Susan McRae

Title: Teaching Associate Professor
Area of Study: Behavioral and Evolutionary Ecology of Birds
Fax: 252-328-4178
Office: Howell S210
Address: Department of Biology
East Carolina University
Greenville, NC 27858

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Research Interests:

I am broadly interested in the evolution of sociality. Social systems are the products of behavioral strategies of individuals. I study how conflicts of interest arising from group-living are resolved through the evolution of alternative behavioral strategies. My studies have focused on parent-offspring conflict, reproductive parasitism, and other conflicts arising from sociality. I am particularly interested in how ecological, social and genetic factors interact in shaping the evolution of parasitic and cooperative breeding strategies. Measuring kinship is fundamental to understanding conflicts of interest. My research integrates field observation and experimental work on populations of marked individuals with molecular genetic determination of relatedness. In one project, I study how ecological factors affect the evolution of conspecific brood parasitism in the common moorhen. Host responses to brood parasitism are expected to vary in relation to the risk of parasitism and the cost of parasitism to the host. One principal question is: Among populations with varying rates of conspecific brood parasitism, are host responses predictable from ecological, genetic and social factors?

Behavior and evolution of female mimic ruff sandpipers


Since 2006, I have collaborated with David Lank (Simon Fraser University, Canada) investigating the evolution and behavior of female mimics among ruff sandpipers. Male ruff sandpipers come in three flavors: Independents with dark ruff plumages, defend territories (courts) on the mating arena, Satellites with white ruff plumages move among these courts and co-display, while Faeders (female mimics) are smaller, have female-like plumage and behave as sneakers. We conducted breeding experiments in aviaries at Simon Fraser University to look at the behavior and evolution of this morph. Collaborating with colleagues from the U.K. working on the genomics of ruff morphs, we discovered that the genetic basis for these extraordinary reproductive strategies is a chromosomal inversion or 'supergene'. For details:

Conservation is a strong motivation for my research, and I am becoming increasingly involved in local avian projects (see below) and through ECU's agreement with Sylvan Heights Bird Park:


King Rail Conservation Project


Since 2011, my students and I have been studying King Rails Rallus elegans, a rare and declining secretive marshbird. Wetlands are among the most productive ecosystems and provide habitat for up to 85% of North America's migratory bird species. Wetland destruction across much of the King Rail's range has led to the decline of this and other marsh bird populations. The King Rail is the fastest declining hunted rail species, listed in the North American Conservation Action Plan as a species of 'high concern', and globally as 'Near Threatened' by BirdLife International. Due to the bird's secretive nature, infrequent vocalizations, cryptic plumage, and occupancy of densely vegetated wetlands, little is known about the King Rail's behavior, demography or habitat use. We have begun to redress this by studying a breeding population at Mackay Island National Wildlife Refuge Though making inferences about population size, dispersal, recruitment, and survival rates is challenging, we have been making inroads through a combination of field monitoring and experiments, complemented by genetic analysis of population structure.


Behavior, Ecology and Genetics of the Eastern Bluebird


Since 2010, my students and I have been monitoring Eastern Bluebirds nesting at ECU's West Research Campus. We are examining long-term seasonal trends in reproductive success, and life history variables (timing of breeding, clutch size, hatching and fledging rates), as well as site fidelity and recruitment. Becoming a field assistant on this project is an excellent way for undergraduates to learn techniques in field ornithology. Several students have developed their own Honors Thesis projects on this system. Interested biology majors are encouraged to inquire, but please only do so if you are willing to commit to working on the project during through the summer semesters. In part, this is a conservation project as well: Eastern Bluebird populations are coming back having declined. They are limited by breeding sites due to shortage of nest cavities and competition from introduced European Starlings. We use 'Homes for Bluebirds' ( Bailey, NC) nest boxes that are built to exclude starlings and cowbirds.

Selected Publications (student authors denoted by *):

*Clauser, A.J. and S.B. McRae 2016. Plasticity in incubation behavior and shading by king rails ( Rallus elegans) in response to temperature. Journal of Avian Biology doi: 10.1111/jav.01056

*Clauser, A.J. and S.B. McRae 2016. King rails ( Rallus elegans ) vary building effort and nest height in relation to water level. Waterbirds (accepted, in press, September issue)

Küpper, C., Stocks, M., Risse, J.E., dos Remedios, N., Farrell, L.L., McRae, S.B., Morgan, T.C., Karlionova, N., Pinchuk, P., Verkuil, Y.I., Kitaysky, A.S., Wingfield, J.C., Piersma, T., Zeng, K., Slate, J., Blaxter, M., Lank, D.B. and T. Burke 2015. A supergene determines highly divergent male reproductive morphs in the ruff. Nature Genetics doi:10.1038/ng.3443

*Bade, L.M., Balakrishnan, C.N., Pilgrim, E.M., McRae, S.B. and J.J. Luczkovich. 2014. A genetic technique to identify the diet of cownose rays, Rhinoptera bonasus: analysis of shellfish prey items from North Carolina and Virginia.  Environmental Biology of Fishes doi: 10.1007/s10641-014-0290-3

*Farrell, L.L., T. Burke, J. Slate, S.B. McRae and D.B. Lank 2013. Mapping the female mimic morph locus on the microsatellite linkage map of the ruff. BMC Genetics 14:109 DOI: doi:10.1186/1471-2156-14-109

Lank D.B., *Farrell L.L., Burke T., Piersma T. and S.B. McRae 2013.  A dominant allele controls development into female mimic male and diminutive female ruffs.  Biology Letters 20130653 doi: 10.1098/rsbl.2013.0653

*Brackett, C.L., *Maley, J.M., Brumfield, R.T. and S.B. McRae 2013. Characterization of microsatellite loci for a threatened species, the King Rail, Rallus elegans, using a next-generation sequencing protocol. Conservation Genetics Resources 5:1189-1191. DOI: 10.1007/s12686-013-9999-0

McRae, S.B. 2011. Conspecific brood parasitism in the tropics: an experimental investigation of host responses in common moorhens and American purple gallinules. Ecology and Evolution 1(3): 317-329.     DOI: 10.1002/ece3.26

*Stang, A.T. and S.B. McRae 2009. Why some rails have white tails: the evolution of white undertail plumage and anti-predator signaling. Evolutionary Ecology 23:943-961.

McRae, S.B., Emlen, S.T., *Rubenstein, D.R. and S.M. Bogdanowicz 2005. Polymorphic microsatellite loci in a plural breeder, the grey-capped social weaver ( Pseudonigrita arnaudi), isolated with an improved enrichment protocol using fragment size selection. Molecular Ecology Notes 5:16-20.

Jamieson, I.G., McRae, S.B., *Trewby, M. and R.E. Simmons 2000.  High rates of conspecific brood parasitism and egg rejection in coots and moorhens in ephemeral wetlands in Namibia. The Auk 117: 250-252.

Kokko, H. and S.B. McRae 2000. Take care when studying parenting behaviour. Trends in Ecology and Evolution 15:440-441.

All publications through Research Gate

Courses Taught:

BIOL 1200 Principles in Biology II (2001 - present) Fall

BIOL 1201 Principles in Biology II, Lab Coordinator (Aug. 2002 - 2008), Faculty Advisor (2008 - present)

BIOL 3240, 3241 Field Zoology, Field Zoology Lab (2010 - present), Spring, even years

BIOL 3740, 3741 Animal Behavior, Animal Behavior Lab (2007 - present) Fall

BIOL 4400 Terrestrial Field Ecology: Summer Study Abroad in Panama (2009 - present)

BIOL 4995 Biology Honors Thesis (Coordinator) Fall, Spring

BIOL 4770/6770, 4771/6771 Ornithology, Ornithology Lab (2000 - present) Spring

Laboratory Personnel

M.S. Students

Katie Schroeder


Katie Schroeder (schroederk15 at students dot ecu dot edu)

MS Candidate

Katie is interested in evolution of vocal communication and how it relates to social interactions. Her thesis focuses on the structure and function of king rail calls, as well as factors affecting rail detection probability using call broadcast versus autonomous recording units (ARUs).

Current Undergraduates:

Caroline Balch
Emma Cunningham
William Zahran

Laboratory Alumni:

Amanda Clauser

 Amanda Clauser, MS 2015

Amanda’s thesis examined the effect of thermal stress and water level variation on parental behavior and nest success

Carol Brackett

Carol Brackett, MS 2013   

Carol developed species-specific genetic markers to look at king rail mating strategies and reproductive success

Jan Kolts

Jaan Kolts, MS 2014

Jaan radio-tracked king rails to determine home range size, movement patterns and habitat preferences.

He is an ecological consultant with J.H. Carter III & Assoc. Inc. Environmental Consultants in Southern Pines, N.C. 


Debbie Mauney, MS 2009

Debbie studied brood sex ratios in the common moorhen

She is Avian Clinic Director at the Center for Birds of Prey in Charleston, S.C. 

Undergraduate Alumni

(this is just a sampling of the many talented undergraduates that have passed through the lab, and gone on to do great things!)

Olivia Green - BS 2015, Metrics Inc. pharmaceuticals
Nicholas Nees -  BS 2013, Aviculture specialist, Sylvan Heights Bird Park
Kat Lewandowski -  BS 2013, Aviculture specialist, Sylvan Heights Bird Park
Matthew Edwards - BS 2013, Honors in Biology, BSOM medical student
Erica Nassar - BS 2012, ECU Cultural Ambassador, Spain; MA Public Health, Universidad de Granada, Spain
William Davis  - BS 2012, Honors in Biology, ECU MAT, High School Science Teacher
Claire Bawtinhimer - BS 2011, Alaska SeaLife Center Zoologist
Melorah Brackley - MS  BS 2011, ECU MS Biology 2012; PhD candidate
Farrah Forney, RN  - BS 2010, Honors in Biology, ECU MS Nursing; Registered Nurse Practitioner
Hannah Tomczak - BS 2008, Research Technician, Univ. of Pennsylvania, Dept. of Anaesthesia
Susan Ratcliffe Canady - BS 2008, Metrics Inc. pharmaceuticals
Carlyle Rogers, PhD  - BS 2008, PhD Pharmacology 2013; ECU Office of Research Innovation
Emily Bruckner - BA 2007, BA Psychology, ECU; US Air Force Airman of the Year, 2008, Air Force Reserve Command's Outstanding Civil Engineer Manager of the Year, 2010; Movement Mortgage LLC
Mark Dobransky, DMD - BS 2007, Vaccine manufacture specialist, DSM Pharmaceuticals; ECU Dentistry class of 2016
Haley Cleckner, MA - BS (Univ. Honors, Magna cum laude) 2008; MA Geography, ECU 2010, Charlotte Int'l Airport GIS specialist
Charles Hoots, DVM  - BS 2006; Cornell University Veterinary College 2010; Veterinarians Without Borders
Alexandra Stang, MD -  BS (Univ. Honors, Summa cum laude) 2006; MD, BSOM 2012; 2015 ECU Physicians, Internal Medicine and Infectious Disease Specialist