Western Screech-Owl Conservation and Management for the Bridge-Seton Area

2012 Survey - Final Report

Prepared For: Fish and Wildlife Compensation Program & Habitat Conservation Trust Foundation

Prepared By: Jared Hobbs M.Sc./RPBio - MFLNRO

Prepared: March 6, 2013

Fraser River Western Screech-Owl Conservation and Management

Acknowledgements

The Western Screech-Owl Conservation and Management project was initiated in 2012 through funding provided by the Fish and Wildlife Compensation Program (FWCP) and by the Habitat Conservation Trust Fund (HCTF) with support from the British Columbia (BC) Ministry of Forests, Lands and Natural Resource Operations (MFLNRO).

First and foremost, I would like to thank all of the technicians that contributed to the project’s success including: Chris Chutter, Amanda Lacika, Ellen Hancock, Jocelyn Garner, Susan Dulc and Jess Findley. Your tireless efforts, willing enthusiasm and happy spirits were all greatly appreciated by me and all of the community members you interacted with. A special extension of gratitude is due to Amanda Lacika for working diligently to ensure the data was entered and ‘cleaned’. Other key project participants included MFLNRO staff member, Byron Woods, for providing GIS support and Joanne Nielson from BC Conservation Foundation (BCCF) who was an invaluable asset as project coordinator. Thanks are also due to Myke Chutter (MFLNRO) for providing thorough and thoughtful review of this report.

I wish to thank the St’at’imc and all First Nation Tribes for allowing us access to their lands, welcoming us into their communities, and providing letters of support for the project. In particular, I am indebted to Larry Casper and Matt Manuel from the Lillooet Tribal Council (LTC) and Gerald Michell of the Bridge River Indian Band.

I thank Vivian Birch-Jones and Ian Routley (from the Lillooet Naturalist Society) for assisting us with logistical support, and for providing such a warm welcome into their community. Thanks are also due to the Scheller’s and the Barton’s for welcoming us onto their property and showing a keen interest in the project. Thanks also to the Hancock family from “Hay Meadow Honey” in Dog Creek for giving us a pleasant and warm welcome. Thank you to all other landowners, whose names remain in confidence, who also allowed us access to their properties.

Finally, and most importantly, thanks to the owls for sharing your secrets!

Fraser River Western Screech-Owl Conservation and Management

Executive Summary The interior subspecies of Western Screech-Owl (Megascops kennicottii macfarlanei) is listed as endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC 2002) and is listed on Schedule One of the Canadian federal Species at Risk Act (SARA). In BC, the M.k.macfarlanei subspecies is blue-listed by the British Columbia (BC) Conservation Data Center and is recognized as a “Priority 1” status for Goal Three (Maintain diversity of native species and ecosystems) by the BC Conservation Framework.

A comprehensive survey of all high suitability habitat within the project area was conducted in 2012. Funds were provided by the Fish and Wildlife Compensation Program and the Habitat Conservation Trust Foundation. This initiative was supported, in principle, by the St’at’imc Nation, the Lillooet Tribal Council and the Lillooet Naturalist Society.

Sixty –two areas were surveyed, including 41 areas in the Thompson-Nicola region (Region 3) and 21 in the Cariboo region (Region 5). Surveys were completed in two stages: April 7-June 28 and August 23- September 27. This approach was employed to take advantage of periods of peak responsiveness in screech-owls and to avoid expending effort (and resources) during the less responsive phenological phases of the owl’s reproductive cycle (July/August). A total of 741 call playback stations were completed during a total of 77 nights of survey.

In total, 63 screech-owls were detected at 26 sites. Nineteen sites represented ‘new’ (previously unrecorded) screech-owls; seven sites were known from previous survey and reconfirmed to be still active in 2012. Five nests were detected and young were confirmed to have fledged from seven sites (three of the nest sites plus four sites at which the nest was not found).

The addition of 19 new territories, discovered during the 2012 surveys along the Fraser River, raises the current total number of known interior screech-owl sites to 62 confirmed sites in the Thompson-Fraser Western Screech-Owl population (this population extends east to Chase and south to Merritt). Sixty-five percent (n=40) of the known territories in the entire Thompson-Fraser population (n=62) occur within a relatively small portion of the populations extent within the BC Hydro Seton-Bridge footprint.

This apparently healthy population, along the Fraser River, is a likely source population for the entire Thompson-Fraser population. Assuming an average reproductive output of 3-4 juveniles/year/pair (average recorded clutch size in BC; pers obs) the annual reproductive capacity of these 40 territories is between ~120-160 young screech-owls fledged each year. This reproductive output likely creates a causal distance-dependent inverse relationship with population density in the Thompson-Fraser population.

Fifteen new Wildlife Habitat Areas (WHAs) are proposed to ensure conservation of screech-owl habitat attributes at all active sites, detected on Crown land, within the project area. Sites detected on First Nations lands, or private land, are recommended for conservation consideration through other management mechanisms.

Fraser River Western Screech-Owl Conservation and Management

Table of Contents Acknowledgements...... 2 Executive Summary ...... 3 Introduction ...... 5 Species Information ...... 5 Subspecies Distribution by Region ...... 6 Subspecies Distribution by Population ...... 6 Goals and Objectives ...... 9

Study Area ...... 9 Methods ...... 11 Call-playback Surveys ...... 11 Daytime Site Assessment ...... 12 Conducting Nest Searches ...... 13

Results ...... 14 Summary of Sites ...... 16 Conservation of Western Screech-Owl Habitat ...... 22

Discussion ...... 22 Management Recommendations ...... 24 Literature Cited ...... 25 Appendices ...... 27 Appendix 1: BC Provincial Western Screech-Owl Database ...... 27 Appendix 2: Survey Data ...... 27

Fraser River Western Screech-Owl Conservation and Management

Introduction Species Information The Western Screech-Owl (Megascops kennicottii) is a small greyish-brown owl with prominent ear-tufts and yellow eyes. Individuals weigh between 100-305 grams, with a body length of 19-25cm and a wingspan of 55-62cm. Within British Columbia, there are two recognized subspecies, the interior M. k. macfarlanei and the coastal M. k. kennicottii. M.k. macfarlanei (hereafter referred to as the interior screech-owl) is restricted to south-central BC, where it is known to breed throughout the Thompson- Nicola, Okanagan, Cariboo and Kootenay Ministry of Environment regions (Hobbs. 2011) (figure 1).

The interior screech-owl is listed as endangered by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC 2002) and is listed on Schedule One of the Canadian federal Species at Risk Act (SARA). In British Columbia (BC), the interior screech-owl is now blue-listed by the (BC) Conservation Data Center (in light of the recent expansion of known range, and number of confirmed territories, the Western Screech Owl was down-listed from “red” to “blue” in 2011) and is recognized as a “Priority 1” under Goal 3 of the BC Conservation Framework (To maintain the diversity of native species and ecosystems). The Western Screech-Owl is also identified by the BC Ministry of Environment (MOE) on the Category of Species at Risk and as a priority species for conservation and management under the Government Actions Regulation (GAR) component of the Forest and Range Practices Act (IWMS-BC MWLAP 2004b). As such, sites detected on Crown land during these surveys are entitled to protection through the designation of Wildlife Habitat Areas (WHAs) which are intended to conserve and maintain habitat values (see Results and Discussion).

In BC, the interior screech-owl has been recorded at elevations between 169 - 1,501m ASL (based on 2012 data as presented by Hobbs. 2013). The species is generally associated with valley bottom deciduous riparian habitats. Western Screech-Owls are secondary cavity nesters, typically using abandoned cavities excavated by Northern Flickers (Colaptes auratus) and Pileated Woodpeckers (Dryocopus pileatus). Nest cavities typically occur in areas dominated by black cottonwood (Populus trichocarpa), trembling aspen (Populus tremuloides), and water birch (Betula occidentalis) (BC MWLAP 2004b). Annual home range sizes in BC (based on telemetric monitoring) have been estimated between 65 ha (Davis and Weir, 2009) and 76.9 ha (Dulisse and Hausleitner, 2011) and juvenile straight-line dispersal distances of 14-38km were reported, with a maximum total (cumulative) dispersal distance of 207 km (Dulisse and Hausleitner, 2010).

Based on extensive personal observations and records submitted by other researchers in BC, breeding typically begins with territorial defense (vocalization), pair bonding and courtship (commencing in March in most areas); followed by copulation, egg-laying and nesting. Pairs incubate for ~30 days and, after hatching, the nestling phase of the life cycle generally lasts another 20-30 days. Typically nesting occurs between April 1st through to June 30th; however, nesting dates appear to be geographically asynchronous across the province. Juveniles typically fledge from the nest sometime in late May or early to mid-June; however, interior screech-owl surveys in the Flathead in 2012 confirmed fledging dates there of July 10-14 (n=2). Clutch sizes between 1-5 young have been recorded in BC. During the post- fledging period the juveniles occupy the nest territory, generally remaining within 500m of the nest tree, while they are tended by the adults. The juveniles begin to vocalize in early July and, as flight capabilities improve, juveniles move increasingly further from the nest as the post fledgling season advances (pers.obs). Juvenile dispersal occurs in early August through September. During this phase both adult and juvenile territorial responsiveness peaks again.

Fraser River Western Screech-Owl Conservation and Management

Subspecies Distribution by Region In BC, data on interior screech-owl detections and territory locations are collected and maintained (by the author) from multiple sources (including volunteer based surveys and formal (funded) inventory, external consultants, government staff and local area naturalists). This database includes information on breeding (status and chronology), population monitoring (sites and detections are recorded), habitat threats, tenure, elevation and conservation status. In total, at the time of writing of this report, there are 821 recorded detections at 349 discrete sites (or territories) of the interior subspecies (NB: the coastal subspecies is tracked and reported separately by the author). Wildlife management regional boundaries have undergone some changes in recent year; however, in order to maintain consistency with the data through the years, this report continues to use the regional names and boundaries used by MWLAP and MoE prior to the creation of MFLNRO. Sites with confirmed use (including breeding) are summarised by region below:  Cariboo (Region 5): Eight sites (2%); the first site was confirmed at Big Bar Creek in July, 2011 (J.Hobbs and F.Iredale. pers obs). In 2012, seven new sites were detected for a total of eight sites confirmed in the Cariboo region. Breeding was confirmed at three of these new sites.  Thompson-Nicola (Region 3): 54 sites (16%); interior screech-owls are rare throughout most of this region; the highest recorded density of occupancy is in riparian habitats surrounding Lillooet. This population was thought to have been extirpated (R.Cannings. Pers.com) until it was rediscovered (J.Hobbs, pers obs) in 2001.  Okanagan (Region 8): 195 sites (57%); the Okanagan and Similkameen valleys are the ‘stronghold’ for the interior screech-owl in BC with the highest recorded number of active sites and breeding records (Hobbs, 2013).  Kootenay (Region 4): 92 sites (26%); the occurrence of interior screech-owls in the Kootenay Region is a relatively recent discovery. More extensive inventories in 2012 resulted in the detection of 30 new sites in the Flathead River drainage (Hobbs, 2013).

The inventories conducted in 2012 represent the first confirmed breeding detections of this species in the Cariboo Region 5 (three sites) and in the Flathead River Valley (three sites) in Region 4. As such, the sites detected in these regions during the 2012 surveys represent a significant range expansion in BC. Furthermore, the detections in the north fork of Flathead River in Canada represent the highest recorded elevation (1,501m) and the first recorded detections in the MSdk4 BEC zone. This recent work has revealed a consistent and strong population distribution pattern in BC. Interior screech-owls are now know to occur in association with all of the major river drainages (east of the Cascades) that intersect the international border and connect the interior subspecies to its core range further south in the United States (US). Subspecies Distribution by Population From a biological perspective it is more meaningful to describe geographically distinct populations (versus management units). In BC, the interior screech-owl occurs in eight distinct populations (Figure 1) east of the Cascades from the international US-Canada border continuing north to Kamloops and up the Fraser River Canyon to Big Bar. West of the Rockies and outside of BC (i.e., in Alberta and Montana), records are uncommon, but there are a two isolated incidental records of the interior screech-owl (Waterton NP).

The northernmost known extent of the interior screech-owl in North America occurs within the Thompson-Fraser population (Figure 1). The Thompson-Fraser population likely constitutes a metapopulation as it is geographically disjunct from the other seven BC populations; however, the

Fraser River Western Screech-Owl Conservation and Management degree of potential for connectivity between this potential metapopulation and the rest of the BC populations is unknown1. All of the other (seven) BC populations occur along the international border and are connected with the species contiguous range in the US.

The eight discrete extant populations of the interior screech-owl in BC are described below (and as shown in Figure 1): 1. The Thompson-Fraser metapopulation occurs east from Chase along the South Thompson River and north to Westsyde along the North Thompson River. The metapopulation continues along Kamloops Lake and the Thompson River to the Thompson/Fraser River confluence at Lytton. The metapopulation also extends for 20 km up Bonaparte Creek and along the Nicola River Valley to Merritt (J. Hobbs, pers. obs). Along the Fraser River, recent records confirm that the metapopulation extends north of Lytton ~180 km to the Big Bar Ferry (J.Hobbs & F.Iredale as described in Hobbs.2011). 2. The Okanagan – Similkameen population extends from the international border at Osoyoos and continues north along the Okanagan valley to Vernon and along the Similkameen River valley to Princeton. It then continues north along Princeton Creek to Aspen Grove. Connectivity between the extant population near Princeton and the known extant population further north near Merritt is feasible. The species has been extirpated from much of its former habitat within urban areas in the Okanagan Valley. North of Vernon screech-owls have been documented to Falkland. Further inventory may better define the potential for connectivity, between Falkland and Chase. 3. The Midway population occurs from Rock Creek westward along the West Kettle River valley to Midway. From Midway, this population extends north for ~80km. It also continues south of Midway (south of the International Border) along the Kettle River. The Kettle River re-enters BC at Grand Forks, connecting the Midway population to the Grand Forks population. 4. The Grand Forks population occurs from Grand Forks northwards up the Granby River to Lynch Creek. This population likely extends east along the East Kettle River where it likely continues north along the Christina Lake valley; further inventory is required to confirm the actual extent of this population. To the south, this population is connected with the core population in the United States (south of the International Border) below Christina Creek along the Kettle River Valley to where it joins the Columbia River. 5. The Trail/Nelson population continues north, from the US-Canada border to Slocan Lake and along Lower Arrow Lake to Edgemont. 6. The Creston population extends from Creston north along Kootenay Lake to Crawford Bay. Connectivity to the Trail/Nelson population may occur along the west arm of Kootenay Lake (west of Crawford Bay), but further inventory is required to confirm this. 7. The Koocanusa population follows the Koocanusa Valley, with occurrences documented in several drainages along both sides of the valley continuing from the international border northwards to Cranbrook. Suitable habitat also continues east along the Elk River to Sparwood however, only one (recent) site has been confirmed near Elkford.

1: There is currently no available data on juvenile dispersal between populations in BC however based on juvenile dispersal studies elsewhere in BC (Hausleitner and Dulisse. 2011) there is potential for connectivity between these areas.

Fraser River Western Screech-Owl Conservation and Management

8. The Flathead population follows the Flathead and Kishinena Rivers north, from their confluence immediately south of the international border, up to a confirmed maximum elevation of 1,501m ASL. This is the highest recorded site in BC. In addition, all sites within the Flathead River population occur in the MSdk4 BEC zone; this is the only area in BC where inventories have been conducted at these elevations or within this BEC zone. The potential for significant range expansions in all other populations (i.e., up to 1500m ASL) is self-evident; however, future inventory is required. The total number of known territories, or sites, within each population is summarized in Table 1.

Table 1: Number of confirmed interior Western Screech Owl territories (sites) in BC Population Name Confirmed Territories Elevation Range (m) BEC Zones Thompson-Fraser 62 169-1,011 BG/PP/IDF Okanagan-Similkameen 186 285-1,150 BG/PP/IDF Midway 6 629-775 IDF Grand Forks 3 538-610 IDF Trail/Nelson 34 414-959 ICH Creston 17 533-987 ICH Koocanusa 8 788-1,194 IDF/PP/MS Flathead 33 1,214-1,501 MS TOTAL 349 169-1,501 5 BEC zones Ttl

Figure 1: Sites with recorded/confirmed interior screech-owl occupancy, in BC, as of March 2013 (n=349). The range of each population is depicted, as labelled. Known sites are depicted as yellow stars.

Fraser River Western Screech-Owl Conservation and Management

Goals and Objectives The objectives of this project are consistent with recommendations as outlined by the provincial Western Screech-Owl macfarlanei Recovery Team (Western Screech-Owl, macfarlanei subspecies Recovery Team 2008). These include:  Survey of suitable habitats to determine current occupancy status and monitor previously detected occupied territories;  Establish Wildlife Habitat Areas on core occupied interior screech-owl territories on Crown land; and,  Identify areas of suitable and capable habitats  Identify core areas for habitat restoration efforts. The information gathered during the surveys will help address knowledge gaps in distribution, population size and demographics of the species in areas previously thought to be unoccupied (and hence, unsurveyed) by the species. The results of this work will be used to guide habitat protection and restoration measures that will assist the province of British Columbia to meet recovery objectives for the Western Screech-Owl macfarlanei (Western Screech-Owl, macfarlanei subspecies Recovery Team 2008).

Study Area The project area is located within the Fraser, Chilcotin, Bridge and Seton River basins, in the rain shadow of the southern coastal mountains (BCRP 2004). The lower elevation potential interior screech-owl habitats within the study area occur within the Interior Douglas-fir (IDF), Ponderosa Pine (PP) and Bunchgrass (BG) bio-geoclimatic zones. Riparian habitats within this area are classified as low and middle bench flood classes (Mackenzie and Moran 2004). The habitats surveyed were consistent with conventional habitat descriptions in BC and consist of cottonwood riparian habitat with an emphasis on elevations below 1,100m within the study area. The town of Lillooet was the epicenter of our project focus (Figure 2).

In total, 94 areas were identified for assessment: 58 areas were within the Thompson-Nicola, (Region 3); 36 were within the Cariboo (Region 5). These areas extended, in geographic scope, along the Fraser River as far south as Lytton and as far north as the Sword Creek bridge at Highway 20. At the northern extent, the areas also included suitable habitat along the Chilcotin River.

Once in the field, on-site assessments were used to evaluate habitat quality within each area identified to develop a refined list of survey areas. Areas with insufficient habitat, or areas that were inaccessible by foot, were eliminated from the list of priority 94 survey areas. Thirteen areas were deemed inaccessible and 19 other areas were eliminated as unsuitable for survey (Appendix 2). The remaining 62 areas (41 in Region 3: 21 in Region 5) were surveyed.

On-site field assessments, within each of the remaining 62 areas identified for survey, were also used to inform efficient, effective and thorough placement of call-playback (CPB) stations to ensure complete acoustic ‘coverage’ of all suitable habitats within each area. These “on site” (field) inspections ensured identification and inclusion of all potential interior screech-owl habitat within the PP, IDF and BG BEC zones within the entire project area.

Fraser River Western Screech-Owl Conservation and Management

Figure 2: Map of the entire project area, showing survey areas (represented by orange triangles) that were initially identified for survey for interior screech-owls in 2012.

Fraser River Western Screech-Owl Conservation and Management

Methods Call-playback Surveys Survey areas were determined using ortho-image based site assessments conducted prior to the survey period. Criteria, including: habitat "patch" size, presence of mature cottonwood and, edge type (‘hard’ versus ‘soft’ edge) were used to assign qualitative ratings to each site prior to survey (Appendix 2). This ‘expert-based’ approach was used to guide and refine survey priorities and ensured efficient survey of all potential/suitable habitats.

Once in the field, each survey area was accessed by road or on foot. Areas selected for survey were prioritized according to site quality and ease of access to optimize survey efficiency and to enable the most effective survey coverage for interior screech-owls within the project area. In order to ensure thorough survey of all suitable habitats, an iPad (Version iii, 64gb) was pre-loaded with ortho-photos of the entire project area prior to fieldwork. The iPad was used as a GIS tablet, using the GIS Roam and GPS Kit applications, to efficiently locate survey areas and to efficiently place call-playback stations during fieldwork. Station placement considered acoustic conditions to ensure thorough and efficient ‘acoustic coverage’ of all identified suitable habitats.

Call-playback surveys followed provincial Resource Inventory Standards Committee (RISC) call-playback standards for nocturnal owls (Hausleitner 2006). Surveys were conducted during the owl’s breeding season and employed a combination of 15 minutes CPB stations placed along a linear transect and/or spot checks to inventory riparian habitats. Linear transects consisted of stations placed approximately 400m apart adjacent to suitable habitats. This method was used in areas where suitable habitat was contiguous. Surveyors drove, or walked, following linear transects from one station to the next. Spot checks were also used in areas where a continuous transect would be impractical or inefficient; these consisted of a single station and were used to inventory smaller, isolated, patches of suitable riparian habitat. During walking surveys, field staff listened while walking between stations to augment total time spent listening. Surveys were not conducted in adverse weather conditions such as steady or heavy rain or wind speeds > 20km/hr (Beaufort 4) (as per RISC protocol).

If an owl was detected (at or between stations) surveyors noted species identification, response times, duration, call type, call rate, direction and distance. This information was used to inform daytime assessments for all interior screech-owls detected. During daytime assessments, surveyors would attempt to ascertain pair status, breeding status and (where applicable) nest location or productivity. Call-playback was ceased if an interior screech-owl or a Barred Owl (Strix varia) was detected. Cessation of call-playback following detection of a Barred Owl ameliorates the risk of predation on any interior screech-owls also attracted to the call. When broadcast was stopped in response to predators, surveyors continued to listen for the remainder of the station time.

In addition, recorded survey data included the start and end time of the survey, time of sunset and the weather conditions at the start and end of each survey. Weather conditions recorded included precipitation, temperature (°C) and wind speed using the Beaufort scale (Appendix 1). Each station location and owl location was recorded using a handheld Garmin Map60Csx GPS unit (units recorded were in UTM format, NAD83 datum).

Fraser River Western Screech-Owl Conservation and Management

Daytime Site Assessment Daytime site assessments were conducted for each area where interior screech-owls were detected. Daytime follow-up surveys (i.e., the day immediately post-detection) were conducted to collect additional information regarding the site status of each occupied territory. Surveyors would attempt to add to known information at each occupied owl territory in the following hierarchical sequence: 1) Sex of owl present: determine sex (based on call pitch). This lowest site status was typically achieved upon first detection, but if call duration is brief and surveyors are less experienced, the follow up survey may be necessary to accurately/confidently determine owl sex. 2) Pair status: determine if the territory is currently occupied by a resident pair. Western Screech- Owls are acoustically sexually dimorphic; females have relatively higher pitched songs compared to males. Unfortunately, female screech-owls are generally secretive and reluctant to vocalize so often go undetected using standard CPB techniques, even when they are present. Often females are only detected during daytime follow-up site assessments, or in many cases remain undetected until their occupancy is given away by the detection of juvenile screech-owls at the site in the post-fledging period. It is a likely assumption that most sites detected via call- playback during the breeding period (April 1-September 30) are paired; however, this assumption may be violated in a declining population (e.g., Spotted Owls). Generally speaking, however, for stable resident owl populations with life-time pair bonding, most territories are typically occupied by pairs. 3) Breeding status: Western Screech-Owls are suspected to be annual breeders in BC (based on extensive personal observations). Nest searches and/or productivity checks were conducted to confirm breeding based on the visual detection of a female owl in a nest cavity or based on presence of juveniles in the territory post-fledging (see section: “Conducting Nest Searches”). 4) Productivity: Daytime and nighttime searches were conducted at active sites to collect data regarding productivity. Young (fledged) owls begin to vocalize readily in response to call- playback surveys by late June, and continue to vocalize until September when they disperse from their natal area. The responsiveness and curiosity exhibited by juveniles (post-fledging) enables easy/efficient detection of young. Productivity checks often yielded successful results even where pair status and/or breeding status (i.e., nest detection) assessments were unsuccessful.

In addition, daytime site assessments facilitate the collection of habitat information. When feasible, follow-up assessments were conducted during daytime or dusk at locations where owls were found to be nesting or roosting. If a daytime (roost) location was not determined at a site, then habitat assessments were conducted proximal to nighttime detection locations.

Site assessments were conducted to collect a general habitat description of the immediate area. Each assessment included an estimate of the extent of riparian habitat at the site (in meters and total hectares), the dominant conifer and deciduous species present, and the age class of the stand. Surveyors also recorded the presence of cavities and suitable nest tree species (black cottonwood), and the presence of any owl sign observed (pellets or white wash).

Occupied interior screech-owl sites were also assessed from a landscape context and habitat threats were noted. Based on these assessments, site-specific recommendations to mitigate threats or improve/conserve habitat for interior screech-owls are also provided.

Fraser River Western Screech-Owl Conservation and Management

Conducting Nest Searches Interior screech-owl nests were found using the following experience-based methods:  Daytime surveys are most effective at dawn or dusk immediately following the nighttime detection (i.e., daytime response rates decline dramatically if the site is not ‘primed’ the night before). Where feasible, daytime searches were conducted at these optimal times.  Response data from preceding nocturnal surveys was interpreted, in the field, to refine and limit the area(s) that needed to be searched during the day. Search priority was assigned first to areas where pairs responded or to areas where agitated (bark) calls were heard. Other calls that were interpreted to indicate the potential nest stand included courtship and mating calls (cooing, copulation or extended trill). If no agitated, courtship or mating calls were heard at a site, then priority (for nest searches) was assigned to areas that had early evening detections (i.e., detection time was close to dusk) or short response times.  During daytime follow-up assessments, specific vocalizations (“Tee-tee do” call) were broadcast (using a FoxPro4 Megaphone). Calls were broadcast at controlled (quiet) volumes to elicit a response from the male (NB: Females will occasionally peer out of next cavities in response to a call, but, unlike most other owl species, Western Screech-Owls rarely show themselves in response to ‘tapping’ the bole of the nest tree structure, so the latter method is discouraged).  Once the owl (either sex) begins to counter-sing, observers approached (quietly) to determine, via visual search, the roost site of the calling owl. Surveyors would move silently (no talking) and discretely when searching for owls in the day; when the owls do respond the vocalization is typically very quiet (audible at a max of 50m). In the daytime, Western Screech-Owls are nervous when calls of conspecifics are heard and are quickly silenced if any other noise is made.  Once a visual detection was acquired, potential nest cavities were inferred from the male owls perch position. Typically the male is found roosting nearby, upslope and facing the nest tree. Care was taken to avoid over-stimulating (via call- playback) the male as he will, if overstimulated, move towards the call source and many important ‘clues’ are lost if the owl has moved from his roost position. For similar reasons, great care was taken to avoid flushing the roosting male as the roost site was approached during searching; again, if flushed then these important clues are lost. When searching for roosting owls, surveyors would pay close attention to owl white-wash and passerine response (mobbing) as these also provide important clues.  Once a roosting male was found all suitable (3” diameter or larger) cavities that were visible from the male’s position in the roost site were searched. Each suitable cavity (including tree- chimney structures) was visually inspected (using binoculars) for presence of cobwebs and flies. Note: active nests will not have cobwebs (over the entrance) and will have flies present (especially as temperatures increase as the nesting phase progresses); flies are often visible flying in/out of the nest entrance.  Once a specific cavity was identified, juvenile begging calls were played, whilst visually watching the cavity, to lure the female from the cavity. If there were several cavities, each cavity would be monitored simultaneously as the females appearance at the cavity entrance is often tentative and brief. If this failed to produce a response (i.e., no visual confirmation), then the suspected nest cavity was observed as the night fell as at this point the female will always exit the cavity to defecate and receive food from the male. On cool nights (temp<10°C) she will return within 20 minutes when young are undeveloped. On warm nights she may stay away for >1hr. These techniques were used effectively and efficiently to determine active interior screech-owl nest locations.

Fraser River Western Screech-Owl Conservation and Management

Results In total, 94 areas were identified for survey - 58 areas were within the Thompson-Nicola (Region 3); 36 were within the Cariboo (Region 5). Survey stations were identified to ensure inclusion of all potential interior screech-owl habitats within the PP, IDF and BG BEC zones encompassed within the study area. Each area was identified based on a visual ortho-photo expert based GIS assessment prior to the commencement of fieldwork (see Methods section).

Of the 94 areas identified for survey, 13 were inaccessible2 and 19 others were eliminated (based upon “on-site” field habitat assessment) as unsuitable for survey (Appendix 2). The remaining 62 areas (41 in Region 3: 21 in Region 5) were surveyed with varying degrees of effort applied to each area, as appropriate depending on the survey result. For instance, if an owl nesting pair was confirmed on the first visit it negated the need for further follow up and, in these cases, only one survey of the area was conducted. In addition, as funding was insufficient to allow three or four survey repetitions for all areas, relative habitat quality (based on field assessments completed during the first repetition) was also used to inform decisions to determine which areas would receive second, third and/or fourth repetitions. Table 2 describes the application of effort for all 62 areas that were surveyed in 2012.

Table 2: Summary of survey areas showing the number of repetitions applied the total number of sites where interior screech-owls (WSOW) were detected, and of these, the number of sites that were new. Site Visit Number of Areas # of sites with WSOW Detected New WSOW sites found First Visit 62 17 10 Second Visit 42 16 9 Third Visit 14 3 0 Fourth Visit 5 5 0

Surveys were conducted in two phases in 2012 to capitalize on peak periods of responsiveness exhibited by interior screech-owls. The first phase began on April 7, 2012 and continued through to June 28, 2012. There is a period of decreased adult responsiveness in July and August so surveys were ceased to avoid expending effort, and project funds, during this relatively dormant phenological period. A second ‘peak’ in owl responsiveness occurs in September (as illustrated by % detection frequency) during the juvenile dispersal phase and we resumed CPB surveys to synchronize with this second ‘peak’. The second phase began on August 23, 2012 and continued through to September 27, 2012.A total of 77 nights of survey were completed in 2012 (both phases) totaling 741 call playback stations with temporal effort described as follows:  April: 20 nights  May: 17 nights  June: 13 nights  August: 7 nights  September: 20 nights On average, 15 minutes of survey was applied at each station representing a total of ~185 hours spent listening for owls. Approximately 50 crew-days of effort was also expended for daytime follow-up site assessments at all active sites to more accurately determine site status, reproductive activity, and reproductive success (see Methods-Daytime Site Assessment & Conducting Nest Searches)

2: The original requested budget allowed for helicopter travel to reach inaccessible areas however reduction in awarded amount required deletion of these 19 areas from our project consideration. These areas are identified for future consideration.

Fraser River Western Screech-Owl Conservation and Management

All owl species detected during surveys were recorded. In total, 120 owls were detected in 2012. Of these 120 owl observations, interior screech-owls were the most commonly detected species ( 53%, n=63). Northern Saw-whet Owls (Aegolius acadicus) were the next most commonly detected species (16%, n = 19) followed by Great Horned Owl (Bubu virginianus) (15%, n=18), Barred Owl (8%, n=9), Long- eared Owl (Asio otus) and Flammulated Owl (Otus flammeolus) (each at 3%, n=4). The Short-eared Owl (Asio flammeus), Northern Pygmy Owl (Glaucidium gnoma) and Boreal Owl (Aegolius funereus) had the lowest detection frequency, with only a single detection of each of these species. The number of detections, by species, is described in Table 3.

Table 3: Detection frequency, by species, for call-playback surveys in 2012. Species # of detections % detected Western Screech-Owl 63 53% Northern Saw-whet Owl 19 16% Great Horned Owl 18 15% Barred Owl 9 8% Long-eared owl 4 3% Flammulated Owl 4 3% Short-eared Owl 1 1% Northern Pygmy Owl 1 1% Boreal Owl 1 1% 120

The first interior screech-owl was detected on April 7, 2012 with the last detection occurring on September 25, 2012. The average response time (RT) for interior screech-owls at survey stations was eight minutes (range 1-40 min; n = 48). RT was not available for all 63 owls detected as this variable is not applicable for owls that were detected calling spontaneously upon arrival. The overall survey success rate was 0.1 interior screech-owl/survey station. These values are consistent with response rates conducted in other areas of the province (J.Hobbs. pers.obs).

Nests were located at five sites including: Cayoosh (same cavity as 2011), Spray, Towinoc, Butcher and Barney. Juveniles were detected, after fledging, at the following seven sites: Cayoosh (n=5), Spray (n=3), Towinoc (n=4), Texcon (n=2), Nesikep (n=2), Indian (n=1) and Hull Arden Creek (n=1).

Occupied sites detected in 2012 were entered into a provincial interior screech-owl database and overlaid, in a GIS environment, with all previously known sites. Detections greater than 1km from any previous interior screech-owl detection were classified as independent occupied (breeding) territories (or sites)3.

Prior to 2012, there were only 21 sites at which interior screech-owls had been documented within the Bridge, Seton, Fraser and Cayoosh watersheds. The 2012 surveys resulted in the detection of 19 new sites; seven new sites in Region 5 (Cariboo) and 12 sites in Region 3 (Thompson-Nicola). There are now a total of 40 confirmed interior screech-owl territories within the Bridge-Seton footprint area. In addition, continued activity and breeding was confirmed at seven sites that were known from previous inventory in the project area.

3: Three sites were detected, with confirmation of simultaneous vocalizations from both males and females (pairs) recorded at all three sites at Towinock Creek, Sexy Texy and Spray Creek. These three territories were spaced only 400m apart; this represents the highest recorded density of occupied/active Western Screech-Owl territories in BC.

Summary of Sites Figure 3 and 4 show the geo-spatial distribution of all sites. Observations at each site are summarized in Table 4.

Figure 3: All sites detected in the study area within the Cariboo Region in 2012, including new sites (n=7) (yellow stars and labels) and previously known sites (n=1) (red circles/blue labels) that were re-confirmed (as occupied) in 2012.

Fraser River Western Screech-Owl Conservation and Management

Figure 4: Sites detected in the study area within the Thompson-Nicola Region in 2012 including new sites (n=12) (yellow stars and labels) and previously known sites (n=6) (red circles/blue labels) that were re-confirmed (as occupied) in 2012 (NB: one new site (Watson Bar) is beyond the map extent and two previously known sites are difficult to make out on the map above as they are close together.).

Fraser River Western Screech-Owl Conservation and Management

Table 4: Summary of interior screech-owl sites observations from 2012 survey. Site Name Date Status Tenure Observation Summary and Site Comments Detected New Sites in 2012 Barney April Nest IR/Park Female observed in nest during second visit in the chimney of a large DBH cottonwood Creek 27/May 7 Found (Ctwd) tree. No information on productivity. Small linear patch of old-growth Ctwd along Barney Creek - habitat extends into Edge Hills Prov. Park. Big Bar September Pair Crown Pair detected, female approached from far away. The habitat at this site is so small, and Ferry 21 detected (WHA so disjunct, that it was suspected that the owls were briefly using this habitat patch Proposed) temporarily and likely reside further upstream on Big Bar Creek. Butcher April Nest Private UTM was projected (first visit) to the bank of the Fraser. During daytime follow-up the Creek 27/May 7 Found nest was detected (May 7) ~150 upstream of the Butcher/Fraser confluence. The nest was located in a cavity in the top 1/3 of a large DBH Ctwd tree. Cavanagh September Pair Provincial A pair of interior screech-owls was detected with strong territorial behavior. Later, on Creek 25 Park the same evening, a suspected juvenile was detected 1.9km further upstream. This was likely a juvenile dispersing (dispersal patterns follow linear riparian corridors). Chuloe- June 5 Male Crown The convergence of two creeks, as they confluence with the Fraser, create a small patch wacku (WHA of Ctwd habitat at this site. Adjacent coniferous forest (soft edge) likely provides ample Proposed) foraging habitat. Della June Male Crown/IR An adult male interior screech-owl was detected twice at this site. Daytime follow-up 3/June 23 (WHA surveys, following both detections, were unsuccessful but it is suspected that the nest Proposed) tree is within 100m of both detection sites. The habitat continues upstream for ~1km and is bordered by adjacent coniferous forests (soft edge). The lower portion of Della Creek is on IR, but the upper portion (at and above the detection site) is on Crown land. Denver August 28 Male Crown Fairly extensive linear patch of suitable habitat near vicinity of calling male. Strongly Creek (WHA territorial; suspect resident pair at this site. Proposed)

Fraser River Western Screech-Owl Conservation and Management

Site Name Date Status Tenure Observation Summary and Site Comments Detected Hull Arden September Pair Crown The linear strip of Ctwd habitat at this territory extends from the mouth of Hull Arden 4 (WHA Creek (at the Fraser confluence) continuing upstream for at least 2km before conifers Proposed) begin to dominate (as valley sides steepen). Indian August 28 Female IR Adult female calling from linear patch of suitable habitat along Indian Creek. Juvenile Creek and found ~630m upstream in an adjacent patch of aspen. Suspect nest site was at the Juvenile female detection location. Izman April 9 / Male Crown Izman Creek supports Ctwd habitat, with coniferous adjacent forest from its confluence April 22 (WHA with the Fraser continuing upstream for 6km. The owl was located ~4km upstream from Proposed) the confluence. It is suspected that the riparian habitat along Izman Creek likely supports at least two breeding pairs of interior screech-owl. A suitable/likely cavity was detected ~50m from the male’s daytime roost but the female couldn't be coaxed to reveal her position. Nesting is strongly suspected at this site. Kelly Creek April Male Crown / Kelly Creek forms the southern edge of Edge Hills Provincial Park. An adult male was 25/June Park detected, on two separate survey nights, using the old-growth cottonwood riparian 23 (WHA habitat along Kelly Creek. There is an excellent (wider/bigger/older) patch ~1km Proposed) upstream that is likely part of this owl's territory. Lee Creek September Male Crown Detected a single male. Excellent habitat - Ctwd mixed with conifers. Likely enough 20 (WHA habitat here for at least two pairs. Proposed) Lillawassun April Male Crown / This linear patch of old-growth Ctwd extends for at least 2km upstream (east-along the 22/Sept 5 Private creek) from the confluence of Lillawassun Creek and the Fraser. An historic record of a (WHA road-killed Western Screech-Owl was recorded here, but the 2012 detection was the Proposed) first confirmation of continued activity at this site. Maria September Female Private An adult female was detected in the Ctwd riparian habitat along the lakeshore of Creek 13 Pavilion Lake. This habitat connects with a much larger patch of Ctwd and aspen that continues north towards the Fraser for ~1km. This is the highest elevation site recorded within the study area and likely represents a key connectivity corridor with the rest of the population further east towards Cache Creek and Kamloops.

Fraser River Western Screech-Owl Conservation and Management

Site Name Date Status Tenure Observation Summary and Site Comments Detected McFreak May Male Crown An adult male was detected on two separate occasions. The owl was using a small, but 6/June 27 (WHA high quality, patch of Ctwd habitat that occurs at the confluence of a small seep and the Proposed) Fraser River. There is ample foraging habitat as the owls territory likely extends into adjacent (soft edge) coniferous habitat along the Fraser River. The understory is very dense at this site making nest searches very challenging. Nekertch June 5 Male Crown / The 1.7km linear strip of Ctwd habitat at Nekertch Creek is typical and likely highly IR productive, habitat for the interior screech-owls at this site. The forest is mixed Ctwd- (WHA conifer with soft edge. The owl detection, and most of the suitable habitat, occurs along Proposed) the lower reaches of the creek (on IR) however ~40% of the habitat along Nekertch Creek occurs upstream of the IR boundary on crown land. Sexy Texy April Pair IR This site is one of three sites (including Sexy Texy, Spray and Towinoc) located in 7/June excellent habitat comprised of a large contiguous patch of old-growth Ctwd, with soft 22/Sept 19 edge, on the west side of the Fraser River at Spray Creek. The habitat patch extends for several kms and has repeated recorded use by interior screech-owls from previous years, including previous records of confirmed breeding. Siwhe August 26 Female Crown / A single adult female responded at this site. The habitat along Siwhe creek is composed IR of a fairly extensive linear strip of Ctwd riparian habitat that continues downstream (WHA along the Fraser at the creek mouth. Adjacent coniferous habitat likely provides ample Proposed) foraging habitat for the owl(s) at this site. Watson Bar May 14 Male Crown Long wide linear corridor of highly suitable interior screech-owl habitat. It is suspected Creek (WHA that there are at least two resident pairs in this area. Proposed)

Fraser River Western Screech-Owl Conservation and Management

Site Name Date Status Tenure Observation Summary and Site Comments Detected Previously Known Sites Big Bar April 15 Male Crown This site was first confirmed (by the author) in 2011; during this visit a single suspected Creek (WHA nest was found (female flew from cavity; juvenile down present on bark of tree). The Proposed) site was detected again in 2012 but only the male was found. Very small patch of nesting habitat connected to badly degraded habitat extending upstream along creek. Cayoosh May, June, Pair & 5 Crown/priv Breeding was again confirmed at this site in the same cavity used in 2011 (cavity in live Creek July, Aug juveniles ate (WHA) Ponderosa Pine on bluff). The post-fledging area within the campground was used again in 2012. There were five juveniles (and both adults) present through July and August. McPhee September Male Crown/priv The Ctwd owl habitat at this site is constrained to a linear corridor that follows McPhee Creek 19 ate (WHA Creek and ends at the Fraser confluence. The owls appear to mainly be using the lower Proposed) reaches of habitat on private land, but the territory also extends upstream onto Crown land. Nesikep May Male, Crown The nest site has not been located at this site but the adults and juveniles have Creek 6/June 22 Female (WHA) repeatedly been detected along the road edge ~160m upslope from the banks of the and 2 Fraser. The owls are suspected to be nesting in a small patch of Ctwd habitat on the juveniles bank of the Fraser, immediately below the detection site. The area was first found in 2003 and has eight detections in total, including three records of breeding confirmation (2005, 2008 & 2012). This site is currently being managed within a WHA. Spray Creek April 8/ Pair and Private This site is one of three sites (including Sexy Texy, Spray and Towinoc) located in April juveniles excellent habitat comprised of a large contiguous patch of old-growth Ctwd, with soft 9/June 22 (# edge, on the west side of the Fraser River at Spray Creek. The habitat patch extends for unknown several kms and has repeated recorded use by interior screech-owls from previous ) years, including previous records of confirmed breeding. Texas April Pair & 2 Private Excellent patch of mature Ctwd that extends linearly along the Fraser for several kms. Confluence 7/June 22 juveniles Towinoc April Pair and Private This site is one of three sites (including Sexy Texy, Spray and Towinoc) located in Creek 8/June 4 excellent habitat comprised of a large contiguous patch of old-growth Ctwd, with soft 22/August juveniles edge, on the west side of the Fraser River at Spray Creek. The habitat patch extends for 23 several kms and has repeated recorded use by interior screech-owls from previous years, including previous records of confirmed breeding.

Conservation of Western Screech-Owl Habitat Habitat conservation will be achieved, in a regulatory framework, through the establishment of WHAs at all occupied interior screech-owl sites found on Crown land: this is currently the only legal mechanism available for conservation of Western Screech-Owl habitat and is therefore a key component towards Goal Two of the Western Screech-Owl Recovery Plan (WSOW-RT2008).

Western Screech-Owl habitat (on Crown land) will be managed under the Forest and Range Practices Act as Wildlife Habitat Areas (WHAs). A total of fifteen new WHAs are proposed to accommodate all active interior screech-owl territories detected in 2012 that occur (in part or completely) on Crown land (Table 4-red font). In total, these areas include approximately 1,200 ha of riparian and upland habitat in the Fraser River drainage.

In addition, survey information was submitted to the Species Inventory database (SPI) and occupied occurrence information was submitted to the Conservation Data Center (BC-CDC) to promote improved understanding of the species distribution and ecology in BC.

Discussion The surveys described in this report; including both formal (funded) and opportunistic surveys, represent the first survey for the blue-listed Macfarlane’s (interior) Western Screech-Owl in the Cariboo (Region 5) in BC. These surveys have confirmed the presence of the species in the area (now confirmed at eight sites with breeding confirmed at three of these sites).

Figure 5: All confirmed interior screech-owl sites, within the Thompson-Fraser metapopulation, are indicated by yellow dots. Regional boundaries are indicated by red-dashed lines.

Fraser River Western Screech-Owl Conservation and Management

Nocturnal call-playback surveys can be used to assess presence of some owl species; however, results should be interpreted cautiously as survey efficacy (i.e., ability to detect all owls present in the survey area) is limited by individual owl and species-specific response rates, observer skill/bias, acoustic conditions (e.g., weather/wind/running water/traffic), time of year and time of day, suppression due to presence of predators, and proximity to owl. Increased repetition results in an increased confidence of detection; however, detection certainty is never absolute - owls that are present can often still go undetected even after multiple repetitions. Despite the limitation of this methodology, it still provides a very cost-efficient method for surveying these otherwise cryptic species; the use of this method for this project yielded valuable results and interesting points of knowledge.

The addition of 19 new territories, discovered during the 2012 surveys along the Fraser River, raises the current total number of known interior screech-owl sites in the Thompson-Fraser population up to 62 confirmed sites (when combined with 2012 and previous surveys for the population (including both Region 3 and in Region 5). Within this population, the 40 currently confirmed sites within the BC Hydro Seton-Bridge footprint represent 65% of the known territories in the entire Thompson-Fraser population (Figure 5). Assuming an average reproductive output of 3-4 juveniles/year/pair (average recorded clutch size in BC; pers obs) the annual productivity rate from these 40 territories is between ~120-160 young fledged each year. This reproductive output likely creates a causal distance-dependent inverse relationship with population density in the Thompson-Fraser population. As distance increases, away from this high-density (source) area, there is an obvious observed decline in the known population density (Figure 5).

The results of the 2012 surveys also suggest that the population of owls that occur along the relatively pristine portion of the study area along the Fraser River likely represent near-historic densities for this species in the area. By contrast, the impacted (previously flooded by hydro impoundments) areas along Seton and Carpenter Lakes appear to have relatively depressed populations (relative to likely historic population levels that still occur along the Fraser). The associated loss of low-elevation riparian habitat along creek-lake confluence areas are a reasonable causal explanation.

This project has greatly expanded our understanding of the distribution and abundance of this blue- listed subspecies within BC. As a result of cumulative efforts (previous BCRP surveys in 2006 and 2010), our understanding of the current distribution, abundance and productivity of interior screech-owls within the Bridge-Seton footprint area is significantly more comprehensive than other areas within the species’ range in BC.

In conclusion, further study is required to refine our estimate of population size, dispersal patterns and distribution. More detailed monitoring is also required to refine our understanding of population vital rates including: rate of population change, adult/juvenile survivorship, productivity/fecundity and long- term viability of this population. This approach is recommended as the Western Screech-Owls found within the Bridge-Seton area represent the northern-most extant population of the species in Canada, and the owls in this area are a likely source population for the entire Thompson-Fraser population.

Fraser River Western Screech-Owl Conservation and Management

Management Recommendations The Western Screech-Owl macfarlanei recovery plan recommends the conservation of interior screech- owl nest sites, through stewardship and habitat procurement, as an urgent action item towards reaching the recovery goal of maintaining a viable, well-distributed population of interior screech-owls within the known range of the subspecies in British Columbia (WSOW-RT 2008). At the landscape level, efforts to maintain and conserve occupied habitat and to promote enhancement and conservation of suitable habitats should be made. At the local level, assessment of occupied interior screech-owl sites facilitates conservation through stewardship actions on private land or designation of WHAs on Crown land. The following future recommended actions are proposed:  Continued population monitoring is a vital component of assessing population health, productivity and trend. This important work should be continued for this population in future years.  Insufficient funds prevented access to some areas (we were not able to hire a helicopter to assist with access of several areas as the granted allocation was reduced from the amount requested in the proposal). Sites that were not able to be accessed in 2012 should be surveyed in the future.  Habitat on private conservation lands should be managed through directed management as per stewardship agreements.  St’at’imc Government Services should ensure all interior screech-owl habitats within their authority, and on their territory, should be conservatively managed for the owls. Specific issues that warrant attention include over-grazing (resulting in reduction of shrub layer) and clearing.  WHAs should be established for all 15 confirmed (this project) interior screech-owl territories that occur, in part or in full, on provincial Crown land (see Results).

©Ian Routley

Fraser River Western Screech-Owl Conservation and Management

Literature Cited

BC Conservation Framework. 2009. http://www.env.gov.bc.ca/conservationframework /index.html (accessed Dec 18, 2012).

BC Hydro Bridge Coastal Fish & Wildlife Restoration Program. 2010. http://www.bchydro.com/bcrp/about/index.html

BC Ministry of Water, Land and Air Protection. 2004a. Appendix 5 in Accounts and Measures for Managing Identified Wildlife – Accounts V. 2004. B.C. Ministry of Water, Land and Air Protection, Victoria, B.C. Available: http://www.env.gov.bc.ca/wld/frpa/iwms/ procedures.html (accessed April 15, 2010).

BC Ministry of Water, Land and Air Protection. 2004b. “Interior” Western Screech-Owl (Otus kennicottii macfarlanei) in Accounts and Measures for Managing Identified Wildlife – Accounts V. 2004. B.C. Ministry of Water, Land and Air Protection, Victoria, B.C. Available: http://www.env.gov.bc.ca/wld/frpa/iwms/accounts.html (accessed April 15, 2010).

Cannings, R. J., and T. Angell. 2001. Western Screech-Owl (Otus kennicottii). In The Birds of North America, No. 597 (A. Poole and F. Gill, eds.). The Birds of North America, Inc.,Philadelphia, Pennsylvania, USA

COSEWIC 2002. COSEWIC assessment and update status report on the Western Screech-owl otus kennicottii in Canada. Committee on the Status of Endangered Wildlife in Canada. Ottawa. 31 pp.

Davis, H., and R. Wier. 2008. Western Screech-Owl Conservation along the Shuswap River. Submitted to the Bridge Coastal Restoration Program. Project #05W.Sh.01 97pp

Hausleitner. D and J. Dulisse. 2011. Movement and Habitat Use of Western Screech-Owls in the West Kootenay Region. 2010-11 Field Season Report. Prepared for the Fish and Wildlife Compensation Program and the Columbia Basin Trust. 26pp.

Hausleitner, D. 2006. Inventory Methods for Owl Surveys. Standards for Components of British Columbia’s Biodiversity No.42. Prepared for Ecosystems Branch of the Ministry of Environment for the Resources Information Standards Committee. Victoria, B.C. 52pp

Owls. Submitted to the Bridge Coastal Restoration Program. Project # 05.W.Br.04

Hobbs, J. 2012. Western Screech-Owl Conservation and Management in the Flathead River Basin (2011 Surveys-Final Report). March 1, 2012. p. 1-23.

Hobbs, J. 2013. Western Screech-Owl Conservation and Management in the Flathead River Basin (2012 Surveys-Final Report). March 12, 2013.

Hobbs, J. 2013. Western Screech-Owl Conservation and Management in the Thompson & Okanagan Regions (2012 Surveys-Final Report). March 11, 2013.

Fraser River Western Screech-Owl Conservation and Management

Integrated Land and Resource Registry 2010. Government of British Columbia Crown Registry and Geographic Base Branch. http://archive.ilmb.gov.bc.ca/ilrr/ (accessed June 17, 2010).

MacKenzie, W.H. and J.R. Moran. 2004. Wetlands of British Columbia: a guide to identification. Res. Br., B.C. Min. For., Victoria, B.C. Land Manage. Handbook No.52.

Tripp, T.M. 2004. The use of bioacoustics for population monitoring of the Western Screech-Owl (Megascops kennicottii), Thesis, University of Northern British Columbia, Prince George, British Columbia, Canada.

WSOW-RT. 2008. Western Screech-Owl, macfarlanei subspecies Recovery Team. 2008. Recovery strategy for the Western Screech-Owl, macfarlanei subspecies (Megascops kennicottii macfarlanei) in British Columbia. Prepared for the B.C. Ministry of Environment, Victoria, BC. 14 pp. http://www.env.gov.bc.ca/wld/documents/recovery/rcvrystrat/w_screech_owl_rcvry_strat13020 8.pdf

Young, V.D., J. Mylmymok, J.Hobbs and F.Iredale. 2011. Western Screech-Owl Conservation and Management for the Bridge River Restoration Area. Prepared for: BC Hydro Fish and Wildlife Compensation Program-Bridge Coastal. 55pp http://a100.gov.bc.ca/pub/siwe/details.do;jsessionid=fda21758ce2b896b9cf2e18956eeaacb2b91 6f1e881075e0bfad32c5e2186d35.e3uMah8KbhmLe34MaxyNaxmTaxz0n6jAmljGr5XDqQLvpAe?id =4618

Fraser River Western Screech-Owl Conservation and Management

Appendices Appendix 1: BC Provincial Western Screech-Owl Database Available separately (MS Excel)

Appendix 2: Survey Data Available separately (MS Excel)