The Northern Goshawk – A Key Species in the Great Bear Rainforest

Publication - August 18, 2010
The fierce, raven-sized northern goshawk, coastal subspecies laingi, is a bird of prey that relies on mature and old growth coastal temperate rainforests for foraging and breeding. The northern goshawk forages for forest birds and small mammals like squirrels within enormous home ranges, each of roughly 9,000 hectares (roughly the size of 16,000 football fields) in the Great Bear Rainforest.

The northern goshawk plays an important role in coastal ecosystems. As a top predator, it is thought to play a critical role in the food chain by regulating prey populations. This key species is also an ‘ecosystem engineer’: each breeding pair builds and maintains between three and nine nests within its home range, but uses only one per year. The remaining nests are used by other birds like forest owls, ravens, and Great Blue Herons, many of which can’t build their own nests.

There are estimated to be fewer than 400 breeding pairs of northern goshawk (subspecies laingi) in all of BC, representing 50% of the world’s population of this subspecies. The Great Bear Rainforest includes 50% of the BC range for this subspecies but is thought to include only about 20% of its breeding pairs. Yet typically at least 2500 adult individuals are needed to maintain viable

populations of birds. The northern goshawk is vulnerable to the logging of old growth and mature forests, and is listed as threatened (red-listed) by the BC Conservation Data Centre, the Canadian government, and international authorities. 

SOME INTERESTING FACTS

  • the northern goshawk can be very persistent in going after its prey. As an example, a goshawk was seen chasing a snowshoe hare for 45 to 60 minutes along a hedgerow
  • the name "goshawk" is derived from the Old English words gos, which means goose (though they do not hunt geese), and hafoc meaning hawk (‘goshawk’ is pronounced as 2 separate words: gos-hawk)
  • the subspecies laingi of the northern goshawk described here and resident in the Great Bear Rianforest is also known as the Queen Charlotte Goshawk
  • the ‘bushy’ white feathers above each eye is thought to protect its eyes when it dives into thick brush to hunt prey
  • the northern goshawk as a long wedge-shaped tail which functions as a rudder allowing it to make sharp right turns through trees

SOURCES

Cornell Lab of Ornithology – All About Birds, online at http://www.allaboutbirds.org/guide/Northern_Goshawk/lifehistory

Doyle, F. I. 2005. Breeding success of the goshawk (A. gentilis laingi) on Haida Gwaii/Queen Charlotte Islands 2005: is the population continuing to decline? Wildlife Dynamics Consulting, Telkwa, BC. Unpublished report.10

Northern Goshawk Accipiter gentilis laingi Recovery Team. 2008. Recovery strategy for the Northern Goshawk, laingi subspecies (Accipiter gentilis laingi) in British Columbia. Prepared for the B.C. Ministry of Environment, Victoria, BC. 56 pp., online at: www.env.gov.bc.ca/wld/documents/recovery/rcvrystrat/northern_goshawk_rcvry_strat_200508.pdf

Traill , L. W. Bradshaw, C. J. A., and B. W. Brook. 2007. Minimum viable population size: a meta-analysis of 30 years of published estimates. Biological Conservation 139:159-166. 

Zipcodezoo.com, http://zipcodezoo.com/Animals/A/Accipiter_gentilis/

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