|Forest Investment Account (FIA) - Land Base Investment Program|
|FIA Project 6746004|
|Northern Goshawk Nest Monitoring in TFL 19|
|Project lead: Sandford, Jeff (Western Forest Products Inc.)|
|Contributing Authors: Manning, E. Todd; Chytyk, Paul|
|Subject: Forest Investment Account (FIA), British Columbia|
|Series: Forest Investment Account (FIA) - Land Base Investment Program|
|The coastal subspecies of Northern Goshawk (Accipiter gentilis laingi) is an uncommon forest raptor that is currently on the British Columbia Red List as a candidate species for Endangered or Threatened status. It is also an Identified Wildlife Management Species under the BC Forest and Range Practices Act. Federally, A. g. laingi is listed as Threatened by the Committee on the Status of Endangered Wildlife in Canada. Population trends of this subspecies are unknown in British Columbia, but the subspecies was listed due to its estimated small populations size (<1000 mature individuals) and threats to populations from forest harvesting.|
In Western Forest Products Inc. (WFP) TFL 19, 12 nest trees in 6 confirmed breeding territories (Bolton Lake, Conuma River, Muchalat Lake, Oktwanch River, Twaddle Lake, and Ucona River), were located between 1997 and 2002 by BC Ministry of Environment surveys. In Gold Muchalat and Strathcona Provincial Parks, 8 nest trees in 3 confirmed breeding territories (Gold Muchalat, Cervus Creek and Lupin Falls) were also located between 1995 and 2001 by Ministry of Environment. In 2008, Manning, Cooper and Associates Ltd. Were contracted to monitor these 9 goshawk territories to determine their current activity status. Between 9-22 June and 8-23 July 2008, surveys to determine the breeding activity status were conducted. All known territories were visited at least twice during the survey period, once during the nestling period (9-22 June) and once during the fledgling period (8-23 July). All surveys followed Resource Inventory Standards Committee standards for raptor surveys, and consisted mainly of call playback and nest search surveys.
A total of 77 call playback stations (57 in TFL 19 and 20 in parks) were completed during the survey period in 2008. Estimated hours surveyed in each known nest territory ranged from 4.5-12.0 hrs, depending on the size of the area surveyed and whether or not there were any previous indications of occupancy. Total crew hours spent conducting goshawk surveys was approximately 78.0 hrs (50.0 hrs in TFL 19 and 28.0 hrs in parks). One out of six of the monitored territories in TFL 19 (Ucona River) had goshawk detections, while 2 out of 3 territories in parks (Cervus Creek and Lupin Falls) had goshawk detections during surveys in 2008. Goshawk detections resulted in two active nests being located in Ucona River (TFL 19) and Cervus Creek (BC Parks) territories. One of the six known goshawk nest territories (Ucona River) was active and successful in 2008 in TFL 19, while one out of three goshawk territories surveyed in BC Parks (Cervus Creek) was active and successful. Both active goshawks nests in these two territories produced 2 young in 2008. Lupin Falls territory in Strathcona Provincial Park was occupied, but inactive. The six monitored goshawk nest territories in TFL 19 had an occupancy rate of 16.7%, while the three goshawk nest territories in parks had an occupancy rate of 66.7% in 2008.
Including the 2008 surveys, there are now 13 known nest trees in six confirmed oshawk nest territories in TFL 19, and 11 known nest trees in three confirmed goshawk nest territories in provincial parks on north-central Vancouver Island. Four new nests were found during surveys in 2008: Ucona River (new) Nest #4 (TFL 19), Cervus Creek (new) Nest #5 (Strathcona Provincial Park), and two old nests (previously undiscovered) in Gold Muchalat Provincial Park (Nests #4 and
#5). 2008 Northern Goshawk Monitoring of BC Parks and WFP Inc. TFL 19, Gold River, British Columbia Manning, Cooper and Associates Ltd. Dec. 2008
ii Two other raptor species, red-tailed hawk and merlin were detected during goshawk surveys in TFL 19 and the two provincial parks in 2008. A red-tailed hawk was on territory in the Bolton Lake goshawk territory in TFL 19; no nest was found. Another red-tailed hawk was observed flying over the Conuma River goshawk territory in TFL and was presumed to be foraging. A merlin and a goshawk at Cervus Creek simultaneously held territories in the same nest stand. Known goshawk nest territories were monitored in two other study areas on northern Vancouver Island in 2008, TFL 37 and Timber Supply Area (TSA) 37. TFL 37, centered around the town of
Woss, had 6 of 12 (50.0%) surveyed nest territories occupied. British Columbia Timber Sales (BCTS) TSA 37, located northwest of Campbell River had 2 of 9 (22.2%) known goshawk nest territories occupied. The mean occupancy for all areas surveyed in 2008 was 38.9%; the occupancy rate for TFL 19 (16.7%) was the lowest among the areas surveyed. Nest productivity in other monitored study areas on northern Vancouver Island in 2008 was 2.8 fledglings/active territory in TFL 37 (Woss), and 1.5 fledglings/active territory in TSA 37 (Campbell River). Mean productivity among the four study areas (TFL 19, TFL 37, BC Parks, TSA 37) was 2.1 fledglings/active territory; mean productivity for TFL 19 and BC Parks territories (2.0) was very near the 2008 average.
|Final report (2.3Mb)|
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Updated August 16, 2010
Please direct questions or comments regarding publications to For.Prodres@gov.bc.ca