YEARS 9 AND 10 OF A LONG-TERM MONITORING EFFORT AT A NEST IN NORTHERN

Richard T. Golightly and Stephanie R. Schneider

Department of Wildlife Humboldt State University Arcata, California 95521

FINAL REPORT February 2011

Years 9 and 10 of a Long-term Monitoring Effort at a Marbled Murrelet Nest in Northern California

Agreement # P0880019

Between the Humboldt State Sponsored Programs Foundation and the California Department of Fish and Game and in cooperation with the National Park Service

Submitted by

Richard T. Golightly Department of Wildlife Humboldt State University Arcata, California 95521

Prepared by

Richard T. Golightly and Stephanie R. Schneider February 2011 ABSTRACT

Marbled Murrelets ( marmoratus) have been endangered in the state of California since 1992 and continue to decline across their range. In recent years this has been primarily due to predation of and young at the nest. Very few studies of murrelets have occurred at their nest due to the difficulty of locating and observing active nests. In northern California, a video camera was installed at one nest site in 2001 and each nesting attempt has been subsequently recorded. Additionally, in 2009 and 2010 a microphone was installed at the site as well. Herein, the 2009 and 2010 nesting seasons are reported for this nest site. In 2009, a nest was not detected at or near the monitored site. However, a murrelet landed at the monitored site and a leg-band was observed on the ’s right leg. Additionally, a Steller’s Jay landed at the site on 5 separate occasions and a Gray Jay landed at the site once. In 2010, a nest was initiated outside the view of the camera on approximately 3 June, the hatched approximately 27 days later on 30 June. The chick was predated on 30 June by at least one Gray Jay. Following the predation of the chick, murrelets were recorded by the camera on 3 separate days before 06:00 (PDT). A pair of Steller’s Jays landed at the site on 6 July in 2010. Murrelets have initiated a nest on this branch during 7 of 10 years. Considering the 7 nesting attempts at this site, the nest has failed 71.4% of the time and each failure has been caused by predation. Finally, at least one member of this breeding pair was a minimum of 10-12 years old.

The Marbled Murrelet (Brachyramphus marmoratus) is a small in the family Alcidae whose populations have declined over the last 30-50 years due to anthropogenic causes, including oil spills (Carter and Kuletz 1995), gill net fishing (Carter et al. 1995), and particularly the loss and fragmentation of nesting resulting from the harvest of old-growth coniferous (Carter and Erickson 1992, Rodway et al. 1992, Kelson et al. 1995, Perry 1995). In 1992 the Marbled Murrelet (hereafter murrelet) was state-listed as endangered in California (California Fish and Game Commission 1992). Also in 1992, murrelets were federally-listed as threatened in Washington, Oregon and California (USFWS 1992). Recent studies have shown that murrelets in California continue to decline (Burger 2002, Strong 2003, Miller et al. 2006, Falxa et al. 2009, USFWS 2009). Further, near shore surveys conducted during summer 2008 at the southern extent of their range failed to detect juvenile murrelets for the first time, signifying a major contraction of the population (Peery et al. 2008, Peery et al. 2009). All large tracts of remaining murrelet habitat in California have been protected since the listing of the murrelet in 1992 (McShane et al. 2004, USFWS 2009). This continued decline has been attributed to nest failure and, more specifically, predation on eggs and young (Peery et al. 2004b, Hébert and Golightly 2006, Golightly and Schneider 2009, Peery and Henry 2010). Murrelet nesting ecology and biology remain poorly described. This is because murrelets fly to nests during twilight hours (Nelson and Hammer 1995a), and nest in the upper canopy of old-growth (Nelson and Hamer 1995b, Jordan and Hughes 1995, Manley and Kelson 1995, Naslund et al. 1995, Golightly et al. 2008). Further, their plumage, nest-site, and breeding behaviors are cryptic (Carter and Stein 1995, Nelson and Hammer 1995a). Consequently, nests are rarely found and, once found, remain nearly impossible for investigators to observe through the entire breeding season (Hébert and Golightly 2006). In fact, only 39 murrelet nests have been exactly located in California (G. Falxa 2010, pers. comm.) since discovering that murrelets nest in trees in 1961 (Kuzyakin 1963, Binford et al. 1975). Since 2001, one nest in northern California has been observed each nesting season using remote video. This long-term video monitoring has provided an opportunity to document multiple years of nest failure, annual patterns of nest initiation, as well as speculation about longevity and nest-site fidelity. Herein observations from the 2009 and 2010 breeding seasons are described. Previous years have been reported elsewhere (2001-2005, Hébert and Golightly 2006; 2006-2007, Hébert and Golightly 2007; 2008, Golighty and Schneider 2009). METHODS This study was conducted at Redwood National and State Parks (hereafter RNSP) in Humboldt County, California. RNSP is one of the largest remaining areas of suitable breeding habitat remaining in California (Ralph et al. 1995, McShane et al. 2004, Hébert and Golightly 2006, USFWS 2009, Golightly and Gabriel 2009). In California, murrelets generally nest in stands of old-growth Redwood (), a habitat type unique to this southernmost extent of their range (Miller and Ralph 1995, Stauffer et al. 2004). In 2001, during a larger effort to find murrelet nests using radio telemetry, the female bird occupying this nest-site was fitted with a radio transmitter and her right leg was banded with a metal U.S. Fish and Wildlife Service band (Hébert and Golightly 2006). Using telemetry, the nest-site was exactly located in 2001 within RNSP. The nest-tree, referred to as the Davison Tree, was an old-growth Redwood located 3.2 km inland from the ocean. The nest-site was located 65.7 m above the ground on a limb that had a 36 cm diameter. Vegetation surrounding this nest-site was predominantly Redwood leaves originating from the nest-branch and epiphytic leather-leaf ferns (Polypodium scouleri; Whitmore and Smith 1993).

1 In 2002, the tree was rigged for climbing and a video camera was installed at the nest- site. Each year following, this specific nest has been monitored using video during the breeding season (mid-March to mid-September; Nelson and Hamer 1995b). To observe the breeding pair in 2009 and 2010, a persistent, waterproof, varifocal zoom video camera (Model KPC- VF325NH, DSP Color CCD Camera, KT & C Co., Los Angeles, CA) was placed approximately 40 cm from the nest, on the upper side of the nest branch. A weatherproof microphone (Model SM1-WP, Electronic Technical Services Inc., Albuquerque, NM) was mounted to the side of the nest-branch and was placed within a few centimeters of previously documented nest-sites. A camouflaged cable wrapped around the tree and lead down to the ground where digital video of all daylight hours was recorded onto an external hard drive. Power was supplied using two Absorbed Glass Mat batteries (Model AGM8A27, East Penn Mfg. Company, Lyons, PA) which were replaced every 3 days. On the ground, computer equipment to manage data storage was cached in a weather-resistant structure 25 m from the base of the tree (Figure 1). Hard drives were exchanged for data retrieval every 3 days. The camera was programmed to record 1 hr video files beginning slightly prior to sunrise (04:58 PDT) and ending after sunset (21:00 PDT). Observers reviewed videos up to 8 times (8x) faster than normal playback speed, making it possible to completely process 1 hr of video in less than an hour. However, all video recorded between 0459 and 0559 was reviewed at the recorded speed with audio on to identify avian species in the vicinity of the nest tree each morning. If nesting was not detected, all video between 0600 and 0859 was reviewed at 8x speed to observe any visits to the nest tree by murrelets or other avian species (video was not reviewed after 0859 because nest initiation was not expected after this time; pers. obs. R. Golightly). If a murrelet, or other avian species, was observed at the nest-site, video playback speed was reduced to normal speed for the entire video file (1 hr) so that both video and audio could be reviewed. For 2010 only, all vocalizations by Steller’s Jay (Cyanositta stelleri), Gray Jay (Perisoreus canadensis), Common Raven (Corvus corax), and American Crow (Corvus brachyrhynchos) audible 15 min before and 15 min after sunrise were counted each morning that audio was recorded between 3 May and 13 July. Vocalizations were used to calculate a daily vocalization index for each species audible. This was accomplished by dividing the half-hour surrounding sunrise into 30 1-min intervals. For each 1-min interval, a species was either present (if any vocalization was heard) or absent (if no vocalization was heard). Then a species-specific index of vocalizations was calculated based on the proportion of 1-min intervals that calls were detected each morning sampled. RESULTS In 2009, recording began on 11 May and ended on 15 July, a span of 65 days. The monitoring system successfully recorded audio and video each day in 2009. In total, 852 hours were recorded and 452 hours were subsequently reviewed during 2009. In 2010, recording began on 3 May and ended on 17 August, a span of 107 days. During these 107 days, 30 days were not recorded due to technical failures with the monitoring system (Figure 2). In total, 984 hours were recorded and 204 hours were subsequently reviewed during 2010. 2009 Nesting Season In 2009 evidence of nesting at, or near, this site was not detected. Although nesting was not documented in 2009, a banded murrelet was observed visiting the site on 17 June at 05:45. The visit lasted 51 sec. On this single visit the murrelet gave a whistle call (Nelson 1997) as it landed on the nest-branch. The murrelet then assumed incubatory posture in the exact location of the 2008 nest-site (Figure 3). The band on the bird’s right leg was visible as it departed from the

2 branch. In addition to this single visit, the microphone detected murrelet keer calls (Nelson 1997) in the vicinity of the Davison Tree on each of the 65 days monitored. Avian species considered potential predators of murrelets were also detected, both visually and auditorially, near the Davison Tree during 2009. Steller’s Jays (Cyanocitta stelleri) were seen at the nest-site on five separate occasions: 12 May (8 sec visit), 13 May (10 sec visit), 23 May (8 sec visit), 6 June (12 sec visit), and 17 June (9 sec visit). Steller’s Jay calls were also recorded by the microphone on 91% of the days monitored. Additionally, a Gray Jay landed at the monitored site on 1 June (10 sec visit). Common Ravens (Corvus corax) were not seen, but were detected by the microphone on 17% of all days monitored. Additionally, Barred Owls (Strix varia) and Red-shouldered Hawks (Buteo lineatus) were each audible on one day in 2009. Avian species not considered potential predators of murrelets or murrelet nests were also detected in 2009. A Golden-crowned Kinglet (Regulus satrapa), Allen’s Hummingbird (Selasphorus sasin), and Chestnut-backed Chickadee (Poecile rufescens) were recorded at the nest-site by the camera. 2010 Nesting Season In 2010, nesting was not documented by the camera at the site. However, there was evidence that an egg was laid beyond the camera’s field of view. Based on audio recorded by the monitoring system (wing beats, landings, chick-calls) and circumstantial evidence (tree climbs, audio-visual survey), the egg was laid on or immediately following 3 June. Then, on 30 June, the egg hatched and shortly thereafter the chick was predated. In 2010, murrelet activities (wing beats, landings) at the Davison Tree were much more numerous than in 2009. Wing beats of murrelets flying in the immediate vicinity of the Davison Tree were detected on 40% days (n=77days) where audio was recorded (Figure 2). Additionally, murrelet landings into the Davison Tree were detected on 11.7% days (n=77days) where audio was recorded (Figure 2). Although murrelets were heard flying near the tree and landing in the tree frequently in 2010, that alone did not constitute sufficient evidence to conclude that a nest was initiated in the Davison Tree. The conclusion that nesting and subsequent predation occurred was corroborated by observations made during 3 separate cases where the tree was climbed by a biologist (20 May, 3 June, and 30 June; Figure 2). Additionally, an audio-visual (AV) survey from the ground on 28 June and audio recorded on 30 June by the monitoring system (Figure 2) established specific evidence of nesting and subsequent predation. On 20 May and 3 June, a climber ascended the tree to repair the camera system and an active murrelet nest was not observed. On the 28 of June, an AV survey from the ground was conducted by 3 observers because of suspicion, based on audio evidence, that a nest had been initiated beyond the camera’s view. During the AV survey, a murrelet was observed entering the canopy of the Davison Tree near the historic nest-site at 05:31 (PDT) from the northwest. Then, at 05:35 a murrelet was seen exiting the Davison Tree at approximately the same level of the canopy in a southwest direction. This observation appeared to be an incubation exchange (the daily alternation of adults incubating the egg at the nest). Therefore, on 30 June a climber ascended the Davison Tree around 10:00 to search for an active nest and reposition the camera if a nest was located. Neither a nest nor a fecal ring was located, despite the climber’s inspection. However, the climber noticed that the landing platform used by murrelets at the monitored site in previous years was clearly worn by recent and repeated landings (corroborating the sound of landings in the audio recordings). Additionally, the climber discovered a loose clump of downy

3 feathers (Figure 4), presumably from a very young murrelet, approximately 2 m distant from the 2008 nest-site (Figure 3). Following this final ascent, audio recorded on 30 June was reviewed. Between 06:00:20 and 06:07:10 the audio recorded suggested that a murrelet chick was predated by at least one Gray Jay (Table 1). There were a substantial number of murrelet calls (both adult and chick), as well as Gray Jay calls, near the microphone between 06:01:09 and 06:03:33. At 06:03:33 the calls of the murrelet chick became more distant from the microphone, and subsequent calls from the chick were not heard. At 06:03:50, Gray Jay calls were heard, but also farther from the microphone. Between 06:04:32 and 06:04:35, wing beats of an adult murrelet were audible near the microphone. For the next minute, neither murrelets nor Gray Jays were heard. Between 06:06:04 and 06:07:07, Gray Jays were audible at a distance again. After this, Gray Jays were not heard. Wing beats of an adult murrelet were again audible near the microphone at 06:22:24, 06:31:49, and 06:44:55. Video and audio recorded between 07:00:00 and 10:59:56 was reviewed, but no additional sound from murrelets or Gray Jays was heard. After the alleged nest predation on 30 June, adult murrelets were recorded by the camera on 3 separate occasions (Figure 2). On 8 June, 1 murrelet was seen moving in the leather-leaf ferns adjacent to the 2008 nest-site starting at 05:38:14 and lasting for 37 sec. Then, on 19 June, 2 murrelets were present in the leather-leaf ferns between 05:40:38 and 5:47:51. Neither arrival nor departure was witnessed. Both murrelets were seen departing from the branch together at 05:47:51. Finally, on 24 July, a murrelet was seen departing the branch at 05:44:28. Arrival of this murrelet was not observed on 24 July because it occurred beyond the camera’s field of view. Avian species considered potential predators of murrelets (corvids and raptors) were detected, both visually and auditorially, during 2010. A pair of Steller’s Jay were seen at the nest-site on 6 July (25 sec). No other observations of corvid or raptor species occurred during 2010. Corvid species that were recorded by the microphone in 2010 included Steller’s Jay, Common Raven, and Gray Jay (Figure 5). Steller’s Jay calls were heard on 94.0% of the 50 days sampled. Furthermore, Steller’s Jay calls were detected in 17.6 ± 1.2% (x¯ ± SE) of the 1-min intervals each day. Common Raven calls were heard on 30.0% of the 50 days sampled and their calls were detected in 1.9 ± 0.5% of the 1-min intervals each day. Finally, Gray Jay calls were heard on 22.0% of the 50 days sampled and their calls were detected in 1.7 ± 0.5% of the 1-min intervals each day. For raptor species, only Barred Owls were audible (on 13% of the 77 days recorded). Avian species not considered potential predators of murrelets or murrelet nests landed at the monitored site. These species included Swainson’s Thrush (Catharus ustulatus), Brown Creeper (Certhia americana), and Pacific Wren (Troglodytes pacificus). DISCUSSION Nest Failure The murrelets using the nest monitored by this study have had an average reproductive success of 20%, fledging chicks in 2 of 10 years (2001, 2003; Table 2). In three years (2006, 2007, 2009) no egg-laying occurred or was able to be identified, so the actual productivity at the nest could be as high as 29% (2 of 6 possible attempts). For the five remaining years (2002, 2004, 2005, 2008, 2010), the nest failed as a result of predation. Murrelets have evolved with predation, as evidenced by their cryptic morphology and elusive nesting habits. At present, nest predation is currently the most common fatality for murrelet eggs and chicks, so prevalent that it prohibits successful recovery of the population (McShane et al. 2004, Golightly and Gabriel 2009, Peery and Henry 2010, USFWS 2009). Historically, nest predation could not have

4 compromised murrelets to the same degree, or this species would have gone extinct long ago. Unfortunately, this may no longer be the case and conditions under which murrelets have evolved and avoided predation have probably changed. For example, murrelets are predisposed to nesting along canopy gaps, preferably along waterways, which facilitate access to their nest- site (Nelson 1997, Manley 1999, Burger and Bahn 2004, Zharikov et al. 2006). In recent times, many of the edges that murrelets used for nesting have transitioned from natural to artificial edges (Marzluff and Neatherlin 2006). Conversely, various corvid species (Steller’s Jay, Gray Jay, and Common Ravens) have increased in density along anthropogenic edges because these edges often co-occur with supplemental foods from fruiting shrubs and anthropogenic sources (Marzluff and Restani 1999, Henske et al. 2001, Raphael et al. 2002, Ibarzabal and Desrochers 2004, Zharikov et al. 2006, Malt and Lank 2009). This spatial overlap of nesting murrelets with denser predator populations has created a situation where predation risk at murrelet nests has increased markedly. During a multiple-year radio telemetry study of murrelets nesting in RNSP, Hébert and Golightly (2006) calculated annual nest success rates as low as 3.1% and as high as 9.2%; most failures were ascribed to predation. In the Santa Cruz Mountains, nest failure due to predation was estimated to be about 81% (Peery et al. 2004b). The 2010 predation was the first loss in the chick stage for this nest. All previous nest failures at this site occurred during the egg stage. However, during their radio telemetry investigation Hébert and Golightly (2006) also showed that chicks are lost to predation, but to a lesser degree than eggs. At the Davison Tree, for both nesting attempts where the egg successfully hatched, the resulting chick survived to fledge. This was true even for the chick in 2003 that was approached within 0.5 m by a Steller’s Jay at 1-2 weeks post-hatching (the range resulting from uncertainty about the exact day of hatch due to equipment failure surrounding the day of hatch; Hébert and Golightly 2007). It is possible that for a few days following hatching, murrelets are still extremely vulnerable to predation until they can defend themselves from jays. While Gray Jays are generally known to predate bird eggs (Bent 1946, Ouellet 1970, Strickland and Ouellet 1993), it’s possible that this species poses a greater risk to murrelet chicks than other corvids because of their biology and food acquisition habits. Gray Jays, unlike other corvids in the Pacific Northwest, travel through the in family groups of 3-4 individuals after their young have fledged (Strickland 1991, Waite 1991, Strickland and Ouellet 1993). Gray Jays initiate nests and fledge young relatively early in the season, which results in these family groups beginning to travel through the forest together between mid-May to mid-June (Strickland and Ouellet 1993); this timing coincides with when murrelet eggs also begin to hatch (Hamer and Nelson 1995, Hébert and Golightly 2006). Gray Jay family groups spend a majority of their time foraging along the forest edge, coincidental with where murrelets typically nest (Nelson 1997, Manley 1999, Burger and Bahn 2004, Zharikov et al. 2006). Traveling in a group, rather than individually, we speculate that Gray Jays could be more capable at locating a young murrelet compared to a single Steller’s Jay since there are more individuals available to discover the nest. Once discovering the nest, an adult Gray Jay (60-82 g; Strickland and Ouellet 1993, Rogers 2005) would be able to carry a newly-hatched murrelet away from its nest. This is because a murrelet chick weighs between 36-96 g (Sealy 1975, Binford et al. 1975) and Gray Jays are able to fly with loads weighing as much as 64% their own body weight while using their feet to hold the load (Rogers 2005). The predation at the Davison Tree in 2010 represents the first documentation of a Gray Jay predating a murrelet nest. Prior to 2010, two species of corvid had been unequivocally identified as the cause of nest failure at this nest: Steller’s Jay and Common Raven (Table 2). In

5 2005, predation occurred prior to civil dawn (the point which the camera can detect light); as a result, the predatory species could not be identified. Although Gray Jays have never been observed predating a murrelet nest, researchers have recognized the potential for this species to cause nest failure for murrelets (Nelson and Hamer 1995, Burger 1995, Burger 2002). This is because Gray Jays are known to feed on the eggs and young of a variety of avian species (Ouellet 1970, Strickland and Ouellet 1993, Gutzwiller et al. 2002) and they occur in habitat dominated by coniferous forest (Strickland and Ouellet 1993). Humboldt County is at the southwestern extent of the Gray Jay range, and this species has been generally described as uncommon in this county (Harris 1996, Hunter et al. 2005). However, Gray Jays can be attracted to areas of the forest where anthropogenic food is available, such as in national and state parks (Gutzwiller et al. 2002, Hunter et al. 2005). The 10 years of observation at the Davison Tree enhance existing knowledge of murrelet nest predation. This single site provides 4 of 6 (66.7%) nest-predator identifications range-wide that do not depend on inference or assumption. Apart from our study, the literature only cites two additional instances for which nest predators have been identified at non-artificial murrelet nests; one Steller’s Jay and one Common Raven (Singer et al. 1991, Nelson and Hamer 1995a, McShane et al. 2004). Many additional avian and mammalian species have been implicated as potential nest predators, but specific evidence at this time does not exist to support contribution by other nest predators (McShane et al. 2004, USFWS 2009). Nests have also failed following the predation of a breeding adult, either near the nest or when the adult is in transit to the nest (Marks and Naslund 1994, pers. obs. R. Golightly). Species unequivocally identified killing an adult murrelet include Sharp-shinned Hawk (Accipiter striatus; Marks and Naslund 1994), Peregrine Falcon (Falco peregrinus), and Red-shouldered Hawk (Peery et al. 2006). Reliable and unambiguous identification of murrelet nest predators requires the use of technology that records video and audio at known nest-sites during the breeding season (Hébert and Golightly 2006, Ball et al. 2008, Malt and Lank 2009, Richardson et al. 2009). This non- invasive monitoring method facilitates daily, up-close observations of the nest unlike other methods traditionally used to conduct terrestrial murrelet research (e.g. audio-visual surveys, radar surveys, radio telemetry). The predation event in 2010 would have escaped detection without an audio recording device in addition to the camera. However, even with the audio recorded, it was challenging to precisely understand events occurring at the nest without the aid of video. We required additional evidence obtained during tree climbs and the AV survey to interpret the 2010 nesting attempt. The chronology of the nest would not have been known without the combination of all of these pieces of evidence. Because nest failure is responsible for poor reproduction, and by inference, the continued population decline of murrelets in California, successful recovery will require that management strategies are directed at reducing nest predation (Nelson and Hamer 1995b, McShane et al. 2004, Hébert and Golightly 2006, Golightly and Gabriel 2009, USFWS 2009). Successful management of nest predation requires knowledge of the predators and their biology. Nest Initiation Based on video and audio recorded at the Davison Tree during the last 10 years, we conclude that it is possible that murrelets do not initiate a nest annually. In general, members of the family tend to lay 1 clutch each year (DeSanto and Nelson 1995). For murrelets, however, initiating nests annually may not be common. Variability in the proportion of the murrelet population breeding each year has been documented (Hébert and Golightly 2006, Peery and Henry 2009). Decreased breeding effort in murrelets has also been detected in years with

6 low prey availability (Peery et al. 2004a). Additionally, Steller’s Eiders (Polystica stelleri) and Dark-bellied Brant (Branta bernicla bernicla), two species of arctic waterfowl, forgo annual nest initiation in response to predation risk (Quakenbush et al. 2004, Spaans et al. 2006, Lima 2009). However, we cannot be certain that the pair did not actually initiate a nest in 2009. When a nest was not observed at the Davison Tree it was impossible to determine if the pair did not nest or if a nest was initiated in a different location. Risk of predation is the most commonly documented cause of nest abandonment in (Lima 2009), and for , nest-sites can be abandoned following a failed breeding attempt (Hedgren 1980, Harris et al. 1995). It’s possible that multiple years of nest failure at the Davison Tree had caused this pair to alter their nest-site location on the same branch in 2006, 2007, and 2009 (Golightly et al. 2008, Golightly and Schneider 2009). It is also possible that this murrelet pair had located and used an alternate nest-site somewhere else in RNSP. Originally, Golightly and Schneider (2009) suggested that the pause in breeding during 2006-2007 could have resulted from the death of the male murrelet. The logic was based on other seabird species with mate and site fidelity because fidelity is more likely to persist when both members of a pair survive to the next breeding attempt (Coulson and Thomas 1983, Aebischer et al. 1995). This original hypothesis seems less likely following the pause in breeding during 2009 unless 1) the original male of the pair died prior to 2006, 2) the female found a different male to mate with during 2008, then 3) the second male died before breeding in 2009. We confirmed that the original female was alive in 2009 to initiate a nest, however it was impossible to confirm the status of the original male. Longevity and Nest-site Fidelity Longevity remains unknown for murrelets, and despite long-term monitoring at this nest it could not be directly measured. Other species in the auk family have been documented to live for a range of 5-32 years (Clapp et al. 1982, DeSanto and Nelson 1995). The only documentation of murrelet longevity comes from the recapture of 2 banded individuals at a minimum age of 7 years (Cooke 1999) and this study. A banded murrelet was re-sighted at the Davison Tree in 2009, and we assumed this murrelet was the same individual banded in 2001 and re-sighted in this tree in 2003 and 2008. Banded in 2001, the female was identified as a breeding adult. Although the age of sexual maturity is not known for murrelets, it is commonly assumed to occur between the age of 2 and 4, generalizing from the life history characteristics of other alcids (DeSanto and Nelson 1995). This would suggest that, depending on age of sexual maturity, the female murrelet at our nest was a minimum of 10 to 12 years of age in 2009. Nest-site fidelity is common among both ground (e.g. Common Murre, Uria aalge; Birkhead 1977) and burrow nesting alcids (e.g. Razorbill, Alca torda, Harris and Wanless 1995; Black Guillemot, Cepphus grylle, Ewins 1989). Nest-site fidelity is a common life history trait in alcids and it is not surprising that tree-nesting murrelets return to the same nest-site in multiple years. Murrelets have been reported to exhibit fidelity to the same nest-stand (Divoky and Horton 1995) and to a lesser extent a specific nest-tree (Nelson and Peck 1995, Naslund et al. 1995, Burger et al. 2009). Moreover, our nest monitored in RNSP provides unequivocal evidence that an individual murrelet can exhibit fidelity to both a nest-branch and a nest-site for multiple consecutive years even when a nest is not initiated at that site annually (Hébert and Golightly 2006, Golightly et al. 2008, Golightly and Schneider 2009). The duration of fidelity to one site is not known (Hébert and Golightly 2006, Golightly et al. 2008, Golightly and Schneider 2009). For the last 7 of 10 years, the murrelet pair studied has nested on the same branch. Four consecutive breeding attempts (2001-2005) occurred in the

7 same exact location on the nest-branch. In 2008, following a two year period where no nesting was observed at this site (2006, 2007), the pair returned to nest; the egg was laid on the same branch 38 cm southeast of the original nest-site used in 2001-2005 (Figure 3). Although we did not document a nest in 2009, during the murrelet’s brief attendance of the site a whistle call was given. This call is often given during visits to a nest-site and incubation exchanges (Nelson 1997). Additionally, the murrelet assumed an incubatory posture in the exact location of the 2008 nest-site during this visit in 2009. In 2010, the exact location of the nest was unable to be determined; however it was probably on the same branch relatively close to microphone because landings by adult murrelets were clearly audible. Furthermore, the downy feather thought to belong to a young murrelet was found on the same nest-branch within 2 m of the 2008 nest-site. Regardless of the location of the nest in 2010, nest-branches used by murrelets possess multiple spots suitable where a nest may be initiated. Corvid Presence at the Nest-Site During 2009, a Gray Jay was recorded by the camera at the Davison Tree nest-site for the first time since monitoring began. Steller’s Jays have been regularly observed at the videoed nest each year, whereas ravens were only seen in association with predation events. Furthermore, Steller’s Jays were audible in the immediate vicinity of the tree on over 90% of days monitored, but ravens and Gray Jays were heard much less often. Although each of these corvid species contribute to predation risk at murrelet nests, a recent investigation of murrelet nest predators using artificial nests reported that Steller’s Jay were responsible for regional patterns of predation risk (Malt and Lank 2009). Additionally, Steller’s Jays are more abundant in forested systems than in the past (see George 2009). Thus we conclude that corvids, and particularly Steller’s Jays, are the species with the greatest impact on the survival of murrelet nests in California and southern Oregon. The recent increase in Gray Jay presence is difficult to interpret in terms of potential contribution to predation risk. Gray Jays in murrelet habitat may increase predation risk, particularly for chicks. ACKNOWLEDGMENTS This research was funded by grants and in-kind contributions from the California Department of Fish and Game and in cooperation with the National Park Service, and Humboldt State University. We thank A. Trost, C. Lockerby, and L. Tucci for their assistance both in the field and with video analysis. We thank M. Nichols and N. Williamson for improvements in our color camera system. Additional help in developing the camera system was provided by M. Cunha. We thank S. Sillett who climbed the tree and installed and repaired the camera at the nest-site. We especially thank P. Hébert who assisted with the original camera installation and subsequent monitoring at the nest in 2001-2004. For facilitation of this project, we thank T. Hofstra of Redwood National and State Parks. Finally, we thank E. Burkett (California Department of Fish and Game, Sacramento) and L. Roberts (U.S. Fish and Wildlife Service, Arcata, California) for their support. This work was conducted under the Humboldt State University Institutional Care and Use Protocol (08/09.W.57.A), as well as permits from the National Parks Service (Scientific Collecting Permit REDW-2009-SCI-0014 and REDW- 2010-SCI-0011) and U.S. Fish and Wildlife Service (Section 10a Permit TE-040193-5).

8 LITERATURE CITED Aebischer, N.J., G.R. Potts, and J.C. Coulson. 1995. Site and mate fidelity of shags Phalacrocorax aristotelis at two British colonies. Ibis 137:19-29.

Ball, J.R., E.M. Bayne, and C.S. Machtans. 2008. Video identification of boreal forest songbird predators and discordance with artificial nest studies. Proceedings of the Fourth International Partners in Flight Conference: Tundra to Tropics 37-44.

Bent, A.C. 1946. Life histories of North American jays, crows, and titmice, part I. Smithsonian Institution United States National Museum Bulletin 191. Dover Publications, Mineola, New York.

Binford, L.C., B.G. Elliot, and S.W. Singer. 1975. Discovery of the nest and downy young of the Marbled Murrelet. Condor 87:303-319.

Birkhead, T.R. 1977. The effect of habitat and density on breeding success in the Common Gulliemot (Uria aalgae). Journal of Animal Ecology 46:751-764.

Bradley, R.W., and V. Bahn. 2004. Inland habitat associations of marbled murrelets on southwest Vancouver Island, British Columbia. Journal of Field Ornithology 75:53-66.

Burger, A.E. 2002. Conservation assessment of the Marbled Murrelet in British Columbia, a review of biology, populations, habitat associations, and conservation. Technical Report Series No. 387. Canadian Wildlife Service, Pacific and Yukon Region, British Columbia.

Burger, A.E., I.A. Manley, M.P. Silvergieter, D.B. Lank, K.M. Jordan, T.D. Bloxton, and M.G. Raphael. 2009. Re-use of nest sites by Marbled Murrelets (Brachyramphus marmoratus) in British Columbia. Northwestern Naturalist 90:217-226.

California Fish and Game Commission. 1992. of California declared to be endangered or threatened. Government Code Section 11346.2 (d), Regulation 92:1-8.

Carter, H.R., and R.A. Erickson. 1992. Status and conservation of the Marbled Murrelet in California, 1982-1987. Proceedings of the Western Foundation of Vertebrate Zoology 5:92-108.

Carter, H.R., and K.J. Kuletz. 1995. Mortality of Marbled Murrelets due to oil pollution in North America. Pages 261-269 in C.J. Ralph, G.L. Hunt, M. Raphael, and J.F. Piatt, editors. Ecology and conservation of the Marbled Murrelet. USDA Forest Service General Technical Report PSW-152. USDA Forest Service, Albany, California.

Carter, H.R., M.L.C. McAllister, and M.E. Isleib. 1995. Mortality of Marbled Murrelets in gill nets in North America. Pages 99-112 in C.J. Ralph, G.L. Hunt Jr., M.C. Raphael, and F.J. Piatt, editors. Ecology and conservation of the marbled murrelet. USDA Forest Service General Technical Report PSW-152. USDA Forest Service, Albany, California.

9 Carter, H.R., and J.L. Stein. 1995. Molts and plumages in the annual cycle of the Marbled Murrelet. Pages 99-109 in C.J. Ralph, G.L. Hunt, Jr., M.G. Raphael, and J.F. Piatt, editors. Ecology and conservation of the Marbled Murrelet. USDA Forest Service General Technical Report PSW-152. USDA Forest Service, Albany, California.

Clapp, R.B., M.K. Klimkiewicz, J. H. Kennard. 1982. Longevity records of North American birds: Gaviidae through Alcidae. Journal of Field Ornithology 53: 81-124.

Cooke, F. 1999. Population studies of Marbled Murrelets (Brachyramphus marmoratus) in British Columbia. Pages 43-51 in A.W. Diamond and D.N. Nettleship, editors. Biology and Conservation of Forest Birds. Society of Canadian Ornithologists Special Publication No. 1, Fredericton, New Brunswick.

Coulson, J.C., and C.S. Thomas. 1983. Mate choice in the Kittiwake gull. Pages 361-376 in P.P.G. Bateson, editor. Mate Choice, Cambridge University Press, Cambridge, United Kingdom.

DeSanto, T.L., and S.K. Nelson. 1995. Comparative reproductive ecology of the (Family Alcidae) with emphasis on the Marbled Murrelet. Pages 33-47 in C.J. Ralph, G.L. Hunt, Jr., M.G. Raphael, and J.F. Piatt, editors. Ecology and conservation of the Marbled Murrelet. USDA Forest Service General Technical Report PSW-152. USDA Forest Service, Albany, California.

Divoky, G.J., and M. Horton. 1995. Breeding and natal dispersal, nest habitat loss and implications for Marbled Murrelet populations. Pages 83-88 in C.J. Ralph, G.L. Hunt, Jr., M.G. Raphael, and J.F. Piatt, editors. Ecology and conservation of the Marbled Murrelet. USDA Forest Service General Technical Report PSW-152. USDA Forest Service, Albany, California.

Ewins, P.J. 1989. The breeding biology of Black Guillemots (Cepphus grylle) in Shetland. Ibis 131:507-520.

Falxa, G. Endangered Species Biologist, U.S. Fish and Wildlife Service, Arcata, California [Personal Communication].

Falxa, G.A., J. Baldwin, D. Lynch, S.K. Nelson, S.L. Miller, S.F. Pearson, M.G. Raphael, C. Strong, T. Bloxton, B. Galleher, B. Hogoboom, M. Lance, and R. Young. 2009. Marbled murrelet effectiveness monitoring, Northwest Forest Plan: 2008 summary report. Pacific Northwest Forest Plan Interagency Regional Monitoring Program.

George, T.L. 2009. Corvid abundance and management. Pages 15-42 in M.A. Colwell, T.L. George, and R.T. Golightly, editors. A predator management strategy to address corvid impacts on productivity of Snowy Plovers (Charadrius alexandrinus) and Marbled Murrelets (Brachyramphus marmoratus) in coastal northern California. Report submitted to U.S. Fish and Wildlife Service, Arcata, California.

Golightly, R.T., and P.O. Gabriel. 2009. Marbled Murrelets. Pages 65-106 in M.A. Colwell, T.L. George, and R.T. Golightly, editors. A predator management strategy to address corvid impacts on productivity of Snowy Plovers (Charadrius alexandrinus) and Marbled Murrelets

10 (Brachyramphus marmoratus) in coastal northern California. Report submitted to U.S. Fish and Wildlife Service, Arcata, California.

Golightly, R.T., C.D. Hamilton, and P.N. Hébert. 2009. Characteristics of Marbled Murrelet (Brachyramphus marmoratus) habitat in northern California. Report to the National Parks Service, Orick, California and California Department of Fish and Game, Sacramento, California.

Golightly, R.T., P.N. Hébert, and C.D. Hamilton. 2008. Long-term Monitoring of a Marbled Murrelet nest in northern California. Report to the California Department of Fish and Game, Sacramento, California.

Golightly, R.T., and S.R. Schneider. 2009. Observations of incubation in year 8 of a long-term monitoring effort at a marbled murrelet nest in northern California. Report to the California Department of Fish and Game, Sacramento, California.

Gutzwiller, K.J., S.K. Riffell, and S.H. Anderson. 2002. Repeated human intrusion and the potential for nest predation by Gray Jays. The Journal of Wildlife Management 66: 372-380.

Hamer, T.E., and S.K. Nelson. 1995. Nesting chronology of the Marbled Murrelet. Pages 49-56 in C.J. Ralph, G.L. Hunt, M. Raphael, and J.F. Piatt, editors. Ecology and conservation of the Marbled Murrelet. USDA Forest Service General Technical Report PSW-152. USDA Forest Service, Albany, California.

Harris, M.P., and S. Wanless. 1995. Survival and non-breeding of adult Common Guillemot Uria aalgae. Ibis 137:192-197.

Harris, M.P., S. Wanless, and T.R. Barton. 1995. Site use and fidelity in the Common Guillemot Uria aalgae. Ibis 139:399-404.

Harris, S.W. 1996. Northwestern California birds. 2nd edition. Humboldt State University Press, Arcata, California.

Hébert, P.N., and R.T. Golightly. 2006. Movements, nesting, and response to anthropogenic disturbance of Marbled Murrelets (Brachyramphus marmoratus) in Redwood National and State Parks, California. Unpublished report, Department of Wildlife, Humboldt State University, Arcata, California and California Department of Fish and Game Report 2006-02, Sacramento, California.

Hébert, P.N., and R.T. Golightly. 2007. Observations of predation by corvids at a Marbled Murrelet nest. Journal of Field Ornithology 78:221-224.

Hedgren, S. 1980. Reproductive success of Guillemots Uria aalge on the island of Stora Karlso. Ornis Fennica 57:49-57.

Henske E.J., S.K. Robinson, and J.D. Brawn. 2001. Nest predation and neotropical migrant songbirds: Piecing together the fragments. Wildlife Society Bulletin 29:52-61.

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Hunter, J.E., D. Fix, G.A. Schmidt, and J.C. Power. 2005. Atlas of the breeding birds of Humboldt County, California. Redwood Region Audubon Society, Eureka, California.

Ibarzabal, J. and A. Desrochers. 2004. A nest predator’s view of managed forest: Gray Jay (Perisoreus canadensis) movement patterns in response to forest edges. The Auk 121:162-169.

Jordan, K.M., and S.K. Hughes. 1995. Characteristics of three Marbled Murrelet tree nests, Vancouver Island, British Columbia. Northwestern Naturalist 76:29-32.

Kelson, J.D., I.A. Manley, and H.R. Carter. 1995. Decline of the Marbled Murrelet in Clayoquot Sound, British Columbia: 1982-1993. Northwestern Naturalist 76:90-98.

Kuzyakin, A.P. 1963. On the biology of the Marbled Murrelet. Ornitolgiya 6:315-320.

Lima, S.L. 2009. Predators and the breeding bird: Behavioral and reproductive flexibility under the risk of predation. Biological Reviews 84:485-513.

Malt, J.M., and D.B. Lank. 2009. Marbled Murrelet nest predation risk in managed forest landscapes: Dynamic fragmentation effects at multiple scales. Ecological Applications 19: 1274- 1287.

Manley, I.A. 1999. Behavior and habitat selection of Marbled Murrelets nesting on the sunshine coast. M.Sc. Thesis, Simon Fraser University, Canada.

Manley, I.A., and J.D. Kelson. 1995. Description of two Marbled Murrelet tree nests in the Walbran Valley, British Columbia, Canada. Northwestern Naturalist 76:26-28.

Marks, D.K., and N.L. Naslund. 1994. Sharp-shinned Hawk preys on a Marbled Murrelet nesting in old-growth forest. The Wilson Bulletin 106:565-567.

Marzluff, J.M., and E. Neatherlin. 2006. Corvid response to human settlements and campgrounds: Causes, consequences, and challenges for conservation. Biological Conservation 130:301-314.

Marzluff, J.M., and M. Restani. 1999. The effects of forest fragmentation on avian nest predation. Pages 155-169 in J.A. Rochelle, L.A. Lehmann, and J. Wisniewski, editors. Forest fragmentation: Implications for wildlife management. Brill Academic Publishers, Leiden, Netherland.

McShane, C., T. Hamer, H. Carter, G. Schwartzman, V. Friesen, D. Ainley, R. Tressler, S. Nelson, A. Burger, L. Spear, T. Mohagen, R. Martin, L. Henkel, K. Prindle, C. Strong, and J. Keany. 2004. Evaluation report for the 5-year status review of the Marbled Murrelet in Washington, Oregon, and California. Unpublished Report. EDAW, Inc., Seattle, Washington. U.S. Fish and Wildlife Service, Region 1, Portland, Oregon.

12 Miller, S. L., and C. J. Ralph. 1995. Relationship of Marbled Murrelets with habitat characteristics at inland sites in California. Pages 205-215 in C.J. Ralph, G.L. Hunt, M. Raphael, and J.F. Piatt, editors. Ecology and conservation of the Marbled Murrelet. USDA Forest Service General Technical Report PSW-152. USDA Forest Service, Albany, California.

Miller, S.L., C.J. Ralph, M.G. Raphael, C. Strong, C.W. Thompson, J. Baldwin, M.H. Huff, and G.A. Falxa. 2006. At-sea monitoring of Marbled Murrelet population status and trend in the Northwest Forest Plan area. Chapter 3 in M.H. Huff, editor. Northwest Forest Plan—the first 10 years (1994-2003): status and trend of population and nesting habitat for the Marbled Murrelet. USDA Forest Service General Technical Report PNW-650.

Naslund, N.L., K.J. Kuletz, M.B. Cody, and D.K. Marks. 1995. Tree and habitat characteristics and reproductive success at Marbled Murrelet tree nests in . Northwestern Naturalist 76:12-25.

Nelson S.K. 1997. Marbled Murrelet (Brachyramphus marmoratus). Volume 276 in A. Poole, and F. Gill, editors. The Birds of North America. Academy of Natural Sciences, Philadelphia, Pennsylvania. American Ornithologists’ Union, Washington, D.C.

Nelson S.K., and T.E. Hamer. 1995a. Nest success and the effects of predation on Marbled Murrelets. Pages 89-98 in C.J. Ralph, G.L. Hunt, M. Raphael, and J.F. Piatt, editors. Ecology and conservation of the Marbled Murrelet. USDA Forest Service General Technical Report PSW- 152. USDA Forest Service, Albany, California.

Nelson S.K., and T.E. Hamer. 1995b. Nesting biology and behavior or the Marbled Murrelet. Pages 57-67 in C.J. Ralph, G.L. Hunt, M. Raphael, and J.F. Piatt, editors. Ecology and conservation of the Marbled Murrelet. USDA Forest Service General Technical Report PSW- 152. USDA Forest Service, Albany, California.

Nelson S.K., and R.W. Peck. 1995. Behavior of Marbled Murrelets at nine nest sites in Oregon. Northwestern Naturalist 76:43-53.

Ouellet, H. 1970. Further observations on the food and predatory habits of the Gray Jay. Canada Journal of Zoology 48:327-330.

Peery, M.Z., S.R. Beissinger, E. Burkett, and S.H Newman. 2006. Local survival of Marbled Murrelets in central California: Roles of oceanographic processes, sex, and radiotagging. The Journal of Wildlife Management 70:77-88.

Peery, M.Z., S.R. Beissinger, S.H Newman, B.H. Becker, E. Burkett, and T.D. Williams. 2004a. Individual and temporal variation in inland flight behavior of Marbled Murrelets: Implications for population monitoring. Condor 106:344-353.

Peery, M.Z., S.R. Beissinger, S.H. Newman, E. Burkett, and T.D. Williams. 2004b. Appling the declining population paradigm: diagnosing the causes of poor reproduction in the Marbled Murrelet. Conservation Biology 18:1088-1098.

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Peery, M.Z., L.A. Hall, J.T. Harvey, and L.A. Henkel. 2008. Abundance and productivity of Marbled Murrelets off central California during the 2008 breeding season. Report submitted to California State Parks, Half Moon Bay, California.

Peery, M.Z., L.A. Hall, A. Sellas, S.R. Beissinger, C. Moritz, M. Bérubé, M.G. Raphael, S.K. Nelson, R.T. Golightly, L. McFarlane-Tranquilla, S. Newman, P.J. Palsbøll. 2009. Genetic analyses of historic and modern Marbled Murrelets suggests decoupling of migration and gene flow after habitat fragmentation. Proceedings of the Royal Society B. Online Journal, doi:10.1098/rspb.2009.1666.

Peery, M.Z., and W.R. Henry. 2010. Recovering marbled murrelets via corvid management: a population viability analysis approach. Biological Conservation 143:2414-2424.

Perry, D.A. 1995. Status of forest habitat of the Marbled Murrelet. Pages 381-383 in C.J. Ralph, G.L. Hunt, Jr., M.G. Raphael, and J.F. Piatt, editors. Ecology and conservation of the Marbled Murrelet. USDA Forest Service General Technical Report PSW-152. USDA Forest Service, Albany, California.

Quakenbush, L., R. Suydam, T. Orbitschkewitsch, and M. Deering. 2004. Breeding biology of Steller’s Eiders (Polystica stelleri) near Barrow, Alaska, 1991-99. Arctic 57:166-182.

Ralph, C.J., G.L. Hunt Jr., M.G. Raphael, and J.F. Piatt. 1995. Ecology and conservation of the Marbled Murrelet in North America: an overview. Pages 3-23 in C.J. Ralph, G.L. Hunt, Jr., M.G. Raphael, and J.F. Piatt, editors. Ecology and conservation of the Marbled Murrelet. USDA Forest Service General Technical Report PSW-152. USDA Forest Service, Albany, California.

Raphael M.G., D.E. Mack, J.M. Marzluff, and J.M. Luginbuhl. 2002. Effects of forest fragmentation on populations of the Marbled Murrelet. Studies in Avian Biology 25:221-235.

Richardson, T.W., T. Gardali, and S.H. Jenkins. 2009. Review and meta-analysis of camera effects on avian nest success. Journal of Wildlife Management 73:287-293.

Rodway, M.S., H.R. Carter, S.G. Sealy, and R.W. Campbell. 1992. Status of the Marbled Murrelet in British Columbia. Proceedings of the Western Foundation of Vertebrate Zoology 5:7-41.

Rogers, L.L. 2005. Weight-carrying ability and caching behavior of Gray Jays, Perisoreus canadensis: Adaptations to boreal winters. The Canadian Field-Naturalist 119:101-104.

Sealy, S.G. 1975. Egg size of murrelets. Condor 77:500-501.

Singer, S.W., N.L. Naslund, S.A. Singer, and C.J. Ralph. 1991. Discovery and observations of two tree nests of the Marbled Murrelet. Condor 93:330-339.

14 Spaans, B., H.J. Blijleven, I.U. Popov, M.E. Rykhlikova, and B.S. Ebbinge. 1998. Dark-bellied Brent Geese Branta bernicla bernicla forgo breeding when Arctic Foxes Alopex lagopus are present during nest initiation. Ardea 86:11-20.

Stauffer, H.B., C.J. Ralph, S.L. Miller. 2004. Ranking habitat for Marbled Murrelets: New conservation approach for species with uncertain detection. Ecological Applications 14:1374- 1383.

Strickland, D. 1991. Juvenile dispersal in Gray Jays: Dominant brood member expels siblings from natal territory. Canadian Journal of Zoology 69:2935-2945.

Strickland, D., and H. Ouellet. 1993. Gray Jay (Perisoreus canadensis). Volume 040 in A. Poole, and F. Gill, editors. The Birds of North America. Academy of Natural Sciences, Philadelphia, Pennsylvania. American Ornithologists’ Union, Washington, D.C.

Strong, C.S. 2003. Decline of the Marbled Murrelet population on the central during the 1990’s. Northwestern Naturalist 84:31-37.

U.S. Fish and Wildlife Service (USFWS). 1992. Endangered and threatened wildlife and plants; determination of threatened status for the Washington, Oregon, and California population of the Marbled Murrelet. Federal Register 57:45328-45337.

U.S. Fish and Wildlife Service (USFWS). 2009. Marbled Murrelet (Brachyramphus marmoratus) 5-year review. Unpublished report. U.S. Fish and Wildlife Service, Region 1, Lacey, Washington.

Waite, T.A. 1991. Economics and consequences of scatterhoarding in Gray Jays (Perisoreus canadensis). Ph.D. Thesis, Ohio State University, Columbus, Ohio.

Whitmore, S., and A.R. Smith. 1993. Polypodiaceae: Polypody family. Pages 100, 103 in J.C. Hickman, editor. The Jepson manual: Higher plants of California. University of California Press, Berkeley, California.

Zharikov, Y, D.B. Lank, F. Huettmann, R.W. Bradley, N. Parker, P. Yen, L. McFarlane- Tranquilla, and F. Cooke. 2006. Habitat selection and breeding success in a forest-nesting alcid, the Marbled Murrelet, in two landscapes with different degrees of forest fragmentation. Landscape Ecology 21:107-120.

15 FIGURES AND TABLES

Figure 1. A diagram of the digital video recording (DVR) system used to monitor Marbled Murrelet activity at the Davison Tree, Redwood National and State Parks, Orick, California. This device was placed in the field and used to record and store continuous video footage of the nest during nesting season.

16

Figure 2. Chronology of events at the Davison Tree in 2010, Redwood National and State Parks, Orick, California. This timeline includes all major events, such as presence of a tree-climber, a Marbled Murrelet (MAMU) observed on camera, a corvid observed on camera, and predation of the murrelet nest. The occurrence of a major event is indicated by an arrow and accompanied with text describing the event. This timeline also includs all other events such audible landings, wing beats, and calls made by murrelets. The occurrence of landings, wing beats, and calls by murrelets are indicated using a dot (•). Additionally, days that the monitoring system failed to record video or audio are indicated by gray shading in the rows labeled Video and Audio.

17

Figure 3. Exact nest-site locations for nesting attempts recorded by camera (2001-2005, 2008) at the Davison Tree in Redwood National and State Parks, Orick, California. In 2010, the exact location of the nest was unknown since it was initiated beyond the camera’s field of view. Although a nest was not located a downy feather, presumably from a young murrelet, was found approximately 2 m from the 2008 nest-site. In 2006, 2007, and 2009 there was no documented nesting on this branch.

18

Figure 4. Photograph of the downy feathers, presumably from a young Marbled Murrelet, found by the tree climber on 30 June 2010 at 11:00 PDT approximately 2 m from the location of nest-site initiated in 2008 in the Davison Tree, Redwood National and State Parks, Orick, California. The increments on the ruler are in millimeters.

19 35 Steller's Jay 30 Common Raven Gray Jay 25

20

15

10

Average Vocalization Index Vocalization Average 5

0 1 2 3 4 5 6 7 8 9 10 11

May June July

Figure 5. Average vocalization index for each corvid species during each week of monitoring at the Davison Tree, Redwood National and State Parks, Orick, California. For each corvid species, calls audible 15 min before and 15 min after sunrise were noted during each morning audio was recorded between 3 May and 13 July. The vocalization index was calculated based on the percentage of 30 1-min intervals that vocalizations were detected in each morning sampled.

20 Table 1. Summary of audio recorded by the monitoring system on 30 June 2010 that facilitated the deduction that a Marbled Murrelet nest was initiated, an egg hatched, and then a chick was predated by one or more Gray Jays in the Davison Tree.

Time Start (h:mm:ss) Duration Description 6:00:20 0:00:30 Very quiet GRAJ vocalization, distant 6:00:54 0:00:01 Quiet GRAJ vocalization, distant 6:00:57 0:00:01 Quiet GRAJ vocalization, distant 6:01:09 0:00:01 MAMU and GRAJ interacted vocally, and potentially physically 6:01:25 0:00:01 GRAJ vocalization 6:01:50 0:00:16 MAMU and GRAJ interacted vocally, and potentially physically 6:02:06 0:00:03 MAMU chick called, continuous 6:02:11 0:00:09 MAMU and GRAJ interacted vocally, and potentially physically 6:02:17 0:00:02 Quiet GRAJ vocalization, not distant 6:02:21 0:00:18 MAMU chick called, continuous and loud 6:02:31 0:00:01 2 vocalizations heard, not sure if they were GRAJ or MAMU 6:02:41 0:00:25 MAMU and GRAJ interacted vocally, and potentially physically 6:03:07 0:00:43 Loud GRAJ vocalization, MAMU chick sounds 6:03:33 0:00:02 MAMU chick called, chick vocalizations became more distant 6:03:50 0:00:40 Quiet GRAJ vocalization, distant 6:04:32 0:00:03 MAMU wing beats 6:04:35 0:00:56 Silence 6:05:31 0:00:33 Quiet GRAJ vocalization, distant 6:07:07 0:00:03 Quiet GRAJ vocalization, distant 6:22:24 0:00:01 MAMU wing beats 6:31:49 0:00:01 Loud MAMU wing beats 6:44:55 0:00:01 MAMU wing beats

21 Table 2. Summary of documented nest fates (2001-2010) for the Marbled Murrelet nest monitored in Redwood National and State Parks, Orick, California. The species listed in parenthesis next to the cause of failure is the species responsible for the predation event.

Year Nest Fate Cause of Failure 2001 Chick Fledged (26 June) - 2002 Failed at Egg Stage Predation (Steller’s Jay) 2003 Chick Fledged (4 July) - 2004 Failed at Egg Stage Predation (Common Raven) 2005 Failed at Egg Stage Predation (?) 2006 No Nesting - 2007 No Nesting - 2008 Failed at Egg Stage Predation (Steller’s Jay) 2009 No Nesting - 2008 Failed at Chick Stage Predation (Gray Jay)

22