Please cite as: Gibson, G.C. 2002. Migration Monitoring at Rocky Point Bird Observatory in 2001. 16 pp., plus appendices. Rocky Point Bird Observatory, Metchosin, B.C.
| Appendix I | Staff and volunteer coverage at RPBO in 2001 |
| Appendix II | Letter to the President (RPBO) |
| Appendix III | All species recorded at RPBO in 2001 |
This report outlines the activities of the migration monitoring program at Rocky Point Bird Observatory (RPBO) in 2001. The primary research conducted at RPBO involves the monitoring of migrant songbirds that pass through the Rocky Point area on their fall journey south. The Observatory also plans to monitor spring migrants in the near future. By following a standardized protocol (seven hours of daily field-observation and bird banding/seven days a week), staff and volunteers document the number of individuals of each species that are banded and/or observed within the station’s well-defined ‘count’ area. This data is then analysed and compared with data from previous years in order to study long-term population trends for a select number of ‘target’ species. The Observatory completed its eighth year of monitoring in 2001. Although the field-work is focused on collecting data on migrant songbirds, staff and volunteers also monitor raptor and waterbird migration. This report summarizes the data collection phase of the work.
Situated at the southern tip of Vancouver Island, British Columbia, Canada, the RPBO study site is located on the property of the Canadian Forces Ammunition Depot (CFAD - Rocky Point), a base under the administration of the Department of Defense (DND). The program in 2001 was operated in a similar manner to previous years. There were some exceptions, including a few recommended changes to the operation’s protocol (not detailed in this report). The most significant variation from recent years, however, was the early conclusion of the field season in 2001 as a result of the tragic events that took place in New York and Washington. On October 7th the Rocky Point base became ‘off-limits’ to all non-military personnel. As such, RPBO staff and volunteers were unable to access the field-site and so migration coverage concluded two weeks earlier then scheduled. As a result, some late-migrants were not covered as thoroughly this fall compared to other years.
Field work and data collection was conducted on-site from July 23rd to October 7th for a total of 77 days of consecutive coverage (excluding September 12th and 13th). During this time, 2576 birds of 54 species and forms were banded and 177 species were recorded (banded, observed, heard) in the official ‘count’ area. The ‘back-nets’ (11-13) were operated on alternate days in 2001. These nets will be run on a full-time basis in 2002.
Additional activities at RPBO in 2001 included some new developments on the RPBO website; the submission of daily raptor counts to a web-based organization in the U.S., as well as other projects both large and small. There were many improvements to the field station this year, including the acquisition of a fifth-wheel trailer, which has dramatically improved on-site living and work conditions; the purchase and installation of a solar panel, inverter and battery storage system for the trailer; the purchase of a new laptop computer for use at the field station, as well as many other upgrades. A number of government departments and ministries, public and private institutions, and many individuals continued to lend valuable support to the Observatory, and RPBO received support from many new sources in 2001 as well.
In all, 55 volunteers and one staff member contributed 375 person-days of field-work to the migration monitoring program at Rocky Point in 2001. Of this total, volunteers contributed 300 person-days.
The 2001 migration monitoring season at Rocky Point began this year on July 23rd. A full morning of coverage that day included a daily census, six hours of constant-effort mist-netting and banding, as well as additional field observations by staff and volunteers. The migration crew followed this same protocol over the course of the next twelve weeks. Below is a summary of some of the trends and highlights encountered during the field-season.
JULY
Bird activity on the Point during the first week of coverage was quite steady for the time of year, with a good diversity of songbirds filtering through the census area on a daily basis (see Table 2). Wilson’s and Orange-crowned Warblers were most in evidence along with small numbers of other local breeding birds, including Townsend’s and Mac-Gillivray’s Warbler; Bewick’s Wren; Pacific-slope Flycatcher, as well as Song and White-crowned Sparrows. While the banding totals for the week suggest it was a busy start to the season compared to previous years, it’s clear that most of this activity is attributable to post-breeding dispersal. Many recently fledged young and small family groups dominated in the field, and most adult birds were actively moulting, which songbirds usually compete before they begin migration in the fall.
The monitoring crew observed a steady flight of Rufous Hummingbirds moving through the ‘census’ area (10 to 15 individuals each day), as well as a variety of swallows. Pacific-slope Flycatchers were active, with 23 individuals banded during the week and with an Estimated Total (ET) of 27 birds on July 24th. Common Nighthawks, another early migrant, were also seen in small groups. A small increase in the number of waders occurred during the week as well, including 6 Semipalmated Plover and a Pectoral Sandpiper recorded on the 28th and 30th, respectively.
AUGUST
There was a brief lull in activity during the first few days of August. Orange-crowned Warblers were reduced to an ET of eight on the last day of July and Wilson’s Warblers also tapered off slightly, although both species rallied after a few days of rain on August 2nd - 4th. Flycatchers were mostly absent for the first few days of the month, although they also picked up, with an impressive tally of seven Olive-sided Flycatchers observed on the 4th. The variety of flycatcher species also improved, with the season’s first Willow Flycatcher observed on the 1st and the first Western Wood-Pewee on the 4th.
Clear, dry conditions returned on August 5th along with a substantial increase in bird activity. A nice variety of warblers were seen that morning, including Orange-crowned (13 Banded/ 22 ET); Wilson’s (7/12); Common Yellowthroat (1/10); MacGillivray’s (2/6); Townsend’s (0/3); "Audubon’s" (0/3) and Yellow (0/1). A Blackpoll Warbler was observed on the 6th - only the second RPBO record to-date. This increased activity continued and, on August 7th, the migration crew had it’s second busiest banding day of the season, with 72 birds banded of sixteen species. Wilson’s Warblers (20/40) were most active, along with Orange-crowned (11/24) and MacGillivray’s (5/8). Fly-catchers were also quite numerous, with ten individuals banded (7 Pacific-slope, 2 Willow and 1 Hammond’s). The autumn’s first influx of Chipping Sparrows was recorded on the 4th, with 32 individuals counted in the area. A sea-watch highlight during the week was a single Cassin’s Auklet observed on the 4th. Other interesting sightings included a Semipalmated Sandpiper and a Caspian Tern on the 6th.
Table 1. Total of all birds banded at RPBO in 2001, by species.
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| Sharp-shinned Hawk |
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Cedar Waxwing |
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| Cooper’s Hawk |
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Orange-crowned Warbler |
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| Northern Pygmy-Owl |
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Yellow Warbler |
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| Hairy Woodpecker |
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"Western" Palm Warbler |
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| "Traill’s" Flycatcher1 |
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Yellow-rumped Warbler2 |
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| Hammond’s Flycatcher |
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Black-throated Grey Warbler |
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| Pacific-slope Flycatcher |
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Townsend’s Warbler |
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| Cassin’s Vireo |
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MacGillivray’s Warbler |
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| Hutton’s Vireo |
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Common Yellowthroat |
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| Warbling Vireo |
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Wilson’s Warbler |
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| Steller’s Jay |
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Black-headed Grosbeak |
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| N. Rough-winged Swallow |
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Spotted Towhee |
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| Cliff Swallow |
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Chipping Sparrow |
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| Barn Swallow |
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Savannah Sparrow |
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| Chestnut-backed Chickadee |
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Fox Sparrow |
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| Common Bushtit |
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Song Sparrow |
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| Red-breasted Nuthatch |
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Lincoln’s Sparrow |
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| Brown Creeper |
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White-crowned Sparrow |
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| Bewick’s Wren |
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White-throated Sparrow |
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| House Wren |
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Golden-crowned Sparrow |
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| Winter Wren |
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Dark-eyed Junco3 |
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| Marsh Wren |
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Red-winged Blackbird |
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| Golden-crowned Kinglet |
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Brown-headed Cowbird |
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| Ruby-crowned Kinglet |
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Purple Finch |
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| Swainson’s Thrush |
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House Finch |
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| Hermit Thrush |
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Pine Siskin |
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| American Robin |
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American Goldfinch |
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| Total Banded |
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| Species & Forms |
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| Bold — first banding record for species at RPBO. | Underline — season-high banding total for species |
3 "Oregon"
There was a gradual decrease of resident breeding birds in the area during the second week of August. Swallows and hummingbirds were also seen with less frequency. At the same time, a variety of species began to appear in larger numbers, including Yellow, Townsend’s and MacGillivray’s Warbler and Hammond’s and Willow Flycatcher. Included in this trend were some unusual records, including a Dusky Flycatcher; 2 Sandhill Crane; 2 Great Egret (the first record for RPBO) and 5 Black Scoter observed on August 11th, along with a Black-legged Kittiwake, Short-eared Owl, and Sanderling on the 12th.
The weather played a more prominent role during the third week in August, with strong winds from the west affecting migration coverage on the 16th and 17th (a number of nets were closed because of high winds), and no mist-netting was conducted on the 22nd and 23rd due to persistent and sometimes heavy rain showers. Despite this, the migration team still recorded a good variety of species throughout the week. Seven species of warbler were documented on August 18th and 19th, along with five flycatcher species. Sparrow totals fluctuated, with White-crowned and Chipping Sparrows seen in groups of up to thirty on a number of days, along with small groups of Song and Savannah Sparrow. The first Lincoln’s Sparrow of the fall was recorded on the 18th.
Table 2. Banding totals, net hours, and birds/net hour at RPBO in 2001, by date.
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| Jul 23-Jul 30 |
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.58 |
| Jul 31-Aug 7 |
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.57 |
| Aug 8-Aug 15 |
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.48 |
| Aug 16-Aug 23 |
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.56 |
| Aug 24-Aug 31 |
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.38 |
| Sep 1-Sep 8 |
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1.05 |
| Sep 9-Sep 16 |
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.47 |
| Sep 17-Sep 24 |
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.63 |
| Sep 25-Oct 2 |
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.55 |
| Oct 3-Oct 7 |
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1.00 |
| Total |
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.60 |
The busiest day of songbird activity during this period was August 19th. Pacific-slope Flycatchers (13/25) were active again, along with a steady supply of warblers, including Orange-crowned (8/17); Yellow (4/8); Black-throated Gray (2/3); and Wilson’s (5/10), as well as ones and twos of Townsend’s, MacGillivray’s and Common Yellowthroat. In all, 74 individuals of 20 species were banded, with 81 species observed in the area during the day. This activity, however, did taper off again towards the end of the month. In fact, considering the banding totals and capture rate for the period (Table 2), the last week of August appears to have been the quietest time for migrant songbird activity during the fall season.
While the last days of the month proved to be a quiet time for landbirds, there were many shorebirds observed in the area, along with good numbers of gulls and alcids. Eleven shorebird species were seen on Aug 29th, including a Wandering Tattler; Baird’s Sandpiper and Semipalmated Sandpiper. This may represent the highest total of shorebirds recorded in one day at Rocky Point. Gulls and alcids were numerous on the 31st, with 300 Rhinoceros Auklet and 250 Common Murre observed on the day, along with 600 Heermann’s; 400 Glaucous-winged, and 350 California Gulls.
SEPTEMBER
The first week of September turned out to be the most active period for migrants in 2001. Large numbers of birds were seen in the field and it was by far the busiest week of banding. Although the lull in activity during the previous week carried over to the first day of the month, this was to change on the morning of September 2nd, when the station experienced its first good ‘fallout’ of songbirds. Pacific-slope Flycatchers (32/57) made a fine showing on the day, as well as a host of other species, including Orange-crowned (14/30), Wilson’s (13/24) and Yellow Warbler (11/12); Winter Wren (9/32) and Hammond’s Flycatcher (4/16). Lincoln’s and White-crowned Sparrows were active; as well as Swainson’s Thrush, with seven individuals banded. All told, 126 birds were handled of 16 species on September 2nd, with 80 species observed in the field.
September 3rd was surprisingly quiet, yet things picked up again on the 4th and remained quite busy until the end of the week. Three days of military training were scheduled in the area from the 4th to the 6th, and so the migration crew ended coverage early on these days. A daily census was conducted, but only two hours of observation and banding, rather than the usual seven. Even with the reduced coverage, it was clear that there were many migrants moving through the area during this period, with Winter Wren; Lincoln’s Sparrow; Orange-crowned Warbler, and Swainson’s Thrush evident on all three days. As one indication of the activity during this period; there were 54 and 44 birds banded on September 4th and 5th respectively, with less than 20 total net hours recorded each day. By comparison, it required 78 net hours to capture 126 birds on September 2nd (the highest banding total this year).
Other bird sightings of note during the first week of September included the following: 4 Black Swift on September 1st; a Red-throated Loon on the 2nd; a single Baird’s Sandpiper on the 3rd; a Northern Pygmy Owl banded on the 5th, and an impressive 17 Sandhill Cranes observed on the 8th. Alcids and gulls were variable throughout the week, but a good number of alcids were seen on September 7th, with an ET of 820 Rhinoceros Auklet and 215 Common Murre recorded. Raptors began to move through the area, with 11 Red-tailed Hawks observed on September 8th along with 6 Sharp-shinned Hawks, 3 Cooper’s, and 50 Turkey Vultures.
Migration activity tapered off in the second week of September. Calm, clear weather conditions dominated, which was a change from the previous week, when the weather was generally unsettled, overcast and windy. It seems the fair conditions did little, once again, to prompt migrants during this period, and the census area remained relatively quiet until the 16th. Interestingly, this increase in bird activity coincided with the development of some frontal activity on that same day, with increased winds and overcast skies returning to the area. Of the birds that were on hand, sparrows were the most numerous, with lots of Savannahs and Lincoln’s observed, as well as increasing numbers of Spotted Towhee; Fox and Song Sparrow. The season’s first banded Golden-crowned Sparrow was handled on the 11th and, on that same day, the first White-throated Sparrow was observed in the field. It’s clear that sparrows dominated throughout the week when one looks at the banding totals for the period - of the 194 birds banded, ninety-nine were sparrows.
Migration monitoring coverage was interrupted on September 12th and 13th as a result of the tragic events that took place in New York and Washington. The military base was closed to all ‘non-military’ personnel, which meant there was no coverage whatsoever on these days. Official coverage resumed on the 14th.
Mid-month saw the arrival of small numbers of Yellow-rumped Warblers, increased numbers of American Robins and Pipits, as well as Ruby-crowned Kinglets and Hermit Thrushes. The first Varied Thrush of the fall was heard on the 16th. There was an increase in waterbird activity during the week, with gulls and alcids (mostly Heermann’s Gull and Common Murre) observed each day, as well as a greater variety of waterfowl, including ones and twos of Northern Pintail; Green-winged Teal, as well as Common, Hooded and Red-breasted Merganser. Four Common and two Pacific Loons were observed on September 16th along with 3 Surf Scoters. Turkey Vultures increased to an ET of 62 on September 15th.
The third week of September began on a busy note, with a good variety of sparrows encountered in the area on the morning of September 17th. Thirty sparrows were banded that day including Golden-crowned (9/15); Lincoln’s (7/13); Song (5/12); Savannah (4/9) and Fox (4/110). In all, 57 birds of sixteen species were banded on the 17th, with 65 species recorded in the count area. It was also active on the 18th, with 60 birds banded of fifteen species. Ruby-crowned Kinglets were more numerous, with 9 individuals banded on the day, along with a similar variety of warbler and sparrow species as on the 17th. Hermit Thrushes were more numerous on the 18th, with 7 banded (ET/9). Two Red-breasted Sapsuckers also made for a nice surprise and were among the 65 different species observed on the day. A similar variety of birds continued to move through the area during the following days, even as the weather turned from overcast, windy and dry conditions earlier in the week to overcast, calm and rainy weather by the morning of September 21st.
The first Broad-winged Hawk of the fall was observed on September 19th, although it was to be a few days before raptors began to appear in good numbers. On September 22nd the migration crew recorded 250 Turkey Vultures and 14 Red-tailed Hawks, as well as a small increase of accipiters and falcons. The vultures increased to 310 birds the following day. There was a fine showing of buteos on September 24th, with 17 Red-tailed and a season-high 7 Broad-winged Hawks observed. All told, there were ten raptor species recorded on the day. Additional observations during the week included a single Wood Duck on the 21st; a Townsend’s Solitaire and 3 Sandhill Cranes on the 22nd; the season’s first two Little Gulls on the 23rd, and a White-throated Sparrow banded on the 24th.
Relatively few songbirds were encountered in the area during the last week of September, with only small numbers of sparrows, Winter Wrens and Hermit Thrushes observed from the 24th — 29th. Ruby-crowned Kinglets began to increase in number, with 18 individuals banded on the 24th, although only 23 additional Ruby-crowns were banded during the next six days. The weather turned damp and overcast on the evening of the 25th, and these conditions persisted for three or four days, although the temperature remained fairly mild. While this situation proved unattractive for songbirds, it certainly didn’t discourage a wonderful variety of other species from making an appearance towards the end of the month, which made up for the blustery weather and unproductive banding.
Table 3. The 10 most abundant species banded in 2001 compared to previous years totals.
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Wilson’s Warbler |
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Orange-crowned Warbler |
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Winter Wren |
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Pacific-slope Flycatcher |
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Ruby-crowned Kinglet |
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American Goldfinch |
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Song Sparrow |
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Yellow Warbler |
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Lincoln’s Sparrow |
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Golden-crowned Kinglet |
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While only eleven birds were banded on September 29th, there were 78 different species observed in the field, including a nice variety of finches and sparrows. There was a lot of activity on the water as well, with six gull species and six alcid species recorded, including a single Cassin’s Auklet and an Ancient Murrelet. There was a great diversity of birdlife encountered the following day as well. On the last day of September a season-high total of 101 species were recorded in the area, including 38 waterbird species (gulls, alcids, waterfowl, etc.) and 63 landbird species. This group included 10 species of waterfowl; 10 raptor species; 8 sparrow and 7 gull species, as well as a number of unusual sightings - a single Swainson’s Hawk, a Parasitic Jaeger and two Sooty Shearwater.
OCTOBER
There was a noticeable increase of songbird activity in the area on the morning of October 1st, which coincided with the first cool temperatures of the year. The dawn temperature at Rocky Point remained above 10 C until the end of September, but by October 2nd the mercury had dropped to 5 C, where it remained for the rest of the week. The lull in activity during the previous week appears to have been associated with this weather system, wherein large numbers of songbirds that had been idle during the warm weather were given a push with the advancing front and markedly cooler temperatures. While this phenomenon doesn’t appear to influence songbird migration at Rocky Point to the same degree as other locations in Canada (Derbyshire 2000) (due to moderate seasonal/temperature variations on the West Coast), it seems clear that temperature may have played a fairly significant role on this occasion.
Ruby-crowned Kinglets; Golden-crowned Kinglets; Winter Wrens; Spotted Towhees, and a variety of other species began moving through the census area on October 1st. A comparison of the banding totals for three of these species; Ruby-crowned Kinglet; Winter Wren and Golden-crowned Kinglet, clearly reflects this dramatic increase. For instance; there were 115 Ruby-crowned Kinglets, 59 Winter Wrens, and 53 Golden-crowned Kinglets banded during the first week of October, compared with only 41, 21 and 18 individuals banded from September 24th-30th, respectively. This represents a capture rate of .54 birds per net hour for October compared to .20 birds per net hour in September for these three species - almost a three-fold increase. These totals also show that fifty-five percent of all the birds banded in October were members of this group, which indicates where the bulk of this activity originated.
At the same time, other species appeared in larger numbers - Hermit Thrush and Yellow-rumped Warbler, in particular - along with a continuing, steady supply of sparrows. Birds typically referred to as ‘diurnal migrants’ made an impressive appearance during the week (in the case of songbirds; species that gather in large, uniform groups that appear to continue actively migrating after sunrise); including American Robin; Cedar Waxwing; American Pipit, and Pine Siskin, among others. On the first of October, 240 American Robins were observed in the area, and this total increased to 300 birds on the 3rd. American Pipits were also numerous, with a season-high ET of 88 on the 3rd.
Pine Siskins appeared in large numbers on the 4th and continued to move through the area, peaking on October 5th with an ET of 650. A number of unusual species were noted during the week, including White-throated Sparrow (at least four individuals observed from the 2nd — 7th); a Little Gull observed on the 4th and a Rough-legged Hawk and three Red-throated Loons recorded on October 7th. A "Western" Palm Warbler was observed in the field (and then banded) on what turned out to be the final day of coverage in 2001 - October 7th, and represents the first individual of this species banded at Rocky Point.
Migration monitoring coverage concluded on October 7th; approximately two weeks earlier than scheduled. Information from previous years of monitoring suggest that the lack of coverage in October will likely impact on the value of the data collected in 2001 for some late-migrant species, including Ruby-crowned Kinglet; Hermit Thrush; members of the sparrow family; as well as Winter Wren and American Robin, among others. Though somewhat less critical, the coverage for many late-migrant and wintering waterbirds that frequent the Rocky Point area is also lacking this year. Furthermore, it’s evident from the bird activity in the area leading up to the 7th, as well as from incidental observations in the Victoria area after the 7th (in the vicinity of the field-station) that a considerable amount of bird migration took place during this time. At the same time, however, the two weeks that were missed in October represent less than a ten percent loss of coverage compared to the coverage obtained in 2000 and 1999.
Table 4. Season-high Estimated Totals (ET’s) for select species in 2001 compared to season-high ET’s in 2000 and 1999, including date.
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High ET 2001 |
|
2000 |
|
1999 |
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| Vaux’s Swift | 55 | Sep 8 | 450 | Sep 9 | 450 | Sep1 |
| Rufous Hummingbird | 18 | Jul 24 | 22 | Jul21 | 26 | Jul 26 |
| Northern Flicker | 15 | Oct 3 | 14 | Oct 5 | 60 | Sep 30 |
| Pacific-slope Flycatcher | 57 | Sept 2 | 40 | Aug 17 | 75 | Aug 30 |
| Warbling Vireo | 6 | Jul 25 | 13 | Sep 3 | 16 | Aug 14 |
| Steller’s Jay | 40 | Sep 30 | 35 | Sep 14 | 5 | Oct 8 |
| Purple Martin | 4 | Aug 5 | 11 | Aug 24 | 10 | Aug 18 |
| Violet-green Swallow | 220 | Aug 2 | 320 | Jul 28 | 135 | Jul 30 |
| N. Rough-winged Swallow | 60 | Aug 2 | 120 | Jul 28 | 150 | Aug 3 |
| Barn Swallow | 19 | Jul 29 | 48 | Jul 29 | 30 | Aug 3 |
| Winter Wren | 45 | Oct 7 | 85 | Aug 1 | 32 | Sep 30 |
| Golden-crowned Kinglet | 110 | Oct 7 | 85 | Sep 19 | 110 | Sep 30 |
| Ruby-crowned Kinglet | 70 | Oct 7 | 90 | Oct 1 | 65 | Oct 14 |
| Hermit Thrush | 9 | Oct 6 | 15 | Oct 2 | 8 | Sep 26 |
| American Robin | 300 | Oct 3 | 160 | Sep 26 | 660 | Oct 11 |
| Varied Thrush | 8 | Sep 17 | 10 | Sep 28 | 8 | Oct 11 |
| American Pipit | 88 | Oct 3 | 35 | Sep 23 | 80 | Sep 30 |
| Orange-crowned Warbler | 32 | Sep 2 | 67 | Aug 27 | 32 | Aug 31 |
| Yellow Warbler | 17 | Aug 13 | 80 | Aug 27 | 38 | Aug 30 |
| Yellow-rumped Warbler | 85 | Sep 30 | 80 | Sep 27 | 270 | Sep 30 |
| Townsend’s Warbler | 11 | Sep 7 | 16 | Aug 1 | 14 | Aug 14 |
| MacGillivray’s Warbler | 10 | Aug 6 | 8 | Aug 11 | 6 | Aug 17 |
| Wilson’s Warbler | 40 | Aug 7 | 20 | Aug 11 | 47 | Aug 14 |
| Spotted Towhee | 16 | Oct 2 | 20 | Sep 23 | 25 | Sep 27 |
| Savannah Sparrow | 40 | Sep 15 | 40 | Sep 19 | 90 | Sep 30 |
| Fox Sparrow | 15 | Oct 2 | 25 | Oct 1 | 45 | Sep 30 |
| Song Sparrow | 31 | Sep 30 | 25 | Oct 12 | 35 | Sep 27 |
| Lincoln’s Sparrow | 32 | Sep 2 | 65 | Sept 1 | 51 | Sep 30 |
| White-crowned Sparrow | 75 | Aug 28 | 50 | Sep 1 | 81 | Sep 27 |
| Golden-crowned Sparrow | 35 | Sep 30 | 16 | Sep 10 | 100 | Sep 27 |
| "Oregon" Junco | 50 | Sep 30 | 70 | Oct 10 | 105 | Sep 27 |
| Pine Siskin | 650 | Oct 5 | 160 | Oct 10 | 352 | Oct 16 |
In conclusion, the 2001 migration monitoring season at Rocky Point ran from July 23rd to October 7th. Field-work was conducted on 77 consecutive days (excluding September 12th and 13th), during which time 2576 birds of 54 different species and forms were banded. All told, 177 species were recorded (banded, observed, heard) in the official ‘count’ area.
Table 5. Coverage effort at RPBO in 2001 compared to 2000 and 1999.
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| 2000 |
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Red-throated Loon — a single bird on Sep 2nd; 3 birds on Oct 7th.
Sooty Shearwater — 2 birds on Sep 30th.
Great Egret — 2 birds on Aug 11th; first record for RPBO.
Wood Duck — a single bird on Sep 21st.
Black Scoter — 5 individuals on Aug 11th.
Broad-winged Hawk — a single bird on Sep 19th; a season-high 7 birds on Sep 24th.
Swainson’s Hawk — a single bird on Sep 30th.
Rough-legged Hawk — a single bird on Oct 7th.
Golden Eagle — a single bird on Sep 16th; 2 individuals on Oct 6th.
Sandhill Crane — 2 birds on Aug 11th; 17 birds on Sep 8th.
Wandering Tattler — a single bird on Aug 29th, 30th, 31st.
Semipalmated Sandpiper — a single bird on Aug 6th; 5 on Aug 28th; 3 on Aug 29th.
Baird’s Sandpiper — a single bird on Aug 29th and Sep 3rd.
Parasitic Jaeger — a single bird on Sep 30th.
Little Gull — 2 birds on Sep 23rd; a single on Oct 4th.
Herring Gull — an individual on Aug 11th & Sep 30th.
Western Gull — 2 birds on Aug 3rd; a single on Sep 29th.
Black-legged Kittiwake — a single bird on Aug 12th & 18th.
Caspian Tern — an individual on Jul 29th & Aug 6th.
Ancient Murrelet — a single bird on Sep 29th.
Cassin’s Auklet — an individual on Aug 4th & Sep 29th.
Mourning Dove — a single bird on Aug 4th & Sep 29th.
Barn Owl — a recently predated bird discovered on-site in mid-August
Short-eared Owl — a single bird on Aug 12th.
Northern Pygmy-Owl — an individual on Sep 5th; the first of this species banded at RPBO.
Red-breasted Sapsucker — 2 birds on Sep 18th; an individual on Sep 27th.
Hammond’s Flycatcher — a late individual on Oct 5th.
Dusky Flycatcher — a single bird observed on Aug 11th.
Pacific-slope Flycatcher — a late individual on Oct 4th.
Red-eyed Vireo — a single bird on Aug 27th.
Tree Swallow — 6 birds observed on Aug 12th.
Townsend’s Solitaire — a single bird on Sep 22nd.
"Western" Palm Warbler — a single bird on October 7th; first banding record for RPBO
Blackpoll Warbler — an individual on Aug 6th; only the second record for RPBO
White-throated Sparrow — single birds observed on Sep 11th & Oct 6th; individuals banded on Sep 24th, Oct 2nd & 4th; 2 banded on Oct 7th.
BACK-NET USAGE
Three additional mist-nets were established at Rocky Point at the start of the 2000 season, which increased the total number of nets operated at the station to thirteen. The ‘back-nets’ were set-up in order to increase the ‘sample size’ for some species that are not captured with much frequency in nets 1-10, as well as to optimize the banding component of the migration program generally. The ‘back-nets’ (11-13) are located in a more densely wooded area than the other nets, and have proven to be effective in catching a large volume and variety of songbirds. Not only have they generated useful data for some of the species that are captured in small numbers at the station to begin with (Black-throated Grey Warbler; Hammond’s Flycatcher and American Robin, for instance - see Table 6), they’ve also proven to be very productive in their own right and have improved the overall quality of coverage at the field-station in large measure.
The data obtained from the ‘back-nets’ in 2000 and 2001 suggest a few things already (although the nets will have to be operated in a standardized way for many years before trends become meaningful). All three nets were productive again in 2001, with capture-rates that compare favorably with the average of nets 1-10. The ‘back-nets’ were not as busy in 2001 as they were 2000. In both years, however, the average catch-rate of the ‘back-nets’ was noticeably greater than nets 1-10. In 2000, only one net in the group of ten (Net 7) had an individual capture-rate (.84) comparable to nets 11-13. And finally, this was the only net in 2000 (Net 7) with a higher capture-rate than the average rate for nets 11-13 in either year (see Derbyshire 2000).
It appears the location of the ‘back-nets’ was well-considered, both in light of their productivity, as well as for the diversity of species they have captured to date. This diversity has been good, with 32 species captured in nets 11-13 in 2001 out of a total of 54 species captured on the year (Nets 1-13). The totals were similar in 2000 (36 of 57 species). In this respect, the three ‘back-nets’ have helped to improve coverage for about 60% of all the species captured at the station, while operating only 50% of the time compared to nets 1-10.
When the ‘back-nets’ were introduced in 2000 the decision was made to alternate their use on a daily basis during their first two years of operation. Rather than an abrupt change from ten nets to thirteen, it was recommended that this transition be introduced over a two-year period in order to ‘mesh’ the data from year-to-year. This was done because the field-work conducted at RPBO — like most research — relies heavily on maintaining a ‘standardized’ approach to the data collection. By operating the ‘back-nets’ every second day during the 2000 and 2001 season, this helped to mitigate the impact of this change when it comes to analysis of the data in the future. Having now completed this two-year interim period, all thirteen mist-nets will be operated on a daily basis beginning in 2002.
Table 6. Back-net captures (Nets 11-13) in 2001 compared to 2000 [Per/total = ‘back-net’ captures as a percentage of total catch rate (Nets 1-13)], by species.
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| "Traill’s" Flycatcher | 1 | 1 | 2 | 8% | 5 | 20% | |
| Hammond’s Flycatcher | 2 | 2 | 3 | 7 | 29% | 13 | 41% |
| Pacific-slope Flycatcher | 17 | 13 | 25 | 55 | 29% | 95 | 41% |
| Cassin’s Vireo | 1 | 1 | 33% | ||||
| Chestnut-backed Chickadee | 3 | 2 | 6 | 11 | 22% | 33 | 47% |
| Common Bushtit | 4 | 3 | 7 | 10% | 21 | 53% | |
| Red-breasted Nuthatch | 2 | 2 | 40% | 3 | 60% | ||
| Brown Creeper | 1 | 2 | 3 | 30% | 1 | 9% | |
| Bewick’s Wren | 6 | 6 | 12 | 25% | 20 | 44% | |
| House Wren | 2 | 2 | 1 | 5 | 28% | 6 | 66% |
| Winter Wren | 16 | 3 | 14 | 33 | 16% | 52 | 19% |
| Marsh Wren | 1 | 1 | 14% | ||||
| Golden-crowned Kinglet | 13 | 7 | 13 | 33 | 35% | 35 | 43% |
| Ruby-crowned Kinglet | 21 | 12 | 14 | 47 | 25% | 76 | 25% |
| Swainson’s Thrush | 3 | 3 | 3 | 9 | 16% | 15 | 31% |
| Hermit Thrush | 5 | 6 | 4 | 15 | 35% | 14 | 26% |
| American Robin | 1 | 2 | 3 | 60% | 5 | 29% | |
| Orange-crowned Warbler | 12 | 4 | 12 | 28 | 13% | 35 | 28% |
| Yellow Warbler | 1 | 4 | 5 | 5% | 19 | 13% | |
| Black-thr. Grey Warbler | 1 | 1 | 1 | 3 | 50% | 4 | 80% |
| MacGillivray’s Warbler | 1 | 1 | 5 | 7 | 16% | 13 | 30% |
| Common Yellow throat | 2 | 1 | 1 | 4 | 4% | 4 | 6% |
| Wilson’s Warbler | 12 | 5 | 14 | 31 | 14% | 37 | 20% |
| Spotted Towhee | 11 | 3 | 4 | 18 | 28% | 25 | 25% |
| Chipping Sparrow | 2 | 2 | 18% | ||||
| Fox Sparrow | 3 | 3 | 6 | 12 | 17% | 16 | 20% |
| Song Sparrow | 10 | 5 | 7 | 22 | 20% | 33 | 27% |
| Lincoln’s Sparrow | 1 | 4 | 5 | 5% | 3 | 1% | |
| Golden-crowned Sparrow | 2 | 2 | 7% | 3 | 13% | ||
| "Oregon" Junco | 1 | 1 | 2 | 5% | 18 | 20% | |
| Purple Finch | 1 | 1 | 11% | 1 | 14% | ||
| Pine Siskin | 6 | 6 | 16% | ||||
| Banded — 2001 | 155 | 81 | 158 | 394 | |||
| Species | 28 | 22 | 24 | 32 | |||
| Net hours | 184 | 190 | 186 | 560 | |||
| Birds/net hour | .84 | .43 | .85 | .70 | |||
| Banded — 2000 | 243 | 150 | 227 | 620 | |||
| Species | - | - | - | - | |||
| Net hours | 231 | 231 | 230 | 692 | |||
| Birds/net hour | 1.05 | .65 | .98 | .89 |
Table 7. Capture rate for mist-nets 1-10 in 2001 compared to 2000 and 1999.
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Table 8. Capture rate for mist-nets 1-13 in 2001 compared to previous year.
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Table 9. Capture rate for mist-nets 11-13 (‘back-nets’) in 2001 compared to previous year.
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A great many positive developments took place at the RPBO field-station in 2001. The Observatory purchased a spacious new (1990) fifth-wheel trailer-home to replace the much smaller trailer that had served the station in previous years. The new trailer is a vast improvement in terms of the relative comfort of the Bander-in-Charge (BIC), who lives on-site during the three month field-season, but it has also benefited the program in many other ways. The trailer is large enough that a suitable work space is available, which now permits the BIC or volunteers to enter and/or proof data, etc., more effectively during the season, yet still leaves room for the BIC’s personal ‘space’ as well. Furthermore, the ‘old’ trailer will continue to be used on-site and will serve as an added incentive to attract long-term volunteers; which also benefits the program in terms of the quality and consistency of the field-work and data collection. Ten volunteers stayed in the trailer in 2001 for a period ranging from one night to two weeks.
Two other major acquisitions this year were also big factors in improving the field-station’s operation, including a new ‘laptop’ computer to be used on-site for data entry, as well as the purchase of a solar-panel, inverter, and additional battery storage for the site. This system was installed on the ‘new’ trailer at the beginning of the season and performed extremely well throughout the fall. It allowed for the regular use of the computer; the interior lights of both trailers; the phone charger, radio, etc., without having to transport batteries back and forth to be recharged, as in previous years. The computer was a great addition for data entry in general, but also permitted the BIC to generate a weekly migration summary for the RPBO website, as well as providing quick access to the Observatory’s historic banding, recapture and Estimated Total (ET) data.
On a final note, the two trailers were located in a slightly different setting this year; just across the access-road from where the old trailer was positioned in 2000. This re-location was requested by DND in order to reduce the visibility of the camp-site from the water.
There were many additional projects and developments at RPBO during the 2001 season that deserve mention. A ‘volunteer coordinator’ — Rick Schortinghuis — was elected from the Board of the Rocky Point Bird Observatory Society (RPBOS) and given the task of organizing the day-to-day staffing of the field-station to assure consistent coverage. A ‘volunteer’ drive was also organized in the spring by the President and Board, which helped to recruit many new volunteers for the 2001 season. These efforts were extremely valuable and were instrumental in providing a level and consistency of field-coverage in 2001 that has not been possible in years past.
The appointment of Rod Mitchell as ‘site coordinator’ proved invaluable insofar as general maintenance of the field-station was concerned. The ‘site-coordinator’ dealt with many important operation and logistics issues over the course of the year; ranging from site-preparation prior to the start of the season; maintenance and repair of station equipment; ongoing communication with the DND to ensure proper compliance with military directives, and many other tasks both large and small.
Other projects undertaken this year (above and beyond the usual) included, on-going fundraising; membership promotion; website development; the entry of all historic banding and recapture data onto computer; entering all 2001 banding and recapture data on computer in record time, along with many other activities.
The Rocky Point Bird Observatory continued to receive tremendous support in 2001 from many public and private organizations and institutions, as well as many individuals.
The operation of Rocky Point Bird Observatory depends on the help and support of many organizations and individuals. As a non-profit, volunteer-based cooperative with one seasonal staff member, the Observatory would not survive without the financial assistance of its generous benefactors, or without the remarkable commitment of the many organizations and volunteers that have contributed their time, experience and enthusiasm. With this in mind, I would like to thank the following: