural world (Leopold Education Project 2016). Environment-based education
can also significantly improve critical-thinking skills and strengthen students’
connections to the community (Ernst and Monroe 2004). Environmental education
is not only a key component of science literacy and citizenship education, but also
STEM-career development (Sobel 2005).
It is widely recognized that current K–12 education should incorporate methodlogy
and curriculum to prepare students to become environmental leaders. The
ability to solve complex 21st-century problems will require a scientifically literate
1Highlands Biological Station, 265 North 6th Street, Highlands, NC 28741. 2Summit Charter
School, 370 Mitten Lane, Cashiers, NC 28717. 3Department of Biochemistry, Molecular
Biology, Entomology, and Plant Pathology, Mississippi State University, Box 9655, Mississippi
State, MS 39762. *Corresponding author - pbrannon@email.wcu.edu.
Manuscript Editor: Karen Powers
The Outdoor Classroom
2017 Southeastern Naturalist 16(Special Issue 10):4–10
Southeastern Naturalist
5
M.P. Brannon, J.K.H. Brannon, and R.C. Baird
2017 Vol. 16, Special Issue 10
society (Feinstein et al. 2013). National science-education standards utilize inquirybased
learning interwoven with environmental literacy (Leopold Education Project
2016) to increase students’ capacity for abstract, conceptual thinking applicable to
real-world scientific issues (Komoroske et al. 2015). Community partners can assist
teachers in the effort to guide and encourage student learning (Falco 2004). In addition
to conducting primary research, scientists are particularly well-suited to engage
in STEM educational outreach because scientific research is inherently an inquirybased
process (Komoroske et al. 2015). Scientists can share their knowledge and
expertise in environmental issues and assist students with research projects or other
hands-on, community-based programs and activities with curriculum standards as
the foundation (Ernst and Monroe 2004, Falco 2004).
Citizen-science inquiries, especially those that apply scientific methodologies
in a field setting, inspire, educate, and can produce useful and meaningful data
(Bonney et al. 2009, Prisby and Super 2007). Projects based on the identification
and investigation of problems by residents, with “action research” as the dominant
methodology, are fundamental to the interests of all citizens (Hart 1997). The ability
to understand complex human and ecological interactions can help students
meet national and state academic standards while providing the knowledge and
citizenship skills they will need to make informed environmental decisions (Archie
2004, Wyner et al. 2014).
Many schools, such as Summit Charter School in Cashiers, Jackson County,
NC, have adopted “place-based” education, which incorporates the environment
into their regular curriculum using explorations of local issues, community service
projects, outdoor learning experiences, and themes that integrate multiple disciplines
with examples from the immediate region (Archie 2004, Sobel 2005). In
conjunction with an Earth Day community-service project to remove trash along
roads, middle school students volunteered to assist scientists from the Highlands
Biological Station (HBS) who were examining litter as a source of mortality for
small mammals. Bottles discarded along roads can frequently serve as lethal traps
for wildlife (Arrizabalaga et al. 2016, Benedict and Billeter 2004, Brannon and
Bargelt 2013, Hamed and Laughlin 2015, Kolenda et al. 2015). Small mammals
may enter bottles during exploratory activities and are often unable to escape
because of the steep angle of incline, slippery interior surface, and narrow neck
(Morris and Harper 1965); they may drown if the bottle contains rainwater (Clegg
1966). This phenomenon has been found to be widespread and affect numerous
species in this region, particularly shrews (Brannon et al. 2010). Remains found
in discarded bottles can have various educational applications, such as providing a
source of small-mammal distributional and taxonomic data (Brannon et al. 2010,
Pagels and French 1987).
Field-based citizen-scientist projects like this can also help to raise student
awareness of environmental issues such as the biological effects of littering and
other anthropogenic activities (Kolenda et al. 2015). High concentrations of
discarded bottles can reduce the local abundance of individual species of small
mammals and may be a conservation threat to those that are uncommon or rare
Southeastern Naturalist
M.P. Brannon, J.K.H. Brannon, and R.C. Baird
2017
6
Vol. 16 Special Issue 10
(Hamed and Laughlin 2015, Laerm et al. 2000). Here, we present the results from
a school outreach program in which students inspected bottles discarded near their
campus for skeletal remains of small mammals. Educational goals of this project
were designed to connect to science curriculum standards, including to: (1) learn
about “the 3 Rs” (reduce, reuse, recycle); (2) understand the impacts of littering
on wildlife; (3) practice using dichotomous keys to identify species by their skulls
and other skeletal anatomy; (4) practice using GPS to map species distributions
and examine regional small-mammal biogeography; (5) better understand experimental
design and the scientific method, including practical field techniques and
proper collection and application of data; and (6) learn about STEM careers from
a local biologist.
Methods
On 21 April 2008, 3 teachers and 44 science students from grades 6–8 at Summit
Charter School performed a “litter sweep” at 2 forested, vehicle pull-off areas along
primary roads in Cashiers, NC, where copious amounts of bottles and other trash
tend to accumulate (Brannon and Bargelt 2013). We selected sites based on their
proximity to the school, and safety for the students, including thickness of the vegetation
and steepness of the slope. The first collection site (site #1) was located 1.8
km south of Silver Run Falls on Hwy 107 (35.054N, 83.064W; elevation 1028 m).
The second collection site (site #2) was located on Hwy 64 at the junction of Norton
Road (35.109N, 83.148W; elevation 1155 m).
Participants wore blaze-orange vests and leather work gloves for safety while
collecting litter. At each site, students walked ~400 m of road length and removed
any trash they could lift. Students collected litter on the road shoulders and down
embankments up to 25 m into the vegetation. We defined bottles as plastic or glass
containers of any size, but collected primarily soda and beer bottles. Students located
bottles visually and by shuffling their feet to uncover those buried in leaves
(Brannon et al. 2010). Students identified the presence of small-mammal remains
by evidence of dried fur, foul odors, murky water, and dead invertebrates such as
carrion beetles (Gerard and Feldhamer 1990), and placed these bottles into individual
re-sealable 4.4-L (1-gal) plastic storage bags to avoid spilling and losing
contents. Although we also examined the contents of aluminum cans, we never
found any skeletal remains. Participants placed all litter into 185-L (42-gal) plastic
garbage bags and labeled each with collection locality.
At the school, students weighed the bags of litter from each collection site, after
which they sorted contents into recyclable and non-recyclable materials (Jackson
County, NC, Solid Waste and Recycling Department, Sylva, NC, pers. comm.). The
students weighed all recyclables together, then further sorted them by material type.
Students sorted bottles by the presence of caps, and classified those without caps as
potential traps for small mammals (Brannon and Bargelt 2013).
Unlike skeletal remains contained in most commercially available owl pellets,
those removed from discarded bottles have not been sterilized. Therefore, the students
wore latex gloves and paper dust masks during their inspections. Students
Southeastern Naturalist
7
M.P. Brannon, J.K.H. Brannon, and R.C. Baird
2017 Vol. 16, Special Issue 10
carefully extracted and teased apart contents with forceps to find bones (Brannon et
al. 2010). We gently rinsed skulls, mandibles, and other bones, and placed them into
labeled bags for each site for later deposition at the HBS. Students used dichotomous
keys, based primarily on dentition (Key 1996), to sort skulls by regional small-mammal
taxonomic group (Johnston 1967). They identified to species all shrew skulls
by number and arrangement of the unicuspid teeth and by other distinctive cranial
characteristics (Caldwell and Bryan 1982). Three skulls were broken or missing their
teeth, but students made identifications through comparisons to HBS reference collections.
We calculated entrapment frequencies for each species as the number of
specimens collected divided by the total number of open bottles. We also plotted distributions
of individual species on maps using GPS coordinates obtained at each site
(Brannon et al. 2010). For further educational benefit, students partially reconstructed
each small-mammal skeleton using bone-sorting charts and anatomical diagrams
traditionally used during owl-pellet dissections (Key 1996).
Results
Students removed a total of ~141 kg (320 lb) of litter, of which 84 kg (59.6%)
were recyclable materials consisting of 1.6% aluminum cans, 7.1% cardboard
boxes, 40.0% glass bottles, and 10.7% plastic bottles, by weight. We collected a
total of 71 bottles—56 glass and 15 plastic. Of these, 39 (54.9%) lacked caps, with
an average of 19.5 open bottles (traps) per site. We found small-mammal skeletal
remains at both sites and in 5 (12.8%) of the open bottles.
Students identified the bones of 7 shrews in 4 different bottles from site #1.
They extracted a total of 6 Blarina brevicauda (Say) (Northern Short-tailed Shrew)
from 2 glass and 1 plastic bottle, including 3 specimens from a single glass bottle.
We also found 1 Sorex cinereus (Kerr) (Masked Shrew) in a single plastic bottle.
In collections from site #2, students discovered only the remains of 1 Sorex fumeus
(Miller) (Smoky Shrew) in 1 glass bottle. We calculated small-mammal entrapment
frequencies as 15.3% for Northern Short-tailed Shrews, 2.5% for Masked Shrews,
2.5% for Smoky Shrews, and 20.5% across all species.
Discussion
Our project demonstrates how examinations of bottles discarded along highways
can have a variety of educational applications for students interested in studying
small mammals. This technique is far less time- and labor-intensive than traditional
sampling methods such as pitfall-trapping, without any additional small-mammal
mortality (Handley and Kalko 1993). Furthermore, with minimal training, anyone
can easily perform this type of investigation, including most children, whose work
often proves as reliable as that of adults and professionals if they are adequately
supervised (Miczajka et al. 2015, Pope et al. 2016) and species identifications are
verified (Prisby and Super 2007, Roy et al. 2016).
Our project methodology can also be applied almost anywhere because discarded
bottles containing small-mammal remains occur along highways throughout much
Southeastern Naturalist
M.P. Brannon, J.K.H. Brannon, and R.C. Baird
2017
8
Vol. 16 Special Issue 10
of the US and the world (Arrizabalaga et al. 2016). Although we only investigated
2 sites in this study, sampling performed at numerous localities across a wider
geographic region could yield data that students could utilize to map distributions
of regional species (Brannon et al. 2010, Pagels and French 1987). In addition,
skeletal remains removed from bottles can function as a source of small-mammal
taxonomic and anatomical data, much like those obtained from owl pellets (Key
1996). Similar investigations could also be performed on other organisms frequently
extracted from bottles, such as species of land snails (Dourson and Dourson
2006). As citizen-scientists, students can provide many valuable contributions to
on-going environmental research (Miczajka et al. 2015, Pope et al. 2016, Prisby
and Super 2007).
Small-mammal mortality caused by entrapment in bottles discarded along
roadways is an anthropogenic effect that can be mitigated through frequent and
thorough highway cleanups, proactive enforcement of anti-littering regulations,
and increased public education (Benedict and Billeter 2004, Brannon and Bargelt
2013, Hamed and Laughlin 2015). The inclusion of students in citizen-science
projects, such as the one presented here, can further develop an awareness of
conservation issues, and can provide science education through direct experience
(Archie 2004, Prisby and Super 2007, Wyner et al. 2014). Environmental education
programs that incorporate immersive, hands-on, real-world learning experiences
using the local community and environment as a framework can increase students’
academic performance and enhance their appreciation for the natural world (Ernst
and Monroe 2004, Falco 2004, Louv 2008). Children who are exposed to nature and
receive education about environmental concerns are not only more likely to advocate
for the protection of natural areas and conservation of biodiversity as adults,
but to also take action (Bögeholz 2006, Komoroske et al. 2015, Louv 2008, Wells
and Lekies 2006). Placed-based environmental education programs, including participation
in scientific-research opportunities, can create a stronger commitment to
serving as contributing citizens of the local community and as better stewards of the
earth (Hungerford and Volk 1990, Leopold Education Project 2016, Sobel 2005).
Acknowledgments
We thank the spring 2008 middle-school faculty, staff, and students of Summit Charter
School, who participated in this project. The data they collected contributed to a 2007–2012
research study of the UNC Institute for the Environment Program at the Highlands Biological
Station in Highlands, NC.
Literature Cited
Archie, M.L. 2004. Advancing Education Through Environmental Literacy. Association for
Supervision and Curriculum Development, Alexandria, VA. 16 pp.
Arrizabalaga, A., L.M. González, and I. Torre. 2016. Small mammals in discarded bottles:
A new world record. Galemys 28:63–65.
Benedict, R.A., and M.C. Billeter. 2004. Discarded bottles as a cause of mortality in small
vertebrates. Southeastern Naturalist 3:371–377.
Southeastern Naturalist
9
M.P. Brannon, J.K.H. Brannon, and R.C. Baird
2017 Vol. 16, Special Issue 10
Bögeholz, S. 2006. Nature experience and its importance for environmental knowledge,
values, and action: Recent German empirical contributions. Environmental Education
Research 12:65–84.
Bonney, R., C.B. Cooper, J. Dickinson, S. Kelling, T. Phillips, K.V. Rosenberg, and J. Shirk.
2009. Citizen science: A developing tool for expanding science knowledge and scientific
literacy. BioScience 59:977–984.
Brannon, M.P., and L.B. Bargelt. 2013. Discarded bottles as a mortality threat to shrews
and other small mammals in the Southern Appalachian Mountains. Journal of the North
Carolina Academy of Science 129:126–9.
Brannon, M.P., M.A. Burt, D.M. Bost, and M.C. Caswell. 2010. Discarded bottles as a
source of shrew-species distribution data along an elevational gradient in the Southern
Appalachians. Southeastern Naturalist 9:781–94.
Caldwell, R.S., and H. Bryan. 1982. Notes on distribution and habitats of Sorex and Microsorex
(Insectivora: Soricidae) in Kentucky. Brimleyana 8:91–100.
Clegg, T.M. 1966. The abundance of shrews, as indicated by trapping and remains in discarded
bottles. Naturalist 899:122.
Dourson, D., and J. Dourson. 2006. Land Snails of the Great Smoky Mountains (Eastern
Region). Appalachian Highlands Learning Center at Purchase Knob and Great Smoky
Mountains National Park, Gatlinburg, TN. 55 pp.
Ernst, J.A., and M. Monroe. 2004. The effects of environment-based education on students’
critical-thinking skills and disposition towards critical thinking. Environmental Education
Research 10:507–522.
Falco, E.H. 2004. Environment-based education: Improving attitudes and academics for
adolescents. South Carolina Department of Education, Columbia, SC. 10 pp.
Feinstein, N., S. Allen, and E. Jenkins. 2013. Outside the pipeline: Reimagining science
education for nonscientists. Science 340:314–317.
Gerard, A.S., and G.A. Feldhamer. 1990. A comparison of two survey methods for shrews:
Pitfalls and discarded bottles. American Midland Naturalist 124:191–194.
Hamed, M.K., and T.F. Laughlin. 2015. Small-mammal mortality caused by discarded
bottles and cans along a US Forest Service road in the Cherokee National Forest. Southeastern
Naturalist 14:506–516.
Handley, C.O., Jr., and E.K.V. Kalko. 1993. A short history of pitfall trapping in America,
with a review of methods currently used for small mammals. Virginia Journal of Science
44:19–26.
Hart, R.A. 1997. Children’s Participation: The Theory and Practice of Involving Young
Citizens in Community Development and Environmental Care. UNICEF, New York,
NY. 208 pp.
Hungerford, H., and T. Volk. 1990. Changing learner behavior through environmental education.
Journal of Environmental Education 21:8–21.
Johnston, D.W. 1967. Ecology and distribution of mammals at Highlands, North Carolina.
Journal of the Elisha Mitchell Scientific Society 83:88–98.
Key, J.P. 1996. Resource Manual for Owl-Pellet Labs: Reproducible Charts and Activities
to Enhance Owl-Pellet Studies. White Owl Enterprises, Winona, MS. 22 pp.
Kolenda, K., K. Kurczaba, and M. Kulesza. 2015. Littering as a lethal threat to small animals.
Przegląd Przyrodniczy 26:53–62.
Komoroske, L.M., S.O. Hameed, A.I. Szoboszlai, A.J. Newsom, and S.L. Williams. 2015.
A scientist’s guide to achieving broader impacts through K–12 STEM collaboration.
BioScience 65:313–322.
Southeastern Naturalist
M.P. Brannon, J.K.H. Brannon, and R.C. Baird
2017
10
Vol. 16 Special Issue 10
Laerm, J., W.M. Ford, and B.R. Chapman. 2000. Conservation status of terrestrial mammals
of the southeastern United States. Occasional Papers of the North Carolina Museum of
Natural Sciences NC Biological Survey 12:4–16.
Leopold Education Project. 2016. Lesson in a Land Ethic. The Aldo Leopold Foundation,
Baraboo, WI. 83 pp.
Louv, R. 2008. Last Child in the Woods: Saving Our Children from Nature-Deficit Disorder.
Algonquin Books, New York, NY. 323 pp.
Miczajka, V.L., A-M. Klein, and G. Pufal. 2015. Elementary school children contribute to
environmental research as citizen scientists. PLoS One 10:e0143229.
Morris, P.A., and J.F. Harper. 1965. The occurrence of small mammals in discarded bottles.
Proceedings of the Zoological Society of London 145:148–153.
National Governors Association (NGA). 2012. Issue brief: The role of informal science in
the state education agenda (executive summary). Washington, DC. 2 pp.
Pagels, J.F., and T.W. French. 1987. Discarded bottles as a source of small-mammal distributional
data. American Midland Naturalist 118:217–219.
Pope, K.L., G.M. Wengert, J.E. Foley, D.T. Ashton, and R.G. Botzler. 2016. Citizen scientists
monitor a deadly fungus threatening amphibian communities in northern coastal
California, USA. Journal of Wildlife Diseases 52:516–523.
Prisby, M., and P. Super. 2007. The Director’s Guide to Best Practices: Programming–Citizen
Science. Association of Nature Center Administrators, Logan, UT. 52 pp.
Roy, H.E., E. Baxter, A. Saunders, and M.J.O. Pocock. 2016. Focal-plant observations as a
standardized method for pollinator monitoring: Opportunities and limitations for mass
participation citizen science. PLoS One 11:e0150794.
Sobel, D. 2005. Place-based Education: Connecting Classrooms and Communities, 2nd Edition.
Nature Literacy Series Number 4, The Orion Society, Great Barrington, MA. 116 pp.
Wells, N.M., and K.S. Lekies. 2006. Nature and the life course: Pathways from childhood
nature experiences to adult environmentalism. Children, Youth, and Environments
16:1–24.
Wyner, Y., J. Becker, and B. Torff. 2014. Explicitly linking human impact to ecological
function in secondary school classrooms. The American Biology Teacher 76:508–515.