Northern Prairie Wildlife Research Center
At 1510 hr on 13 May 1999, we observed a female hooded merganser (Lophodytes cucullatus) with seven Class Ia (1 to 6 day old) ducklings (Gollop and Marshall 1954). The female and her brood were sighted near a nest box on the James River at Northern Prairie Wildlife Research Center (NPWRC), Stutsman County, North Dakota (T139N, R63W, NE1/4, Sec. 9). As we approached, the female and her brood swam upstream and disappeared behind fallen timber and overhanging vegetation.
Nest boxes were erected along the James River at NPWRC in 1968 as part of a program to encourage wood duck (Aix sponsa) nesting (B. Hanson, U.S. Geological Survey, Jamestown, ND, unpubl. data). While monitoring nest-box use during 1995 to 1999, TKB found that hooded mergansers occupied 26% of 22 to 30 available nest boxes. Nest boxes were only checked after the nesting season, however, so hatch dates were unknown.
Hatch dates for hooded mergansers have rarely been documented in North Dakota. Published accounts of a few checks made during the nesting season indicated that some nests hatched before 18 June (Bent 1901) and others hatched after 8 July (Stewart 1975). In a five-year study of nest-box use in northern Minnesota, at a latitude similar to NPWRC, the range of hatch dates recorded for 68 nests was 25 May to 15 July (Zicus 1990).
Hooded mergansers have an average laying rate of 0.5 egg per day (Morse et al. 1969, Zicus 1990) and an incubation period of approximately 32 days (Bellrose 1980). By back dating, we estimated that the brood we observed had hatched between 8 and 13 May from a clutch initiated between 23 and 28 March. These nesting dates are consistent with the relatively early appearance of hooded mergansers at NPWRC in 1999. The species was first observed on 11 March 1999, 5 to 28 days earlier than in 1992 to 1998, the years for which phenology records are available at NPWRC (L. D. Igl, U.S. Geological Survey, Jamestown, ND unpubl. data).
Our 13 May brood observation helps to document the beginning of the nesting season for hooded mergansers in North Dakota. Our observation also might represent an unusually early nest for the species in southeastern North Dakota.
We thank J. Dechant, L. Igl, and P. Pietz for reviewing the manuscript.
Bellrose, F. C. 1980. Ducks, geese and swans of North America. Third edition. Stackpole Books, Harrisburg, PA.
Bent, A. C. 1901. Nesting habits of the Anatidae in North Dakota. Auk 18:328-336.
Gollop, J. B., and W. H. Marshall. 1954. A guide for aging duck broods in the field. Mississippi Flyway Council Technical Section Report.
Morse, T. E., J. L. Jakabosky, and V. P. McCrow. 1969. Some aspects of the breeding biology of the hooded merganser. J. Wildl. Manage. 33:596-604.
Stewart, R. E. 1975. Breeding birds of North Dakota. Tri-college Center for Environmental Studies, Fargo, ND.
Zicus, M. C. 1990. Nesting biology of hooded mergansers using nest boxes. J. Wildl. Manage. 54:637-643.
This resource is based on the following source (Northern Prairie Publication 1149):
Buhl, Thomas K., and Terry L. Shaffer. 2000. Early nesting record of hooded merganser in North Dakota. Prairie Naturalist 32(4): 245-246.
This resource should be cited as:
Buhl, Thomas K., and Terry L. Shaffer. 2000. Early nesting record of hooded merganser in North Dakota. Prairie Naturalist 32(4): 245-246. Jamestown, ND: Northern Prairie Wildlife Research Center Online. http://www.npwrc.usgs.gov/resource/birds/hoodmerg/index.htm (Version 30SEP2002).