Clutch size: 3-5 eggs
Incubation period: 27 days
Nestling period: 55-65 days
life expectancy: about 10 years, oldest 18 years.
Juvenile mortality: about 75%
Flight speed: about 40 km/h in calm air
Great Blue Heron is a widespread year round resident of the
Pacific Coast of North America. It lives along the seashore from
southern Alaska to Baja California and across North American from
southern Canada to northern Mexico. Herons depart parts of Canada
and northern United States that freeze in winter for the southern
USA, Mexico, the Caribbean, Central America or northern South
Pacific Coast has two subspecies of Great Blue Heron. Ardea
herodias fannini resides year round along the northeast coast
of the Pacific. In a paper published in the 2004 volume of
Northwest Naturalist, Bob Dickerman suggested that A. h.
fannini should be restricted to the Queen Charlotte Islands
and southeast Alaska. He based his conclusion on measurements and
plumage colouration. The Queen Charlotte Island heron is the
smallest and darkest of the coastal subspecies. If accepted, the
heron along the south coast of British Columbia and Washington
will need to be renamed. He also suggested that the Oregon and
California coast herons are the subspecies A. h. herodias
which is found across the continent. He did not consider the Great
Blue Heron on the Galapagos. There will soon be some DNA analysis
of coastal herons to examine the taxonomy further.
10,000 herons reside along the Pacific Coast between Washington
and Alaska. Many thousand likely reside along the coast of
California and a few thousand probably live on the Oregon coast.
The northwest coast subspecies has been most studied in recent
Butler, R.W. 1997. The Great Blue Heron. University
of British Columbia Press, Vancouver.
Butler, R. W. 1992. Great Blue Heron, Ardea herodias. Birds
of North America No. 25, American
Dickerman, R. W. 2004. Characteristics and distribution of
Ardea herodias fannini with comments on the effect of washing
on the holotype. Northwestern Naturalist 85: 130-133.
Vennesland, R. W. 2000. The effects of disturbance from humans and
predators on the breeding decisions and productivity of the Great
Blue Heron in south-coastal British
Columbia. M. Sc. Thesis, Simon Fraser University, Burnaby,
Blue Heron Links
more information on the conservation of the coastal heron click on
web cam in Beacon Hill Park, Victoria, British Columbia
on the biology and a video of foraging and nesting herons