Black Brant and Zostera - Goose-plant interaction in a dynamic coastal system

The objectives of this study are founded on the working hypothesis that brant are grazing specialists that manipulate favored food stocks in such a way that optimizes foraging opportunities upon return to previously grazed sites. We predict therefore that Zostera communities and the black brant population interact on a temporal and spatial scale.

There are four primary objectives in this study:

  • develop a temporal and spatial description of Zostera quality and abundance
  • describe seasonal and annual Zostera phenology
  • identify potential anthropogenic and natural factors responsible for variation in Zostera quality and abundance
  • develop a temporal and spatial description of goose foraging distribution in relation to Zostera quality and abundance

Colleagues from Alaska have fitted black brant with tarsal bands that are readable with a telescope. Students will be encouraged to find and record individually marked black brant. In particular, participation will be expected from students in Waterfowl 420.

  • For more information about these bands and how you can help record data, scroll down


Shaughnessy FJ, Ferson SL, Frimodig AJ, Barton DC, Hurst M & Black JM 2021. Growth and flowering responses of eelgrass to simulated grazing and fecal addition by brant geese. Ecosphere

Stillman RA, Wood KA, Gilkerson W, Elkinton E, Black JM, Ward DH, & Petrie M 2015. Predicting effects of environmental change on a migratory herbivore. Ecosphere 6:art114.

Elkinton E, Lo L & Black JM 2013. Black Brant Branta bernicla nigricans forage at both tides on Humboldt Bay, California, USA. Wildfowl Special Issue 3, 90-103.

Spragans KA, Bjerre ER & Black JM 2013. Black Brant Branta bernicla nigricans grit acquisition at Humboldt Bay, California, USA. Wildfowl Special Issue 3, 104-115.

Shaughnessy FJ, Gilkerson G, Black JM, Ward DH, & M Petrie 2012. Predicted Zostera marina response to sea level rise and availability to foraging black brant in Pacific coast estuaries. Ecological Applications22, 1743-1761.

Black JM, Lee DE & Ward D 2010. Foraging home ranges of black brant Branta bernicla nigricans during spring stopover at Humboldt Bay, California, USA. Wildfowl 60, 85-94.

Lee DE, Black JM, Moore JE & Sedinger JS 2007. Age-specific stopover ecology of black brant at Humboldt Bay, California. Wilson Journal of Ornithology 119, 9-22.

Moore J & Black JM 2006. Slave to the tides: spatio- temporal foraging dynamics of spring staging black brant. Condor 108, 661–677.

Moore J & Black JM 2006. Historical changes in brant Branta bernicla nigricans use on Humboldt Bay, California. Wildlife Biology 12, 151-162.

Ward D, Reed A, Sedinger J, Black JM, Dirkson D & Castelli D 2005. North American Brant: effects of changes in habitat and climate on population dynamics Global Change Biology 11, 869-880.

Moore, J, Colwell M, Mathis R & Black JM 2004. Staging of Pacific flyway brant in relation to eelgrass abundance and site isolation, with special consideration of Humboldt Bay, California. Biological Conservation 115, 475-486.

Lee DE, Hamman MG & Black JM 2004. Grit-site selection of black brant: particle size or calcium content? Wilson Bulletin 116, 304-313.

Reading Black Brant Tarsal Bands

Color code combinations
Report brant tarsal bands