Marjorie Sorensen

Movement Ecology Group


Dr. Marjorie Sorensen

Postdoctoral Researcher (Alumni)


Ecosystem functioning and animal movement

My research examines the relationships between animal movement and ecosystem functioning. Given that fragmentation of forests continues at a rapid pace I aim to understand the functional connectivity provided by seed dispersers in fragmented landscapes, and to predict the consequences of increased future fragmentation for seed dispersal. I am currently using simulation models in combination with empirical data to tackle these questions. Previously, I have worked on understanding the winter ecology of long-distance migratory birds.  While research into breeding ecology is common, once birds depart for autumn migration our understanding of their basic ecology and the factors that affect individual success is limited. I studied Pacific seabirds on the west coast of Canada to understand how winter diet affected subsequent breeding success, and Palearctic-African migratory songbirds in Zambia to help demystify some aspects of their winter ecology.


Sorensen, M.C., Jenni-Eiermann, S., Spottiswoode, C.N. (2016) Why do migratory birds sing on their tropical wintering grounds? American Naturalist, doi: 10.1086/684681.

Sorensen, M.C., Asghar, M., Bensch, S., Fairhurst, G., Jenni-Eiermann, S., Spottiswoode, C.N. (2016) A rare study from the wintering grounds provides insight into the costs of malaria infection for migratory birds. Journal of Avian Biology. 47, 001-008.

El-Arabany, N., Sorensen, M.C., Hansson, B. (2015) Inferring the links between breeding and wintering grounds in a Palearctic–African migratory bird, the Great Reed Warbler, using mitochondrial DNA data. African Zoology 50, 241-248.

Carter, A.J., Horrocks, N.P.C., Huchard, E., Logan, C.J., Lukas, D., MacLeod, K.J., Marshall, H.H., Peck, H.L., Sanderson, J.L., Sorensen, M.C. (2014) Junior scientists are skeptical of sceptics of open access: a reply to Agrawal. Trends in Plant Science 19, 339-340. 

Sorensen, M.C. (2014) Singing in Africa: no evidence for a long supposed function of winter song in a migratory songbird. Behavioral Ecology 25: 909-915.

Sorensen, M.C., Hipfner, J.M., Kyser, T.K. & Norris, D.R. (2010) Pre-breeding diet and ornament size in the Rhinoceros Auklet Cerorhinca monocerata. Ibis 152: 29-37.

Sorensen, M.C., Hipfner, J.M., Kyser, T.K. & Norris, D.R. (2009) Carry-over effects in a Pacific seabird: stable isotope evidence that pre-breeding diet quality influences reproductive success. Journal of Animal Ecology 78: 460-467.