By
Daniel Derbyshire
December 2000
Rocky Point Bird Observatory (RPBO) is located on Canadian Forces Ammunitions Depot (CFAD) Department of National Defence (DND) lands to the Southwest of Victoria, B.C. The habitat consists of old growth Douglas and Grand fir stands, tidal flats, endangered Garry Oak forests, open meadow and riparian habitats. Lying at the extreme southern tip of Vancouver Island, Rocky Point concentrates migrant passerines, raptors, and seabirds. The most common species banded during fall migration include: Wilson’s Warbler, Pacific-slope Flycatcher, Orange-crowned Warbler, Lincoln’s Sparrow, Savannah Sparrow and Ruby-crowned Kinglet. As of the fall of 2000, 267 bird species had been recorded, over 84 of which are suspected of breeding on the site.
The objective of the Rocky Point Bird Observatory is to monitor populations of passerines migrating along the west coast. The RPBO serves a broader purpose as a member of the Canadian Migration Monitoring Network (CMMN) managed by Bird Studies Canada (BSC). One objective of RPBO is to gather quality, standardized data on west coast migrating birds for the purpose of attaining population indices.
This report covers the migration monitoring season for fall 2000 as well as some analysis of data from previous years. Focusing more on the banding data than the Estimated Total data (ET), this report is not intended to assess populations but rather to draw some notable comparisons within the banding data.
In several of the data tables, the data has been adjusted according to "net set-up" where there is a comparison to previous years. At the present time, migration monitoring at Rocky Point is phasing in three additional nets with the standard array of ten. Therefore, for fall 2000 numbers of birds banded are somewhat inflated as compared to previous years. Thus when referring the year 2000 banding data to 1997 for example, the adjusted figures for nets 1-10 should be used. It should also be mentioned that much of the detailed historical banding and observational data was not available to the author at the time of writing this report.
Migration monitoring for fall 2000 began on July 21st and ended on October 18. As in previous years, late July was characterized by warm and sunny weather conditions and sparse numbers of migrants.
Rufous Hummingbird and swallows are generally the only species that show up in good numbers in late July and early August. Rufous Hummingbird peaked at 22 ET on July 21. A total of 125 Rufous Hummingbirds were captured this fall, the last one hit net 3 on September 1st. Volunteers and staff were witness to an impressive concentration of swallows on July 28 with 120 Northern Rough Winged and 320 Violet Green perched on the wires at the upper ponds. 48 Barn Swallows were observed the following morning of July 29th.
Late July and August featured an unusually high concentration of adult and Juvenile White Crowned and Chipping Sparrows. It was hoped that a good breeding season on southern Vancouver Island would translate further north, however this would not be the case as the migration of northern breeding sparrows was weak in September and October. August featured more periods of unsettled weather than in the past, however this did not make for more "fallout's." Wilson’s Warbler and Pacific Slope Flycatcher, the top migrants at Rocky Point in August were less apparent than in 1999. The season high total for Wilson’s was reached on August 11 with a paltry 20 birds estimated on the day. Pacific Slope Flycatcher peaked at 40 on August 17. These season highs were down considerably from last year. (See Table 1-3) Overcast conditions and moderate Southwest winds in the early morning hours of August 27th made for more a interesting morning for the RPBO crew. 41 birds were banded which ended up being the highest one-day banding total for August! On this day, season highs ETs were set for Yellow Warbler (80) and Orange Crowned Warbler (65). Despite high observation totals for these species, only 5 Yellow Warblers and 4 Orange Crowned Warblers were captured. This is becoming a more common phenomenon at Rocky Point whereby high numbers of birds are being observed but not captured. It is potentially a reflection of habitat change as the Alders and Willows have grown and gorse and broom have diminished in important areas. Also evident on the 27th of August was the season’s highest concentration of Western (128) and Least Sandpipers (20).
September is typically the busiest period of migration at Rocky Point. Sparrows, thrushes, and kinglets are expected to appear in high numbers. In 1999, July-August was the busiest period of the fall, which was a reversal of the "typical" pattern. It was hoped that breeding was more successful in the north for thrushes and sparrows, which were found in record low numbers one year ago. Things were promising early on when on September 1st, 65 Lincoln’s Sparrow and 50 White Crowned Sparrows were observed. As it turned out these would be season high tallies for these species! 107 birds were banded on September 3rd, included were: 10 Orange Crowned Warbler, 19 Yellow Warbler, 24 Lincoln’s, and 16 American Goldfinch. A respectable 450 Vaux’s Swifts were observed on September 9 and 19 Black Swifts were observed migrating over Juan De Fuca Strait on September 1st. On September 16, the second major fallout of passerines occurred when 97 birds of 20 species were banded. The remainder of September was rather quiet with daily totals averaging around 30 birds banded per day. Yellow Rumped Warbler migration was disappointing this season as the highest one day ET total was a mere 80 on September 27 as compared to 270 on September 30 in 1999. American Robin, White Crowned, Golden Crowned and Savannah Sparrows reached their season highs 2 weeks earlier in 2000 than in 1999. Robins peaked at 160 on September 26 as compared to 660 in 1999 on October 11. Similarly, White Crowned (81) and Golden Crowned Sparrows (100) peaked in 1999 on September 27th. In 2000, White Crowns peaked at 50 on September 1st and Golden Crowns at a low 16 on September 10. Weather in mid-late September was unusually dry with light winds and this may have been a major factor. In conclusion, September 2000 was rather disappointing as sparrows and thrushes never really materialized the way we had hoped. However, early October did manage to lift the spirits of the crew.
A storm front began moving in on September 28 and weather was unsettled for a period of days. With the first partial clearing overnight on September 30, Rocky Point experienced a heavy fallout on October 1st. 167 birds were banded including: 33 Winter Wren, 45 Ruby Crowned Kinglet, 10 Hermit Thrush, 15 Fox Sparrow, and 11 Spotted Towhee. Season highs were set on this day for Ruby Crowned Kinglet (90), Winter Wren (85), and Fox Sparrow (25). From October 1-3, 314 birds were banded at a rate of 1.5 captures/net hour, clearly the busiest period of the season. Hermit Thrush peaked at 15 on October 2nd. Oregon Junco were present in solid numbers this season and peaked at 70 on October 10. The big diurnal passages of American Robin, Yellow Rumped Warbler and Northern Flicker expected for October never happened.
Hawk migration is typically heaviest in late September. This year saw lower numbers of raptors but a stronger diversity of species. The first noticeable movement of raptors occurred on September 2nd with a trickle of accipiters and buteos. 15 Sharp Shinned Hawks were observed passing through Rocky Point on September 10, however the peak didn’t occur until October 7 when 18 were recorded. Cooper’s hawks reached a high count of 15 on October 2nd. 1300 Turkey Vultures in 1999 was not matched in 2000 as the maximum count was 350 this year, set on September 20. On October 10, 6 Broad Winged Hawks, 18 Red Tails and 3 Rough Legged Hawks were counted. Season high for Red Tailed Hawk was set on October 14th with 25 birds observed over the thermals.
Ocean going birds tend to concentrate off Rocky Point in late September and October. However, alcids and especially terns were very hard to find this season. Common Terns peaked for the season at a record low 11 on August 18. 480 Red Necked Phalaropes passed by Rocky Point on September 3rd. Cormorants were present this year in fairly good numbers with 250 Double Crested on September 25, 12 Pelagic on the 27th, and 120 Brandt’s Cormorant on October 15. Strong winds from the Northwest on September 30 produced: 5 Western Grebe, 130 Surf Scoter, 25 Green Winged Teal, 45 Black Turnstone and 1116 Greater White Fronted Geese. Grebes and Loons were found in low numbers this season. Only 1 Horned Grebe was observed this year and 3 Red Necked Grebe on September 9 was a season high. 15 Pacific Loon on October 16, and a meagre 8 Common Loon on October 15 were also season high totals. The highlight of the season for waterbirds was an impressive concentration of Gulls in mid-October. On October 16th, 2050 Heerman’s, 1080 Mew, 1600 California, 2000 Glaucous Winged Gulls and several thousand unidentified Gulls were observed off Edye Point and Cape Calver. Bonapartes Gulls put in a strong showing this season, peaking at 1330 on October 8. In terms of alcids, 550 Rhinoceros Auklets on August 17 was the highest ET total for the season. 735 Common Murre on October 8 was memorable.
In conclusion, it was another odd season with plenty of unusual deviations from the "norm." Estimated Totals for sparrows were low compared to previous years, although banding totals were average. Hermit and Swainson’s Thrushes once again turned up in very low densities as compared to earlier seasons at Rocky Point. In 1997, the Rocky Point crew banded a total of 40 Hermit Thrushes in one day, which is more than has been caught in a single season for years 1999 and 2000! It has become apparent that major "fallout's" of birds do not generally occur on mornings where there has been sudden overnight precipitation or heavy cloud. Rather, the causes of fallouts seem to be more complex involving more specific weather factors associated with the west coast. (e.g.. prevailing winds) As the migration monitoring program progresses at Rocky Point through the years (using standard protocols), we should be better able to deduce such factors involved in the migration of west coast songbirds. Tables 1, 2 and 3 show highest one-day ET figures for selected species in 1999 and 2000.
Table 1. Season high ET for species showing no significant variation between 1999 and 2000.
|
Species |
2000 |
Date |
1999 |
Date |
+/- |
| Vaux's Swift |
450 |
Sept 9 |
450 |
Sept 1 |
0 |
| Rufous Hummingbird |
22 |
July 21 |
26 |
July 26 |
-15 |
| Warbling Vireo |
13 |
Sept 3 |
16 |
Aug 14 |
-19 |
| Purple Martin |
11 |
Aug 24 |
10 |
Aug 18 |
+9 |
| Northern Rough Winged Swallow |
120 |
July 28 |
150 |
Aug 3 |
-20 |
| Golden Crowned Kinglet |
85 |
Sept 19 |
110 |
Sept 30 |
-23 |
| Ruby Crowned Kinglet |
90 |
Oct 1 |
65 |
Oct 14 |
+28 |
| Varied Thrush |
10 |
Sept 28 |
8 |
Oct 11 |
+20 |
| Townsend's Warbler |
16 |
Aug 1 |
14 |
Aug 14 |
+12 |
| MacGillivray's Warbler |
8 |
Aug 11 |
6 |
Aug 17 |
+19 |
| Spotted Towhee |
20 |
Sept 23 |
25 |
Sept 27 |
-20 |
| Song Sparrow |
25 |
Oct 12 |
35 |
Sept 27 |
-29 |
| Lincoln's Sparrow |
65 |
Sept 1 |
51 |
Sept 30 |
+22 |
Table 2. Season high ET for species showing marked increase between years.
|
Species |
2000 |
Date |
1999 |
Date |
+/- |
| Stellar's Jay |
35 |
Sept 14 |
5 |
Oct 8 |
+86 |
| Violet Green Swallow |
320 |
July 28 |
135 |
July 30 |
+58 |
| Barn Swallow |
48 |
July 29 |
30 |
Aug 3 |
+37 |
| Winter Wren |
85 |
Oct 1 |
32 |
Sept 30 |
+65 |
| Hermit Thrush |
15 |
Oct 2 |
8 |
Sept 26 |
+47 |
| Orange Crowned Warbler |
65 |
Aug 27 |
32 |
Aug 31 |
+51 |
| Yellow Warbler |
80 |
Aug 27 |
38 |
Aug 30 |
+52 |
Table 3. Season high ET for species showing marked decline between years.
|
Species |
2000 |
Date |
1999 |
Date |
+/- |
| Northern Flicker |
14 |
Oct 5 |
60 |
Sept 30 |
-77 |
| Pacific Slope Flycatcher |
40 |
Aug 17 |
75 |
Aug 30 |
-47 |
| American Robin |
160 |
Sept 26 |
660 |
Oct 11 |
-76 |
| American Pipit |
35 |
Sept 23 |
80 |
Sept 30 |
-56 |
| Yellow Rumped Warbler |
80 |
Sept 27 |
270 |
Sept 30 |
-70 |
| Wilson's Warbler |
20 |
Aug 11 |
47 |
Aug 14 |
-57 |
| Savannah Sparrow |
40 |
Sept 19 |
90 |
Sept 30 |
-44 |
| Fox Sparrow |
25 |
Oct 1 |
45 |
Sept 30 |
-44 |
| White Crowned Sparrow |
50 |
Sept 1 |
81 |
Sept 27 |
-39 |
| Golden Crowned Sparrow |
16 |
Sept 10 |
100 |
Sept 27 |
-84 |
| Oregon Junco |
70 |
Oct 10 |
105 |
Sept 27 |
-34 |
| Pine Siskin |
160 |
Oct 10 |
352 |
Oct 16 |
-55 |
Fall 2000, in true Rocky Point form featured the occurrence of many unusual species for Southern Vancouver Island. Only 1 Brown Pelican was observed in each of both 1999 and 2000 field seasons. This species was formerly much more common in September and October. (MGS reported Brown Pelican being "seen most days, including a flock of 68 on October 4" in 1997) New species for the Rocky Point list include; Glaucous Gull and Blackpoll Warbler. One Dusky Flycatcher, 2 White Throated Sparrow and 1 Northern Waterthrush turned up in the nets this season. Raptor counts produced 2 Swainson’s Hawks, the 1st for RPBO having been witnessed in the spring of 2000. A Short Eared Owl spotted in October was only the 2nd record for RPBO. David Allinson observed an Emperor Goose flying near Bentinck Island which constituted the 2nd record for this species, the first being a historical record for Race Rocks. A northern Pygmy Owl was observed near the commissionaire’s gate (outside of the count area). The first fall record of a White Winged Crossbill was a highlight. Nashville Warbler is a species that was nearly annual at Rocky Point but hasn’t been seen since 1997. Table 4 is a detailed list of unusual observations this fall.
Table 4. Unusual observations.
|
Red Throated Loon: 1 off Cape Calver on Sept 9.(DEA) |
Jaeger Sp. 2 on September 6 (KE). 1 on Sept 17 (MAS) |
|
Pied Billed Grebe: 1 on September 8 which stayed until the 15th of Sept.(DGD) |
Little Gull: 1 on Sept 9(DEA) |
|
Northern Fulmar: 1 observed off Cape Calver while conducting seawatch on August 20. (DEA) |
Ring Billed Gull: A very good year for this species with 10 records. An impressive 5 on Sept 10. |
|
Sooty Shearwater: A record low 1 individual observed for the fall was seen on August 20. (DEA) |
Herring Gull: 3 on September 3(DEA) .2 on September 5 (KE) and 1 on Oct 15.(DEA) |
| Brown Pelican: Only 1 on Oct 17.(COB) |
Western Gull: a singleton on August 3 is early. (DGD, AKD) |
| Turkey Vulture: 350 on September 20 | Sabine's Gull: 4 on Sept 30 (DEA). |
|
Greater White Fronted Goose: 1100 on Sept 30 was impressive. (MSM,DGD,DEA) |
Glaucous Gull: 1 on Oct 15 (DEA) was a 1st for RPBO. |
|
Emperor Goose: 1 seen flying with Canadas at Bentinck Island is the 2nd record for RPBO.(DEA) |
Caspian Tern: 1 on July 29 (DEA) and another on July 28 (DEA). |
|
Wood Duck: A single flushed out of lower ponds on August 12 (KB, DGD). Another on August 29 (SMB). A female on September 5.(KE) |
Common Tern: Extremely scarce this year, 2 on July 29, and 1 on September 9 comprise the first and last records for the fall. A season high of only 11 was reached on August 18. |
|
Ring Necked Duck: 1 found on census in the Upper Ponds on September 23 (RJS). |
Cassin's Auklet: 1 on August 19 (DEA) 1 on September 9. 2 on September 25 (DGD). |
|
Black Scoter: 2 on September 27 (PHG) and 2 on October 8.(DEA) |
Tufted Puffin: 1 spotted off Edye Point on September 9.(DEA) |
|
Broad Winged Hawk: 27 records for the fall. A maximum of 6 on October 10. (MSM) |
Mourning Dove: 1 on September 11 (DGD,GCG) and 1 on September 30. (PHG) |
|
Swainson's Hawk: 1 on September 4 and another on October 1.(DEA) |
Short Eared Owl: 1 at dusk in the upper field on October 6 is only the 2nd record for RPBO. (DGD) |
|
Rough Legged Hawk: 1 on October 7 (DEA) and 3 on October 10.(MSM) |
Dusky Flycatcher: 1 captured and banded from net 7 on September 5 is the 2nd of this species ever banded at RPBO.(DGD,GCG,KE) |
|
Golden Eagle: 1 on October 3 and 2 on October 14. |
Northern Shrike: Only a single on September 24. (DEA) |
|
Sandhill Crane: 2 fly overs on September 2 (mobs).4 in the afternoon of September 13.(DGD) |
Tree Swallow: 1 on August 8 at the Upper Ponds.(DGD) |
|
Solitary Sandpiper: 1 on September 8 (COB). |
Townsend's Solitaire: 2 on September 15 flying with migrating robins.(DGD) |
|
Spotted Sandpiper: 1 on August 15, 3 on September 4.1 on September 9, 1 on 12th. |
Western Palm Warbler: 1 on September 24. (DEA) |
|
Whimbrel: 3 on July 30 was a season high. (mobs) |
Blackpoll Warbler: 1 on September 3rd at Cape Calver was the 1st record of this species for RPBO. (DEA) |
|
Western Sandpiper: Season high of 128 on August 27. (mobs.) |
Northern Waterthrush: 1 banded on Sept 25.(GCG,MJP) |
|
Baird's Sandpiper: 1 on Sept 2 (DEA, DGD), 2 on September 3rd.(DEA) |
Lincoln's Sparrow: 1 found singing on Census on July 23 (MAS) and 2 individuals on July 25(DEA) constitute record early sightings. |
| Pectoral Sandpiper: 1 on August 12. |
White Throated Sparrow: 1 banded on Oct 4 and another banded on Oct 12.(DGD,RFM, MJP) |
|
Red Necked Phalarope: 480 on September 3rd. (DEA) |
Lapland Longspur: a single on Sept 30.(DEA) |
| Red Phalarope: 5 on September 3. (DEA) | Yellow Headed Blackbird: 1 on Oct 8.(DEA) |
|
Parasitic Jaeger: 1 on August 31(GCG), 1 on September 4. (DEA). 1 on Sept 30. |
White Winged Crossbill: 1 fly over on Oct 7. (DGD) |
Table 5. Key to list of Observers.
| AKD | Andy Davis | KB | Ken Burton | RFM | Rod Mitchell |
| COB | Colleen O'Brien | KE | Kyle Elliot | RJS | Rick Schortinghuis |
| DEA | David Allinson | MAS | Mike Setterington | SMB | Suzanne Beauchesne |
| DGD | Daniel Derbyshire | MJP | Michael Porter | mobs. | Many Observers |
| DJA | Devon Anderson | MSM | Susanne Maidment | ||
| GCG | Graeme Gibson | PHG | Pierre Geoffrey |
Data used for the following analysis pertains to fall migration monitoring only, specifically the period of July 15-October 25. The following analysis covers years 1994-2000 (excluding 1998), although focusing heavily on 1999 and 2000. It should be mentioned that there are considerable differences between years in terms of the number of nets used and the number of total net hours. 1994 was a pilot year, and several different net configurations were used. The net set-up remained in a constant state of flux until 1998 when net locations were standardized (net numbers 1-10). Furthermore, in years 94-97, banding effort was not conducted on a daily basis but rather sporadically. Therefore, it is hereby stressed that the banding totals for years 1994-1997 are based on seasons consisting of approximately 45 days worth of coverage as opposed to 90 days for 1999 and 2000. Inferences can be made when comparing year 2000 to 1996 for example when considering the fact that there is such a marked difference in the amount of banding effort (approx. 50%).
Net configuration and net hours are consistent for years 1999 and 2000. The following Table (Table 6) is instructive for several species. Species showing significant changes between years include: Sora, Pileated Woodpecker, Stellar’s Jay, Chestnut Backed Chickadee, Ruby Crowned Kinglet, Hermit Thrush, Swainson’s Thrush, Wilson’s Warbler, Yellow Rumped Warbler, Common Yellowthroat, Savannah Sparrow, Lincoln’s Sparrow, White Crowned Sparrow, Golden Crowned Sparrow, and American Goldfinch. Only Wilson’s Warbler demonstrates a higher capture rate, while the other species may indicate that either they are now less common than they were in previous years or that the protocol (i.e. number of nets or net locations) used to collect earlier data differs widely from the current method. Hermit Thrush, Swainson’s Thrush, Savannah Sparrow, Lincoln’s Sparrow and Golden Crowned Sparrow show very high numbers in 94-97 as compared to 99 and 2000 based on the amount of netting effort for those years (50% of 99-2000). Therefore, these differences between years may be reflective of changes in banding protocol, changes in habitat (e.g. die back of broom) or fluctuations in numbers of birds using the site.
Table 6: Total number banded each season for years 1994-2000 (excludes 1998). Columns for 2000 display totals for nets 1-10 (standard setup) and nets 1-13.
|
Species
|
2000 (nets 1-10) |
2000 (nets 1-13) |
1999 | 1997 | 1996 | 1995 | 1994 |
1994-2000 |
| Northern Harrier | 2 | 2 | ||||||
| Cooper's Hawk | 1 | 1 | ||||||
| Sharp-shinned Hawk | 1 | 1 | 2 | 2 | 4 | 1 | 3 | 13 |
| Virginia Rail | 1 | 1 | ||||||
| Sora | 1 | 2 | 1 | 4 | ||||
| Semipalmated Sandpiper | 1 | 1 | ||||||
| Western Sandpiper | 12 | 12 | ||||||
| Northern Saw-whet Owl | 2 | 2 | 1 | 3 | 3 | 2 | 11 | |
| Common Nighthawk | 1 | 1 | ||||||
| Downy Woodpecker | 1 | 2 | 1 | 1 | 2 | 7 | ||
| Hairy Woodpecker | 1 | 1 | 2 | 3 | ||||
| Northern Flicker | 2 | 3 | 1 | 4 | ||||
| Pileated Woodpecker | 2 | 1 | 2 | 5 | ||||
| Olive-sided Flycatcher | ||||||||
| Western Wood-pewee | 1 | 1 | 1 | 3 | 5 | |||
| Willow Flycatcher | 19 | 24 | 35 | 8 | 13 | 6 | 11 | 94 |
| Pacific-slope Flycatcher | 133 | 228 | 228 | 91 | 54 | 79 | 52 | 732 |
| Hammond's Flycatcher | 18 | 31 | 15 | 9 | 15 | 10 | 12 | 90 |
| Dusky Flycatcher | 1 | 1 | 1 | 2 | ||||
| Northern Shrike | 1 | 1 | ||||||
| Hutton's Vireo | 6 | 8 | 1 | 2 | 1 | 2 | 4 | 18 |
| Warbling Vireo | 11 | 13 | 17 | 2 | 10 | 9 | 6 | 57 |
| Cassin's Vireo | 4 | 4 | 3 | 2 | 1 | 10 | ||
| Stellar's Jay | 4 | 5 | 2 | 1 | 9 | 31 | 48 | |
| Violet-green Swallow | 4 | 4 | 5 | 9 | ||||
| Northern Rough-winged Swallow | 4 | 4 | 7 | 3 | 14 | |||
| Barn Swallow | 4 | 4 | 2 | 4 | 10 | |||
| Chestnut-backed Chickadee | 36 | 69 | 50 | 56 | 43 | 33 | 49 | 300 |
| Red-breasted Nuthatch | 2 | 5 | 1 | 2 | 1 | 9 | ||
| Bushtit | 18 | 39 | 50 | 15 | 19 | 48 | 171 | |
| Brown Creeper | 10 | 11 | 7 | 10 | 7 | 6 | 5 | 46 |
| Bewick's Wren | 25 | 45 | 33 | 9 | 15 | 17 | 16 | 135 |
| House Wren | 3 | 9 | 6 | 2 | 4 | 3 | 1 | 25 |
| Winter Wren | 213 | 265 | 61 | 102 | 106 | 64 | 75 | 673 |
| Marsh Wren | 19 | 19 | 4 | 1 | 4 | 6 | 6 | 40 |
| Golden-crowned Kinglet | 46 | 81 | 57 | 37 | 25 | 10 | 26 | 236 |
| Ruby-crowned Kinglet | 219 | 295 | 199 | 159 | 232 | 79 | 70 | 1034 |
| American Robin | 12 | 17 | 10 | 8 | 1 | 11 | 11 | 58 |
| Hermit Thrush | 38 | 52 | 37 | 96 | 84 | 54 | 18 | 341 |
| Swainson's Thrush | 32 | 47 | 9 | 67 | 41 | 25 | 16 | 205 |
| Varied Thrush | 1 | 2 | 2 | 4 | 9 | |||
| European Starling | 1 | 1 | 1 | 2 | ||||
| Cedar Waxwing | 1 | 2 | 3 | |||||
| Orange-crowned Warbler | 90 | 125 | 185 | 109 | 82 | 66 | 66 | 633 |
| Nashville Warbler | 2 | 1 | 3 | |||||
| Yellow Warbler | 120 | 139 | 106 | 101 | 38 | 45 | 44 | 473 |
| Yellow-rumped Warbler | 19 | 19 | 23 | 32 | 39 | 37 | 9 | 159 |
| Black-throated Gray Warbler | 1 | 5 | 3 | 3 | 2 | 4 | 17 | |
| Townsend's Warbler | 2 | 4 | 4 | 1 | 3 | 2 | 14 | |
| American Redstart | 1 | 1 | ||||||
| Northern Waterthrush | 1 | 1 | 1 | 2 | 2 | 6 | ||
| Mourning Warbler | 1 | 1 | ||||||
| MacGillivray's Warbler | 30 | 43 | 32 | 19 | 9 | 18 | 14 | 135 |
| Common Yellowthroat | 54 | 58 | 60 | 66 | 59 | 53 | 79 | 375 |
| Wilson's Warbler | 140 | 177 | 257 | 53 | 37 | 58 | 70 | 652 |
| Western Tanager | 1 | 1 | 1 | 2 | ||||
| Black-headed Grosbeak | 2 | 2 | 1 | 2 | 5 | |||
| Lazuli Bunting | 1 | 1 | ||||||
| Spotted Towhee | 75 | 100 | 49 | 51 | 48 | 21 | 44 | 313 |
| Chipping Sparrow | 13 | 13 | 12 | 3 | 9 | 8 | 45 | |
| Savannah Sparrow | 115 | 115 | 111 | 132 | 123 | 97 | 105 | 683 |
| Fox Sparrow | 63 | 79 | 40 | 50 | 59 | 31 | 29 | 288 |
| Song Sparrow | 87 | 120 | 71 | 114 | 63 | 79 | 134 | 581 |
| Lincoln's Sparrow | 168 | 171 | 154 | 138 | 120 | 124 | 151 | 858 |
| Swamp Sparrow | 1 | 1 | 3 | 5 | ||||
| White-crowned Sparrow | 56 | 57 | 23 | 42 | 53 | 36 | 72 | 283 |
| Golden Crowned Sparrow | 20 | 23 | 25 | 105 | 63 | 28 | 56 | 300 |
| White-throated Sparrow | 2 | 2 | 1 | 1 | 7 | 2 | 13 | |
| Oregon Junco | 70 | 88 | 72 | 62 | 37 | 30 | 52 | 341 |
| Lapland Longspur | 1 | 1 | ||||||
| Bobolink | 1 | 1 | ||||||
| Red-winged Blackbird | 17 | 17 | 16 | 1 | 1 | 8 | 43 | |
| Brown-headed Cowbird | 20 | 21 | 8 | 6 | 2 | 1 | 6 | 44 |
| Purple Finch | 6 | 7 | 13 | 2 | 1 | 6 | 3 | 32 |
| House Finch | 1 | 1 | 1 | 2 | 4 | |||
| Pine Siskin | 51 | 4 | 10 | 5 | 70 | |||
| American Goldfinch | 45 | 45 | 68 | 46 | 39 | 42 | 90 | 330 |
| House Sparrow | 1 | 1 | ||||||
| "Slate-coloured Junco" | 1 | 1 | ||||||
| "Unidentified Dark Eyed Junco" | 13 | 13 | ||||||
| "Hybrid Passerine" | ||||||||
| Total number of Individuals | 2107 | 2723 | 2255 | 1818 | 1571 | 1260 | 1547 | 11169 |
| Total number of species | 56 | 57 | 61 | 52 | 54 | 62 | 60 |
* Underlined totals represent record high banding totals in 2000 for given species. (for nets 1-10 only)
Banding totals for year 2000 (nets 1-10) show a marked increase for Winter Wren and Spotted Towhee. Orange Crowned Warbler, Pacific Slope Flycatcher and Wilson’s Warbler were captured in much lower numbers this year. It would appear from numbers of these species captured in earlier years that 1999 was an exceptional year for OCWA, PSFL, and WIWA while 2000 was an exceptional year for WIWR and SPTO. The nets also failed to produce a single Pine Siskin. Siskins and Crossbills were in short supply all season, possibly reflecting irruptions in cone crop. Fall 2000 was also a record year for Brown Headed Cowbirds banded (more than double of that banded in any other year). Fledgling Cowbirds were seen in July and August being fed by Pacific Slope Flycatchers, Wilson's and Orange Crowned Warblers, Chipping and White Crowned Sparrows and Chestnut Backed Chickadee’s! To the author’s knowledge this has not been encountered as much in the past. Cowbird Parasitism at Rocky Point should be closely monitored in the future.
A substantial amount of variation between years in the rankings of most commonly banded species at Rocky Point.(Table 7) Note that rankings for 2000 change dramatically when captures from nets 11-13 are subtracted. Ruby Crowned Kinglet, Lincoln’s Sparrow and Savannah Sparrow have consistently ranked high in each season, although both sparrow species are showing lower rankings over recent years.
Table 7. Top 15 Species banded for 1994-2000.
| 2000 | Species |
Net setup |
1999 |
1997 |
1996 |
1995 |
1994 |
||||||
| Rank |
1-10 |
1-13 |
No. |
Rnk. |
No. |
Rnk. |
No. |
Rnk. |
No. |
Rnk. |
No. |
Rnk. |
|
|
1 |
RCKI |
219 |
295 |
199 |
3 |
159 |
1 |
232 |
1 |
79 |
3 |
70 |
8 |
|
2 |
WIWR |
213 |
265 |
61 |
10 |
102 |
7 |
106 |
4 |
64 |
5 |
75 |
6 |
|
5 |
PSFL |
133 |
228 |
228 |
2 |
91 |
10 |
54 |
9 |
79 |
3 |
52 |
11 |
|
4 |
WIWA |
140 |
177 |
257 |
1 |
53 |
15 |
37 |
- |
58 |
6 |
70 |
8 |
|
3 |
LISP |
168 |
171 |
154 |
5 |
138 |
2 |
120 |
3 |
124 |
1 |
151 |
1 |
|
6 |
YWAR |
120 |
139 |
106 |
7 |
101 |
8 |
38 |
15 |
45 |
9 |
44 |
14 |
|
8 |
OCWA |
90 |
125 |
185 |
4 |
109 |
5 |
82 |
6 |
67 |
4 |
66 |
9 |
|
9 |
SOSP |
87 |
120 |
71 |
8 |
114 |
4 |
63 |
7 |
79 |
3 |
134 |
2 |
|
7 |
SAVS |
115 |
115 |
111 |
6 |
132 |
3 |
123 |
2 |
97 |
2 |
105 |
3 |
|
10 |
SPTO |
75 |
100 |
49 |
13 |
51 |
- |
48 |
11 |
21 |
- |
44 |
14 |
|
11 |
ORJU |
70 |
88 |
72 |
9 |
62 |
13 |
37 |
- |
30 |
15 |
52 |
11 |
|
12 |
FOSP |
63 |
79 |
40 |
15 |
50 |
- |
59 |
8 |
31 |
14 |
29 |
- |
|
13 |
COYE |
54 |
58 |
60 |
11 |
66 |
12 |
59 |
8 |
53 |
8 |
79 |
5 |
|
14 |
GCKI |
46 |
81 |
57 |
12 |
37 |
- |
25 |
- |
10 |
- |
26 |
- |
|
15 |
CBCH |
36 |
69 |
50 |
14 |
56 |
14 |
43 |
12 |
33 |
13 |
49 |
12 |
When looking at the data according to monthly periods, 1999 and 2000 are quite similar (See Tables 8 and 9). The number banded for 2000 includes birds captured from nets 11-13. Table 6 shows comparisons for nets 1-10 only. Therefore, by comparing the capture rates by month, the impact of the new nets can be correlated to specific time periods. Table 8 indicates that capture rates for nets 1-13 were lower in July/August than with only 10 nets in 1999. This is consistent with lower banding totals for typical August species such as Pacific Slope Flycatcher and Wilson’ Warbler this year. As expected, increases in capture rates with the new nets were indicated for September and October. Remarkably, the overall or season captures/net hour figures for nets 1-10 are identical in both 99 and 2000.
Table 8: Monthly banding totals for 1999-2000 showing comparisons for nets 1-10 vs. 1-13.
|
Total number of Captures |
Total net hours |
Captures/net hour |
||||
|
1-10 |
1-13 |
1-10 |
1-13 |
1-10 |
1-13 |
|
| Year |
1999 |
2000 |
1999 |
2000 |
1999 |
2000 |
| July/August |
1050 |
1053 |
2177 |
2505 |
.48 |
.42 |
| September |
719 |
1028 |
1408 |
1549 |
.51 |
.66 |
| October |
403 |
643 |
908 |
1059 |
.44 |
.61 |
| total |
2172 |
2724 |
4493 |
5113 |
.48 |
.53 |
Table 9. Monthly banding totals for 1999-2000 showing comparisons for nets 1-10.
|
Total number of Captures |
Total net hours |
Captures/net hour |
||||
|
1-10 |
1-10 |
1-10 |
1-10 |
1-10 |
1-10 |
|
| Year |
1999 |
2000 |
1999 |
2000 |
1999 |
2000 |
| July/August |
1050 |
776 |
2177 |
2151 |
.48 |
.36 |
| September |
719 |
827 |
1408 |
1346 |
.51 |
.61 |
| October |
403 |
502 |
908 |
923 |
.44 |
.54 |
| total |
2172 |
2105 |
4493 |
4420.0 |
.48 |
.48 |
Capture rates for nets 1-10 (Table 9) when compared to 1999 indicate no change as captures/net hour in 1999 and 2000 for nets 1-10 was .48. 1999 had a high capture rate in July/August while 2000 featured very low rates in this period. It was busier at the nets in September and October for 2000 as compared to 1999. Historically September has been the busiest period of the season, however this has not decisively been the case in recent years. Although total net hours have been low in September for 1999 and 2000 (largely due to weather and military activity), the capture/net hour figures should be higher. It would be helpful to have information of this sort for earlier years in order to determine whether this is unusual. My impression based on decreases in captures of sparrows, thrushes and Orange Crowned Warblers in 1999 and 2000 is that September capture rates are lower than normal.
Having the recapture data entered electronically, we are now able to quickly look up retrap records. A Red Shafted Flicker recaptured at net 11 in July 2000 was originally banded in spring of 1995 by Mike Shepard. The Pacific Slope Flycatcher represents an unusual recapture record as this species is rarely recaptured in the same month of original banding let alone a year later. The Bushtit retrap represents an interesting longevity record for this species. Rather amazing was a 4 year old Fox Sparrow banded on September 26, 1996 and recaptured on September 26, 2000. The difference between records is exactly 4 years and 55 minutes! A Lincoln's Sparrow also demonstrated some remarkable timing in migration between 1999 and 2000, showing up this season only a day later than last year. There were several recaptures of birds originally banded in 1998, however this data has not yet been entered onto computer. It appears that most of the local breeding Wilson's Warbler, Orange Crowned Warbler and Common Yellowthroat from the "early years" did not return this past spring and early summer.
Table 10. Selected recaptures of interest.
|
Species |
Band Number |
Date Banded |
Date of Recapture |
Age when banded |
|
|
Red Shafted Flicker |
1453-30160 |
May 8 1995 |
July 26 2000 |
AHY |
|
|
Pacific Slope Flycatcher |
2130-35356 |
July 25 1999 |
July 16 2000 |
AHY |
|
|
Chestnut Backed Chickadee |
2120-06883 |
Aug 2 1997 |
Sept 14 2000 |
HY |
|
|
Bushtit |
2100-58628 |
Aug 8 1998 |
Aug 3 2000 |
U |
|
|
Ruby Crowned Kinglet |
2130-34524 |
Oct 4 1999 |
Oct 12 2000 |
HY |
|
|
Swainson's Thrush |
1461-34286 |
July 21 1998 |
July 23 2000 |
AHY |
|
|
Spotted Towhee |
1142-47183 |
Oct 2 1999 |
Oct 7 2000 |
HY |
|
|
Spotted Towhee |
1142-47187 |
Oct 3 1999 |
Oct 7 2000 |
AHY |
|
|
Fox Sparrow |
8051-65033 |
Sept 26 1996 |
Sept 26 2000 |
HY |
|
|
Song Sparrow |
1461-34039 |
Aug 20 1997 |
Oct 3 2000 |
HY |
|
|
Lincoln's Sparrow |
2161-15441 |
Sept 12 1999 |
Sept 13 2000 |
HY |
|
5. NET SETUP ANALYSIS
Three additional nets were added in July 2000 to attempt to capture more birds and to capture species not adequately represented by the existing nets. This section assesses the productivity of nets 11-13. The "back nets" 11-13 are located in the "tunnel" area of the census route which is situated in an open area surrounded by Douglas and Grand Fir. Net cover consists of Alder, Garry Oak, Salmon Berry and rose bushes. It was immediately apparent that the new nets were very productive, although they weren’t as productive for species not commonly captured in nets 1-10 as we had hoped. Table 11 shows the captures/net hour for each net. The most productive net was number 11 followed by numbers 13, 7, and 12. Nets 11-13 caught 23% of the season banding total, which is instructive, as these nets were operational only on alternate days as reflected in the total net hours.
Table 11. Net Capture results 2000.
| Net # |
Individuals captured |
Capture percentage |
No. of net hours |
Captures per. net hour |
| 1 |
105 |
3.9% |
370.99 |
.28 |
| 2 |
197 |
7.3% |
370.99 |
.53 |
| 3 |
263 |
9.8% |
445.83 |
.59 |
| 4 |
237 |
8.9% |
461.08 |
.51 |
| 5 |
120 |
4.5% |
462.08 |
.26 |
| 6 |
187 |
7.0% |
462.33 |
.40 |
| 7 |
392 |
14.7% |
462.33 |
.84 |
| 8 |
74 |
2.8% |
461.13 |
.16 |
| 9 |
275 |
10.3% |
461.33 |
.60 |
| 10 |
195 |
7.3% |
462.00 |
.42 |
| 11 |
243 |
9.1% |
231.58 |
1.05 |
| 12 |
150 |
5.6% |
231.58 |
.65 |
| 13 |
227 |
8.5% |
230.58 |
.98 |
| Total |
2665 |
99.7 |
5113.83 |
.52 |
Table 12 lists the species and their total number captured from nets 11-13. Species showing a high degree of representation (>40%) from the "back nets" include: Downy Woodpecker, Hammond's Flycatcher, Chestnut Backed Chickadee, Red Breasted Nuthatch, Bushtit, Bewick’s Wren, House Wren, Golden Crowned Kinglet, Black Throated Grey Warbler, and Townsend's Warbler. It is significant that 80% of BTYW and 50% of TOWA were captured in the new nets as these have been difficult species to catch and are species of concern for RPBO.
Table 12. Nets 11-13 summary.
|
Species |
No. of birds nets 11-13 |
No. of birds: 1-13 |
% of BN total from all nets |
|
| 1 | Downy Woodpecker |
1 |
1 |
100 |
| 2 | Northern Flicker |
1 |
3 |
33 |
| 3 | Willow Flycatcher |
5 |
24 |
20 |
| 4 | Pacific Slope Flycatcher |
95 |
228 |
41 |
| 5 | Hammond's Flycatcher |
13 |
31 |
41 |
| 6 | Hutton's Vireo |
2 |
8 |
25 |
| 7 | Warbling Vireo |
2 |
13 |
15 |
| 8 | Stellar's Jay |
1 |
5 |
20 |
| 9 | Chestnut Backed Chickadee |
33 |
69 |
47 |
| 10 | Red Breasted Nuthatch |
3 |
5 |
60 |
| 11 | Bushtit |
21 |
39 |
53 |
| 12 | Brown Creeper |
1 |
11 |
9 |
| 13 | Bewick's Wren |
20 |
45 |
44 |
| 14 | House Wren |
6 |
9 |
66 |
| 15 | Winter Wren |
52 |
265 |
19 |
| 16 | Golden Crowned Kinglet |
35 |
81 |
43 |
| 17 | Ruby Crowned Kinglet |
76 |
295 |
25 |
| 18 | American Robin |
5 |
17 |
29 |
| 19 | Hermit Thrush |
14 |
52 |
26 |
| 20 | Swainson's Thrush |
15 |
47 |
31 |
| 21 | Orange Crowned Warbler |
35 |
125 |
28 |
| 22 | Yellow Warbler |
19 |
139 |
13 |
| 23 | Black Throated GrayWarbler |
4 |
5 |
80 |
| 24 | Townsend's Warbler |
2 |
4 |
50 |
| 25 | MacGillivray's Warbler |
13 |
43 |
30 |
| 26 | Common Yellowthroat |
4 |
58 |
6 |
| 27 | Wilson's Warbler |
37 |
177 |
20 |
| 28 | Spotted Towhee |
25 |
100 |
25 |
| 29 | Fox Sparrow |
16 |
79 |
20 |
| 30 | Song Sparrow |
33 |
120 |
27 |
| 31 | Lincoln's Sparrow |
3 |
171 |
1 |
| 32 | White Crowned Sparrow |
1 |
57 |
13 |
| 33 | Golden Crowned Sparrow |
3 |
23 |
13 |
| 34 | Oregon Junco |
18 |
88 |
20 |
| 35 | Brown Headed Cowbird |
1 |
21 |
4 |
| 36 | Purple Finch |
1 |
7 |
14 |
*Numbers in bold represent species with high representation from nets 11-13 (40% or greater).
The average capture/net hour for nets 11-13 was .89, which compared to the average for 1-10 at .46 birds/net hour, is quite high. Therefore, nets 11-13 were quite successful and their "phase in" should be continued into fall 2001. Based on these numbers, we can assume that banding at Rocky Point in 2002 will be a much busier affair when nets 11-13 are run every day.
Table 13. Nets 11-13 summation
| Net # | total number of individuals |
% of season total |
total net hours |
captures/ net hour |
Species total |
|||||
| 11 |
243 |
9.1% |
231.58 |
1.05 |
NA |
|||||
| 12 |
150 |
5.6% |
231.58 |
.65 |
NA |
|||||
| 13 |
227 |
8.5% |
230.58 |
.98 |
NA |
|||||
| Total |
620 |
23% |
693.74 |
.89 |
36 |
|||||
| 1-10 |
2045 |
77% |
4420.09 |
.46 |
56 |
|||||
The productivity of the standard set-up (nets 1-10) between 1999 and 2000 (see Table 14) demonstrates very close capture/net hour percentages with a slight drop in species diversity shown in 2000. Unfortunately, specific net capture percentages are not available for 1999 as net numbers were not recorded on the banding sheets. It would be helpful to compare the capture rates for each net from 1994-2000 to detect any changes in sheer numbers and species represented.
Table 14: Nets 1-10 summation 1999 vs. 2000.
| Year | Tot. net hours | Total captures | Captures/ net hour | Species Total | |
| Nets 1-10 | 1999 | 4493.48 | 2255 | .50 | 61 |
| 2000 | 4420.09 | 2045 | .46 | 56 | |
| Average | 4433.545 | 2150 | .48 | 58.5 | |
| Nets 11-13 | 2000 | 693.74 | 620 | .89 | 36 |
6. COVERAGE
Coverage at Rocky Point in 2000 was very good as only 1 day out of 91 planned days of coverage was completely lost due to DND activities on Bentinck Island. Even more impressive, given the nature of weather on the west coast in September and October, is that only 2 days of banding were completely rained out. There was a 5 day stretch in September (11th-15th) where coverage was light due to DND demolition's. Census and some banding were conducted during this week. It is hoped that the number of "blasting days" on Bentinck Island remains the same in future years, as we can ill afford to lose any more coverage. Particularly problematic for standardization and consistency is having a number of "blasting days" in a row, which creates a large hole in the continuity of the data.
Table 15. Selected Coverage statistics.
|
Coverage |
2000 |
| Days during 90-day target period with: | |
| Coverage |
90 |
| Census and ET's |
90 |
| No banding due to weather |
2 |
| No banding due to DND demolitions |
4 |
| Some banding lost due to weather |
30 |
| Some banding lost due to DND |
4 |
| Percentage of banding lost due to weather |
13% |
| Percentage of banding lost due DND demo. |
7% |
| Number of volunteers |
38 |
| Total volunteer days |
255 |
7. PERSONNEL
Migration monitoring at Rocky Point hinges upon having a solid group of dedicated volunteers and this season was efficient and enjoyable as a result of their efforts. In fall 2000, 38 volunteers contributed 255 volunteer days. Volunteers were primarily from Victoria, although we had travelers from as far away as Ontario, Powell River, Delta, Okanogan and Queen Charlotte Islands. All volunteers are deeply thanked for their effort. The author would especially like to thank Graeme Gibson, David Allinson, Michael Porter and Rod Mitchell for their tireless support.
Table 16. List of volunteers with volunteer effort.
|
Days |
Volunteers |
|
15-30 |
David Allinson, Devon Anderson, Graeme Gibson, Susanne Maidment, Colleen O'Brien and Rick Schortinghuis. |
|
6-14 |
Suzanne Beauchesne, Pierre Geoffrey, Bev Glover, Paul Levesque, Rod Mitchell, Michael Porter, Claudia Riveros, Mike Setterington and Hank Vanderpol |
|
1-7 |
Gail Austin, Darrin Bennett, Rosaline Canessa, Dannie Carson, Gabriel David, Kyle Elliot, Jim Flizcuk, Colin French, Bryan Gates, Tom Gillespie, Robert Hadley, Don & Marianne Johnson, Linda Knox, Marilyn Lambert, Diane & Jason Leblanc, Cheryl Mackie, Sheila Mosher, Anne Nightingale, Laurie Savard, Germaine Taylor, Harlan Wright and Arlene Yaworski. |
8. RECENT DEVELOPMENTS
Many improvements were made in fall 2000, which have enhanced the efficiency of the operation. As stated earlier in this report, three additional nets were added to the standard compliment of 10 nets in July. These nets proved to be very productive in terms of volume of birds captured and diversity of species represented. (see section 4) These "back nets" were opened when possible every other day in order to phase them in over a 2 year period, after which they will be run every day. This was necessary to account for the impact of the additional nets on the estimated totals.
The banding shelter was made larger and strengthened, a large banding table was fitted, cabinets were built for storage purposes and the roof was repaired to shield the rain. This upgrade was greatly appreciated by staff and volunteers.
Protocol versions 1.2 and 1.3 were written which adjusted procedures for migration monitoring at Rocky Point. A new count area was flagged for fall 2001 when the old count area will be replaced. This was done because it was felt that the existing count area was too large to be covered appropriately and therefore is subject to day to day variability within the general observations. It is yet to be determined whether the effects of this change are significant enough to force the use of two protocols for fall 2001.
The retrap system was overhauled and the ET data sheets and daily log sheets were revised. Retrap records for 1999 and 2000 were entered by hand onto 4x6 index cards to facilitate faster and more efficient r