Columbia Plateau

Weekly Update for 8/27 – 9/2/2012

Sites on the Columbia Plateau not visited

Weekly Update for 8/20 – 8/26/2012

Sites on the Columbia Plateau not visited

Weekly Update for 8/13 – 8/19/2012

8/15/12 ›

Salmonid smolt PIT tag recovery at piscivorous waterbird colonies on the Columbia Plateau is temporarily completed; PIT tag recovery will resume at the Badger Island American white pelican colony, Foundation Island double-crested cormorant colony, and North Potholes double-crested cormorant colony when birds are no longer attending those colonies

8/13 – 8/14/12 ›

Salmonid smolt PIT tag recovery conducted on gull colony at Crescent Island in the mid-Columbia River

Weekly Update for 8/6 – 8/12/2012

8/12/12 ›

Salmonid smolt PIT tag recovery initiated on gull colony at Crescent Island in the mid-Columbia River

8/9 – 8/11/12 ›

Salmonid smolt PIT tag recovery conducted on gull colony at Miller Rocks in the mid-Columbia River

8/7/12 ›

Salmonid smolt PIT tag recovery conducted on Caspian tern and double-crested cormorant colonies at Harper Island in Sprague Lake, WA

8/6/12 ›

Salmonid smolt PIT tag recovery conducted on Caspian tern colony at Twining Island in Banks Lake, WA

Weekly Update for 7/30 – 8/5/2012

8/4 – 8/5/12 ›

Salmonid smolt PIT tag recovery conducted on Caspian tern colony at Goose Island in Potholes Reservoir

8/2 – 8/3/12 ›

Salmonid smolt PIT tag recovery conducted on Caspian tern colony at Crescent Island in the mid-Columbia River

8/2/12 ›

Salmonid smolt PIT tag recovery commenced at various piscivorous waterbird colonies in the Columbia Plateau region

Weekly Update for 7/23 – 7/29/2012

7/23 – 7/29/12 ›

Final week of regular monitoring of piscivorous waterbird colonies in the Columbia Plateau region during 2012

7/25/12 ›

Survey of North Potholes double-crested cormorant colony; 143 cormorants and 101 attended cormorant nests (some with fledglings) counted on colony; significant nest failure has occurred at this colony this breeding season; cause(s) of major nest failure at this cormorant colony, the largest in the Columbia Plateau region, remain a mystery

7/25/12 ›

Survey of Badger Island on the mid-Columbia River; 154 American white pelicans (both adults and fledglings), 16 double-crested cormorants (both adults and juveniles), and about 700 California gulls (both adults and juveniles) were counted on the island; all previous nesting attempts by Caspian terns on Badger Island in 2012 have failed; the possible causes of colony failure include nest predation, flooding of part of the colony during high water, and decline in food availability as the salmonid out-migration winds down

7/23 – 7/29/12 ›

High counts this week of 31 Caspian terns (down from 111 last week) and 4 tern chicks (down from 17 last week) on the Crescent Island colony; declining chick counts over the past several weeks were likely due to chicks fledging and loafing near the water during periods of high temperatures; California gulls, ring-billed gulls, great egrets, great blue herons, and black-crowned night-herons also nested and were successful in rearing young on Crescent Island this season

7/23 – 7/29/12 ›

High count of 7 attended nests on the double-crested cormorant colony at Foundation Island, down from 28 attended nests last week; numerous cormorant fledglings observed on or near the colony; great blue herons also nested and were successful in rearing young on Foundation Island this season

7/23 – 7/29/12 ›

All remaining Caspian terns raised at the colony on Goose Island in Potholes Reservoir have fledged; California gulls, ring-billed gulls, and Canada geese also nested and were successful in rearing young on Goose Island-Potholes this season

Weekly Update for 7/16 – 7/22/2012

7/20/12 ›

Survey of Harper Island in Sprague Lake on the Columbia Plateau off the mid-Columbia River; 347 double-crested cormorants (both adults and fledglings), 175 gulls (both California and ring-billed gulls), one great blue heron, and one black-crowned night-heron were counted on the island; previously active Caspian tern nests on Harper Island all appear to have failed, cause unknown; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at Harper Island and none were detected

7/18/12 ›

Survey of North Potholes double-crested cormorant colony; 228 cormorants and 122 attended cormorant nests (some with fledglings) counted on colony; significant nest failure has occurred at this colony this breeding season; cause(s) of major nest failure at this cormorant colony, the largest in the Columbia Plateau region, remain a mystery

7/17/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; minimum counts of 1,319 California gulls (adults and juveniles), 4 ring-billed gulls (adults and juveniles), and 2 adult double-crested cormorants on island

7/17/12 ›

Survey of piscivorous waterbird colonies in Blalock Islands, mid-Columbia River; all previous nesting attempts by Caspian terns in the Blalock Islands have failed this season; minimum count of about 675 California gulls (adults and juveniles) on Anvil Island; 166 California gulls (adults and juveniles) and 22 adult American while pelicans on the sand bar between Anvil and Sand islands; minimum counts of 81 California gulls (mostly adults), 18 adult Caspian terns, 18 juvenile great blue herons, 13 juvenile black-crowned night-herons, and 8 great egrets (adults and juveniles) on Sand Island; minimum count of 148 ring-billed gulls (adults and juveniles), 30 California gulls (adults and juveniles), and 5 adult American white pelicans on Straight Six Island

7/16/12 ›

Survey of Badger Island on the mid-Columbia River; 313 American white pelicans (both adults and fledglings), 12 adult double-crested cormorants, and 4 California gulls (both adults and juveniles) were counted on island; all previous nesting attempts by Caspian terns on Badger Island in 2012 have failed; the possible causes of colony failure include nest predation, flooding of part of the colony during high water, and decline in food availability as the salmonid out-migration winds down

7/16/12 ›

Sixteenth boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 169 pelicans, 138 cormorants, and 9 terns counted on Columbia River; a total of 49 pelicans, 19 cormorants, and 4 terns counted on Snake River

7/16 – 7/22/12 ›

High count of 111 Caspian terns on the Crescent Island colony this week, down from 126 last week; high count of 18 attended nests this week, down from 52 nests last week; the number of tern chicks counted on-colony decreased throughout the week, from 17 chicks (on 7/16) to 10 chicks (on 7/20); declining chick counts over the past several weeks were likely due to chicks fledging and loafing near the water during periods of high temperatures; California gulls, ring-billed gulls, great egrets, great blue herons, and black-crowned night-herons also nested and were successful in rearing young on Crescent Island this season

7/16 – 7/22/12 ›

High count of 28 attended nests on the double-crested cormorant colony at Foundation Island, down from 62 attended nests last week; numerous cormorant fledglings observed on or near the colony; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at Foundation Island and none were detected; great blue herons also nested and were successful in rearing young on Foundation Island this season

7/16 – 7/22/12 ›

High count of 2 Caspian terns on the Goose Island-Potholes Reservoir colony this week, down from 51 terns last week; there were no attended tern nests on Goose Island by the end of the week, as all the remaining tern chicks have fledged; California gulls, ring-billed gulls, and Canada geese also nested and were successful in rearing young on Goose Island-Potholes this season

Weekly Update for 7/9 – 7/15/2012

7/13/12 ›

Survey of Banks Lake on the Columbia Plateau off the mid-Columbia River; about 900 nesting California gulls (with chicks) and 33 Caspian terns were counted on Twining Island; also observed on Twining Island was one banded juvenile Caspian tern (banded at Goose Island-Potholes Reservoir earlier this season); all earlier Caspian tern nesting attempts on Twining Island have apparently failed; on nearby Goose Island about 440 nesting ring-billed gulls (with chicks), 170 nesting California gulls (with chicks), 2 nesting great blue herons (with chicks), and 11 loafing American white pelicans were counted

7/13/12 ›

Survey of Okanogan double-crested cormorant colony; 25 adult double-crested cormorants and 23 attended cormorant nests counted (some with chicks); nearby were 5 adult great blue herons (5 active nests, some with chicks)

7/12/12 ›

Cindy Boen, Marvin Shutters, and Tim Fleeger with the U.S. Army Corps of Engineers - Walla Walla District visited the Caspian tern colony on Goose Island-Potholes Reservoir

7/11/12 ›

Survey of Badger Island American white pelican colony; 137 adults and 71 juveniles counted on or near island; pelicans nesting on both the upstream and mid-island sub-colonies

7/11/12 ›

Survey of recently formed Badger Island Caspian tern colony; 32 loafing Caspian terns observed on island this week; all previous nesting attempts by Caspian terns on Badger Island in 2012 have failed; the possible causes of colony failure include nest predation, flooding of part of the colony during high water last week, and decline in food availability as the salmonid out-migration winds down

7/11/12 ›

Fifteenth boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 229 cormorants, 78 pelicans, and 50 terns counted on Columbia River; a total of 87 pelicans, 33 cormorants, and 3 terns counted on Snake River

7/11/12 ›

Survey of North Potholes double-crested cormorant colony; 218 cormorants and 153 attended cormorant nests (some with fledglings) counted on colony; significant nest failure has occurred at this colony this breeding season; cause(s) of major nest failure at this cormorant colony, the largest in the Columbia Plateau region, remain a mystery

7/10/12 ›

Survey of piscivorous waterbird colonies in Blalock Islands, mid-Columbia River; all previous nesting attempts by Caspian terns in the Blalock Islands have failed this season; minimum count of about 930 nesting California gulls (some with chicks) on Anvil Island; 120 loafing California gulls (adults and juveniles), 8 loafing American while pelicans, and one loafing Caspian tern on the sand bar between Anvil and Sand islands; minimum counts of 8 great blue heron nests (with chicks), 8 great egret nests (with chicks), 18 loafing Caspian terns, and 3 juvenile black-crowned night-herons on Sand Island; minimum count of 237 nesting ring-billed gulls (some with chicks), 34 loafing California gulls, and one loafing Caspian tern on Straight Six Island

7/10/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; minimum counts of 1,650 nesting California gulls (ca. 965 active nests, some with fledglings), 10 nesting ring-billed gulls (2 active nests and at least 2 chicks), 4 loafing double-crested cormorants, and one loafing American white pelican on island

7/9 – 7/15/12 ›

High count of 126 Caspian terns on the Crescent Island colony this week, down from 298 last week; high count of 52 attended nests this week, down from 80 nests last week; the number of tern chicks counted on-colony decreased throughout the week, from 50 chicks (on 7/9) to 30 chicks (on 7/13); declining chick counts this week were likely due to chicks fledging and loafing near the water during periods of high temperatures; California gulls, ring-billed gulls, great egrets, great blue herons, and black-crowned night-herons also nested and were successful in rearing young on Crescent Island this season

7/9 – 7/15/12 ›

High count of 62 attended nests on the double-crested cormorant colony at Foundation Island, down from 107 attended nests last week; numerous cormorant fledglings observed on or near the colony; 4 nesting great blue herons (with chicks), 135 loafing California gulls, 21 loafing American white pelicans, 5 loafing Caspian terns, and one loafing black-crowned night-heron also counted on island

7/9 – 7/15/12 ›

High count of 51 Caspian terns on the Goose Island-Potholes Reservoir colony this week, down from 149 terns last week; high count of 4 attended tern nests this week, down from 36 nests last week; the number of tern chicks counted on colony declined dramatically this week (from 33 last week to 3 this week); declining counts of adults and chicks on colony were likely due to chicks fledging and adults loafing near the water during periods of high temperatures; minimum of 945 gulls, mostly nesting California and ring-billed gulls and some with fledglings, were also counted on the island

Weekly Update for 7/2 – 7/8/2012

7/6/12 ›

Survey of piscivorous waterbird colonies in Blalock Islands, mid-Columbia River; minimum count of about 937 nesting California gulls (some with chicks) and 6 loafing ring-billed gulls on Anvil Island; 1 loafing American while pelican and 22 loafing California gulls on sand bar between Anvil and Sand islands; minimum counts of 5 great blue heron nests (with chicks), 6 great egret nests (with chicks), 21 loafing Caspian terns, and 107 loafing California gulls on Sand Island; minimum count of 228 nesting ring-billed gulls on Straight Six Island (some with chicks); three previously active Caspian tern nests on sand bar between Anvil and Sand islands have failed (cause unknown)

7/6/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; minimum counts of 1,790 nesting California gulls (ca. 975 active nests, some with fledglings), 12 nesting ring-billed gulls (4 active nests and at least 8 chicks), and 7 loafing double-crested cormorants on island

7/5/12 ›

People observed walking on Goose Island-Potholes Reservoir Caspian tern colony; last remaining tern nest on east side of island was depredated during disturbance; terns nesting on west side of island were not disturbed

7/5/12 ›

Survey of Badger Island American white pelican colony; 137 adult pelicans counted on or near island; pelicans nesting on both the upstream and mid-island sub-colonies; numerous pelican chicks observed

7/5/12 ›

Survey of recently formed Badger Island Caspian tern colony; no Caspian terns observed on-colony this week; the possible causes of colony failure include nest predation, flooding of part of the colony during high water last week, and decline in food availability as the salmonid out-migration winds down

7/5/12 ›

Fourteenth boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 187 cormorants, 127 pelicans, and 16 terns counted on Columbia River; a total of 101 pelicans, 19 cormorants, and 0 terns counted on Snake River

7/5/12 ›

Survey of former gull colonies on the mid-Columbia River near Richland, WA; on Island 20: about 3,300 nesting California gulls (most with chicks), 1,100 nesting ring-billed gulls (most with chicks), 2 black-crowned night-herons, and 1 nesting great blue heron; on Island 19: no nesting colonial waterbirds, 127 loafing ring-billed gulls and 22 loafing American white pelicans; on Island 18: no nesting colonial waterbirds, 109 loafing ring-billed gulls, 3 loafing American white pelicans, and 1 loafing great egret; on Nelson Island: no colonial piscivorous waterbirds observed

7/2/12 ›

Survey of North Potholes double-crested cormorant colony; 310 cormorants and 225 attended cormorant nests (some with fledglings) counted on colony; significant nest failure has occurred at this colony this breeding season; cause(s) of major nest failure at this largest cormorant colony in the Columbia Plateau region remain a mystery; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at North Potholes and none were detected

7/2 – 7/8/12 ›

High count of 298 Caspian terns on the Crescent Island colony this week, up from 223 last week; high count of 80 attended nests this week, down from 97 nests last week; the number of tern chicks counted on-colony decreased throughout the week, from 72 chicks (on 7/2) to 28 chicks (on 7/7); declining chick counts this week were likely due to chicks fledging and loafing near the water during periods of high temperatures; about 4,000 nesting gulls (mostly California gulls, most with chicks), 5 nesting great egrets (some with chicks), 4 nesting great blue herons (some with chicks), 2 nesting black-crowned night-herons (some with chicks), and 23 loafing double-crested cormorants also counted on island

7/2 – 7/8/12 ›

High count of 107 attended nests on the double-crested cormorant colony at Foundation Island, down from 130 attended nests last week; numerous cormorant fledglings observed on or near the colony; 1 nesting great blue heron (with chicks) also counted on island

7/2 – 7/8/12 ›

High count of 149 Caspian terns on the Goose Island-Potholes Reservoir colony this week, down from 165 terns last week; high count of 36 attended tern nests this week, down from 55 nests last week; the number of tern chicks counted on colony declined this week (33); declining counts of adults and chicks on colony were likely due to chicks fledgling and adults loafing near the water during periods of high temperatures; a minimum of 2,550 gulls (mostly nesting California and ring-billed gulls, some with fledglings), and 4 loafing American white pelicans also counted on the island

Weekly Update for 6/25 – 7/1/2012

6/28/12 ›

Survey of piscivorous waterbird colonies in Blalock Islands, mid-Columbia River; minimum count of about 985 nesting California gulls (some with chicks) on Anvil Island; 10 loafing Caspian terns, 2 loafing American white pelicans, and 53 loafing California gulls on sand bar between Anvil and Sand islands; minimum counts of 13 great blue heron nests (with chicks), 5 great egret nests (with chicks), 21 loafing Caspian terns, and 24 loafing California gulls on Sand Island; minimum count of 208 nesting ring-billed gulls on Straight Six Island (some with chicks); three previously active Caspian tern nests on sand bar between Anvil and Sand islands have failed (cause unknown)

6/28/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; minimum counts of 2,335 nesting California gulls (ca. 1,205 active nests, some with fledglings), 11 nesting ring-billed gulls (2 active nests, with at least 2 chicks), and 6 loafing double-crested cormorants on island

6/27/12 ›

Survey of Badger Island American white pelican colony; 135 adult pelicans counted on or near island; pelicans nesting on both the upstream and mid-island sub-colonies; numerous pelican chicks observed

6/27/12 ›

Survey of recently formed Badger Island Caspian tern colony; high count of Caspian terns this week was 3, down from 10 last week; high count of attended nests this week was 2, down from 8 last week; no Caspian tern chicks observed on-colony this week; the possible causes of tern chick mortality and nest failure include nest predation, flooding of part of the colony during high water last week, and decline in food availability as the salmonid out-migration winds down

6/27/12 ›

Thirteenth boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 155 cormorants, 63 pelicans, and 19 terns counted on Columbia River; a total of 96 pelicans, 21 cormorants, and 2 terns counted on Snake River

6/27/12 ›

Survey of North Potholes double-crested cormorant colony; 428 cormorants and 281 attended cormorant nests (some with chicks) counted on colony; significant nest failure has occurred at this colony this breeding season; the cormorant colony is now much less than half the number of nesting pairs that were recorded earlier in season; cause(s) of major nest failure at this largest cormorant colony in the Columbia Plateau region remain a mystery; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at North Potholes and none were detected

6/26/12 ›

38 Caspian tern chicks captured and banded at Goose Island tern colony in Potholes Reservoir

6/25/12 ›

89 Caspian tern chicks captured and banded at Crescent Island tern colony in mid-Columbia River

6/25 – 7/1/12 ›

High count of 223 Caspian terns on the Crescent Island colony this week, down from 292 last week; high count of 97 attended nests this week, down from 122 nests last week; the number of tern chicks counted on colony remained nearly stable this week, ranging from 79 to 84 chicks; the causes of high chick mortality in previous weeks may have been increased nest predation by California gulls and black-crowned night-herons, unseasonably wet and cold weather, and a decline in food availability as the salmonid out-migration winds down; ca. 4,500 nesting gulls (mostly California gulls, most with chicks), 3 nesting great egrets (some with chicks), 2 nesting great blue herons (with chicks), 1 nesting black-crowned night-heron, and 3 loafing double-crested cormorants also counted on island

6/25 – 7/1/12 ›

High count of 130 attended nests on the double-crested cormorant colony at Foundation Island, down from 203 attended nests last week; numerous cormorant fledglings observed on or near the colony; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at Foundation Island and none were detected; 2 nesting great blue herons (with chicks) also counted on island

6/25 – 7/1/12 ›

High count of 165 Caspian terns on the Goose Island-Potholes Reservoir colony this week, down from 207 terns last week; high count of 55 attended tern nests this week, similar to 56 nests last week; the number of tern chicks counted on colony remained relatively stable this week (47) after a dramatic decline during previous weeks; the cause(s) of this decline is uncertain, but may be related to a sharp decline in food availability coupled with unseasonably cool, wet weather; no evidence of increased predation on tern chicks was detected; a minimum of 4,125 gulls (mostly nesting California and ring-billed gulls, some with fledglings), and 6 loafing double-crested cormorants also counted on the island

Weekly Update for 6/18 – 6/24/2012

6/22/12 ›

Survey of Harper Island in Sprague Lake on the Columbia Plateau off the mid-Columbia River; ca. 1,020 nesting gulls (both California and ring-billed gulls with chicks), 144 nesting double-crested cormorants (125 attended nests, some with chicks), 11 loafing Caspian terns, and 2 loafing American white pelican were counted on island; previously active Caspian tern nests on Harper Island appear to have failed, cause unknown; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at Harper Island and none were detected

6/22/12 ›

Survey of piscivorous colonial waterbirds nesting on bridges at Lyons Ferry on the lower Snake River; 9 nesting great blue herons (6 active nests, some with chicks) and no cormorant nests found on trestle bridge

6/21/12 ›

Survey of piscivorous waterbird colonies in Blalock Islands, mid-Columbia River; minimum count of about 1,155 nesting California gulls (some with chicks) on Anvil Island; 7 loafing Caspian terns and 121 loafing California gulls on sand bar between Anvil and Sand islands; minimum counts of 6 nesting great blue herons (some nests with chicks), 8 nesting great egrets (some nests with chicks), 41 loafing Caspian terns, 22 loafing California gulls, and 2 loafing American white pelicans counted on Sand Island; minimum count of 331 nesting ring-billed gulls on Straight Six Island (some with chicks); three previously active Caspian tern nests on sand bar between Anvil and Sand islands have failed (cause unknown)

6/21/12 ›

Survey of Three Mile Canyon Island gull colony on mid-Columbia River; 44 loafing California gulls and 1 loafing American white pelican observed on island; all nesting attempts by California gulls on Three Mile Canyon Island failed in 2011 due to unknown causes and gulls have not attempted to nest on the island in 2012

6/21/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; minimum counts of 1,844 nesting California gulls (ca. 920 active nests, most with chicks), 10 nesting ring-billed gulls (2 active nests, with at least 1 chick), and 5 loafing double-crested cormorants counted on island

6/20/12 ›

Survey of Badger Island American white pelican colony; 98 adult pelicans counted on or near island; pelicans nesting on both the upstream and mid-island sub-colonies; numerous pelican chicks observed

6/20/12 ›

Survey of recently formed Badger Island Caspian tern colony; high count of Caspian terns this week was 10, down from 30 last week; high count of attended nests this week was 8, down from 18 last week; no Caspian tern chicks were observed on colony this week; the possible causes of tern chick mortality and nest failure include nest predation, flooding of part of the colony during high water last week, and decline in food availability as the salmonid out-migration winds down

6/20/12 ›

Twelfth boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 153 pelicans, 112 cormorants, and 77 terns counted on Columbia River; 48 pelicans, 33 cormorants, and 5 terns counted on Snake River during survey

6/20/12 ›

Survey of North Potholes double-crested cormorant colony; 469 cormorants and 301 attended cormorant nests (some with chicks) counted on colony; significant nest failure has occurred at this colony this breeding season; the cormorant colony is now less than half the number of nesting pairs that were recorded earlier in season; cause(s) of major nest failure at this largest cormorant colony in the Columbia Plateau region remain a mystery; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at North Potholes and none were detected

6/18 – 6/24/12 ›

High count of Caspian terns on the Crescent Island colony this week was 292, down from 431 last week; high count of attended nests was lower this week (122 nests) as compared to last week (177 nests); the number of tern chicks counted on colony remained stable this week, ranging from 88 to 93 chicks; the causes of chick mortality observed in previous weeks may have been associated with increased nest predation by California gulls and black-crowned night-herons, unseasonably wet and cold weather, and a decline in food availability as the salmonid out-migration winds down; ca. 4,000 nesting gulls (mostly California gulls, most with chicks), 6 nesting great egrets, 5 nesting great blue herons (some with chicks), 3 nesting black-crowned night-herons, and 4 loafing double-crested cormorant also counted on island

6/18 – 6/24/12 ›

High count of double-crested cormorant attended nests on the Foundation Island colony was lower this week (203 nests) compared to last week (229 nests); numerous cormorant fledglings observed on or near the colony; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at Foundation Island and none were detected; 12 nesting great blue herons (some with chicks) also counted on island

6/18 – 6/24/12 ›

High count of Caspian terns on the Goose Island-Potholes Reservoir colony was 207 this week, down from 505 last week; high count of attended nests was lower this week (56 nests) compared to last week (70 nests); terns initiated 7 new nests and laid eggs in previously failed areas on the colony this week; the number of tern chicks counted on colony remained relatively stable this week (53) after a dramatic decline during previous weeks; the cause of this decline is uncertain, but may be related to a sharp decline in food availability coupled with unseasonably cool, wet weather; no evidence of increased predation on tern chicks has been detected so far; a minimum of 4,500 gulls (mostly nesting California and ring-billed gulls, some with chicks), 6 loafing double-crested cormorants, 15 Canada geese (some with chicks) also counted on the island

Weekly Update for 6/11 – 6/17/2012

6/16/12 ›

Survey of piscivorous waterbird colonies in the Blalock Islands, mid-Columbia River; minimum count of about 1,080 nesting California gulls (200 active nests, most with chicks) on Anvil Island; 9 loafing Caspian terns and 31 loafing American white pelicans on sand bar between Anvil and Sand islands; minimum counts of 8 nesting great blue herons (some nests with chicks), 10 nesting great egrets (some nests with chicks), 5 loafing Caspian terns counted on Sand Island; minimum count of 217 nesting ring-billed gulls on Straight Six Island; three previously active Caspian tern nests on sand bar between Anvil and Sand islands have failed (cause unknown)

6/16/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; about 2,040 nesting California gulls (ca. 1,215 active nests, most with chicks), 10 nesting ring-billed gulls (2 active nests, most with chicks), and 3 loafing double-crested cormorants counted on island

6/15/12 ›

Survey of Okanogan double-crested cormorant colony; 27 adult double-crested cormorants and 26 attended cormorant nests counted (some with chicks); nearby were 17 adult great blue herons (19 active nests, some with chicks)

6/15/12 ›

Survey of Banks Lake on the Columbia Plateau off the mid-Columbia River; about 1,000 nesting California gulls (some with chicks) and 31 Caspian terns (1 active nest) were counted on Twining Island; about 1,300 nesting ring-billed gulls (some with chicks) and 9 nesting great blue herons (some with chicks) were counted on Goose Island; ca. 100 ring-billed gulls observed nesting (some with chicks) on a small unnamed island in the southwest section of Banks Lake

6/15/12 ›

Survey of Badger Island American white pelican colony; 209 adult pelicans counted on or near island; pelicans nesting on both the upstream and mid-island sub-colonies; numerous pelican chicks observed

6/15/12 ›

A small, moveable floating blind was used to approach a recently-formed Caspian tern colony on Badger Island without flushing or disturbing nesting American white pelicans; high count of Caspian terns on the Badger Island colony this week was 30, down from 84 last week; high count of attended nests this week was 18, down from 54 last week; no Caspian tern chicks were observed on colony this week; the causes of chick mortality and nest failure may be associated with nest predation, possible flooding of some of the colony during high water this week, and perhaps a decline in food availability as the salmonid out-migration winds down

6/15/12 ›

Eleventh boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 164 pelicans, 87 cormorants, and 85 terns counted on Columbia River; 27 pelicans, 23 cormorants, and 2 terns counted on Snake River during survey

6/13/12 ›

Survey of North Potholes double-crested cormorant colony; 538 cormorants and 375 attended cormorant nests (some with chicks) counted on colony; significant nest failure has occurred at this colony this breeding season; the cormorant colony is now less than half the number of nesting pairs that were recorded earlier in season; cause(s) of major nest failure at this largest cormorant colony in the Columbia Plateau region remain a mystery; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at North Potholes and none were detected

6/11 – 6/17/12 ›

High count of Caspian terns on the Crescent Island colony this week was 431, up from 381 last week; high count of attended nests was lower this week (177) as compared to last week (193); the number of tern chicks counted on colony remained stable this week, ranging from 84 to 94 chicks; high count of tern chicks on colony was dramatically lower this week (94) compared to last week (180); the causes of chick mortality may be associated with an increase in nest predation by California gulls and black-crowned night-herons, the unseasonably wet and cold weather that occurred last week, and perhaps a decline in food availability as the salmonid out-migration winds down; ca. 4,200 nesting gulls (mostly California gulls, some with chicks), 7 nesting great egrets, 4 nesting great blue herons (some with chicks), 2 nesting black-crowned night-herons, and one loafing double-crested cormorant also counted on island

6/11 – 6/17/12 ›

High count of double-crested cormorant attended nests on the Foundation Island was lower this week (229 nests) compared to last week (247 nests); numerous cormorant fledglings observed on or near the colony; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at Foundation Island and none were detected; 9 nesting great blue herons (some with chicks) also counted on island

6/11 – 6/17/12 ›

High count of Caspian terns on the Goose Island-Potholes Reservoir colony was 505 this week, up from 371 last week; high count of attended nests was much lower this week (70) as compared to last week (313); the number of tern chicks counted on colony remained relatively stable this week (62) after a dramatic decline last week; the cause of this decline is uncertain, but may be related to a sharp decline in food availability coupled with unseasonably cool, wet weather; no evidence of increased predation on tern chicks has been detected so far; a minimum of 4,000 gulls (mostly nesting California and ring-billed gulls, some with chicks), 6 loafing double-crested cormorants, 15 Canada geese (some with chicks) also counted on the island

6/11 – 6/17/12 ›

114 steelhead PIT-tagged at Rock Island Dam on mid-Columbia River this week, down from 304 steelhead PIT-tagged last week; conclusion of PIT-tagging efforts on steelhead smolts at Rock Island Dam on the upper Columbia River this season; 6,730 steelhead PIT-tagged and scored for condition to investigate factors affecting avian predation on the threatened Upper Columbia steelhead population

Weekly Update for 6/4 – 6/10/2012

6/8/12 ›

First double-crested cormorant fledglings observed at Foundation Island cormorant colony

6/7/12 ›

First Caspian tern chicks (3) observed on Badger Island tern colony

6/7/12 ›

Survey of Badger Island American white pelican colony; 214 pelicans counted on or near island; pelicans nesting on both the upstream and mid-island sub-colonies; first American white pelican chicks (2) observed on colony

6/7/12 ›

A small, moveable floating blind was used to approach a recently-formed Caspian tern colony on Badger Island without flushing or disturbing nesting American white pelicans; 84 Caspian terns were counted in a sandy upland area at the upstream end of Badger Island; 54 terns were attending nests, some with eggs and chicks

6/7/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; ca. 2,380 nesting California gulls (ca. 1,440 active nests, most with chicks), 124 nesting ring-billed gulls (52 active nests, most with chicks), two loafing double-crested cormorants, and one loafing American white pelican counted on island

6/7/12 ›

Survey of piscivorous waterbird colonies in the Blalock Islands, mid-Columbia River; minimum count of ca. 1,900 nesting California gulls (240 active nests, most with chicks) on Anvil Island; 7 nesting Caspian terns (3 active nests, some with eggs), 26 loafing Caspian terns, and 41 loafing California gulls on sand bar between Anvil and Sand islands; minimum count of 6 nesting great blue herons (some nests with chicks), 4 nesting great egrets, 17 loafing American white pelicans, 6 loafing Caspian terns, and 2 loafing Forster’s terns counted on Sand Island; minimum count of 253 nesting ring-billed gulls, 2 loafing California gulls, and 2 loafing American white pelicans on Straight Six Island; 45 loafing California gulls and one loafing double-crested cormorant on sand bar west of Anvil Island; one loafing American white pelican on Big Blalock Island; 2 loafing American white pelicans on Rock Island

6/7/12 ›

Tenth boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 93 terns, 85 pelicans, and 42 cormorants counted on Columbia River; 149 pelicans, 21 cormorants, and 7 terns counted on Snake River during survey

6/6/12 ›

Survey of North Potholes double-crested cormorant colony; 546 cormorants and 418 attended cormorant nests (some with chicks) counted on colony; significant nest failure has occurred at this colony this breeding season; the cormorant colony is now less than half the number of nesting pairs that were recorded earlier in season; cause(s) of major nest failure at this largest cormorant colony in the Columbia Plateau region remain a mystery; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at North Potholes and none were detected; remains of a fledgling great horned owl found near the colony

6/4 – 6/10/12 ›

High count of Caspian terns on the Crescent Island colony this week was 381, down from 532 last week; high count of attended nests was much lower this week (193) compared to last week (377); the number of tern chicks counted on colony declined dramatically this week, from 180 chicks at the beginning of the week to 106 chicks at the end of the week; the causes of chick mortality may be associated with an increase in nest predation by California gulls and black-crowned night-herons, the unseasonably wet and cold weather that occurred this week, and perhaps a decline in food availability as the salmonid out-migration winds down; ca. 4,300 nesting gulls (mostly California gulls), 9 nesting black-crowned night-herons, 5 nesting great egrets, 4 nesting great blue herons, 8 loafing American white pelicans, and one loafing double-crested cormorant also counted on island

6/4 – 6/10/12 ›

High count of double-crested cormorants on the Foundation Island colony this week was 213, down from 319 last week; high count of attended nests was lower this week (247 nests) as compared to last week (263 nests); telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at Foundation Island and none were detected; 9 nesting great blue herons (some with chicks) and 2 loafing black-crowned night-herons also counted on island

6/4 – 6/10/12 ›

High count of Caspian terns on the Goose Island-Potholes Reservoir colony was 371 this week, down from 514 last week; high count of attended nests was much lower this week (313) as compared to last week (434); as was the case for the Crescent Island tern colony, the number of tern chicks counted on colony declined dramatically this past week from 128 to 62 chicks; the cause of this decline is uncertain, but may be related to a sharp decline in food availability coupled with unseasonably cool wet weather; no evidence of increased predation on tern chicks has been detected so far; a minimum of 4,000 gulls (mostly nesting California and ring-billed gulls, some with chicks), 6 loafing double-crested cormorants, and one mallard also counted on the island

6/4 – 6/10/12 ›

304 steelhead PIT-tagged at Rock Island Dam on mid-Columbia River this week, down from 396 steelhead PIT-tagged last week; so far this season, 6,616 steelhead smolts have been PIT-tagged, 5,019 hatchery-reared and 1,597 wild smolts; juvenile steelhead are being PIT-tagged to investigate avian predation on the threatened Upper Columbia steelhead population

Weekly Update for 5/28 – 6/3/2012

6/1/12 ›

Survey of North Potholes double-crested cormorant colony; 595 cormorants and 432 attended cormorant nests (some with chicks) counted on colony; significant nest failure has occurred at this colony this breeding season; the cormorant colony is now less than half the numbers of nesting pairs that were recorded earlier in season; cause(s) of major nest failure at this largest cormorant colony in the Columbia Plateau region remain a mystery; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at North Potholes and none were detected

6/1/12 ›

Ninth boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 127 terns, 65 pelicans, and 43 cormorants counted on Columbia River; 84 pelicans, 27 cormorants, and 0 terns counted on Snake River during survey

6/1/12 ›

Survey of Badger Island American white pelican colony; 149 pelicans counted on or near island; pelicans nesting on both the upstream and mid-island sub-colonies

6/1/12 ›

A small, moveable floating blind was used to approach a recently-formed Caspian tern colony on Badger Island without flushing or disturbing nesting American white pelicans; 109 Caspian terns were counted in a sandy upland area at the upstream end of Badger Island; 60 terns were attending nests, some with eggs

6/1/12 ›

Survey of former gull colonies on the mid-Columbia River near Richland, WA; on Island 20: ca. 4,900 nesting gulls (both California and ring-billed gulls, most attending nests with chicks), 5 nesting black-crowned night-herons, 2 nesting great blue herons, 8 loafing American white pelicans, 3 loafing double-crested cormorants, and one loafing great egret; on Island 18: 86 ring-billed gulls (nesting status unknown), 3 loafing double-crested cormorants, 3 loafing Forster’s terns, and one loafing great egret; on Island 19: 98 ring-billed gulls (nesting status unknown) and one loafing great egret; on Nelson Island: one loafing great egret; these 4 islands will be closely monitored in the coming weeks to determine where gulls attempt to nest

5/31/12 ›

Survey of Harper Island in Sprague Lake on the Columbia Plateau off the mid-Columbia River; ca. 1,110 nesting gulls (both California and ring-billed gulls with chicks), 136 nesting double-crested cormorants (115 attended nests, some with chicks), 65 nesting Caspian (30 attended nests), 12 nesting Canada geese (with chicks), 5 loafing western grebes, one loafing American white pelican, one loafing black-crowned night-heron, and 10 American coots were counted on the island

5/30/12 ›

David Trachtenbarg (USACE) and 10 representatives from federal, state, and county agencies visited Goose Island in Potholes Reservoir

5/30/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; ca. 1,950 nesting California gulls, 13 nesting ring-billed gulls, and one loafing double-crested cormorant counted on island

5/30/12 ›

Survey of piscivorous waterbird colonies in the Blalock Islands, mid-Columbia River; minimum count of ca. 2,000 nesting California gulls on Anvil Island; 19 Caspian terns (one active nest with one egg) and 2 loafing American white pelicans counted on sand bar between Anvil and Sand islands; 16 nesting great blue herons (some nests with chicks), 11 nesting great egrets, 25 loafing Caspian terns, 16 loafing American white pelicans, 3 loafing California gulls, and one loafing black-crowned night-heron counted on Sand Island; minimum count of 700 nesting ring-billed gulls on Straight Six Island; 150 loafing California gulls and 8 loafing Caspian terns on sand bar west of Anvil Island

5/29 – 6/2/12 ›

High count of double-crested cormorants on the Foundation Island colony this week was 319, down from 430 last week; high count of attended nests was lower this week (263) as compared to last week’s count (310); telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at Foundation Island and none were detected; 9 nesting great blue herons (some with chicks), 12 loafing American white pelicans, 4 loafing Caspian terns, 3 loafing ring-billed gulls, and one loafing black-crowned night-heron also counted on island

5/29 – 6/2/12 ›

High count of Caspian terns on the Goose Island-Potholes Reservoir colony was 514 this week, down from 594 last week; high count of attended nests was lower this week (434) as compared to last week (463); a minimum of 4,500 gulls (mostly nesting California and ring-billed gulls, some with chicks) and 6 loafing double-crested cormorants also counted on the island

5/28 – 6/3/12 ›

Two new gull carcasses found on west end of Goose Island-Potholes Reservoir this week; cause of death unknown

5/28 – 6/3/12 ›

High count of Caspian terns on the Crescent Island colony this week was 532, down from 581 last week; high count of attended nests was lower this week (377) as compared to last week (422); ca. 4,250 nesting gulls (mostly California gulls), 8 nesting black-crowned night-herons, 4 nesting great blue herons, 3 nesting great egrets, 4 loafing double-crested cormorants, and 2 loafing American white pelicans also counted on island

5/28 – 6/3/12 ›

396 steelhead PIT-tagged at Rock Island Dam on mid-Columbia River this week, down from 812 steelhead PIT-tagged last week; so far this season, 6,312 steelhead smolts have been PIT-tagged, 4,774 hatchery-reared and 1,538 wild; juvenile steelhead are being PIT-tagged to investigate avian predation on the threatened Upper Columbia steelhead population

Weekly Update for 5/21 – 5/27/2012

5/24/12 ›

Survey of North Potholes double-crested cormorant colony; 700 cormorants and 595 attended cormorant nests (some with chicks) counted on colony; significant nest failure has occurred at this colony over the past two weeks; cause(s) of nest failure unknown; telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at North Potholes and none were detected

5/25/12 ›

Survey of Banks Lake on the Columbia Plateau off the mid-Columbia River; ca. 800 nesting California gulls, 14 nesting Caspian terns (6-8 active nests), and 6 loafing Canada geese were counted on Twining Island; ca. 1,000 nesting ring-billed gulls and 10 nesting great blue herons were counted on Goose Island

5/25/12 ›

Survey of Okanogan double-crested cormorant colony; 40 adult double-crested cormorants and 32 attended cormorant nests counted (some with chicks); nesting nearby were 22 great blue herons (20 active nests, some with chicks)

5/25/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; ca. 2,170 nesting California gulls and 8 nesting ring-billed gulls counted on island

5/25/12 ›

Survey of Three Mile Canyon Island gull colony on mid-Columbia River; 18 loafing California gulls and 2 loafing ring-billed gulls observed on island; all nesting attempts by California gulls on Three Mile Canyon Island failed in 2011 due to unknown causes and they have not attempted to renest on the island in 2012

5/25/12 ›

Survey of piscivorous waterbird colonies in the Blalock Islands, mid-Columbia River; minimum counts of ca. 2,500 nesting California gulls on Anvil Island (a deer also observed on island caused the gull colony to flush several times); 31 loafing Caspian terns and 4 loafing American white pelicans counted on sand bar between Anvil and Sand islands; 23 nesting great blue herons, 12 nesting great egrets, 5 loafing California gulls, 4 loafing Caspian terns, and 3 loafing American white pelicans counted on Sand Island; minimum count of 720 nesting ring-billed gulls on Straight Six Island

5/24/12 ›

Eighth boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 144 terns, 62 cormorants, and 18 pelicans counted on Columbia River; 174 pelicans, 64 cormorants, and 5 terns counted on Snake River during survey

5/24/12 ›

Survey of Badger Island American white pelican colony; 110 pelicans counted on or near island; pelicans nesting on both the upstream and mid-island sub-colonies

5/24/12 ›

A small, moveable floating blind was used to approach an incipient Caspian tern colony on Badger Island on Thursday (5/24) without flushing or disturbing nesting American white pelicans; 104 Caspian terns were counted from the blind in an upland area at the upstream end of Badger Island; 51 terns were attending nests, some with eggs

5/22 – 5/26/12 ›

High count of double-crested cormorants on the Foundation Island colony this week was 430 on Tuesday (5/22), up from 419 last week; high count of attended nests was similar this week (310) as compared to last week’s count (314); telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at Foundation Island and none were detected; 18 nesting great blue herons (some with chicks), 10 loafing Caspian terns, 6 loafing American white pelicans, and one loafing black-crowned night-heron also counted on island

5/21 – 5/27/12 ›

High count of Caspian terns on the Goose Island-Potholes Reservoir colony was 594 this week, down from 706 last week; high count of attended nests was higher this week (463) as compared to last week (401); a minimum of 4,000 gulls (mostly nesting California and ring-billed gulls, some with chicks), 2 loafing Canada geese, and 2 mallards also counted on the island

5/21 – 5/27/12 ›

No new gull carcasses found and no evidence of avian or mammalian predation on gulls at Goose Island, Potholes Reservoir this week

5/21 – 5/27/12 ›

High count of Caspian terns on the Crescent Island colony this week was 581 on Tuesday (5/22), down from 658 last week; high count of attended nests was higher this week (422) as compared to last week (385); ca. 4,100 nesting gulls (mostly California gulls), 2 nesting great egrets, 2 nesting great blue herons, 9 loafing black-crowned night-herons, and one loafing American white pelican also counted on island

5/21 – 5/27/12 ›

812 steelhead PIT-tagged at Rock Island Dam on mid-Columbia River this week, down from 1,563 steelhead PIT-tagged last week; juvenile steelhead are being PIT-tagged to investigate avian predation on the threatened Upper Columbia steelhead population

Weekly Update for 5/14 – 5/20/2012

5/19/12 ›

Seventh boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 191 terns, 41 cormorants, and 24 pelicans counted on Columbia River; 86 pelicans, 74 cormorants, and 4 terns counted on Snake River during survey

5/19/12 ›

Survey of Badger Island American white pelican colony; 160 pelicans counted on or near island; pelicans nesting on both the upstream and mid-island sub-colonies

5/18 – 5/19/12 ›

A small, moveable floating blind was used to approach an incipient Caspian tern colony on Badger Island on Friday (5/18) without flushing or disturbing nesting American white pelicans; on Saturday (5/19), 75 Caspian terns were counted from the blind in an upland area at the upstream end of Badger Island; 36 terns were attending nests and a minimum of 5 tern eggs were counted in these nests; ca. 180 Caspian terns were counted on the Badger Island Caspian tern colony from an aerial photo taken of the colony on Friday (5/18)

5/18/12 ›

Aerial photo census to estimate numbers of piscivorous colonial waterbirds (i.e., Caspian terns, gull spp., American white pelicans) at colonies on Miller Rocks, Crescent Island, and Badger Island in the mid-Columbia River, and Goose Island in Potholes Reservoir; counts of aerial photos will allow us to more accurately estimate the number of nesting piscivorous waterbirds at these colonies

5/17/12 ›

Survey of North Potholes double-crested cormorant colony; 862 cormorants and 758 attended cormorant nests (some with chicks) counted on colony; significant nest failure (ca. 20%) occurred at the colony this week as compared to the previous week; cause(s) of nest failure unknown; also nesting nearby were 263 great egrets (216 active nests), 88 great blue herons (81 active nests), and 40 black-crowned night-herons (33 active nests); telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at North Potholes and none were detected

5/15/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; ca. 2,033 nesting California gulls, 2 nesting ring-billed gulls, and 12 loafing double-crested cormorants counted on island

5/15/12 ›

Survey of piscivorous waterbird colonies in the Blalock Islands, mid-Columbia River; minimum counts of ca. 3,200 nesting California gulls and 2 loafing double-crested cormorants on Anvil Island; 81 Caspian terns, 2 of which were sitting in nest scrapes, counted on sand bar between Anvil and Sand islands; 21 nesting great blue herons, 12 nesting great egrets, 23 loafing Caspian terns, 10 loafing California gulls, and 8 loafing American white pelicans counted on Sand Island; minimum count of 700 nesting ring-billed gulls on Straight Six Island; 2 loafing American white pelicans counted on Rock Island (site of former Caspian tern colony); no birds observed on Little Blalock Island or Big Blalock Island

5/14 – 5/18/12 ›

High count of double-crested cormorants on the Foundation Island colony this week was 419 on Thursday (5/17), down from 525 last week; high count of attended nests was also lower this week (314) as compared to last week (347); telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at Foundation Island and none were detected; 13 nesting great blue herons, 51 loafing Caspian terns, 17 loafing American white pelicans, 16 loafing ring-billed gulls, 2 loafing great egrets, 5 loafing California gulls, and one loafing black-crowned night-heron also counted on island

5/14 – 5/20/12 ›

High count of Caspian terns on the Goose Island-Potholes Reservoir colony was 706 this week, up from 593 last week; high count of attended nests was also higher this week (401) as compared to last week (323); a minimum of 4,000 gulls (mostly nesting California and ring-billed gulls, some with chicks), 4 loafing Canada geese, and 2 mallards also counted on the island

5/14 – 5/20/12 ›

No new gull carcasses found and no evidence of avian predation on Goose Island, Potholes Reservoir this week; evidence of mink predation on gulls was found on Goose Island in previous weeks; there are no plans to attempt to remove the mink from the island at this time

5/14 – 5/20/12 ›

High count of Caspian terns on the Crescent Island colony this week was 658 on Thursday (5/17), down from 707 last week; high count of attended nests was higher this week (385) as compared to last week (376); ca. 3,000 nesting California gulls, 51 nesting ring-billed gulls, 10 nesting great egrets, 3 nesting great blue herons, 10 loafing black-crowned night-herons, and one loafing double-crested cormorant also counted on island

5/14 – 5/20/12 ›

1,563 steelhead PIT-tagged at Rock Island Dam on mid-Columbia River to investigate avian predation on juvenile steelhead from the threatened Upper Columbia population

Weekly Update for 5/7 – 5/13/2012

5/13/12 ›

54 adult Caspian terns captured at the Goose Island-Potholes Reservoir colony and banded with field-readable alphanumeric leg bands; thanks to David Trachtenbarg (USACE) for his assistance with banding

5/13/12 ›

100 PIT tags sown for a study of smolt PIT tag detection efficiency on the Caspian tern colony at Goose Island-Potholes Reservoir

5/12/12 ›

61 adult Caspian terns captured at the Crescent Island colony and banded with field-readable alphanumeric leg bands; thanks to David Trachtenbarg (USACE) for his assistance with banding

5/12/12 ›

50 PIT tags sown for a study of smolt PIT tag detection efficiency on the Caspian tern colony at Crescent Island

5/11/12 ›

David Trachtenbarg and Cindy Boen with USACE-Walla Walla District and Lamont Glass with the USFWS-Mid-Columbia NWR visited the bird colonies at Crescent Island, Badger Island, and Foundation Island

5/11/12 ›

First Caspian tern chick observed on Crescent Island tern colony; thanks to Lamont Glass for spotting the first chick of the year

5/11/12 ›

63 Caspian terns counted in an upland area at the upstream end of Badger Island, 30 of which were sitting in nest scrapes; Badger Island will be closely monitored in the coming weeks to determine if Caspian terns lay eggs at the site

5/9/12 ›

Survey of North Potholes double-crested cormorant colony; 1,093 cormorants and 924 attended cormorant nests (some with chicks) counted on colony

5/9/12 ›

Fish deposition study completed on the California gull colony at Crescent Island; 100 PIT-tagged fish fed to gulls at the colony to determine the rate at which consumed PIT-tagged fish are deposited on-colony

5/9 – 5/10/12 ›

High count of double-crested cormorants on the Foundation Island colony was 525 on Thursday (5/10), down from 983 last week; high count of attended nests was also lower this week (347) as compared to last week (390); telemetry surveys looking for radio-tagged cormorants from East Sand Island were conducted at Foundation Island and none were detected; 6 nesting great blue herons, 4 loafing American white pelicans, and one loafing black-crowned night-heron also counted on island

5/8/12 ›

First Caspian tern chick observed on Goose Island-Potholes Reservoir colony

5/8/12 ›

Fish deposition study completed on the Miller Rocks California gull colony; 100 PIT-tagged fish fed to gulls at the colony to determine the rate at which consumed PIT-tagged fish are deposited on-colony

5/8/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; ca. 1,596 gulls (mostly California gulls) counted on island, most attending nests; one loafing American white pelican also counted on island

5/8/12 ›

Survey of piscivorous waterbird colonies in the Blalock Islands, mid-Columbia River; minimum counts of 2,062 nesting California gulls, 56 loafing Caspian terns, 15 loafing ring-billed gulls, and 11 loafing American white pelicans on Anvil Island; 23 nesting great blue herons (18 active nests), 10 nesting great egrets (10 active nests), 29 loafing Caspian terns, 29 loafing ring-billed gulls, and 12 loafing American white pelicans counted on Sand Island; minimum count of 331 nesting ring-billed gulls and 16 loafing Caspian terns on Straight Six Island; 5 loafing American white pelicans counted on Big Blalock Island; one loafing California gull counted on Rock Island (site of former Caspian tern colony); no birds observed Little Blalock Island

5/7/12 ›

Sixth boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 255 terns, 58 cormorants, and 15 pelicans counted on Columbia River; 122 cormorants and 81 pelicans counted on Snake River during survey; a larger number of loafing Caspian terns observed on the Columbia River at the mouth of the Walla Walla River this week compared to previous weeks

5/7/12 ›

Survey of Badger Island American white pelican colony; 187 pelicans counted on or near island, up from the count the previous week (163); pelicans nesting on both the upstream and mid-island sub-colonies

5/7 – 5/13/12 ›

High count of Caspian terns on the Goose Island-Potholes Reservoir colony was 593 on Tuesday (5/8), up from 578 last week; high count of attended nests was also higher this week (323) as compared to last week (263); a minimum of 5,000 gulls (mostly nesting California and ring-billed gulls, some with chicks), 8 loafing Canada geese, and 2 mallards also counted on the island

5/7 – 5/13/12 ›

No new gull carcasses found and no evidence of avian predation on Goose Island, Potholes Reservoir this past week; evidence of mink predation was found on Goose Island in previous weeks; there are no plans to attempt to remove the mink from the island at this time

5/7 – 5/13/12 ›

High count of Caspian terns on the Crescent Island colony was 707 on Friday (5/11), up from 640 last week; high count of attended nests was also higher this week (376) as compared to last week (350); 4,850 nesting California gulls, 4 nesting great blue herons, 3 nesting great egrets, 3 loafing ring-billed gulls, and one loafing black-crowned night-heron also counted on island

5/7 – 5/13/12 ›

1,583 steelhead PIT-tagged at Rock Island Dam on mid-Columbia River to investigate avian predation on juvenile steelhead from the threatened Upper Columbia population

Weekly Update for 4/30 – 5/6/2012

5/4/12 ›

First visit to colonial waterbird nesting islands in Banks Lake; 1,500 nesting gulls (mostly California gulls), 27 nesting Caspian terns (3-4 active nests), and 10 Canada geese on Twining Island; 1,200 nesting gulls, 14 nesting great blue herons (12 active nests), and 6 Canada geese on Goose Island

5/3/12 ›

Survey of former gull colonies on the mid-Columbia River near Richland, WA; on Island 20: ca. 8,550 gulls (both California and ring-billed gulls, most attending nests), 6 black-crowned night-herons (4 attending nests), 2 great blue herons (both attending nests), and 4 loafing double-crested cormorants; on Island 18: 18 loafing California gulls (the large gull colony on Island 18 was abandoned in 2008 due to a combination of coyote and human disturbance); on Island 19: 33 loafing California gulls, 3 loafing double-crested cormorants, 3 foraging great egrets, and one loafing black-crowned night-heron; on Nelson Island: 30 California gulls (island will be closely monitored in the coming weeks to determine if gulls attempt to nest at the site)

5/3/12 ›

Fifth boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 38 terns, 62 cormorants, and 21 pelicans counted on Columbia River; 78 cormorants and 108 pelicans counted on Snake River during survey; a greater concentration of foraging cormorants, and pelicans observed on the Snake River near Ice Harbor Dam this week compared to previous weeks

5/3/12 ›

Survey of Badger Island American white pelican colony; 163 pelicans counted on or near island, down from the count the previous week (346); pelicans nesting on both the upstream and mid-island sub-colonies; also observed were 50 Caspian terns in upland area at the upstream end of badger island; Badger Island will be closely monitored in the coming weeks to determine if Caspian terns attempt to nest at the site

5/2/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; ca. 2,350 gulls (mostly California gulls) counted on island, most attending nests; 8 loafing double-crested cormorants also counted on island

5/2/12 ›

Survey of piscivorous waterbird colonies in the Blalock Islands, mid-Columbia River; minimum counts of 1,450 nesting gulls (mostly California gulls) and 74 loafing Caspian terns on Anvil Island; 16 great blue herons (14 active nests), 9 great egrets (8 active nests), one black-crowned night-heron attending a nest, 9 loafing California gulls, 6 loafing Caspian terns, and 5 loafing American white pelicans counted on Sand Island; minimum count of 300 nesting ring-billed gulls on Straight Six Island; 5 loafing double-crested cormorants counted on Big Blalock Island; no birds observed on Rock Island (site of former Caspian tern colony) or Little Blalock Island

5/2/12 ›

Survey of North Potholes double-crested cormorant colony; 1,175 cormorants and 992 attended cormorant nests (some with chicks) counted on colony; also nesting nearby were 189 great egrets (142 active nests), 84 great blue herons (83 active nests), and 33 black-crowned night-herons (27 active nests)

4/30 – 5/6/12 ›

High count of Caspian terns on the Goose Island-Potholes Reservoir colony was 578 on Thursday (5/3), up from 365 last week; high count of attended nests was also higher this week (263) as compared to last week (84);

4/30 – 5/6/12 ›

No new gull carcasses found and no evidence of avian predation on Goose Island, Potholes Reservoir this past week; evidence of mink predation was found on Goose Island the previous week; there are no plans to remove the mink from the island at this time

4/30 – 5/6/12 ›

High count of Caspian terns on the Crescent Island colony was 640 on Wednesday (5/2), up from 555 last week; high count of attended nests was also higher this week (350) as compared to last week (247)

4/30 – 5/6/12 ›

High count of double-crested cormorants on the Foundation Island colony was 683 on Tuesday (5/1), up from 564 last week; high count of attended nests was also higher this week (390) as compared to last week (354); telemetry surveys were conducted looking for radio-tagged cormorants from East Sand Island, none were detected

4/30 – 5/6/12 ›

1,473 steelhead PIT-tagged at Rock Island Dam on mid-Columbia River to investigate avian predation on juvenile steelhead from the threatened Upper Columbia population

Weekly Update for 4/23 – 4/29/2012

4/28/12 ›

First double-crested cormorant chicks (ca. 6 days post-hatch) observed on Foundation Island cormorant colony; the count of active cormorant nests on Foundation Island was 354, the highest so far this season

4/28/12 ›

Complete waterbird survey of Goose Island, Potholes Reservoir; more than 5,000 gulls nesting on island, east side of island dominated by nesting California gulls and west side of island dominated by nesting ring-billed gulls; more than 300 nesting Caspian terns counted, almost entirely on west side of island; also observed on island were 20 Canada geese (3 active nests) and 12 mallards

4/28/12 ›

5 fresh gull carcasses found on Goose Island, Potholes Reservoir; 3 of the fresh kills were pulled into a beaver lodge on the north end of island and had bite marks that were consistent with a mink; there are no plans to remove the mink from the island at this time; no evidence of avian predation at the Goose Island colony this past week

4/27/12 ›

Complete waterbird survey of Crescent Island, mid-Columbia River; 555 Caspian terns counted, 240 attending nests; ca. 4,350 California gulls counted with most attending nests; also observed on island were 3 black-crowned night-herons (2 active nests) and 5 loafing double-crested cormorants

4/27/12 ›

Complete waterbird survey of Foundation Island, mid-Columbia River; 506 double-crested cormorants counted, 340 attending nests; also observed on island were 8 great blue herons (6 active nests) and one loafing black-crowned night-heron

4/27/12 ›

First visit to Harper Island in Sprague Lake; 115 double-crested cormorants (at least 70 active nests) and ca. 2,500 gulls counted on island, some nesting; no Caspian terns observed on island (site of former Caspian tern colony)

4/25/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; ca. 3,000 gulls (mostly California gulls) counted on island, most attending nests; 3 loafing American white pelican also observed on island

4/25/12 ›

Survey of Three Mile Canyon Island gull colony on mid-Columbia River; no nesting by gulls or any other ground-nesting birds (e.g., Canada geese) observed on island; fresh raccoon tracks and scat observed on island the previous week; all nesting attempts by California gulls on Three Mile Canyon Island failed in 2011 due to unknown causes

4/25/12 ›

Survey of piscivorous waterbird colonies in the Blalock Islands, mid-Columbia River; water levels unusually high and none of the sand spits or shoreline beach areas were visible; minimum counts of 937 nesting gulls (mostly California gulls), 5 loafing American white pelicans, and 3 black-crowned night-herons (one active nest) on Anvil Island; 11 great blue herons (9 active nests), 7 great egrets (6 active nests), 5 loafing California gulls, 4 loafing American white pelicans, and two loafing double-crested cormorants counted on Sand Island; minimum count of 327 nesting ring-billed gulls on Straight Six Island; 10 loafing American white pelicans counted on Big Blalock Island; no birds observed on Rock Island (site of former Caspian tern colony) or Little Blalock Island

4/25/12 ›

Survey of North Potholes double-crested cormorant colony; 1,062 cormorants and 771 attended cormorant nests (some with chicks) counted on colony; also nesting nearby were 73 great egrets (46 active nests)

4/24/12 ›

Fourth boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia and Snake rivers; a total of 14 terns, 60 cormorants, and 7 pelicans counted on Columbia River and 102 cormorants and 91 pelicans counted on Snake River during survey

4/23/12 ›

Survey of Badger Island American white pelican colony; 346 pelicans counted on or near island; pelicans nesting on both the upstream and mid-island sub-colonies; 101 loafing California gulls also counted on island

4/23 – 4/29/12 ›

423 steelhead PIT-tagged at Rock Island Dam on Columbia River to investigate avian predation on juvenile steelhead from the threatened Upper Columbia population

Weekly Update for 4/16 – 4/22/2012

4/20/12 ›

Survey of Okanogan double-crested cormorant colony; 63 adult double-crested cormorants and 40 attended cormorant nests counted, cormorant chicks not observed; nesting nearby were 20 great blue herons (19 active nests)

4/19/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; ca. 2,000 gulls (mostly California gulls) counted on island; no nesting Caspian terns or double-crested cormorants observed; 13 loafing double-crested cormorants and one loafing American white pelican also observed on island

4/19/12 ›

Survey of piscivorous waterbird colonies in Blalock Islands, mid-Columbia River; ca. 1,750 nesting gulls (mostly California gulls), 83 Caspian terns, 4 loafing double-crested cormorants, and two loafing American white pelicans counted on Anvil Island; 5 nesting great blue herons, 4 nesting great egrets, 42 loafing Caspian terns, 4 loafing double-crested cormorants, and 3 loafing American white pelicans counted on Sand Island; 850 nesting gulls (mostly ring-billed gulls) counted on Straight Six Island; 5 loafing American white pelicans and 3 loafing double-crested cormorants counted on Big Blalock Island; 7 loafing American white pelicans and one loafing double-crested cormorant counted on Little Blalock Island; no birds observed on Rock Island (site of former Caspian tern colony)

4/19/12 ›

Survey of Three Mile Canyon Island gull colony on mid-Columbia River; no nesting by gulls or any other ground-nesting birds (e.g., Canada geese) observed on island; fresh raccoon tracks and scat observed on island; all nesting attempts by California gulls on the Three Mile Canyon Island gull colony failed in 2011 due to unknown causes

4/19/12 ›

Complete waterbird survey of Goose Island, Potholes Reservoir; more than 4,000 gulls nesting on island, east side of island dominated by nesting California gulls and west side of island dominated by nesting ring-billed gulls; more than 200 nesting Caspian terns counted, almost entirely on west side of island; also observed on island were Canada geese (12 active nests), mallards (5 active nests), 12 loafing dunlin, and 3 loafing double-crested cormorants

4/18/12 ›

Survey of North Potholes double-crested cormorant colony; 1,025 cormorants and 750 attended cormorant nests with chicks counted on colony; nesting nearby were 78 black-crowned night-herons (50 active nests), 43 great blue herons (36 active nests), and 29 great egrets (15 active nests)

4/17/12 ›

Third boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia River from mouth of Walla Walla River to Port of Benton and on Snake River from confluence with Columbia River to Ice Harbor Dam; terns, cormorants, and pelicans seen on their respective colonies and commuting up and down river (counts will be provided in a subsequent report)

4/17/12 ›

Survey of Badger Island American white pelican colony; 220 pelicans counted on or near island; 17 loafing Caspian terns and 27 loafing double-crested cormorants also counted on island

4/16 – 4/22/12 ›

43 steelhead PIT-tagged at Rock Island Dam on Columbia River to investigate avian predation on juvenile steelhead from the threatened Upper Columbia population

4/16 – 4/22/12 ›

Signs of multiple predators observed on or near Goose Island, Potholes Reservoir; 4 fresh gull carcasses found on island, believed to have been preyed upon by river otters; 2 fresh bird carcasses (waterfowl) found on small rock island immediately adjacent to Goose Island, most likely depredated by bald eagles or great horned owls

Weekly Update for 4/9 – 4/15/2012

4/14/12 ›

Commencement of steelhead smolt PIT-tagging at Rock Island Dam on mid-Columbia River to investigate avian predation on juvenile steelhead from the threatened Upper Columbia population

4/14/12 ›

First Caspian tern egg observed on Goose Island tern colony, Potholes Reservoir

4/12/12 ›

First Caspian tern egg observed on Crescent Island tern colony, mid-Columbia River

4/11/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; more than a thousand gulls (mostly California gulls) counted on island; no nesting Caspian terns or double-crested cormorants observed; one loafing double-crested cormorant observed on island

4/11/12 ›

Survey of piscivorous waterbird colonies in Blalock Islands, mid-Columbia River; ca. 2,300 gulls (mostly California gulls), 6 loafing American white pelicans, and 3 loafing Caspian terns counted on Anvil Island; 3 great blue herons (1 active nests), 26 loafing Caspian terns, and 6 loafing American white pelicans counted on Sand Island; 89 gulls (mostly ring-billed gulls) counted on Straight Six Island; 11 loafing double-crested cormorants and two loafing American white pelicans counted on Big Blalock Island; 5 loafing double-crested cormorants counted on Little Blalock Island; one loafing American white pelican counted on Rock Island (site of former Caspian tern colony); an immature eagle observed perched in tree on Sand Island may have caused decline in number of attended heron nests this week compared to last week; Caspian terns have not yet initiated nesting on any of the Blalock Islands this season

4/10/12 ›

Survey of North Potholes double-crested cormorant colony; 851 cormorants and 619 attended nests counted on colony; great egrets (10) seen loafing at the colony site for first time this season

4/9/12 ›

Survey of Badger Island American white pelican colony; 157 pelicans counted on or near island; 9 loafing Caspian terns and 6 loafing double-crested cormorants also counted on island

4/9/12 ›

Second boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia River from mouth of Walla Walla River to Port of Benton and on Snake River from confluence with Columbia River to Ice Harbor Dam; terns, cormorants, and pelicans seen on their respective colonies and commuting up and down river (counts will be provided in a subsequent report)

4/9 – 4/15/12 ›

Signs of multiple predators observed on or near Goose Island, Potholes Reservoir; one fresh gull carcass found on island; after further investigation we believe that the gull carcasses collected on the island thus far this season were either killed or scavenged by river otters; 9 bird carcasses (mostly waterfowl) and castings found on small rock island immediately adjacent to Goose Island, most likely from bald eagles and great horned owls

Weekly Update for 4/2 – 4/8/2012

4/6/12 ›

Survey of Miller Rocks gull colony on mid-Columbia River; more than a thousand gulls (mostly California gulls) counted on island; no nesting Caspian terns or double-crested cormorants observed; 12 loafing double-crested cormorants observed on islands

4/6/12 ›

Survey of piscivorous waterbird colonies in Blalock Islands, mid-Columbia River; 580 gulls (mostly California gulls) counted on Anvil Island; 14 great blue herons (4 active nests), 6 loafing American white pelicans, and 53 gulls counted on Sand Island; 146 ring-billed gulls counted on Straight Six Island; Rock Island (site of former Caspian tern colony), Little Blalock Island, and Big Blalock Island not occupied by nesting or roosting birds; an immature eagle and a Caspian tern seen flying near the Blalock Islands

4/6/12 ›

Survey of Three Mile Canyon Island gull colony on mid-Columbia River; no nesting gulls observed on island; all nesting attempts by California gulls on Three Mile Canyon Island failed in 2011 from unknown causes; fresh raccoon tracks and evidence of human presence were observed on the island prior to colony abandonment last year

4/5/12 ›

Survey of Badger Island American white pelican colony; 125 pelicans counted on or near island

4/4/12 ›

First boat-based survey of off-colony distribution of foraging Caspian terns, double-crested cormorants, and American white pelicans conducted on Columbia River from mouth of Walla Walla River to Port of Benton and on Snake River from confluence with Columbia River to Ice Harbor Dam; terns, cormorants, and pelicans seen on their respective colonies and commuting up and down river (counts will be provided in a subsequent report)

4/3/12 ›

Survey of North Potholes double-crested cormorant colony; 731 cormorants and 476 attended nests counted on colony; nesting nearby were 36 great blue herons (32 active nests), 45 black-crowned night herons (23 active nests), and one bald eagle (possibly with chicks); no nesting great egrets were present in the heron rookery

4/2 – 4/8/12 ›

Signs of multiple predators observed on or near Goose Island, Potholes Reservoir; seven fresh gull carcasses found on island, which appeared to have been killed or scavenged by mink or river otter; two great horned owls heard calling at nearby Mar Don Resort; five raptor castings containing bones and feathers found on a small rock island immediately adjacent to Goose Island; castings most likely from bald eagles and great horned owls

Update FOR 3/8 – 4/1/2012

3/31/12 ›

Completed preparations for monitoring gull colony on Miller Rocks in mid-Columbia River; PIT tags sown for smolt PIT tag detection efficiency study; hundreds of gulls observed on-colony and 19 double-crested cormorants observed roosting on island; one fresh gull carcass found on island, appeared to be killed or scavenged by an avian predator

3/31/12 ›

Completed preparations for monitoring Caspian tern colony on Blalock Islands in mid-Columbia River; PIT tags sown for smolt PIT tag detection efficiency study; Caspian terns not seen in area of former colony; one bald eagle observed loafing on Anvil Island; two fresh gull carcasses found on island, one appeared to be killed or scavenged by an avian predator

3/31/12 ›

First Caspian terns (11) observed on Goose Island tern colony, Potholes Reservoir

3/31/12 ›

PIT tags sown for smolt PIT tag detection efficiency study on the Goose Island tern colony, Potholes Reservoir

3/29/12 ›

PIT tags sown for smolt PIT tag detection efficiency studies on the Crescent Island tern and gull colonies and the Foundation Island cormorant colony

3/28/12 ›

First Caspian terns (3) observed on Crescent Island tern colony in mid-Columbia River

3/28/12 ›

Completed preparations for monitoring Caspian tern colony on Crescent Island in mid-Columbia River

3/28/12 ›

Completed construction of observation blind near Foundation Island double-crested cormorant colony; completed preparations for monitoring double-crested cormorant colony on Foundation Island in mid-Columbia River

3/27/12 ›

First double-crested cormorants recorded at Foundation Island colony in the mid-Columbia River by project staff in 2012; ~ 200 cormorants observed in trees

3/27/12 ›

First Caspian terns sighted on mid-Columbia River by project staff in 2012; several seen flying near Foundation Island

3/25/12 ›

Completed preparations for monitoring double-crested cormorant colony at North Potholes; PIT tags sown for smolt PIT tag detection efficiency study; hundreds of cormorants observed on colony, some incubating eggs

3/24/12 ›

PIT tags sown for smolt PIT tag detection efficiency study on Goose Island gull colonies, Potholes Reservoir

3/24/12 ›

Completed preparations for monitoring Caspian tern colony on Goose Island, Potholes Reservoir; large numbers of California and ring-billed gulls observed on island; no Caspian terns seen on-colony

3/22 – 3/31/12 ›

Signs of multiple predators observed on or near Goose Island, Potholes Reservoir; great horned owl heard calling at nearby Mar Don Resort; two fresh gull carcasses found on island, appeared to be killed or scavenged by mink or river otter

3/22/12 ›

First Caspian terns sighted at Potholes Reservoir by project staff in 2012; several seen flying near Goose Island

3/20/12 ›

Seasonal field crew began working in Columbia Plateau region

3/8/12 ›

First American white pelicans observed on Badger Island in mid-Columbia River by project staff in 2012; because of presence of pelicans on island, no PIT tags were spread on-colony for smolt PIT tag detection efficiency study

The weekly update of events at various piscivorous waterbird colonies in the Columbia River estuary.

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