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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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3.06
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31.07
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12
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WEATHER
CONDITIONS
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Weather conditions: |
| This report represents the conclusion of five years of intensive breeding ecology work on shorebirds at Barrow. Relative to previous years, snow melt occurred relatively early and June and July were relatively warm and dry with little rainfall. On flat areas snow cover reduced to 50% on 8 June and was completely gone on 13 June. No severe storm took place during the field season that lasted from 3 June to 31 July.
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| Date of 50%
snow-cover: |
8.06
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| Date of ice-break on
rivers: |
no river nearby
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| Date of final loss of
snow: |
13.06
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BIOTIC
CONDITIONS
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| Rodents abundance evaluation: |
average
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Breeding conditions:
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Arctic Foxes were common, but their numbers were reduced by removal (killing) from the study area in spring as part of a Steller's Eider Recovery Management Action. One dead Red Fox was seen.
There were few Snowy Owls and Short-eared Owls in the area and they were not breeding. Also Skuas were not breeding, and among three skua species only Arctic Skua was common. Glaucous Gulls were abundant and breeding. Northern Harrier, Rough-legged Bazzard and Golden Eagle were recorded.
We located and monitored nests in six 36-ha plots in 2007. All six plots were the same as those sampled in 2005 and 2006. We used the same search intensity and methodology as from 2004 to 2006. The breeding density of all shorebird species on our study area was 52.1 nests/km2 in 2003, 66.6 in 2004, 63.0 in 2005, 150.5 in 2006, and 88.9 in 2007 (overall average density across years was 84.2).
In 2007, we recorded the highest breeding density of two of the four most abundant shorebird species that nested in the area during the five years of our study. These included Dunlin (19.0 nests/km2) and Semipalmated Sandpiper (11.1). American Golden-Plovers were also more abundant in 2007 than in any previous year with a density of 4.2 nests/km2. Red Phalaropes and Pectoral Sandpiper nest density was 1/2 and 1/3 of the density found in 2006, with 27.3 and 13.4 nests/km2. Interestingly, virtually all of the monogamous species present on our study area had the highest nest densities ever recorded, whereas the polyandrous and polygynous species had below normal numbers (based on our 5-year running average). A total of 192 nests were located on our plots and another 143 nests were found outside the plot boundaries. Nests on plots included 29 Pectoral Sandpiper, 59 Grey Phalarope, 41 Dunlin, 24 Semipalmated Sandpiper, 24 Long-billed Dowitcher, 6 Red-necked Phalarope, and 9 American Golden-Plover. Baird's, Buff-breasted, White-rumped, and Western sandpipers were not observed on our plots in 2007.
The first shorebird clutch was initiated on 3 June and the last on the 2 July in 2007 (on or within 1 day for both dates in previous years). Peak initiation date was the 8 June and median initiation date was the 11 June; this is within 1-2 days of median dates in earlier years. The median nest initiation dates for the more abundant species were the 9 June for Dunlins, 8 June for Semipalmated Sandpipers, 10 June for Red Phalarope, and 14 June for Pectoral Sandpipers. These dates are either the earliest or equal to the earliest dates of nest initiation documented during our 5-year study.
Predators destroyed only 11.1% of the nests in 2007 compared to 8.3% in 2006, 11.2% in 2005, 67.9% in 2004, and 42.6% in 2003. Like 2005-2006, hatching success of shorebird nests was extremely high in 2007, compared to the dismal levels observed in 2003 and 2004. This is most likely because Arctic Foxes were removed from the study area. Among the more abundant species, hatching success (No. hatching at least one young/total number of nests) was highest in Red-necked Phalarope (100%, n=9), followed by Dunlin (92.9%, n=70), Red Phalarope (84.6%, n=65), Semipalmated Sandpipers (84.6%, n=39), Long-billed Dowitchers (56.5%, n=23), and Pectoral Sandpiper (84.4%, n=45).
We also investigated the propensity of the Dunlin to lay replacement clutches by experimentally removing the first clutch of eggs. Of the 20 pairs, 17 females (85%) initiated a replacement clutch. Fifteen females that laid a replacement clutch were found with their original mate and laid their replacement clutch on average 232 m from their initial clutch (range 70-398 m). Conversely, one female laid her second clutch 7.2 km away and did not keep her original mate. The average number of days from first clutch collection to initiation of the replacement clutch was 6.7 days (range 3-15 days). The high rate of replacement clutch laying we found in this study calls into question assumptions commonly used when estimating shorebird productivity and population size.
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Rodent dynamics:
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| Lemming numbers were much lower in 2007 relative to the very high year in 2006, but these rodents were more common than 2003-2005. 30-40 Brown Lemmings were seen per day in June, and in mid-20s/day in July. Tundra Voles were observed on 2 days during the 60 day field season. There was no capture data.
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Rodent species recorded:
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| Latin | Abundance |
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| Lemmus trimucronatus | common |
| Microtus oeconomus | rare |
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Summary
of fauna studies: |
We continue to conduct ancillary studies as time allows at Barrow. Avian influenza sampling was a prominent feature of our work in 2006 and 2007 - all captured birds were swabbed to test for the highly pathogenic H5N1 avian influenza virus. Nathan Coutsoubos (PhD candidate, University of Alaska, Fairbanks) completed the third field season of his PhD studies investigating how the construction of a landfill and the experimental flooding/draining of a wetland influence shorebirds (see below). We also placed radio transmitters on 20 females Dunlin to help River Gates (prospective MS candidate, UAF) document rates of clutch replacement laying (see below). Audrey Taylor (PhD candidate, University of Alaska Fairbanks) documented movements to postbreeding sites (see below). Finally, we collected eggs from Dunlin as part of a collaborative project with Sarah Jamieson (PhD candidate, Simon Fraser University) to investigate whether shorebirds use endogenous or exogenous resources to produce eggs.
We continued with a second summer of surveys on four 1000m tundra transects first surveyed in the late 1970s as part of a baseline monitoring project. Surveys were conducted weekly from 11 June to 6 July. In total, 467 avian detections were recorded involving 20 species, including 224 shorebird detections of seven species. The most commonly encountered shorebirds (unadjusted counts) include Red Phalarope (62 detections, 99 individuals), Pectoral Sandpiper (53 and 64), Dunlin (44 and 50), and Long-billed Dowitcher (30 and 46). A comparison of data collected in the 1970s and now will demonstrate whether the distribution and abundance of local shorebird populations have changed over time. Data analysis is able to proceed using both the analytical techniques of the late 1970s and modern distance sampling methods, providing a robust comparison of then and now.
In 2007 we continued our field study on the pectoral sandpipers in the same area of 2.6 km2 as in 2006 (71.32 N, 156.66 W). We captured (using mistnets or nest-traps) 176 adult individuals (123 males and 53 females) and all individuals were marked with a unique combination of color bands. We measured the tarsus, wing and culmen length of each captured bird and collected a small blood sample for hormone and genetic analysis. The color bands allowed us to re-sight each individual present on the study area on a daily basis. For each re-sighting, the individual's GPS position and a set of standardized behavioral measures were recorded. Only 37 males were observed in our study area for longer than 5 days (i.e. were residents). The relatively low number of pectoral sandpiper males (30% resident males, about 47% from the total number of resident males in 2006) and the reduced number of nests in our study area (31 nests, only 37% from the total number of nests in 2006) suggest that 2007 was a low density year for the pectoral sandpipers in Barrow. The overall hatching success (at least one hatched young per nest) was 65%, which is 20% less in comparison with 2006. This was due to a relatively high rate of predation (9 cases) and desertion (11 cases).
A total of 42 small radio-transmitters where attached to 17 males and 25 females. This allowed us to continuously monitor a subset of birds using an automated activity recorder. Preliminary results suggest that the activity of pectoral sandpiper males is very high throughout the day and night and males seldom sleep before all females have started incubation.
Recent Publications and Dissertations
Peer Reviewed Publications
Liebezeit, J. R., P. A. Smith, R. B. Lanctot, C. Gratto-Trevor, H. Schekkerman, D. Tracy, J. A. R. Robinson, H. Meltofte, S. Kendall, R. J. Rodrigues, J. A. Morse, and B. J. McCaffery. 2007. Determining incubation stage of shorebird eggs using the flotation method: species-specific and generalized regression models. Condor 109:32-47.
Johnson, J. A., R. B. Lanctot, B. A. Andres, J. R. Bart, S. C. Brown, S. J. Kendall, and D. C. Payer. 2007. Distribution of breeding shorebirds on the Arctic Coastal Plain of Alaska. Arctic 60:277-293.
Naves, L. C., R. B. Lanctot. A. R. Taylor, and N. P. Coutsoubos. 2008. Do Arctic shorebirds lay replacement clutches? Assessment, ecological correlates, and ramifications to monitoring. Wader Study Group Bulletin (in press).
Ip, H. P., P. L. Flint, J. C. Franson, R. J. Dusek, D. V. Derksen, R. E. Gill, Jr., C. R. Ely, J. M. Pearce, R. B. Lanctot, S. M. Matsuoka, D. B. Irons, J. B. Fischer, R. M. Oates, M. R. Petersen, T. F. Fondell, D. A. Rocque, J. C. Pedersen, T. C. Rothe, and K. Wohl. 2008. Prevalence of Influenza A Viruses in Wild Migratory Birds in Alaska: Patterns of Variation in Detection at the Crossroads of International Flyways. Journal of Virology (in press).
Non-peer reviewed Publications
Gates, H. R., R. B. Lanctot, and A. R. Taylor. 2007. Experiment evidence of clutch replacement in Dunlin (Calidris alpina arcticola), Preliminary Results, 2007. Unpubl. report for Canadian Wildlife Service by U.S. Fish and Wildlife Service, Anchorage, Alaska.
Fernandez, G., J. B. Buchanan, R. E. Gill, Jr., R. B. Lanctot, and N. Warnock. 2008. Conservation Plan for the Dunlin, version 1.0. Manomet Center for Conservation Science, Manomet, Massachusetts.
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