SURVEYS OF LEDGE-NESTING SEABIRDS AT …...AMNWR 2019/06 SURVEYS OF LEDGE-NESTING SEABIRDS AT SELECTED SITES IN THE NORTHERN BERING SEA AND EASTERN CHUKCHI SEA, JULY-AUGUST 2018 Donald

AMNWR 2019/06 SURVEYS OF LEDGE-NESTING SEABIRDS AT SELECTED SITES IN THE NORTHERN BERING SEA

AND EASTERN CHUKCHI SEA, JULY-AUGUST 2018

Donald E. Dragoo, Marianne Aplin, Aaron Christ, Heather M. Renner, Nora A. Rojek, Jeffrey C. Williams, and Kara Zwickey

Key Words: Alaska, Bering Sea, black-legged kittiwake, Bluff, Cape Lewis, Cape Lisburne, Cape Thompson, Chamisso Island, Chukchi Sea, common murre, Kotzebue Sound, Norton Sound, pelagic cormorant, Phalacrocorax pelagicus, populations, productivity, Rissa tridactyla, seabirds, Sledge Island, thick-billed murre, Topkok Head, Uria aalge, Uria lomvia, wildlife

U.S. Fish and Wildlife Service Alaska Maritime National Wildlife Refuge

95 Sterling Hwy, Suite 1 Homer, Alaska, USA 99603-7472

September 2019

Cite as: Dragoo, D. E., M. Aplin, A. Christ, H. M. Renner, N. A. Rojek, J. C. Williams, and K. Zwickey.

2019. Surveys of ledge-nesting seabirds at selected sites in the northern Bering Sea and eastern Chukchi Sea, July-August 2018. U.S. Fish and Wildl. Serv. Rep., AMNWR 2019/06. Homer, Alaska.

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TABLE OF CONTENTS Page

INTRODUCTION ........................................................................................................................................... 1 STUDY AREA ............................................................................................................................................... 1 METHODS ................................................................................................................................................... 2 Cruise itinerary ........................................................................................................................................ 3 INTERESTING OBSERVATIONS ................................................................................................................ 4 ACKNOWLEDGEMENTS ............................................................................................................................. 6 REFERENCES .............................................................................................................................................. 6 MAPS ........................................................................................................................................................... 8 FIGURES AND TABLES ............................................................................................................................. 10 Land-based index plots ........................................................................................................................ 11 Common and thick-billed murres ................................................................................................... 11 Black-legged kittiwakes .................................................................................................................. 20 Black-legged kittiwake nests .......................................................................................................... 29 Boat-based index plots ......................................................................................................................... 32 Common and thick-billed murres ................................................................................................... 32 Black-legged kittiwakes .................................................................................................................. 36 Black-legged kittiwake nests .......................................................................................................... 40 Locations of index plots ........................................................................................................................ 44 Cape Thompson ............................................................................................................................. 44 Cape Lisburne ................................................................................................................................ 45

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INTRODUCTION The eastern Chukchi Sea supports two large seabird nesting colonies, at capes Lisburne and Thompson. Both of these colonies are part of the Chukchi Sea Unit of the Alaska Maritime National Wildlife Refuge (AMNWR). Research of the seabird communities in this area was first conducted in 1959-1961 as part of the environmental assessment of the Cape Thompson area for Project Chariot, a U.S. Atomic Energy Commission proposal to use nuclear devices to create a harbor in the lower Ogoturuk Creek valley (Swartz 1966). Seabird data have been collected regularly at Cape Lisburne and sporadically at other Chukchi colonies since, sometimes with long intervals between visits. In 2018, the AMNWR vessel R/V Tiglax voyaged through the northern Bering Sea and, for the first time in 30 years, into the eastern Chukchi Sea (Figure 1). The purpose of the cruise was to conduct biological monitoring at Cape Thompson and, if possible, other Refuge sites in the area (Figure 2). We also wanted to assess the condition of Cape Thompson seabird monitoring plots, some of which were originally established in 1959, to determine if present-day counts would be comparable to those from the past. No refuge crew had been to Cape Thompson since 1995. STUDY AREA Cape Thompson: The Cape Thompson seabird colonies are situated in the Cape Thompson Subunit, Chukchi Sea Unit of the AMNWR at about 68⁰08’ N, 166º21’ W, approximately 40 km southeast of Point Hope, Alaska. The seabird nesting area comprises five large cliff faces (Colonies 1-5). Swartz (1966) estimated that the Cape Thompson colonies contained about 420,000 birds total (~393,000 common and thick-billed murres, and ~30,000 black-legged kittiwakes). Cape Lisburne: The Cape Lisburne seabird colony is located in the Ann Stevens-Cape Lisburne Subunit, Chukchi Sea Unit of the AMNWR at about 68º52’ N, 166º05’ W, approximately 62 km northeast of Point Hope, Alaska. Nesting habitat consists of about 7 km of precipitous, nearly continuous 15-200 m-high sedimentary limestone and shale sea-cliffs that begin about 1 km south of Kay Creek and end approximately 1 km west of the Cape Lisburne U. S. Air Force Long Range Radar Site (LRRS) runway (Roseneau et al. 2000). Currently, the seabird colony is estimated to number about 400,000-500,000 murres (comprising about 25-30% common murres and 70-75% thick-billed murres), 20,000-30,000 black-legged kittiwakes, and a total of a few thousand pelagic cormorants (Phalacrocorax pelagicus), glaucous gulls (Larus hyperboreus), black guillemots (Cepphus grylle), parakeet auklets (Aethia psittacula), and horned and tufted puffins (Fratercula corniculata and F. cirrhata, respectively; Roseneau 2010 and Dragoo et al. 2017). Cape Lewis: Cape Lewis is in the Chukchi Sea Unit of the AMNWR, approximately 46 km northeast of Point Hope, Alaska, at about 68°43’ N, 166°11’ W.

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Chamisso Island area: Chamisso and Puffin islands and the adjacent sea stacks are located in the Chukchi Sea Unit of the AMNWR, approximately 85 km southeast of Kotzebue, Alaska, at about 66°13’ N, 161°50’ W. The Chamisso Islands group is one of the oldest refuges in the system and was one of the first designated wilderness areas in the U. S. It was established as the Chamisso Island National Wildlife Refuge (NWR) by President William Howard Taft in 1912, designated as wilderness in 1975, and incorporated into AMNWR at its creation in 1980. The Chamisso Island group is estimated to contain more than 60% of the breeding seabirds in Kotzebue Sound (Nelson and Sowls 1985). Norton Sound: Norton Sound is located in the Bering Sea Unit of the AMNWR, at about 64° N, 164° W, near Nome, Alaska. There is a large seabird colony at Bluff that was studied periodically between 1975 and 2012. METHODS Personnel: The U. S. Fish and Wildlife Service crew consisted of Marianne Aplin, Aaron Christ, Don Dragoo, Heather Renner, Nora Rojek, Jeff Williams, and Kara Zwickey. R/V Tiglax crew: John Faris, Dan Puterbaugh, Eric Nelson, Andy Velsko, Marin Lee, and Morgan Stewart. Data Collection and Analysis: The methods used to collect and analyze seabird-related data followed the procedures described in Fadely et al. (1989), Roseneau et al. (2000), and Alaska Maritime National Wildlife Refuge (2018) with the following exceptions:

• Murre productivity was assessed by recording the number of birds that were either standing (obviously with no egg or chick), or in an incubating or brooding posture (indicating the possibility of the presence of an egg or chick). The total number of birds in incubating and brooding posture was then divided by the total number of birds whose posture was recorded to produce an estimate of the maximum productivity. It should be noted, however, that this is the maximum potential productivity and it’s likely that the actual value was lower since some of the murres exhibiting incubating or brooding postures may not have had young.

• Kittiwake productivity was estimated by recording the number of nests that obviously were empty, the number of eggs or chicks present in nests, and the number of nests on which an adult kittiwake was sitting. Sitting birds prevented a determination of whether their nests contained eggs or chicks. The total number of birds with eggs or chicks plus the number of birds sitting was divided by the total number of nests whose status was recorded to produce an estimate of the maximum productivity. It should be noted, however, that this is the maximum potential productivity and it’s likely that the actual value was lower since some of the nests with sitting birds may not have contained young.

• The land-based plots that we refer to as “Swartz index plots” were originally set up beginning in 1959 (e.g., Table 4). The boat-based plots at Colony 4 also date from the Swartz era (e.g., Table 19). The other set of land-based index plots (e.g., Table 1) were established in 1988 (Fadely et al. 1989).

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• The entirety of Cape Thompson Colonies 1, 2, 3, 4, and 5 were photographed from a skiff. All of the cliffs comprising the Cape Lisburne boat-based population plots also were photographed in 2018. Cape Thompson land-based plots at Colonies 3, 4, and 5 were photographed and counted, as were the boat-based plots at Colony 4. Photographs of the plots, including those that were not counted in 2018, are archived at AMNWR offices.

Counts made from photographs: Counts of adult birds and nests on photographs for Capes Thompson and Lisburne plots were completed by using the computer program GIMP™ 2.10.10. We created a new GIMP file for each plot. Photos were chosen based on clarity and whether they contained the entire plot. The image file for a plot was imported to a base layer in GIMP. Plot boundaries from historical photographs were drawn on a second layer. Next, different dot colors and layers were assigned to three categories, murres, black-legged kittiwakes, and black-legged kittiwake nests. A dot composed of 25 pixels was placed over each bird or nest within the boundary area of each plot. After the plot was completed, the total number of pixels (counted by software) for each category was divided by 25 to obtain the number of dots, each dot representing a bird or nest. R/V Tiglax Cruise itinerary: 30 July: Departed Nome just before midnight heading for Cape Thompson. 31 July: Enroute to Cape Thompson, via King and Little Diomede islands, and Fairway Rock. Crossed the Arctic Circle. 1 August: Arrived in the Cape Thompson area. Began photographing the five colonies from skiffs. We also completed a boat-based population count of plots at Colony 4. 2 August: Finished photographing seabird colonies from the skiffs. Visited Project Chariot site to assess condition of the landing strip. Completed a boat-based count of Colony 4 plots. 3 August: Located observation points and counted birds on land-based plots in Colony 4 and Colony 5. We also conducted counts of land-based plots at Colony 3. 4 August: Conducted a count of land-based plots at Colonies 4 and 5. Also documented productivity of murres and kittiwakes. Cruised to Cape Lisburne overnight. 5 August: Photographed all of the plots at Cape Lisburne from skiffs. Attempted to count birds on boat-based plots but the seas were too choppy to complete the count. Photographed and did a rough count of birds at Cape Lewis. Began cruising to Kotzebue Sound and the Chamisso Island group overnight. 6 August: Enroute to Kotzebue Sound. 7 August: Went ashore at Chamisso Island and attempted to circumnavigate the island in the skiffs, to no avail due to rough seas. Began the return cruise to Nome. 8 August: Enroute to Nome. Arrived at Sledge Island in the evening and skiffed to and around the island. 9 August: Skiff surveys of Bluff and Topkok Head in Norton Sound. Returned to Nome in the evening.

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INTERESTING OBSERVATIONS Cape Thompson:

• A quick check of murre productivity in the Cape Thompson area revealed that very few murres appeared to have eggs or chicks in 2018. Out of more than a thousand murres checked for productivity, only about 2.4% were in incubating or brooding postures. All of the birds that were observed to be in brooding posture (indicating that they had a chick) during two observation days were common murres, suggesting that common murres had higher productivity than thick-billed murres in the Cape Thompson area in 2018.

• Murre numbers were down in 2018 on both the common and Swartz land-based plots. Kittiwake numbers were similar to the past on both common and Swartz land-based plots.

• Murre numbers were lower in 2018 on boat-based population plots than in previous count years. Black-legged kittiwake adult and nest numbers were within the range of values from previous count years.

• Murre species composition was evaluated on seven Colony 5 plots on 5 August. We found that approximately 96% of the murres occupying the plots on that day were thick-billed murres. The average ratio of thick-billed murres to common murres reported in past years was about 44% thick-billed murres to 56% common murres.

• During a quick check of black-legged kittiwake productivity in the Cape Thompson area, an estimate of the maximum reproductive potential was calculated to be about 0.54 chicks fledged/nest. This is similar to the average productivity reported for Cape Thompson kittiwakes from past monitoring efforts (Dragoo et al. 2001). We were a bit early in the breeding season to be able to see large chicks in the nests.

• The beach from which the Colony 3 land-based population plots are counted was eroded to the point where observers would have had to stand out in the water to view the plots from the distance and angle at which the plot photographs had been taken in the past. We established a new Colony 3 plot (3-2D) that can be viewed from the current beach.

• Some of the observation points for the land-based population plots at Colonies 4 and 5 have eroded compared to the plot photographs that were taken in 1988. In one case (observation point 5-1) observers noted that the observation point had “moved <10 feet inland due to erosion” (Table 3). Observers believed that, although some of the areas within the plot boundaries of the old photographs were not visible from the new observation point, the 2018 counts were comparable with those from the past, especially for the Swartz plots.

• We visited the Project Chariot site to assess the condition of the airstrip and found that it appears to be in adequate condition to allow for use by the type of small aircraft that was used in past Cape Thompson camp deployments.

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Cape Lisburne:

• During a quick check of black-legged kittiwake productivity in the Cape Lisburne area, an estimate of the maximum reproductive potential was calculated to be about 0.67 chicks fledged/nest. This is slightly higher than the average productivity reported for Cape Lisburne kittiwakes from past monitoring efforts (Dragoo et al. 2018). We were a bit early in the breeding season to be able to see large chicks in the nests.

• The 2018 marine mammal monitoring crew at Cape Lisburne (Sasha Ertl and Brian O’Donnell, dnaEnvironmental Inc.) made the following observations: “NO young murre, puffin or cormorant observed. NO alcids ever observed carrying fish. Relatively few hatch-year Kittiwakes seen; however, Sasha Ertl observed many young Kittiwakes on ledges and in the water on September 30th.”

• Sasha Ertl also stated in an e-mail (dated 25 September 2018): “Brian and I have been discussing the fact that neither of us saw any alcid chicks this year. I know that’s both not good news and not unique-to-Lisburne news. We are both hoping we just missed it, but I took a bunch of pics of the cliffs to look for young and didn’t see any. We also were waiting for the dad/chick murres, and never saw that either. Did see young kittiwakes and glaucous gulls though. And lots of adult alcids in the cliffs. And like I reported before, there are huge groups of gulls out on the water, even still! They must be on bait balls? So I don’t understand the lack of alcid chicks.”

Cape Lewis:

• We estimated that there was a minimum of 20,790 murres at Cape Lewis (counted by 10s and 100s), similar to the 25,000 reported in 1977 (Sowls et al. 1978).

• Observers noted that there appeared to be little or no murre or kittiwake productivity at Cape Lewis in 2018.

• The pinnacles at Cape Lewis are reminiscent of those in the Bryce Canyon area of Utah. Chamisso Island area:

• Rough seas prevented formal surveys but we did note that there were no murres occupying a small colony on Chamisso Island, an area that typically contains upwards of one hundred murres (Dragoo and Slater 2015).

• We made a brief inspection of Puffin Island, but high seas and strong winds prevented any counts. Many hundreds (possibly thousands) of murres were at least attending the cliffs there.

Norton Sound:

• During a quick check of black-legged kittiwake productivity at Sledge Island, an estimate of the maximum reproductive potential was calculated to be about 0.29 chicks fledged/nest. Pelagic cormorants appeared to be doing fairly well at Sledge Island, whereas murres apparently failed to produce young there.

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• A circumnavigation survey of birds at Sledge Island found 976 murres (species combined), 1,934

black-legged kittiwakes, and 277 pelagic cormorants. Our murre counts were similar to those from 1984 (Byrd 1984), but much lower than 1976 counts (Sowls et al. 1978). The 2018 counts of black-legged kittiwakes was similar to the 1976 count, but almost twice the number counted in 1984. Pelagic cormorant numbers appear to be increasing at Sledge Island but the number of nests was down in 2018 compared to 1984 (11 nests in 2018 vs 100 nests in 1984).

• During a quick check of black-legged kittiwake productivity in the Bluff area, an estimate of the

maximum reproductive potential was calculated to be about 0.29 chicks fledged/nest. This is below the average productivity reported for Bluff kittiwakes from past monitoring efforts (Dragoo et al. 2011).

• A quick check of murre productivity at Bluff revealed that only about 13% of birds appeared to be in incubating or brooding posture. Just one chick was observed.

• Large numbers of murres flushed every time we approached the cliffs at Bluff in the skiff.

• Topkok Head contained mostly pelagic cormorants and glaucous gulls, with dozens of pigeon guillemots, and a few horned and tufted puffins. Many of the pelagic cormorant nests contained large chicks (often more than three chicks/nest). Numerous cormorant chicks were near, or past, fledging age.

• A golden eagle nest was observed at Topkok head.

ACKNOWLEDGEMENTS We would like to thank the crew of the R/V Tiglax for getting us there and back safely and well fed. Frances Murphy was always ready to provide a “Ride ‘em cowboy” for us during our many lumpy skiff rides. National Park Service in Nome provided bunkhouse space. We thank the estate of Wilfred W. Lane, Sr. for access to their allotment at the Chariot site. We also thank Melissa Petschauer for spending the hours necessary to count birds and nests on the 2018 Cape Thompson population plot photographs, and Arthur Kettle for helping get Melissa set up and able to do the photo counts. Finally, we would like to express our gratitude to the staff of the Alaska Maritime National Wildlife Refuge for their continued help and support. Cover photo of “Puddles” the blue goose was taken by Aaron Christ. REFERENCES Alaska Maritime National Wildlife Refuge. 2018. Standardized protocols for annual seabird monitoring

camps at Aiktak, Buldir, Chowiet, St. George, St. Lazaria and St. Paul islands, Cape Lisburne, and select intermittent sites in the Alaska Maritime National Wildlife Refuge in 2018. U.S. Fish and Wildl. Serv. Report AMNWR 2018/04. Homer, Alaska.

Byrd, G. V. 1984. Observations of flora and fauna in the Bering Sea Unit Alaska Maritime NWR in July 1984. U.S. Fish and Wildl. Serv. Report AMNWR 1984/02. Homer, Alaska.

Dragoo, D. E., G. V. Byrd, and D. B. Irons. 2001. Breeding status, population trends and diets of seabirds in Alaska, 2000. U.S. Fish and Wildl. Serv. Report AMNWR 2001/07. Homer, Alaska.

Dragoo, D. E., G. V. Byrd, and D. B. Irons. 2011. Breeding status, population trends and diets of seabirds in Alaska, 2008. U.S. Fish and Wildl. Serv. Report AMNWR 2011/07. Homer, Alaska.

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Dragoo, D. E., and L. Slater. 2015. Biological monitoring at the Chamisso Island group, Alaska in 2014. U.S. Fish and Wildl. Serv. Report AMNWR 2015/04. Homer, Alaska.

Dragoo, D. E., G. Thomson, and M. D. Romano. 2017. Biological monitoring at Cape Lisburne, Alaska in 2017. U. S. Fish and Wildl. Serv. Report AMNWR 2017/15. Homer, Alaska.

Dragoo, D. E., H. M. Renner, and R. S. A. Kaler. 2018. Breeding status and population trends of seabirds in Alaska, 2017. U.S. Fish and Wildl. Serv. Report AMNWR 2018/02. Homer, Alaska.

Ertl, S., and B. O’Donnell, dnaEnvironmental Inc. Personal Communication, 2018. Anchorage, Alaska. Fadely, B. S., J. F. Piatt, S. A. Hatch, and D. G. Roseneau. 1989. Populations, productivity, and feeding

habits of seabirds at Cape Thompson, Alaska. Minerals Mgmt. Serv., OCS Study MMS 89-0014. Nelson, J. W., and A. L. Sowls. 1985. Breeding seabird survey of Chamisso Island and southern Kotzebue

Sound, 8-20 August 1981. U. S. Fish and Wildl. Serv. Report. Anchorage, Alaska (AMNWR 1985/17).

Nishimoto, M., and V. M. Mendenhall. 1994. Cape Thompson. Chap. 6, pp. 94-109 in Mendenhall, V. M. (ed.). Monitoring of populations and productivity of seabirds at St. Matthew Island, Bluff, Little Diomede Island, and Cape Thompson, Alaska, 1991. Minerals Mgmt. Serv., OCS Study MMS 93-0067.

Roseneau, D. G., M. F. Chance, P. F. Chance, and G. V. Byrd. 2000. Monitoring seabird populations in areas of oil and gas development on the Alaskan continental shelf: Cape Lisburne and Cape Thompson seabird studies, 1995-1997. Final report by the Alaska Maritime National Wildlife Refuge, Homer, Alaska to the U.S. Geological Survey Biological Resources Division, Western Regional Office, Seattle WA (USGS Study USGS/BRD/CR-1999-0002 and OCS Study 99-0011). U. S. Fish and Wildl. Serv. Report AMNWR 2000/09. Homer, Alaska.

Roseneau, D. G. 2010. Monitoring murres and kittiwakes at Cape Lisburne, Alaska, 1976-2009. AMNWR monitoring poster prepared 23 February 2010, AMNWR, Homer, Alaska.

Sharp. B. E., 1993. Populations and productivity of seabirds at Cape Thompson in 1990. Pp. 94-139 in Mendenhall, V. M. (ed.). Monitoring populations and productivity of seabirds at Cape Peirce, Bluff, and Cape Thompson, Alaska, 1990. Minerals Mgmt. Serv., OCS Study MMS 92-0047.

Sowls, A. L., S. A. Hatch, and C. J. Lensink. 1978. Catalog of Alaskan seabird colonies. FWSLOBS-78/78. USFWS Biol. Serv. Prog. Anchorage, Alaska.

Springer, A. M., and D. G. Roseneau. 1978. Ecological studies of colonial seabirds at Cape Thompson and Cape Lisburne, Alaska. U. S. Dept. Commer., NOAA OCSEAP, Annual Rept., Vol. 2, pp. 839-960.

Springer, A. M., D. G. Roseneau, E. C. Murphy, and M. I. Springer. 1979. Ecological studies of colonial seabirds at Cape Thompson and Cape Lisburne, Alaska. U.S. Dept. Commer., NOAA OCSEAP, Annual Rept., Vol. 2, pp 517-574.

Swartz, G. 1966. Sea-cliff birds. Pp. 611-678 in N. J. Wilimovsky and J. N. Wolfe (eds.). Environment of the Cape Thompson region, Alaska. U.S. Atomic Energy Commission, Oak Ridge, TN.

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Figure 1. Map of 2018 northern Bering and eastern Chukchi seas cruise (green line is northbound route, red line is southbound).

Point Hope

Kotzebue

Diomedes

Nome

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Figure 2. Map of 2018 Study locations.

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FIGURES AND TABLES

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Figure 3. Mean numbers of murres (species combined) counted on land-based index plots (4-1A, 4-1B, 4-2C, 4-3D, and 4-4E) on Colony 4 at Cape Thompson, Alaska. No counts were conducted in 1989, 1992-1994, or 1996-2017.

0

200

400

600

800

1000

1200

1400

1600

1800

88 90 92 94 96 98 00 02 04 06 08 10 12 14 16 18

Mea

n nu

mbe

r of m

urre

s

Year

12

Table 1. Numbers of murres (species combined) counted on land-based index plots (4-1A, 4-1B, 4-2C, 4-3D, and 4-4E) on Colony 4 at Cape Thompson, Alaska. No counts were conducted in 1989, 1992-1994, or 1996-2017.

Replicate 1988 1990 1991 1995 2018

1 841 1162 1208 1446 950 2 1157 1232 1324 1627 1406 3 1292 980 1405 1605 - 4 1508 1086 1501 1324 - 5 1469 1100 1260 1529 - 6 1368 1090 1263 1469 - 7 1394 1009 1588 1600 - 8 1563 - 1526 - - 9 1376 - - - -

10 1687 - - - -

Mean 1366 1094 1384 1514 1178 n 10 7 8 7 2

SD 235 86 142 109 322 First count 11 Jul 9 Jul 15 Jul 22 Jul 3 Aug Last count 15 Aug 1 Aug 8 Aug 15 Aug 4 Aug

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Figure 4. Mean numbers of murres (species combined) counted on land-based index plots (5-1A, 5-1B, 5-1C, 5-1D, 5-2E, 5-2F, 5-2G, and 5-3H) on Colony 5 at Cape Thompson, Alaska. No counts were conducted in 1989, 1992-1994, or 1996-2017.

0

500

1000

1500

2000

2500

3000

88 90 92 94 96 98 00 02 04 06 08 10 12 14 16 18

Mea

n nu

mbe

r of m

urre

s

Year

14

Table 2. Numbers of murres (species combined) counted on land-based index plots (5-1A, 5-1B, 5-1C, 5-1D, 5-2E, 5-2F, 5-2G, and 5-3H) on Colony 5 at Cape Thompson, Alaska. No counts were conducted in 1989, 1992-1994, or 1996-2017.

Replicate 1988 1990 1991 1995 2018

1 2061 2152 1906 2024 671 2 2407 2418 2575 2715 2003 3 2005 2665 2566 2348 - 4 2095 2590 2240 2354 - 5 2324 2557 2528 2267 - 6 2148 - 2831 2213 - 7 2694 - - 2224 -

Mean 2248 2476 2441 2306 1337 n 7 5 6 7 2


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Table 3. Numbers of murres (species combined) counted on land-based index plots at Cape Thompson, Alaska in 2018.

Date 3-Aug 4-Aug Plot 2018 2018 Notes (Notes in italics are quoted from field notebooks and/or summary data sheets.)

3-1A 3 NCa Plot couldn't be counted from the location at which the previous photos were taken (1988) due to beach erosion. 3-2B 115 NC Plot couldn't be counted from the location at which the previous photos were taken (1988) due to beach erosion. 3-2C 35 NC Plot couldn't be counted from the location at which the previous photos were taken (1988) due to beach erosion. 3-2D 120 NC New plot established in 2018. 4-1A 192 244 4-1B 134 193 4-2C 199 292 4-3D 150 322 “Rebar marker at lower end of tall grass patch” 4-4E 275 355 5-1A 13 22 “Obs. point moved <10 feet inland due to coastal erosion.” "Potential for missing birds on far left edge." 5-1B 137 269 “Obs. point moved <10 feet inland due to coastal erosion.” "Has lost some cliff but can see fine." 5-1C 27 96 “Obs. point moved <10 feet inland due to coastal erosion.” "Lower and right portion not visible." 5-1D 64 455 “Obs. point moved <10 feet inland due to coastal erosion.” "Right-hand portion of Fadely's plot not visible." 5-2E 125 419 5-2F 136 341 5-2F' 55 107 5-2G 112 181 5-3H 2 79 5-3H' 0 34 5-4I 145 304 5-5J 452 807 "Swartz L." 5-6K 119 385 "Swartz M." (Swartz Plot M includes Fadely Plot 5-6K plus Plot 5-K’). 5-6K' 89 138 "Swartz M." (Swartz Plot M includes Fadely Plot 5-6K plus Plot 5-K’). 5-7L 68 NC 5-7L' 35 NC 5-8-M NC 920 5-8N 81 500 5-8N' 0 140

a NC = Plot not counted.

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Figure 5. Numbers of murres (species combined) counted on land-based Swartz index plots 5G, 5L, 5M, 5N, 5O, 5P, and 5Q at Cape Thompson, Alaska. No counts were conducted in 1961-1978, 1980, 1981, 1983-1989, 1992-1994, or 1996-2017. Error bars represent one standard deviation.

0

3,000

6,000

9,000

12,000

15,000

18,000

21,000

60 64 68 72 76 80 84 88 92 96 00 04 08 12 16

Mea

n nu

mbe

r of m

urre

s

Year

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Table 4. Numbers of murres (species combined) counted on land-based Swartz index plots 5G, 5L, 5M, 5N, 5O, 5P, and 5Q at Cape Thompson, Alaska. No counts were conducted in 1961-1978, 1980, 1981, 1983-1989, 1992-1994, or 1996-2017.

Replicate 1960a 1979a 1982a 1990a 1991a 1995a 2018

1 19,879 7,102 8,557 8,524 7,302 6,777 2,482 2 - - - 7,252 - 9,477 5,240 3 - - - - - 7,605 - 4 - - - - - 7,288 - 5 - - - - - 8,885 - 6 - - - - - 8,920 - 7 - - - - - 8,620 -

Mean 19,879 7,102 8,557 7,888 7,302 8,225 3,861 n 1 1 1 2 1 7 2

SD - - - 899 - 1,000 1,950 First count 1 Aug 7 Aug 3 Aug 21 Jul 31 Jul 15 Jul 3 Aug Last count - - - 28 Jul - 14 Aug 4 Aug

a Data are from Roseneau et al. 2000; Table 30.

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Table 5. Numbers of murres (species combined) counted on land-based Swartz index plots at Cape Thompson, Alaska in 2018.

Date 3-Aug 4Aug

Plot 2018 2018 Notes

Swartz 5G 529 1,369 Swartz 5L 452 807 Fadely plot 5-5J Swartz 5M 208 523 Fadely plot 5-6K plus 5-6K' Swartz 5N 213 699 Swartz 5O 294 654 Swartz 5P 705 548 Swartz 5Q 81 640 Fadely 5-8N plus 5-8N'

Table 6. Numbers of murres (species combined) counted from photographs of land-based plots at Cape Thompson, Alaska. Photographs were taken on 3 August 2018.

Plot Birds Notes

4-1A 258 4-1B 142 4-2C 154 4-3D 304 4-4E 446 5-1A 26 5-1B 81 5-1C 21 5-1D 70 5-2E 167 Photo quite far, zooming in a lot creates blurry image. 5-2F 194 Photo quite far, zooming in a lot creates blurry image. 5-2G 144 Photo quite far, zooming in a lot creates blurry image. 5-3H 3 5-4I 98 5-5J 441

Swartz 5-M 477 5-6K 333 Slightly blurry 5-7L 108 5-8M 718 Blurry

Swartz 5-Q 95 Swartz 5-G 462 Photo did not include all of the plot, blurry Swartz 5-N 335 Swartz 5-O 328 Swartz 5-P 571

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Table 7. Numbers of murres (species combined) counted manually and from photographs of land-based plots at Cape Thompson, Alaska in 2018. Photographs were taken and counts were conducted on the same day (3 August 2018). Manual counts were made within 10 minutes of the time when the photographs were taken.

Plot Manual Count Mean on 3 Aug. (Birds) Photo Count (Birds)

4-1A 192 258 4-1B 134 142 4-2C 199 154 4-3D 150 304 4-4E 275 446 5-1A 13 26 5-1B 137 81 5-1C 27 21 5-1D 64 70 5-2E 125 167 5-2F 191 194 5-2G 112 144 5-3H 2 3 5-4I 145 98

5-5J (Swartz L) 452 441 Swartz 5-M 208 477

5-6K 208 333 5-7L 103 108 5-8M NCa 718

Swartz 5-Q 81 95 Swartz 5-G 529 462 Swartz 5-N 213 335 Swartz 5-O 294 328 Swartz 5-P 705 571


20

Figure 6. Mean numbers of black-legged kittiwakes counted on land-based index plots (4-1A, 4-1B, 4-2C, 4-3D, and 4-4E) on Colony 4 at Cape Thompson, Alaska. No counts were conducted in 1989, 1992-1994, or 1996-2017.

0

100

200

300

400

500

600

700

800

88 90 92 94 96 98 00 02 04 06 08 10 12 14 16 18

Mea

n nu

mbe

r of k

ittiw

akes

Year

21

Table 8. Numbers of black-legged kittiwakes counted on land-based index plots (4-1A, 4-1B, 4-2C, 4-3D, and 4-4E) on Colony 4 at Cape Thompson, Alaska. No counts were conducted in 1989, 1992-1994, or 1996-2017.

Replicate 1988 1990 1991 1995 2018

1 547 663 500 255 754 2 568 646 536 551 738 3 567 586 545 397 - 4 508 546 516 426 - 5 466 642 531 355 - 6 426 610 614 337 - 7 464 624 712 547 - 8 514 682 692 - -

Mean 508 625 581 410 746 n 8 8 8 7 2


22

Figure 7. Mean numbers of black-legged kittiwakes counted on land-based index plots (5-1A, 5-1B, 5-1C, 5-2F, and 5-2G) on Colony 5 at Cape Thompson, Alaska. No counts were conducted in 1989, 1992-1994, or 1996-2017.

0

50

100

150

200

250

300

350

400

88 90 92 94 96 98 00 02 04 06 08 10 12 14 16 18

Mea

n nu

mbe

r of k

ittiw

akes

Year

23

Table 9. Numbers of black-legged kittiwakes counted on land-based index plots (5-1A, 5-1B, 5-1C, 5-2F, and 5-2G) on Colony 5 at Cape Thompson, Alaska. No counts were conducted in 1989, 1992-1994, or 1996-2017.

Replicate 1988 1990 1991 1995 2018

1 203 365 269 152 261 2 198 356 276 278 273 3 187 367 308 256 - 4 164 362 297 261 - 5 205 337 349 239 - 6 - - 367 223 - 7 - - 317 318 -

Mean 191 357 312 247 267 n 5 5 7 7 2


24

Table 10. Numbers of black-legged kittiwakes counted on land-based index plots at Cape Thompson, Alaska in 2018.

Date 3-Aug 4-Aug Plot 2018 2018 Notes (Notes in italics are quoted from the summary data sheets.)

3-1A 1 NCa Plot couldn't be counted from the location at which the previous photos were taken (1988) due to beach erosion. 3-2B 48 NC Plot couldn't be counted from the location at which the previous photos were taken (1988) due to beach erosion. 3-2C 20 NC Plot couldn't be counted from the location at which the previous photos were taken (1988) due to beach erosion. 3-2D 51 NC New plot established in 2018. 4-1A 122 82 4-1B 44 66 4-2C 246 252 4-3D 86 82 “Rebar marker at lower end of tall grass patch” 4-4E 256 256 5-1A 12 14 "Potential for missing birds on far left edge." 5-1B 132 140 "Has lost some cliff but can see fine." 5-1C 16 19 "Lower and right portion not visible." 5-1D 1 2 "Right-hand portion of Fadely's plot not visible." 5-2E 2 3 5-2F 2 2 5-2F' 0 0 5-2G 99 98 5-3H 0 0 5-3H' 0 0 5-4I 4 5 5-5J 57 68 "Swartz L." 5-6K 1 2 "Swartz M." (Swartz Plot M includes Fadely Plot 5-6K plus Plot 5-K’). 5-6K' 0 0 "Swartz M." (Swartz Plot M includes Fadely Plot 5-6K plus Plot 5-K’). 5-7L 10 NC 5-7L' 12 NC 5-8-M NC 82 5-8N 23 38 Swartz Q. 5-8N' 2 2 Swartz Q.


25

Figure 8. Numbers of black-legged kittiwakes counted on land-based Swartz index plots 5G, 5L, 5M, 5N, 5P, and 5Q at Cape Thompson, Alaska. No counts were conducted in 1980-1989, 1992-1994, or 1996-2017. Error bars represent one standard deviation.

0

100

200

300

400

500

600

79 81 83 85 87 89 91 93 95 97 99 01 03 05 07 09 11 13 15 17

Num

ber o

f kitt

iwak

es

Year

26

Table 11. Numbers of black-legged kittiwakes counted on land-based Swartz index plots 5G, 5L, 5M, 5N, 5P, and 5Q at Cape Thompson, Alaska. No counts were conducted in 1961-1978, 1980, 1981, 1983-1989, 1992-1994, or 1996-2017.

Replicate 1979a 1990a 1991a 1995a 2018

1 366 492 433 304 438 2 - 499 - 347 461 3 - - - 358 - 4 - - - 304 - 5 - - - 406 - 6 - - - 405 - 7 - - - 424 -

Mean 366 496 433 364 450 n 1 2 1 7 2

SD - 5 - 49 16 First count 5 Aug 21 Jul 31 Jul 15 Jul 3 Aug Last count - 28 Jul - 14 Aug 4 Aug

a Data are from Roseneau et al. 2000; Table 25.

27

Table 12. Numbers of black-legged kittiwakes counted on land-based Swartz index plots at Cape Thompson, Alaska in 2018.

Date 3-Aug 4-Aug

Plot 2018 2018 Notes

Swartz 5G 59 76 Swartz 5L 57 68 Fadely plot 5-5J Swartz 5M 1 2 Fadely plot 5-6K plus 5-6K' Swartz 5N 88 87 Swartz 5O 11 11 Swartz 5P 208 188 Swartz 5Q 25 40 Fadely 5-8N plus 5-8N'

Table 13. Numbers of black-legged kittiwakes counted from photographs of land-based plots at Cape Thompson, Alaska. Photographs were taken on 3 August 2018.

Plot Birds Notes

4-1A 112

4-1B 40

4-2C 318

4-3D 98

4-4E 237

5-1A 33

5-1B 86

5-1C 11

5-1D 1

5-2E 1 Photo quite far, zooming in a lot creates blurry image.

5-2F 3 Photo quite far, zooming in a lot creates blurry image.

5-2G 132 Photo quite far, zooming in a lot creates blurry image.

5-3H 0

5-4I 4

5-5J 66

Swartz 5-M 1

5-6K 3 Slightly blurry

5-7L 24

5-8M 86 Blurry

Swartz 5-Q 33

Swartz 5-G 52 Photo did not include all of the plot, blurry

Swartz 5-N 79

Swartz 5-O 13

Swartz 5-P 199

28

Table 14. Numbers of black-legged kittiwakes counted manually and from photographs of land-based plots at Cape Thompson, Alaska in 2018. Photographs were taken and counts were conducted on the same day (3 August 2018). Manual counts were made within 10 minutes of the time when the photographs were taken.

Plot Manual Count Mean on 3 Aug. (Birds) Photo Count (Birds)

4-1A 122 112 4-1B 44 40 4-2C 246 318 4-3D 86 98 4-4E 256 237 5-1A 12 33 5-1B 132 86 5-1C 16 11 5-1D 1 1 5-2E 2 1 5-2F 2 3 5-2G 99 132 5-3H 0 0 5-4I 4 4


5-6K 1 3 5-7L 22 24 5-8M NCa 86



29

Table 15. Numbers of black-legged kittiwake nests counted on land-based index plots at Cape Thompson, Alaska in 2018.

Date 3-Aug 4-Aug Maximum Plot 2018 2018 Count Notes (Notes in italics are quoted from the summary data sheets.)

3-1A 2 NCa 2 Plot couldn't be counted from the location at which the previous photos were taken (1988) due to beach erosion. 3-2B 27 NC 27 Plot couldn't be counted from the location at which the previous photos were taken (1988) due to beach erosion. 3-2C 18 NC 18 Plot couldn't be counted from the location at which the previous photos were taken (1988) due to beach erosion. 3-2D 43 NC 43 New plot established in 2018. 4-1A 49 45 49 4-1B 46 18 46 4-2C 104 119 119 4-3D 33 42 42 “Rebar marker at lower end of tall grass patch” 4-4E 135 160 160 5-1A 6 6 6 "Potential for missing birds on far left edge." 5-1B 51 63 63 "Has lost some cliff but can see fine." 5-1C 14 12 14 "Lower and right portion not visible." 5-1D 1 1 1 "Right-hand portion of Fadely's plot not visible." 5-2E 1 1 1 5-2F 2 1 2 5-2F' 0 0 0 5-2G 67 55 67 5-3H 0 0 0 5-3H' 0 0 0 5-4I 2 3 3 5-5J 36 48 48 "Swartz L." 5-6K 1 1 1 "Swartz M." (Swartz Plot M includes Fadely Plot 5-6K plus Plot 5-K’). 5-6K' 0 0 0 "Swartz M." (Swartz Plot M includes Fadely Plot 5-6K plus Plot 5-K’). 5-7L 9 NC 9 5-7L' 7 NC 7 5-8-M NC 43 43 5-8N 21 25 25 Swartz Q. 5-8N' 2 2 2 Swartz Q.


30

Table 16. Numbers of black-legged kittiwake nests counted on land-based Swartz index plots at Cape Thompson, Alaska in 2018.

Date 3-Aug 4-Aug Maximum

Plot 2018 2018 Count Notes

Swartz 5G 38 51 51 Swartz 5L 36 48 48 Fadely plot 5-5J Swartz 5N 66 47 66 Swartz 5M 1 1 1 Fadely plot 5-6K plus 5-6K' Swartz 5O 6 5 6 Swartz 5P 101 128 128 Swartz 5Q 23 27 27 Fadely 5-8N plus 5-8N'

Table 17. Numbers of black-legged kittiwake nests counted from photographs of land-based plots at Cape Thompson, Alaska. Photographs were taken on 3 August 2018.

Plot Nests Notes

4-1A 46

4-1B 16

4-2C 118

4-3D 38

4-4E 161

5-1A 17

5-1B 52

5-1C 8

5-1D 1

5-2E 0 Photo quite far, zooming in a lot creates blurry image.

5-2F 1 Photo quite far, zooming in a lot creates blurry image.

5-2G 58 Photo quite far, zooming in a lot creates blurry image.

5-3H 0

5-4I 3

5-5J 49

Swartz 5-M 0

5-6K 2 Slightly blurry

5-7L 19

5-8M 67 Blurry

Swartz 5-Q 27

Swartz 5-G 35 Photo did not include all of the plot, blurry

Swartz 5-N 69

Swartz 5-O 12

Swartz 5-P 102

31

Table 18. Numbers of black-legged kittiwake nests counted manually and from photographs of land-based plots at Cape Thompson, Alaska in 2018. Photographs were taken and counts were conducted on the same day (3 August 2018). Manual counts were made within 10 minutes of the time when the photographs were taken.

Plot Manual Count Mean on 3 Aug. (Nests) Photo Count (Nests)

4-1A 49 46 4-1B 46 16 4-2C 104 118 4-3D 33 38 4-4E 135 161 5-1A 6 17 5-1B 51 52 5-1C 14 8 5-1D 1 1 5-2E 1 0 5-2F 2 1 5-2G 67 58 5-3H 0 0 5-4I 2 3


5-6K 1 2 5-7L 16 19 5-8M NCa 67



32

Figure 9. Numbers of murres (species combined) counted on boat-based index plots at Colony 4, Cape Thompson, Alaska. No counts were conducted in 1962-1975, 1978, 1980-1981, 1983-1987, 1989, 1991-1994, or 1996-2017. Error bars represent one standard deviation.

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

60 64 68 72 76 80 84 88 92 96 00 04 08 12 16

Mea

n nu

mbe

r of m

urre

s

Year

33

Table 19. Numbers of murres (species combined) counted on boat-based index plots at Colony 4, Cape Thompson, Alaska. No counts were conducted in 1962-1975, 1978, 1980-1981, 1983-1987, 1989, 1991-1994, or 1996-2017.

Date(s) 15 Jul & 25 Jul & 17-Jul 22-Jul 9-Aug 12-Aug 7-Aug 14-Aug 28-Jul 3-Aug 3-Aug 25-Jul 3-Aug 28-Jul 10-Aug 1-Aug 2-Aug

Plot 1960a 1961a 1976a 1977a 1979a 1979a 1982a 1982a 1988a 1990a 1990a 1995a 1995a 2018 2018

4A 133 73 138 158 123 182 110 110 64 82 82 68 60 12 57 4B 639 527 265 548 585 572 245 180 310 109 182 285 330 184 266 4C 835 369 910 975 225 278 375 490 195 315 315 365 260 115 175

4D+E 1562 1402 1045 1120 986 973 765 805 685 564 780 895 625 387 492 4F+G 2156 1656 1248 1323 757 1282 1180 805 810 840 841 1,073 1,040 125 434

4H 348 351 375 347 370 317 385 170 247 331 330 450 375 37 169 4I 58 45 40 95 48 75 65 85 60 53 45 15 22 0 42 4J 425 199 804 560 435 627 490 490 545 407 739 780 595 155 345 4K 206 NCb 135 125 160 102 95 110 60 69 124 47 115 17 113 4L 171 165 125 420 295 282 405 245 215 312 251 227 295 62 133 4M 836 485 569 488 301 492 390 335 307 163 360 495 355 75 431 4N 281 184 327 324 335 362 395 195 230 277 292 655 450 138 384 4O 1 20 108 98 101 105 90 75 70 100 80 110 98 24 100 4P 614 499 490 658 485 692 660 375 255 402 553 750 560 539 590 4Q 172 155 260 165 70 218 240 275 245 258 367 260 240 170 502 4R 124 92 57 220 190 290 240 235 165 252 304 350 200 133 238

Replicate Totalc 8355 6222 6761 7499 5306 6747 6035 4870 4403 4465 5521 6778 5505 2156 4358

Mean = 6027 Mean = 5453 Mean = 4993 Mean = 6142 Mean = 3257 SDd = 1019 SD = 824 SD = 747 SD = 900 SD = 1557

a Data are from Roseneau et al. 2000; Table 28. b NC = Plot not counted. c Plot 4K was not included in the replicate total, having not been counted in 1961. dSD = Standard deviation.

34

Table 20. Numbers of murres (species combined) counted from photographs of boat-based plots at Colony 4, Cape Thompson, Alaska. Photographs were taken on 1 August 2018.

Plot Birds Notes

4-4R 94 Zooming in creates blurry image, difficult to get accurate count 4-4Q 249 Zooming in creates blurry image, difficult to get accurate count 4-4P 299 Zooming in creates blurry image, difficult to get accurate count 4-4N 159 Zooming in creates blurry image, difficult to get accurate count 4-4M 160 Zooming in creates blurry image, difficult to get accurate count 4-4O 43 Zooming in creates blurry image, difficult to get accurate count 4-4L 57 Zooming in creates blurry image, difficult to get accurate count 4-4K 49 Zooming in creates blurry image, difficult to get accurate count 4-4J 241 Zooming in creates blurry image, difficult to get accurate count 4-4H 142 Zooming in creates blurry image, difficult to get accurate count 4-4I 9 Zooming in creates blurry image, difficult to get accurate count 4-4F 144 Zooming in creates blurry image, difficult to get accurate count 4-4G 423 Zooming in creates blurry image, difficult to get accurate count 4-4E 445 Zooming in creates blurry image, difficult to get accurate count 4-4C 344 Zooming in creates blurry image, difficult to get accurate count 4-4B 233 Zooming in creates blurry image, difficult to get accurate count 4-4A 42 Zooming in creates blurry image, difficult to get accurate count

35

Table 21. Numbers of murres (species combined) counted manually and from photographs of boat-based index plots at Colony 4, Cape Thompson, Alaska. Photographs were taken and counts were conducted on the same day (1 August 2018).

Plot Manual Count (Birds) Photo Count (Birds) 4-4R 133 94 4-4Q 170 249 4-4P 539 299 4-4N 138 159 4-4M 75 160 4-4O 24 43 4-4L 62 57 4-4K 17 49 4-4J 155 241 4-4H 37 142 4-4I 0 9 4-4F 125a 144 4-4G 423 4-4Eb 387 445 4-4C 115 344 4-4B 184 233 4-4A 12 42

a Plots 4-4F and 4-4G were combined during the 2018 murre count. b Plots 4-4D and 4-4E were combined during the 2018 count. Plot 4-4D eroded

to the point that it is essentially gone.

36

Figure 10. Numbers of black-legged kittiwakes counted on boat-based index plots at Colony 4, Cape Thompson, Alaska. No counts were conducted in 1961-1975, 1980-1981, 1983-1987, 1989, 1991-1994, or 1996-2017. Error bars represent one standard deviation.

0

1000

2000

3000

4000

5000

6000

7000

60 64 68 72 76 80 84 88 92 96 00 04 08 12 16

Mea

n nu

mbe

r of k

ittiw

akes

Year

37

Table 22. Numbers of black-legged kittiwakes counted on boat-based index plots at Colony 4, Cape Thompson, Alaska. No counts were conducted in 1961-1975, 1980-1981, 1983-1987, 1989, 1991-1994, or 1996-2017.

Date(s) 18 Aug & 15-Jul 9-Aug 19-Aug 14-Aug 10-Jul 5-Aug 10-Aug 25-Jul 3-Aug 28-Jul 1-Aug 2-Aug

Plot 1960a 1976a 1977a 1978a 1979a 1982a 1988a 1990a 1990a 1995a 2018 2018

4A 472 121 430c

249 156 285 219 516 492 118 200 224

4B 614 80 284 368 325 414 397 396 237 273 411 4C 750 266 289 383 326 405 125 449 742 164 121 178

4D 76 15 404d 22 0 56 14 71 85 299d 886d 653d 4E 1128 265 479 366 512 559 750 799

4F 894b 79 421b 175 170 245 195 1049b 315 154 68 164

4G 155 380 375 406 440 734 236 79 448 4H 224 107 284 177 144 134 130 270 291 112 85 208 4I 506 146 102 324 345 395 285 508 437 213 266 349 4J 328 96 101 116 134 76 153 131 81 124 132 4K 292 87 105 185 166 122 224 186 135 162 136 4L 410 69 198 185 233 146 324 284 152 218 247 4M 170 50 125 116 123 65 165 129 72 130 151 4N 298 75 174 176 219 140 292 316 146 291 248 4O 16 11 293e 28 50 48 25 90 116 24 89 81 4P 86 27 80 89 109 83 173 132 76 239 226 4Q 0 0 NCf 4 9 10 17 60 41 16 124 76 4R 0 0 238g 2 2 0 6 7 2 2 72 71

Replicate Totalh 6264 1649 2461 3286 3169 3795 3044 5438 5587 2221 3303 3927

Mean = 5513 Mean = 3615 SDh = 105 SD = 441

a Data are from Roseneau et al. 2000; Table 23. b Plots 4F and 4G combined. c Plots 4A and 4B combined. d Plots 4D and 4E combined. e Plots 4J, 4K, 4L, and 4O combined. f NC = Plot not counted. g Plots 4M, 4N, 4P, and 4R combined. h Plot 4Q was not included in the replicate total, having not been counted in 1977. I SD= Standard deviation.

38

Table 23. Numbers of black-legged kittiwakes counted from photographs of boat-based plots at Colony 4, Cape Thompson, Alaska. Photographs were taken on 1 August 2018.

Plot Birds Notes

4-4R 51 Zooming in creates blurry image, difficult to get accurate count

4-4Q 122 Zooming in creates blurry image, difficult to get accurate count

4-4P 195 Zooming in creates blurry image, difficult to get accurate count

4-4N 263 Zooming in creates blurry image, difficult to get accurate count

4-4M 129 Zooming in creates blurry image, difficult to get accurate count

4-4O 66 Zooming in creates blurry image, difficult to get accurate count

4-4L 231 Zooming in creates blurry image, difficult to get accurate count

4-4K 173 Zooming in creates blurry image, difficult to get accurate count

4-4J 165 Zooming in creates blurry image, difficult to get accurate count

4-4H 147 Zooming in creates blurry image, difficult to get accurate count

4-4I 307 Zooming in creates blurry image, difficult to get accurate count

4-4F 272 Zooming in creates blurry image, difficult to get accurate count

4-4G 620 Zooming in creates blurry image, difficult to get accurate count

4-4E 651 Zooming in creates blurry image, difficult to get accurate count

4-4C 422 Zooming in creates blurry image, difficult to get accurate count

4-4B 688 Zooming in creates blurry image, difficult to get accurate count

4-4A 264 Zooming in creates blurry image, difficult to get accurate count

39

Table 24. Numbers of black-legged kittiwakes counted manually and from photographs of boat-based index plots at Colony 4, Cape Thompson, Alaska. Photographs were taken and counts were conducted on the same day (1 August 2018).

Plot Manual Count (Birds) Photo Count (Birds) 4-4R 72 51 4-4Q 124 122 4-4P 239 195 4-4N 291 263 4-4M 130 129 4-4O 89 66 4-4L 218 231 4-4K 162 173 4-4J 124 165 4-4H 85 147 4-4I 266 307 4-4F 68 272 4-4G 79 620 4-4Ea 886 651 4-4C 121 422 4-4B 273 688 4-4A 200 264

a Plots 4-4D and 4-4E were combined during the 2018 count. Plot 4-4D eroded to the point that it is essentially gone.

40

Figure 11. Numbers of black-legged kittiwake nests counted on boat-based index plots at Colony 4, Cape Thompson, Alaska (maximum nest count was used in 2018). No counts were conducted in 1962-1977, 1980-1981, 1983-1987, or 1989-2017.

0

500

1000

1500

2000

2500

3000

3500

61 65 69 73 77 81 85 89 93 97 01 05 09 13 17

Num

ber o

f kitt

iwak

e ne

sts

Year

41

Table 25. Numbers of black-legged kittiwake nests counted on boat-based index plots at Colony 4, Cape Thompson, Alaska. No counts were conducted in 1961-1975, 1980-1981, 1983-1987, 1989, 1991-1994, or 1996-2017.

Date(s) 29-Jul & 3 Aug 14-Aug 10 & 19-

Jul 5-Aug 10-Aug 1-Aug 2-Aug MAX

Plot 1961a 1978b 1979c 1982d 1988e 2018 2018 2018f

4A 176 111 110 185 192 90 114 114 4B 272 97 375 216 370 123 215 215 4C 361 136 152 287 129 61 114 114

4D/E 437 316 500 408 383 280 367 367 4F 223 120 135 187 158 29 108 108 4G 471 207 422 305 317 34 237 237 4H 107 84 107 91 102 33 72 72 4I 300 112 282 265 247 62 119 119 4J 132 55 93 77 56 48 37 48 4K 142 62 139 112 117 64 79 79 4L 160 71 176 152 118 116 79 116 4M 81 53 89 81 60 52 50 52 4N 156 132 167 149 150 66 113 113 4O 10 18 30 27 24 26 32 32 4P 40 53 76 63 78 136 107 136 4Q 0 2 7 4 20 71 48 71 4R 0 2 1 0 8 41 32 41

Total 3068 1631 2861 2609 2529 2034

a Data are from Fadely et al. 1989; Table G.55. b Data are from Fadely et al. 1989; Table G.58. c Data are from Fadely et al. 1989; Table G.59. d Data are from Fadely et al. 1989; Table G.60. e Data are from Fadely et al. 1989; Table G.61. f 2018 maximum nest count was used for comparisons.

42

Table 26. Numbers of black-legged kittiwake nests counted from photographs of boat-based plots at Colony 4, Cape Thompson, Alaska. Photographs were taken on 1 August 2018.

Plot Nests Notes

4-4R 31 Zooming in creates blurry image, difficult to get accurate count

4-4Q 65 Zooming in creates blurry image, difficult to get accurate count

4-4P 116 Zooming in creates blurry image, difficult to get accurate count

4-4N 131 Zooming in creates blurry image, difficult to get accurate count

4-4M 63 Zooming in creates blurry image, difficult to get accurate count

4-4O 39 Zooming in creates blurry image, difficult to get accurate count

4-4L 133 Zooming in creates blurry image, difficult to get accurate count

4-4K 123 Zooming in creates blurry image, difficult to get accurate count

4-4J 99 Zooming in creates blurry image, difficult to get accurate count

4-4H 67 Zooming in creates blurry image, difficult to get accurate count

4-4I 140 Zooming in creates blurry image, difficult to get accurate count

4-4F 141 Zooming in creates blurry image, difficult to get accurate count

4-4G 244 Zooming in creates blurry image, difficult to get accurate count

4-4E 313 Zooming in creates blurry image, difficult to get accurate count

4-4C 208 Zooming in creates blurry image, difficult to get accurate count

4-4B 365 Zooming in creates blurry image, difficult to get accurate count

4-4A 126 Zooming in creates blurry image, difficult to get accurate count

43

Table 27. Numbers of black-legged kittiwake nests counted manually and from photographs of boat-based index plots at Colony 4, Cape Thompson, Alaska. Photographs were taken and counts were conducted on the same day (1 August 2018).

Plot Manual Count (Nests) Photo Count (Nests) 4-4R 41 31 4-4Q 71 65 4-4P 136 116 4-4N 66 131 4-4M 52 63 4-4O 26 39 4-4L 116 133 4-4K 64 123 4-4J 48 99 4-4H 33 67 4-4I 62 140 4-4F 29 141 4-4G 34 244 4-4Ea 280 313 4-4C 61 208 4-4B 123 365 4-4A 90 126

a Plots 4-4D and 4-4E were combined during the 2018 count. Plot 4-4D eroded to the point that it is essentially gone.

44

Table 28. Locations (latitude, longitude) of endpoints of seabird colonies at Cape Thompson, Alaska (WGS 84).

Colony Eastern end point Western end point

1 68.09861⁰ N, -165.80456⁰ W 68.10235⁰ N, -165.81784⁰ W 2 68.10577⁰ N, -165.85312⁰ W 68.11750⁰ N, -165.90397⁰ W 3 68.12993⁰ N, -165.94596⁰ W 68.13758⁰ N, -165.97140⁰ W 4 68.14081⁰ N, -165.97536⁰ W 68.14553⁰ N, -165.98247⁰ W 5 68.14553⁰ N, -165.98247⁰ W 68.15807⁰ N, -165.99591⁰ W

Table 29. Locations (latitude, longitude) of observation points for land-based plots at Cape Thompson, Alaska (WGS 84).

Observation Post

Location

Plots counted from the Observation Post

4-1 68.14209⁰ N, -165.97695⁰ W 4-1A, 4-1B 4-2 68.14236⁰ N, -165.97765⁰ W 4-2C 4-3 68.14283⁰ N, -165.97987⁰ W 4-3D 4-4 68.14417⁰ N, -165.98093⁰ W 4-4E 5-1a 68.14596⁰ N, -165.97874⁰ W 5-1A, 5-1B, 5-1C, 5-1D 5-2 68.14710⁰ N, -165.97940⁰ W 5-2E, 5-2F, 5-2F’, 5-2G 5-3 68.14773⁰ N, -165.98012⁰ W 5-3H, 5-3H’, Swartz 5G 5-4 68.14809⁰ N, -165.98093⁰ W 5-4I 5-5 68.14850⁰ N, -165.98062⁰ W 5-5J, Swartz 5L (same plot as 5-5J) 5-6 68.14877⁰ N, -165.98047⁰ W 5-6K, 5-6K’, Swartz 5-M (same plot as 5-6K plus 5-6K’), Swartz 5N, Swartz 5O, Swartz 5P

Swartz 5-6 68.14771⁰ N, -165.97983⁰ W Swartz 5-M. Plots 5-6K + 5-6K’ but counted from a slightly different observation point. 5-7 68.14919⁰ N, -165.98030⁰ W 5-7L, 5-7L’ 5-8 68.14962⁰ N, -165.98111⁰ W 5-8M, 5-8N, 5-8N’, Swartz 5Q (same plot as 5-8N plus 5-8N’)

a See notes in Table 3 regarding ability to see plots from this observation post.

45

Table 30. Locations (latitude, longitude) of midpoints of boat-based plots at Cape Lisburne, Alaska (WGS 84).

Plot Location

11 68.85045⁰N, -166.21787⁰W 12 68.85059⁰ N, -166.21812⁰ W 25 68.86113⁰ N, -166.22567⁰ W 26 68.86136⁰ N, -166.22604⁰ W 30 68.86294⁰ N, -16622900⁰ W 32 68.86434⁰ N, -16622962⁰ W 65 68.88303⁰ N, -166.20009⁰ W 66 68.88224⁰ N, -166.19514⁰ W 70 68.88099⁰ N, -166.18708⁰ W 72 68.88080⁰ N, -166.18464⁰ W

72/73a 68.88063⁰ N, -166.18069⁰ W 74 68.88040⁰ N, -166.17708⁰ W

a Boundary between plots 72 and 73.

SURVEYS OF LEDGE-NESTING SEABIRDS AT …...AMNWR 2019/06 SURVEYS OF LEDGE-NESTING SEABIRDS AT SELECTED SITES IN THE NORTHERN BERING SEA AND EASTERN CHUKCHI SEA, JULY-AUGUST 2018 Donald

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