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RESPONDENT
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Richard Lanctot
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SITE NAME
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Barrow, Alaska, USA
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| Contact details
(phone/fax//e-mail//address): |
| 907-786-3609/907-786-3641(f) // richard_lanctot@fws.gov // USFWS, 1011 E. Tudor Road, MS 201 Anchorage, AK 99503, USA
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PROJECT DETAILS |
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Project name:
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Barrow, Alaska, Shorebird Study
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Start of survey:
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End
of survey: |
Team
size: |
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01.06
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01.09
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4
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WEATHER
CONDITIONS
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Weather conditions: |
| The spring and summer was warmer than 2003 but colder than 2004. The snow melt was later than in 2003 or 2004, however. No severe winter storm took place during the field season. Weather data available from NOAA weather station located near Barrow.
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| Date of 50%
snow-cover: |
12.06
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| Date of ice-break on
rivers: |
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| Date of final loss of
snow: |
22.06
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BIOTIC
CONDITIONS
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| Rodents abundance evaluation: |
average
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Breeding conditions:
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This report represents the conclusion of three years of intensive breeding ecology work on shorebirds at Barrow. Relative to 2003 and 2004, the 2005 season appeared to be warmer than 2003 but colder than 2004. The snow melt was fairly late in 2005, especially in some of the low lying plots, but overall the summer temperatures appeared to be about average. There were also more Snowy Owls attempting to nest in the area, which is thought to reflect lemming availability. Hatching success of shorebird nests was extremely high in 2005, compared to the dismal levels observed in 2004. This is most likely because Arctic Foxes were removed (killed) from the study area as part of a Steller's Eider Recovery Management Action. We had one new species nesting on our plots in 2005: the Baird Sandpiper. We did not detect Buff-breasted Sandpipers, White-rumped Sandpipers or Western Sandpipers nesting in or near our study plots in 2005 (in contrast to finding 1-2 nests/species in 2004). Renesting by shorebirds was minimal to non-existent in 2005.
The nest density of all shorebird species on our plots (controlling for number of plots) was 52.1/km2 in 2003, 66.6 in 2004, and 63.0 in 2005 (overall average density across years was 60.6). Although we thought the unusually high density of nests in 2004 (especially when compared to 2003) was due to high predation and thus a high rate of renesting, we had a similar density levels in 2005 as 2004. We believe the high densities in 2005 may be due to a fox removal program that allowed many nests to survive through to hatching (see below), and in effect, gave us more time to find the nests. Thus, we believe the density of nests from 2005 may be our best estimate of the number of pairs initiating nests calculated to date.
The species assemblage in Barrow has consistently included good numbers of Red Phalarope (REPH, 3-year average density = 25.9 nest/km2), Dunlin (DUNL, 13.3), Pectoral Sandpiper (PESA, 11.5), and Semi-palmated Sandpiper (SESA, 5.2). Only a few nests are discovered each year belonging to American Golden-plover (AMGP, 1.2), Long-billed Dowitcher (LBDO, 1.9) and Red-necked Phalarope (RNPH, 0.9). Three other species have only been documented nesting on our tundra plots in one year (Western Sandpiper, WESA; White-rumped Sandpiper, WRSA; and Baird's Sandpiper, BASA). Pectoral Sandpiper densities are known to increase and decrease dramatically across years, and 2005 appeared to be an especially high year. A total of 136 nests were located on our plots, including 43 PESA, 38 REPH, 31 DUNL, 15 SESA, 5 LBDO, 2 RNPH, and 1 AMGP. In addition we located our first Baird's Sandpiper (BASA) on the tundra plots, near disturbed habitat in the new landfill. This species regularly breeds on the gravel areas near the Barrow Arctic Science Consortium housing.
The first shorebird clutch was initiated on 3 June and the last on the 4 July in 2005 (on or within 1 day for both dates in prior years). Median and peak initiation dates were the 13 and 10 June, respectively; the median was a few days earlier and the peak was nearly a week earlier than prior years. Median nest initiation dates for the more abundant species was the 10 June (DUNL, SESA), 14 June (REPH), and the 15 June (PESA). This pattern is similar to prior years for the more abundant species, whereas the rest of the species vary tremendously from year-to-year. Predators destroyed only 11.2% of the nests in 2005 compared to 42.6% in 2003 and 67.9% in 2004. A comparison of nesting success across the more abundant species indicated hatching success (# hatching at least one young/total number of nests) was highest in PESA (86.4%, N = 59), followed by DUNL (76.1%, N = 56), SESA (72.7%, N = 23), and REPH (70.2%, N = 62). A similar comparison across study plots indicated plots 1, 2, and 3 had extremely high hatching success (73.9, 66.6, and 88.8%, respectively) compared to that reported in 2003 (52.6, 46.2 and 38.8%) and 2004 (3.2, 4.2, and 11.1%). The two plots established in 2004 also had higher hatching success in 2005 (85.7 versus 11.1, and 75.6 versus 20.5%). These extremely high hatching success rates are likely due to the removal of Arctic Foxes in the Barrow area by contractors paid through the Steller's Eider Research Team.
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Rodent dynamics:
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Lemming numbers were up in 2005 from 2003 and 2004, but were not superabundant. No capture data. Brown Lemming were common, and seen at least once on 56 days out of 90 day field season. Denver Holt, who was studying Snowy Owls in the area, laid out traps to capture small mammals (owlmontana@charlo.net). He indicated this was a low to medium year in 13 years of trapping. Greenland Collared Lemmings were observed on 6 days out of 90 day field season, and Tundra Vole was observed on 1 day out of 90 day field season. Other mammals seen included: Caribou, Arctic Fox, Ringed Seal, Short-tailed Weasel, Beluga, Grey Whale, Bearded Seal, Brown Bear,
Arctic Ground Squirrel.
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Rodent species recorded:
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| Latin | Abundance |
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| Lemmus trimucronatus | common |
| Dicrostonyx torquatus | rare |
| Microtus oeconomus | rare |
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Summary
of fauna studies: |
Investigators: Richard Lanctot, U.S. Fish and Wildlife Service; Audrey Taylor and Nathan Coutsoubos, University of Alaska, Fairbanks; and Bart Kempenaers, Max Planck Research Centre for Ornithology
In 2005, we conducted the third year of a long-term shorebird study at Barrow, Alaska (71.29øN, 156.64øW). The objectives of this study are to (1) collect baseline data on arrival date, nest initiation and effort, clutch and egg size, and hatching success of arctic-breeding shorebirds, (2) to establish a marked population of as many shorebird species as possible that would allow us to obtain estimates of adult survival, mate and site fidelity, and natal philopatry, and (3) to relate weather, predator and prey abundances to shorebird productivity. Data on demographic parameters are vitally needed to understand why many shorebirds are declining.
We located and monitored nests in six 36-ha plots in 2005. Four of the plots were the same as those sampled in 2004. A fifth plot, also sampled in 2004, was modified when the North Slope Borough constructed a road and landfill fence over portions of the plot during the winter of 2004/2005. This plot and the adjoining areas are the subject of intensive study to document possible disturbance from landfill activities on shorebirds (see N. Coutsoubos project). The sixth plot was new, having been moved to a less wet area from that sampled in 2004. We used the same search intensity and methodology as in 2004.
In 2005, we captured and color-marked 179 adults and 379 young. This represents a substantially greater number of marked adults and young relative to 2003 or 2004. Adults captured included 51 DUNL, 44 PESA, 36 SESA, 31 REPH, 8 LBDO, 4 AMGP, 3 RNPH, and 2 BASA. Chicks banded at nests on our plots included 136 PESA, 91 DUNL, 78 REPH, 52 SESA, 10 RNPH, 7 LBDO, 3 BASA and 2 AMGP. Unlike 2004, but similar to 2003, we documented very few cases of renesting in 2005. We captured 26 DUNL, 2 SESA and 1 REPH that were initially marked in prior years. Other marked birds were resighted but the total number has not been quantified yet.
Three other studies were also occurring at this location. Their summaries follow:
(1) Behavioral Ecology of Pectoral Sandpipers
Investigators: Bart Kempenaers and Mihai Valcu, Max Planck Institute for Ornithology, and Richard Lanctot, U.S. Fish and Wildlife Service
In 2004, we began a study in Barrow to investigate the mating system of the Pectoral Sandpiper. The species has been described as polygynous, serially polygynous or promiscuous, but detailed behavioral data on individually marked males and females in combination with parentage analyses are still lacking. The main aims of our study are to describe the mating strategies of males, and the mate sampling behavior and mate choice of females. A secondary aim is to collect baseline data on site fidelity, arrival date, nest initiation, and hatching success of this species.
In 2005, we continued our field study, now focusing on a 2 km2 study area where we captured 67 adult females and 80 adult males. One male was a recapture from 2004. All individuals were measured, blood sampled, and individually marked with color bands. Eleven females and 39 males were also equipped with a radio-transmitter. Using radio-tracking, we located each bird on a daily basis and collected behavioral data by following target birds for one hour at a time. We found 65 nests, of which one was a re-nest after predation. Because nest predation was expected to be high, we replaced eggs with dummy eggs and artificially incubated the eggs in 59 nests. The eggs of 52 broods hatched successfully and were transferred to females that incubated the dummy eggs. Observations showed that incubating females readily accepted the chicks. In total, we collected DNA material from 238 chicks belonging to 66 broods.
(2) Behavioral Ecology of Semipalmated Sandpipers
Investigators: Bart Kempenaers and Mihai Valcu, Max Planck Institute for Ornithology, and Richard Lanctot, U.S. Fish and Wildlife Service
In 2003, we began a study in Barrow to investigate the mating system of the Semipalmated Sandpiper. The main aims of our study are (1) to obtain information about the occurrence of extra-pair paternity to test hypotheses about the evolution of avian promiscuity and (2) to obtain data on breeding site and mate fidelity within and between breeding seasons to test hypotheses about the adaptive value of divorce. A secondary aim is to collect baseline data on survival, arrival date, and breeding success in this species. We are using a combination of field data and molecular analyses using microsatellite markers.
In 2005, we continued our field study in a 2 km2 study area where we captured 58 adult individuals. The recapture rate was 55% (for males) and 23% (for females). All individuals were measured, blood sampled, and individually marked with colour bands. We found a total of 50 nests (2003: 51, 2004: 93) and collected DNA material from 156 chicks, belonging to 48 broods. Nest predation was extremely low this year, possibly due to a predator control program targeting arctic foxes in Barrow area.
(3) Pre-migratory movements and physiology of shorebirds staging on Alaska's North Slope
Investigators: Audrey Taylor and Abby Powell, University of Alaska Fairbanks, and Richard Lanctot, U.S. Fish and Wildlife Service
Little information exists to quantify pre-migratory shorebird distribution across Alaska's North Slope or what factors may influence site selection, movement patterns, or residency times. This information is critical given increased levels of human activity and development near littoral areas across the Arctic Coast. This project was initiated to gain a better understanding of the abundance, distribution, phenology, movements, and physiology of post-breeding shorebirds during the staging period, and to aid in assessing how future industrial and human activity across the North Slope may affect shorebird populations. The specific objectives for this research are (1) to assess the abundance, distribution, and species composition of shorebirds staging along North Slope coastlines prior to the fall migration, (2) to quantify phenological aspects of staging, such as timing of arrival after breeding for adult and hatch-year birds, overall and species-specific peaks in shorebird numbers, residency times at staging sites, and movement patterns of birds across the North Slope, and (3) to examine differences in measures of physiological condition (fattening rates and stress hormone concentrations) among species and sites.
In 2005, we conducted the first aerial survey specifically designed to count staging shorebirds along the entire North Slope coastline. We surveyed 2468 km of shoreline from the southern end of Kasegaluk Lagoon (69.28490øN, 163.27091øW) to the eastern border of the Arctic National Wildlife Refuge (69.66046øN, 141.06690øW) between 7 and 16 August 2005. Approximately 16,850 individual shorebirds were counted during the survey; the majority of these were small calidrid sandpipers and phalaropes. We also expanded our site-specific studies examining staging phenology and physiology from one location (Barrow) to five locations across the North Slope (Barrow, Peard Bay, Colville River delta, Sagavanirktok River delta, and Okpilak River delta). Personnel at each location conducted regular surveys to examine shorebird abundance, distribution, species composition, and habitat use from late July to late August. Field camp crews also captured birds to collect blood samples for physiological analysis, and to band and radio-equip individuals to determine residency time at each site. In total, we banded 410 shorebirds across the North Slope (dunlin, western sandpipers, semipalmated sandpipers, red phalaropes, and red-necked phalaropes), collected blood from 337 individuals, and radio-equipped 49 adults and 70 hatch-year birds of the same five species as listed above. Each camp maintained an automated telemetry station and conducted manual telemetry on a regular basis to examine the probability of birds dispersing between and among breeding and staging areas. Three remote automated telemetry stations located at the Ikpikpuk Delta, at the Canning River Delta, and in Kasegaluk Lagoon monitored birds moving to these sites.
Initial analysis of data collected at each field camp showed that numbers of staging shorebirds fluctuated substantially throughout the late July-late August study period, and that the date of peak staging abundance increased from west to east across the North Slope. Wind and weather had a major effect on the distribution of shorebirds at staging areas, particularly when winds switched from east to west and back. Semipalmated sandpipers were the most common species at all field camps. Dunlin were present everywhere across the Slope and increased in number later in August compared to other species. Red phalaropes were dominant on the western side of the Slope, giving way to red-necked phalaropes at the eastern field camps. Residency time of banded and radio-equipped birds varied within and among field camps and across shorebird species. Dunlin appeared to remain the longest at all field camp locations. Most banded and radio-tagged birds moved widely around each field camp's study area as indicated by manual and automatic telemetry results. Data entry and analysis is ongoing and is expected to comprise the majority of the fall and winter.
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