Weekly Update for 8/13 – 8/19/2012
8/13 – 8/19/12 ›
This completes our weekly reporting of field research activities in the Columbia River estuary for 2012
8/13 – 8/19/12 ›
Adult and juvenile double-crested cormorants continue to abandon the colony area and loaf elsewhere on East Sand Island; bald eagle presence at the East Sand Island double-crested cormorant colony decreased, with no cormorant flushes observed this past week
8/13 – 8/19/12 ›
All dissuasion-related monitoring on the East Sand Island double-crested cormorant colony has been completed for 2012
8/13 – 8/19/12 ›
Eleven satellite-tagged double-crested cormorants that were captured in the dissuasion area of the East Sand Island cormorant colony are currently being tracked; all 11 individuals were detected this past week in the Columbia River estuary around East Sand Island or Rice Island; this is the last weekly update on satellite-tagged double-crested cormorants for the 2012 breeding season
8/13 – 8/19/12 ›
Tracking of VHF radio-tagged double-crested cormorants that were captured in the dissuasion area of the East Sand Island cormorant colony has been completed for 2012
8/13 – 8/19/12 ›
Counts of Brandt’s cormorants on the East Sand Island colony are no longer feasible due to chicks leaving the nesting areas and loafing in widely dispersed areas around the west end of the island
8/13 – 8/19/12 ›
High count this week of about 4,685 Caspian terns on the East Sand Island colony, down from the previous week's high count of about 6,490 terns; low count this week was about 2,347 terns, down from last week's low count of about 5,642 terns; about 250 nests with eggs, some with small chicks, remain on colony as there was a second wave of nesting at the colony after many terns failed in their first nesting attempt due to high rates of nest predation by gulls
8/13 – 8/19/12 ›
Signs of multiple predators observed on East Sand Island; bald eagles and peregrine falcons continue to cause Caspian terns to flush from the colony; fresh raccoon tracks were observed on the north beach
Weekly Update for 8/6 – 8/12/2012
8/7/12 ›
Survey of the Miller Sands Spit American white pelican colony; minimum counts of 15 adult American white pelicans and 2 chicks
8/7/12 ›
Dr. Chen Shuihua (Zhejiang Natural History Museum, China) visited East Sand Island
8/6 – 8/12/12 ›
Adult and juvenile double-crested cormorants have begun to abandon the colony area and loaf elsewhere on East Sand Island, however about 20 recently hatched cormorant chicks were observed on colony this week; bald eagle presence at the East Sand Island double-crested cormorant colony decreased, with no cormorant flushes observed this past week
8/6 – 8/12/12 ›
All dissuasion-related monitoring on the East Sand Island double-crested cormorant colony has been completed for 2012
8/6 – 8/12/12 ›
Eleven satellite-tagged double-crested cormorants that were captured in the dissuasion area of the East Sand Island cormorant colony are currently being tracked; all 11 individuals were detected this past week in the Columbia River estuary around East Sand Island or Rice Island
8/6 – 8/12/12 ›
Tracking of VHF radio-tagged double-crested cormorants that were captured in the dissuasion area of the East Sand Island cormorant colony has been completed for 2012
8/6 – 8/12/12 ›
Counts of Brandt’s cormorants on the East Sand Island colony are no longer feasible due to chicks leaving the nesting areas and loafing in widely dispersed areas around the west end of the island
8/6 – 8/12/12 ›
High count this week of about 6,490 Caspian terns on the East Sand Island colony, down from the previous week's high count of about 7,980 terns; low count this week was about 5,642 terns, down from last week's low count of about 6,865 terns; about 400-500 nests with eggs, some with small chicks, remain on colony as there was a second wave of nesting at the colony after many terns failed in their first nesting attempt due to high rates of nest predation by gulls; most chicks successfully raised in the first wave of nesting have since fledged and have left the colony; there has been a noticeable decline in both gull predation pressure on tern nests and gull kleptoparasitism rates on tern bill loads in recent weeks
8/6 – 8/12/12 ›
Signs of multiple predators observed on East Sand Island; bald eagles continue to cause small numbers of Caspian terns to flush from the colony; a great horned owl was documented depredating a ring-billed gull; fresh raccoon tracks were observed on the northeast beach
Weekly Update for 7/30 – 8/5/2012
8/5/12 ›
About 9,750 California brown pelicans were counted roosting on East Sand Island, down from about 10,570 counted on 7/22; a greater number of brown pelicans were observed roosting on the north beach compared to previous weeks; about 1,900 pelicans were also observed roosting on Jetty “A” near Cape Disappointment
7/30 – 8/5/12 ›
Adult and juvenile double-crested cormorants have begun to abandon the colony area and loaf elsewhere on East Sand Island; bald eagle presence at the East Sand Island double-crested cormorant colony decreased, with no cormorant flushes observed this week
7/30 – 8/5/12 ›
All dissuasion-related monitoring on the East Sand Island double-crested cormorant colony has been completed for 2012
7/30 – 8/5/12 ›
Eleven satellite-tagged double-crested cormorants that were captured in the dissuasion area of the East Sand Island cormorant colony are currently being tracked; all 11 individuals were detected this week in the Columbia River estuary around East Sand Island or Rice Island
7/30 – 8/5/12 ›
Tracking of VHF radio-tagged double-crested cormorants that were captured in the dissuasion area of the East Sand Island cormorant colony has been completed for 2012
7/30 – 8/5/12 ›
High count of Brandt’s cormorants on the East Sand Island colony this week was 2,129, up from last week’s high count (1,688); fledglings have mostly left the nesting areas and are loafing in widely dispersed areas around the west end of the island
7/30 – 8/5/12 ›
High count this week of about 7,980 Caspian terns on East Sand Island, down considerably from the previous week's high count of about 14,045 terns; low count this week was about 6,865 terns, similar to last week's low count of about 6,870 terns; about 1,000 nests with eggs, some with small chicks, remain on colony as there was a second wave of nesting at the colony after many terns failed in their first nesting attempt due to high rates of nest predation by gulls; most chicks successfully raised in the first wave of nesting have since fledged and have left the colony; there has been a noticeable decline in both gull predation pressure on tern nests and kleptoparasitism rates on tern bill loads in recent weeks
7/30 – 8/5/12 ›
Signs of multiple predators observed on East Sand Island; bald eagles and peregrine falcons continue to cause small numbers of Caspian terns to flush from the colony; a great horned owl was documented depredating a tern chick on Friday (8/3); fresh river otter and raccoon tracks were observed on the northeast beach
Weekly Update for 7/23 – 7/29/2012
7/29/12 ›
Survey of the Miller Sands Spit American white pelican colony; minimum counts of 168 adult American white pelicans and 44 chicks
7/26/12 ›
Paul Schmidt and Elisa Carlsen with the U.S. Army Corps of Engineers visited East Sand Island
7/24/12 ›
First Brandt’s cormorant fledgling observed at the East Sand Island cormorant colony
7/23 – 7/29/12 ›
Adult and juvenile double-crested cormorants have begun to abandon the colony area and loaf elsewhere on East Sand Island; bald eagle presence at the East Sand Island double-crested cormorant colony decreased, with no cormorant flushes observed this week
7/23 – 7/29/12 ›
All dissuasion-related monitoring on the East Sand Island double-crested cormorant colony has been completed for 2012; large numbers of roosting cormorants (more than 1,000 individuals) were regularly observed on the Astoria-Megler Bridge this week
7/23 – 7/29/12 ›
Eleven satellite-tagged double-crested cormorants that were captured in the dissuasion area of the East Sand Island cormorant colony are currently being tracked; all 11 individuals were detected this week in the Columbia River estuary around East Sand Island, the Astoria-Megler Bridge, Rice Island, or Miller Sands Spit
7/23 – 7/29/12 ›
Tracking of VHF radio-tagged double-crested cormorants has been completed for 2012; no surveys were conducted this week
7/23 – 7/29/12 ›
High count of Brandt’s cormorants this week on the East Sand Island colony was 1,688, down from last week’s high count (2,256); 810 active Brandt’s cormorant nests were counted this week, slightly down from last week’s count of 840 nests
7/23 – 7/29/12 ›
High count this week of about 14,045 Caspian terns on East Sand Island, up from the previous week's high count of about 12,015 terns; low count this week was about 6,870 terns, also up slightly from last week's low count of about 6,160; an appreciable number of younger chicks and eggs remain on the colony, as there was a second wave of nesting at the colony after many terns failed in their first nesting attempt due to high levels of nest predation by gulls; there has been a noticeable decline in gull pressure on both tern nests and bill loads in recent weeks
7/23 – 7/29/12 ›
Signs of multiple predators observed on East Sand Island; bald eagles were observed killing two juvenile double-crested cormorants; peregrine falcons were seen regularly at the east end of the island, with evidence of at least one depredated Caspian tern; a great horned owl was documented depredating tern chicks on multiple occasions; a northern harrier caused a large flush at the East Sand Island tern colony on 7/24; fresh river otter and raccoon tracks were observed on the north beach
Weekly Update for 7/16 – 7/22/2012
7/22/12 ›
About 10,570 California brown pelicans were counted roosting on East Sand Island, the highest count so far this season; brown pelicans were mostly roosting on the southeast beach, the main pile dike beach, on the rip-rap in the cormorant dissuasion area, and on the west jetty
7/20/11 ›
71 American white pelican chicks were captured and banded with field-readable alphanumeric leg bands at the Miller Sands Spit colony; 20 pelican chicks that were too small to band were also observed on colony; thanks to Tiffany Cross (NOAA Fisheries), Jeff Heitsch, and Skylar Lamberton for their assistance with white pelican chick banding
7/19/12 ›
118 double-crested cormorant chicks were captured and banded with field-readable alphanumeric leg bands at the East Sand Island cormorant colony; in total, 440 double-crested cormorant chicks were banded at the East Sand Island colony in 2012
7/18/12 ›
Jen Zamon and Tiffany Cross with NOAA Fisheries visited East Sand Island
7/16/12 ›
First double-crested cormorant fledgling observed at East Sand Island cormorant colony
7/16 – 7/22/12 ›
Late wave of renesting double-crested cormorants on East Sand Island had chicks that were about 2 weeks old by week’s end; bald eagle presence at the East Sand Island double-crested cormorant colony increased this week, although cormorants did not readily flush from the colony as a result
7/16 – 7/22/12 ›
All dissuasion-related monitoring on the East Sand Island double-crested cormorant colony has been completed for 2012; large aggregations of double-crested cormorants (more than 3,000 individuals) continue to roost in and adjacent to the dissuasion area throughout the day; large numbers of roosting cormorants (more than 1,000 individuals) were also regularly observed on the Astoria-Megler Bridge this week
7/16 – 7/22/12 ›
Of the 74 currently active VHF radio-tagged double-crested cormorants, 37 (50%) were detected on East Sand Island at least once this week; one additional radio-tagged cormorant was detected on the Astoria-Megler Bridge
7/16 – 7/22/12 ›
Eleven double-crested cormorants that were satellite-tagged on East Sand Island are still transmitting a signal; 10 were detected in the Columbia River estuary (defined for these purposes as the mouth of the Columbia River upriver to Puget Island)and one was detected in Willapa Bay this week
7/16 – 7/22/12 ›
High count of Brandt’s cormorants this week on the East Sand Island colony was 2,256, similar to last week’s high count (2,567); 840 active Brandt’s cormorant nests were counted this week, down from last week’s count of 933 nests
7/16 – 7/22/12 ›
High count this week of about 12,015 Caspian terns on East Sand Island, similar to the previous week's high count of about 12,725 terns; low count this week was about 6,160 terns, also similar to last week's low count of about 5,649; average count for the week (9,510) was the highest average count in close to 3 months and the second highest weekly average for the entire breeding season; tern chicks continued to fledge from the colony all week; an appreciable number of younger chicks and eggs remain on the colony, as there was a second wave of nesting at the colony after many terns failed in their first nesting attempt due to high levels of nest predation by gulls; there has been a noticeable decline in gull pressure on both tern nests and bill loads in recent weeks
7/16 – 7/22/12 ›
Signs of multiple predators observed on East Sand Island; an adult bald eagle was seen killing a loafing double-crested cormorant; peregrine falcons seen daily at the east end of the island, mostly over the ring-billed gull colony; great horned owl seen during the day in trees in the center of the island on 7/18-7/19; one juvenile tern seen depredated by an owl on 7/18; there was a large flush at the East Sand Island tern colony at last light on 7/22, presumably caused by an owl
Weekly Update for 7/9 – 7/15/2012
7/15/12 ›
First Caspian tern fledgling observed at East Sand Island tern colony
7/10/12 ›
Aerial survey of the Columbia River estuary, Chehalis River, Grays Harbor, and the Salish Sea; main objectives of the flight were to (1) scan for radio-tagged cormorants from East Sand Island, (2) detect and photograph new and existing Caspian tern and double-crested cormorant colonies, and (3) observe the American white pelican colony on Miller Sands Spit; see below for radio-tagged cormorant and American white pelican results; see Coastal Washington weekly update for status of Caspian tern breeding coloniesin the Salish Sea region
7/10/12 ›
Aerial survey of the Miller Sands Spit American white pelican colony; 427 adults, 79 large chicks, and at least 20 nests with small chicks or eggs were counted in aerial photos taken of the colony
7/9 – 7/15/12 ›
Several sections of the East Sand Island double-crested cormorant colony experienced a new wave of hatching this past week, with most of the newly hatched chicks being about 7 days old; the oldest chicks are at least 42 days old and continue to disperse from their nests to form large on-colony crèches; bald eagle disturbances at the East Sand Island double-crested cormorant has declined considerably over the past several weeks
7/9 – 7/15/12 ›
Dissuasion area on the East Sand Island double-crested cormorant colony was surveyed five days this week to confirm that no breeding cormorants were present; regular hazing events in the dissuasion area were not conductedthis week; large aggregations of double-crested cormorants (more than 3,000 individuals) observed roosting in and adjacent to the dissuasion area; large numbers of roosting cormorants (more than 1,500 individuals) were also regularly observed on the Astoria-Megler Bridge this week, suggesting that failed breeders from East Sand Island are roosting on the bridge
7/9 – 7/15/12 ›
Of the 74 currently active VHF radio-tagged double-crested cormorants, 40 (54%) were detected on East Sand Island at least once this week; one additional radio-tagged cormorant was detected on the Astoria-Megler Bridge; no radio-tagged double-crested cormorants from East Sand Island were detected outside the Columbia River estuary during an aerial survey flown on 7/10 (see above)
7/9 – 7/15/12 ›
Eleven of 11 (100%) of the double-crested cormorants that were satellite-tagged on East Sand Island and are still transmitting a signal were detected this week in the Columbia River estuary (defined for these purposes as the mouth of the Columbia River upriver to Puget Island)
7/9 – 7/15/12 ›
Night-time capture and banding of double-crested cormorant chicks with field-readable alphanumeric leg bands at the East Sand Island cormorant colony was concluded this week
7/9 – 7/15/12 ›
High count of Brandt’s cormorants this week on the East Sand Island colony was 2,567, about the same as last week’s high count (2,395); 933 active Brandt’s cormorant nests were counted this week, down from last week’s count of 1,010 nests; the oldest Brandt’s cormorant chicks are at least 35 days old and very mobile
7/9 – 7/15/12 ›
High count this week of about 12,725 Caspian terns on East Sand Island, similar to the previous week's high count of about 12,185 terns; low count this week was about 5,649 terns, down from last week's low count of about 6,553; about 440 tern chicks are estimated to survive on the colony this week
7/9 – 7/15/12 ›
Signs of multiple predators observed on East Sand Island; bald eagles were regularly seen on island but were causing fewer disturbances at the bird colonies as compared to previous weeks; bald eagles were seen killing an adult Brandt’s cormorants and a juvenile ring-billed gull; peregrine falcon seen daily at the east end of the island, mostly over the ring-billed gull colony
Weekly Update for 7/2 – 7/8/2012
7/6/12 ›
Survey of the Miller Sands Spit American white pelican colony; numerous chicks observed on-colony
7/3/12 ›
About 4,580 California brown pelicans counted roosting on East Sand Island, mostly on the shoreline near the south pile-dikes and adjacent to the Caspian tern colony on east end of island
7/2 – 7/8/12 ›
All previously failed areas on the East Sand Island double-crested cormorant colony remained unoccupied this week; the oldest cormorant chicks are roughly 35 days post-hatch, are mobile, and have developed flight feathers
7/2 – 7/8/12 ›
Dissuasion area on the East Sand Island double-crested cormorant colony was surveyed five days this week to confirm that no breeding cormorants were present; regular hazing events in the dissuasion area were not conductedthis week; large aggregations of double-crested cormorants (more than 3,000 individuals) observed roosting on exposed areas of the beach adjacent to the dissuasion area; large numbers of roosting cormorants (about 2,000 individuals) were also regularly observed on the Astoria-Megler Bridge this week, suggesting that failed breeders from East Sand Island are beginning to roost on the bridge
7/2 – 7/8/12 ›
Of the 77 currently active VHF radio-tagged double-crested cormorants, 49 (64%) were detected on East Sand Island at least once this week; two additional radio-tagged cormorants were detected on the Astoria-Megler Bridge
7/2 – 7/8/12 ›
This week, 11 of 11 (100%) of the double-crested cormorants that were satellite-tagged on East Sand Island and are still transmitting a signal were detected in the Columbia River estuary (defined for these purposes as the mouth of the Columbia River upriver to Puget Island)
7/2 – 7/8/12 ›
135 double-crested cormorant chicks were captured and banded with field-readable alphanumeric leg bands at East Sand Island cormorant colony
7/2 – 7/8/12 ›
High count of Brandt’s cormorants this week on the East Sand Island colony was 2,395, down from last week’s high count (2,669); 1,010 active Brandt’s cormorant nests were counted this week, similar to last week’s count of 1,020 nests
7/2 – 7/8/12 ›
High count this week of about 12,185 Caspian terns on East Sand Island, similar to the previous week's high count of about 12,295 terns; low count this week was about 6,553 terns, up from last week's low count of about 4,886; a second wave of chick hatching on the tern colony that began last week (7/1) continued this week; predation pressure by gulls remained high, with an estimated 40% of recently hatched tern chicks depredated by gulls
7/2 – 7/8/12 ›
Caspian terns continued to prospect and initiate new nests in and around the ring-billed gull colony on East Sand Island this week; additional dissuasion posts, ropes, and flagging were erected this week to limit expansion of tern nesting beyond the perimeter of the ring-billed gull colony
7/2 – 7/8/12 ›
Signs of multiple predators observed on East Sand Island; bald eagle activity regularly seen throughout the island; bald eagle disturbance to the East Sand Island Caspian tern colony continued; peregrine falcons flushed the tern colony during several evenings
Weekly Update for 6/25 – 7/1/2012
6/29/12 ›
Aerial survey of the Columbia River estuary and Willapa Bay (Grays Harbor not surveyed because of bad weather); main objectives of the flight were to (1) scan for radio-tagged cormorants from East Sand Island, (2) detect and photograph new and existing double-crested cormorant colonies, and (3) observe the American white pelican colony on Miller Sands Spit; see below for radio-tagged cormorant and American white pelican results; double-crested cormorant nests that were on range marker at Jetty “A” near Cape Disappointment had been removed
6/29/12 ›
Survey of the Miller Sands Spit American white pelican colony; 290 adults and 71 large chicks counted
6/26/12 ›
Joyce Casey, Sondra Ruckwardt, Diana Fredlund (U.S. Army Corps of Engineers), Michelle McDowell (U.S. Fish and Wildlife Service), Natalie St. John (The Daily News, Longview, WA), and Eric Wagner (University of Washington) visited East Sand Island
6/25 – 7/1/12 ›
All previously failed areas on the East Sand Island double-crested cormorant colony remained unoccupied this past week; there were very few loafing cormorants observed on colony at dusk and a decrease in numbers in the dissuasion area and on the beaches suggesting that failed cormorants may have left the island; the oldest cormorant chicks are roughly 28 days post-hatch, are mobile, and have developed flight feathers
6/25 – 7/1/12 ›
Dissuasion area on the East Sand Island double-crested cormorant colony was surveyed each day to confirm that no breeding cormorants were present; regular hazing events in the dissuasion area were not conductedthis week; large aggregations of double-crested cormorants (more than 3,000 individuals) observed roosting on exposed areas of the beach adjacent to the dissuasion area; large congregations of roosting cormorants (about 2,000) were also regularly observed on the Astoria-Megler Bridge this week, suggesting that failed breeders from East Sand Island are beginning to roost on the bridge
6/25 – 7/1/12 ›
Of the 80 currently active VHF radio-tagged double-crested cormorants, 46 (58%) were detected on East Sand Island at least once this week; five additional radio-tagged cormorants were detected at sites other than East Sand Island (3 on the Astoria-Megler Bridge, one in the upper Columbia River estuary, one in Willapa Bay)
6/25 – 7/1/12 ›
This week, 10 of 11 (91%) of the double-crested cormorants that were satellite-tagged on East Sand Island and are still transmitting a signal were detected in the Columbia River estuary (defined for these purposes as the mouth of the Columbia River upriver to Puget Island); one satellite-tagged cormorant was detected in Grays Harbor, WA
6/25 – 7/1/12 ›
High count of Brandt’s cormorants this week on the East Sand Island colony was 2,669, similar to last week’s high count (2,630); 1,020 active Brandt’s cormorant nests were counted this week, down slightly from 1,071 nests last week
6/25 – 7/1/12 ›
High count this week of about 12,295 Caspian terns on East Sand Island, similar to the previous week's high count of about 12,550 terns; low count this week was about 4,886 terns, similar to last week's low count of about 5,565; estimate of the number of active Caspian tern nests with chicks or eggs was roughly 4,000 -5,000; a second wave of chick hatching on the tern colony began on Sunday (7/1); there was a noticeable increase in aggression by adult terns directed at older tern chicks this week; chicks were frequently attacked and driven to the edge of the colony, where they were eventually killed by gulls
6/25 – 7/1/12 ›
Signs of multiple predators observed on East Sand Island; bald eagle activity regularly seen throughout the island; bald eagle disturbance to the East Sand Island Caspian tern colony continued; however, there were no prolonged flushes or major gull predation events on tern nests this week; peregrine falcon seen killing an adult Caspian tern on the south beach; fresh river otter tracks observed daily on north beach; bald eagle activity on the cormorant colony decreased again this week
Weekly Update for 6/18 – 6/24/2012
6/23/12 ›
About 93 active American white pelican nests counted on Miller Sands Spit
6/18 – 6/24/12 ›
Bald eagle disturbance tapered off at the East Sand Island double-crested cormorant colony this week; double-crested cormorants continued to reinitiate nests in several areas of the colony where nests failed earlier in the season; double-crested cormorant chicks observed that were old enough to leave the nest
6/18 – 6/24/12 ›
Hazing continued this week (8th consecutive week) on the dissuasion area on the East Sand Island double-crested cormorant colony; hazing events required on 5 days this week; cormorants continue to initiate nests within the dissuasion area east of the barrier fence; no cormorant eggs were detected in the dissuasion area this week; high count of about 800cormorants in the dissuasion area east of the barrier fence on Friday (6/22); large aggregations of double-crested cormorants (> 3,000 individuals) observed roosting on exposed areas of the beach mostly below the high tide line east of the barrier fence; disturbance to brown pelicans during hazing activities remained low this week, totaling about 300flushed individuals
6/18 – 6/24/12 ›
Of the 84 currently-active VHF-tagged double-crested cormorants, 60 (71%) were detected on East Sand Island at least once this week; two additional radio-tagged cormorants were detected on the Astoria-Megler Bridge that were not detected on East Sand Island; telemetry surveys looking for cormorants radio-tagged on East Sand Island were conducted at a cormorant colony on transmission towers on the Columbia River near Troutdale, Oregon and none were detected
6/18 – 6/24/12 ›
This week, 11 of 11 (100%) of the double-crested cormorants that were satellite-tagged on East Sand Island and are still transmitting a signal were detected in the Columbia River estuary (defined for these purposes as the mouth of the Columbia River upriver to Puget Island)
6/18 – 6/24/12 ›
High count of Brandt’s cormorants this week on the East Sand Island colony was 2,630, down from last week’s high count (2,890); 1,071 active Brandt’s cormorant nests were counted this week, up from 1,045 nests last week
6/18 – 6/24/12 ›
Bald eagle disturbance to the East Sand Island Caspian tern colony continued this week; no eagles were observed attempting to depredate adult terns on-colony this week; however, eagles continued to chase terns carrying fish and periodically flush sections of the tern colony
6/18 – 6/24/12 ›
High count this week of about 12,550 Caspian terns on East Sand Island, slightly higher than previous week's high count of 11,410 terns; low count for this week was about 5,565 terns, similar to last week's low count of 5,960; terns continued to initiate new nests and lay eggs in previously failed areas around the edge of the colony this week
6/18 – 6/24/12 ›
Caspian terns continued to prospect and initiate new nests in and around the ring-billed gull colony on East Sand Island this week; additional dissuasion posts, ropes, and flagging were erected this week to limit expansion of tern nesting beyond the perimeter of the ring-billed gull colony
6/18 – 6/24/12 ›
Signs of multiple predators observed on East Sand Island; bald eagle activity regularly seen throughout the island; a river otter flushed ca. 50-100 terns from the colony on 6/21
Weekly Update for 6/11 – 6/17/2012
6/17/12 ›
About 4,900 California brown pelicans counted roosting on East Sand Island, mostly adjacent to the Caspian tern colony on east end of island
6/15/12 ›
Aerial survey of the Willamette River (from Portland to Albany), the lower Columbia River (from the Portland to Astoria), and the Oregon Coast (from the Columbia River to Brookings); main objectives of the flight were to (1) scan for radio-tagged cormorants from East Sand Island, and (2) detect and photograph new and existing double-crested cormorant colonies; see below for radio-tagged cormorant results; active double-crested cormorant colonies observed at Whaleshead Cove Rock (near Brookings), Mack Reef and Hunter's Island (near the Pistol River), Redfish Rocks (near Port Orford), Gull Rock (at Cape Blanco), Table Rock (near Bandon), Cape Arago, Coos Bay (on several artificial structures), Bolon Island (near Reedsport), Haystack Rock (near Pacific City), Three Arch Rocks (near Oceanside), and Cape Lookout
6/11 – 6/17/12 ›
Bald eagle disturbance increased at the East Sand Island double-crested cormorant colony this week, with as many as 10 eagles observed on colony on Saturday (6/16); several areas where cormorants had reinitiated nesting failed again due to continued eagle disturbance
6/11 – 6/17/12 ›
Hazing continued this week (7th consecutive week) on the dissuasion part of the East Sand Island double-crested cormorant colony; only three hazing events required this week, as cormorants almost exclusively loafing in the dissuasion area; the high count of cormorants east of the barrier fence was about 500 on Tuesday (6/12); disturbance to brown pelicans during hazing activities declined again this week, totaling about 45flushed individuals; large aggregations of brown pelicans (> 500 individuals) continue to roost in the cormorant dissuasion area overnight
6/11 – 6/17/12 ›
Of the 89 currently-active VHF-tagged double-crested cormorants, 72 (81%) were detected on East Sand Island at least once this week; two additional radio-tagged cormorants were detected on the Astoria-Megler Bridge and one at Crimm’s Island that were not detected on East Sand Island; telemetry surveys looking for cormorants radio-tagged on East Sand Island were conducted along the outer Oregon coast, Willamette Valley (Portland to Albany), and Columbia River estuary and none were detected outside the Columbia River estuary
6/11 – 6/17/12 ›
This week, 11 of 11 (100%) of the double-crested cormorants that were satellite-tagged on East Sand Island and are still transmitting a signal were detected in the Columbia River estuary (defined for these purposes as the mouth of the Columbia River upriver to Puget Island)
6/11 – 6/17/12 ›
High count of Brandt’s cormorants this week on the East Sand Island colony was 2,890, higher than last week’s high count (2,122); 1,045 active Brandt’s cormorant nests were counted this week, up from 1,015 nests last week
6/11 – 6/17/12 ›
Bald eagle disturbance to the East Sand Island Caspian tern colony remained low for the third consecutive week; no eagles were observed attempting to depredate adult terns on-colony this week; however, predation pressure by gulls remained high, with most gulls now keying in on tern eggs and small chicks on the periphery of the tern colony
6/11 – 6/17/12 ›
High count this week of about 11,410 Caspian terns on East Sand Island, similar to last week's high count of 11,150 terns; low count for this week was about 5,960 terns, similar to last week's low count of 6,150; chicks continued to hatch this week; terns initiated new nests and laid eggs in previously failed areas around the edge of the colony this week
6/11 – 6/17/12 ›
Caspian terns continued to prospect and initiate new nests in and around the ring-billed gull colony on East Sand Island this week; dissuasion posts, ropes, and flagging were erected on three days this week to limit expansion of tern nesting beyond the perimeter of the ring-billed gull colony
6/11 – 6/17/12 ›
Signs of multiple predators observed on East Sand Island; bald eagle activity regularly seen throughout the island; river otter tracks found on beach; great horned owl feather found near ring-billed gull colony
Weekly Update for 6/4 – 6/10/2012
6/8/12 ›
Paul Schmidt and Cindy Boen with the U.S. Army Corps of Engineers, Holly Freifeld and Michelle McDowell with the U.S. Fish and Wildlife Service, Blaine Parker, Tom Skiles, and Simone Ballard with the Columbia River Inter-Tribal Fish Commission, and Lindsay Adrean with the Oregon Department of Fish and Wildlife visited East Sand Island
6/7/12 ›
First Brandt’s cormorant chick observed at East Sand Island cormorant colony
6/5/12 ›
Aerial survey of Columbia River estuary, Willapa Bay, Grays Harbor, the entire outer Washington coast, the Strait of Juan de Fuca, the Gulf and San Juan Islands, Puget Sound, and the Chehalis River; main objectives of the flight were to (1) scan for radio-tagged cormorants from East Sand Island, and (2) detect and photograph new and existing double-crested cormorant and Caspian tern colonies; see below for radio-tagged cormorant results; see Coastal Washington weekly update for status of Caspian tern breeding colonies
6/4 – 6/10/12 ›
Bald eagle disturbance tapered off dramatically at the East Sand Island double-crested cormorant colony this past week; several areas of the colony that failed earlier in the season reinitiated nests and had eggs by mid week; previously failed satellite colonies in the northwestern part of the colony were still being attended on Sunday (6/10); most of the renesting attempts by cormorants on the west jetty and nearby rip-rap have since failed due to continued eagle disturbance; all areas of the colony that did not fail earlier due to eagle disturbance now have chicks
6/4 – 6/10/12 ›
Hazing continued this week (6th consecutive week) on part of the East Sand Island double-crested cormorant colony, with an average of two hazing events per day (range: 1-4); very few hazing events were required early in the week; however, there was renewed prospecting in the dissuasion area later in the week, apparently due to an increase in bald eagle disturbances on the west jetty; the high count of cormorants east of the barrier fence was ~800 on Sunday (6/10); disturbance to brown pelicans during hazing activities declinedagain this week, totaling about 200flushed individuals; large aggregations of brown pelicans (> 1,500 individuals) continue to roost in the cormorant dissuasion area
6/4 – 6/10/12 ›
Of the 91 currently-active VHF-tagged double-crested cormorants, 83 (91%) were detected on East Sand Island at least once this week; two radio-tagged cormorants were detected on the Astoria-Megler Bridge and not on East Sand Island; telemetry surveys looking for cormorants radio-tagged on East Sand Island were conducted along the outer Washington coast, in the Salish Sea, and on the north coast of Oregon Coast from Astoria to Pacific City and none were detected
6/4 – 6/10/12 ›
This week, 10 of 11 (91%) of the double-crested cormorants that were satellite-tagged on East Sand Island and are still transmitting a signal were detected in the Columbia River estuary (defined for these purposes as the mouth of the Columbia River upriver to Puget Island); the other satellite-tagged individual is currently located near a recently active double-crested cormorant colony in Vancouver, B.C.
6/4 – 6/10/12 ›
High count of Brandt’s cormorants this week on the East Sand Island colony was 2,122, lower than last week’s high count (2,411); 1,015 active Brandt’s cormorant nests were counted this week, up from 866 nests last week
6/4 – 6/10/12 ›
Bald eagle disturbance to the East Sand Island Caspian tern colony remained low for the second consecutive week; no eagles were observed attempting to depredate adult terns on-colony this week; however, wet weather and continued nest predation by glaucous-winged/western gulls thinned portions of the tern colony; predation pressure by gulls remained intense, with most gulls now keying in on tern chicks; gulls opportunistically took chicks steadily throughout each day, even if the tern colony remained undisturbed; over 50% of the tern chicks in two productivity plots near the edge of the tern colony were taken by gulls on or before Sunday (6/10)
6/4 – 6/10/12 ›
High count this week of about 11,150 Caspian terns on East Sand Island, similar to last week's high of 10,900; low count for the week was about 6,150, similar to last week's low count of 5,880; chicks have been hatching all week and there were an estimated 1,000 tern chicks on colony by Sunday (6/10)
6/4 – 6/10/12 ›
Caspian terns continued to prospect and initiate new nests in and around the ring-billed gull colony on East Sand Island this past week; dissuasion posts, ropes, and flagging were erected on four days this week to limit expansion of tern nesting beyond the perimeter of the ring-billed gull colony; this satellite tern colony was photographed during the aerial survey on Tuesday (6/5); preliminary counts from photography indicated about 390 Caspian terns and 240 active tern nests at this satellite colony
6/4 – 6/10/12 ›
Signs of multiple predators observed on East Sand Island; bald eagle activity regularly seen throughout the island; river otter tracks found on the north beach
6/4/12 ›
5 adult double-crested cormorants were captured and banded with field-readable alphanumeric leg-bands at East Sand Island cormorant colony this week; a total of 125 breeding adult cormorants have been captured along the above-ground tunnel system at the East Sand Island colony and banded during the 2012 nesting season
Weekly Update for 5/28 – 6/3/2012
6/3/12 ›
First Caspian tern chick observed on East Sand Island tern colony
5/29/12 ›
5,623 California brown pelicans counted roosting on East Sand Island, mostly adjacent to the Caspian tern colony on the east and southeast beaches
5/28 – 6/3/12 ›
There was intense bald eagle activity on the East Sand Island double-crested cormorant colony again this week, with as many as 19 eagles observed on colony on Wednesday (5/29); widespread colony failure occurred this week accounting for about 25% of the season’s total nest failures to date; from Monday through Wednesday (5/28-5/30) groups of up to eight eagles, adults and sub-adults, were observed walking through the colony eating cormorant eggs and occasionally adult cormorants;gulls and ravens followed the eagles, taking eggs and adding to the nest failure; cormorant chicks began hatching in earnest around the observation tower on Wednesday and Thursday (5/30 & 5/31); most of the remaining colony is in late incubation, with some late nest initiation continuing on the west jetty
5/28 – 6/3/12 ›
Hazing continued this week (5th consecutive week) on part of the East Sand Island double-crested cormorant colony, with an average of five hazing events per day (range: 4-7); cormorants continue to initiate nests within the dissuasion area east of the barrier fence; no cormorant eggs were detected in the dissuasion area this week; the high count of cormorants east of the wall was ~1,400 at first light on Monday (5/28); disturbance to brown pelicans during hazing activities declinedthis week, totaling 456 flushed individuals; large congregations of pelicans (> 800 by week’s end) began roosting throughout the dissuasion area this week
5/28 – 6/3/12 ›
89 (85%) of the 105 currently active VHF-tagged double-crested cormorants were detected on East Sand Island at least once this week; in total, 92 (88%) active transmitters were detected at least once this week, with three individuals detected on the Astoria-Megler Bridge and not on East Sand Island
5/28 – 6/3/12 ›
This week, 10 of 11 (91%) of the satellite-tagged double-crested cormorants from East Sand Island that are transmitting a signal were detected in the Columbia River estuary (defined for these purposes as the mouth of the Columbia River upriver to Puget Island); the other satellite-tagged individual is currently located near a recently active double-crested cormorant colony in Vancouver, B.C.
5/28 – 6/3/12 ›
73 adult double-crested cormorants were captured and banded with field-readable alphanumeric leg-bands at East Sand Island cormorant colony
5/28 – 6/3/12 ›
High count of Brandt’s cormorants on East Sand Island colony was 2,411 this week, higher than last week’s high count (2,052); 866 active Brandt’s cormorant nests were counted this week, up from 781 nests last week
5/28 – 6/3/12 ›
With no major disturbances this week, the East Sand Island Caspian tern colony settled down and filled in as the week progressed; the failed area along the north and west edges of the colony has started to fill back in, but nests are still sparse; the core of the colony has remained dense and relatively untouched by gulls; bald eagles have regularly chased terns with fish around and over the colony; during the daytime these flyovers generally cause mostly loafing terns to flush; evening disturbances to the tern colony have diminished considerably this week as compared to previous weeks
5/28 – 6/3/12 ›
High count this week of about 10,896 Caspian terns on East Sand Island, down slightly from last week's high of 12,277; low count for the week was about 5,885, down from last week's low count of 6,625; some Caspian terns that were prospecting for nest sites or initiating nests earlier in the season have apparently left the estuary
5/28 – 6/3/12 ›
For most of the week Caspian terns showed no interest in establishing or expanding satellite colonies on East Sand Island; ropes, posts, and flagging were expanded around the ring-billed gull colony on Sunday (6/3) in response to about 25 terns prospecting on the northern edge of the gull colony; the small tern colony within the gull colony is doing well with counts averaging about 150 individuals; the high nest count was 21 on Sunday (6/3), but obscured views make this a minimum count
5/28 – 6/3/12 ›
Signs of multiple predators observed on East Sand Island; bald eagle and peregrine falcon activity regularly seen; river otter tracks found on the north beach
Weekly Update for 5/21 – 5/27/2012
5/27/12 ›
First double-crested cormorant chicks heard on East Sand Island cormorant colony during night-time banding
5/25/12 ›
Aerial survey of Columbia River estuary, Willapa Bay, Grays Harbor, and northern Oregon Coast (Astoria to Pacific City); main objectives of the flight were (1) to detect the formation of new Caspian tern and/or double-crested cormorant colonies and (2) to scan for recently deployed radio tags placed on double-crested cormorants from East Sand Island; new Caspian tern colony detected in upland area of No Name Island in Grays Harbor, WA; 14 Caspian terns and 4-5 tern nests counted adjacent to newly formed ring-billed gull colony (40 active nests); see below for radio-tagged cormorant results
5/25/12 ›
About 155 active American white pelican nests (some with eggs) counted on Miller Sands Spit
5/21 – 5/27/12 ›
Daily hazing of double-crested cormorants in the dissuasion area east of the barrier fenceon East Sand Island increased this week concurrent with nest failure due to eagle depredation in the non-dissuasion part of the colony; an average of five hazing events were required per day (range: 3-7);cormorants continue to build nests within the dissuasion area; no cormorant eggs were detected in the dissuasion area this week; high count of cormorants east of the barrier fence was >2,000 at first light on Saturday (5/26); disturbance to California brown pelicans during cormorant hazing activities decreased this week, totaling 830 flushed (range: 30-250pelicans flushed/disturbance)
5/21 – 5/27/12 ›
99 (93%) of the 107 currently active VHF-tagged double-crested cormorants were detected on East Sand Island at least once this week; three additional VHF-tagged cormorants were detected multiple times on the Astoria-Megler Bridge this week (not on East Sand Island) and are thought to be nesting at the bridge colony; by week’s end 105 transmitters remained active; an aerial survey of the Columbia River estuary, Willapa Bay, Grays Harbor, and the North Oregon coast (Astoria to Pacific City) was conducted on Friday (5/25) to look for radio-tagged cormorants from East Sand Island; seven active transmitters were detected, and one failed transmitter was identified; of the active VHF-tagged cormorants detected, one was found in Grays Harbor, WA and the remaining six were found within the Columbia River estuary
5/21 – 5/27/12 ›
This week, 9 of 11 (82%) of the satellite-tagged double-crested cormorants from East Sand Island that are transmitting a signal were detected in the Columbia River estuary (defined for these purposes as the mouth of the Columbia River upriver to Puget Island); the other two satellite-tagged individualsare currently located near a recently active double-crested cormorant colony in Vancouver, B.C. and in Grays Harbor, WA
5/21 – 5/27/12 ›
47 adult double-crested cormorants were captured and banded with field-readable alphanumeric leg-bands at East Sand Island cormorant colony
5/21 – 5/27/12 ›
Aerial photography of the cormorant colony on East Sand Island taken on 5/19 was counted to estimate double-crested cormorant colony size in late incubation; more than 14,000 attended cormorant nestswere counted; minimum estimates of Brandt’s cormorant nests on-colony (based on counts from ground) on 5/19 was 722; we estimate that at least 12,500 attended double-crested cormorant nests were present on the colony on 5/19; bald eagle activity has prevented re-nesting on the western-most portion of the East Sand Island cormorant colony; there has been some expansion and formation of new satellite cormorant colonies
5/21- 5/27/12 ›
99 PIT-tagged fish were fed to double-crested cormorants nesting on East Sand Island to determine rate at which consumed PIT-tagged fish are deposited on-colony
5/21 – 5/27/12 ›
High count of Brandt’s cormorants on East Sand Island colony was 2,052 this week, higher than last week’s high count (1,873); 781 Brandt’s cormorant nests were counted this past week, up from 698 nests last week
5/21 – 5/27/12 ›
Bald eagles caused 3 major disturbances to the East Sand Island Caspian tern colony this week; by the end of the week about a 10-meter band along the northern edge and within 30 meters of the western corner of the colony had failed; an estimated 15 – 25% of the total 1.57-acre core colony area has failed or is unoccupied; approximately 750 to 1,500 tern eggs were lost to gulls during eagle disturbances this week; despite large egg losses, several thousand tern nests with eggs persisted; the tern colony has settled down since Thursday's eagle disturbances, but was far more prone to flush this week
5/21 – 5/27/12 ›
High count this week of 12,270 Caspian terns on East Sand Island, about the same as last week's high of 12,160; low count for the week was 6,630, down from last week's 8,790
5/21 – 5/27/12 ›
Two of the three satellite Caspian tern colonies on East Sand Island failed this week; terns abandoned the south beach satellite colony after two days of high winds and tides on Monday and Tuesday (5/21 & 5/22); the west end satellite colony failed on Wednesday (5/23) due to frequent disturbance by eagles and the encroaching cormorant colony; the small satellite tern colony among nesting ring-billed gulls on the east end of the island persists, but counts have fluctuated; the high count of terns on this colony was 148 individuals this past week, similar to last week’s high count (150)
5/21 – 5/27/12 ›
Two Caspian tern carcasses were found on the southeastern tip of East Sand Island that appeared to have been killed by a peregrine falcon
Weekly Update for 5/14 – 5/20/2012
5/19/12 ›
Aerial photo census to estimate the number of active double-crested cormorant nests on the East Sand Island cormorant colony
5/14 – 5/20/12 ›
Daily hazing of double-crested cormorants in the dissuasion area east of the barrier fence continued this week, with an average of two hazing events per day (range: 1-3); no cormorant eggs were collected this week, nor were any believed to have been laid in the dissuasion area; the maximum double-crested cormorant count east of the barrier fence this week was about 1,000, counted at first light on Thursday (5/17); California brown pelican disturbance during cormorant hazing activities increased this week in response to cormorants building nests in the dissuasion area east of the main pile dike; pelicans were disturbed on three different occasions, totaling 1,950 displaced birds (range: 150-1000 pelicans flushed/disturbance)
5/14 – 5/20/12 ›
111 (95%) of the 117 currently active VHF-tagged double-crested cormorants were detected on East Sand Island at least once this week, with 97 being detected on Saturday (5/19); two additional VHF-tagged cormorants were detected multiple times on the Astoria-Megler Bridge this week and not on East Sand Island; we believe these birds are nesting at the bridge colony due to frequent detections during both night and afternoon surveys; by week’s end 108 transmitters remained active; in response to abandonment of portions of the East Sand Island colony caused by bald eagles early in the week (only 82 transmitters were detected on Tuesday night), we conducted several surveys looking for VHF-tagged cormorants away from East Sand Island; no VHF-tagged cormorants were located at historical and active cormorant colonies in the Salish Sea region, along the north Oregon Coast (Youngs Bay to Three Arches Rock), in the upper Columbia River estuary (minus the 2 birds at the bridge colony), or at active cormorant colonies in the Columbia Plateau region of eastern Washington
5/14 – 5/20/12 ›
This past week, 10 of 11 (91%) of the satellite-tagged double-crested cormorants from East Sand Island that are transmitting a signal were detected in the Columbia River estuary (defined for these purposes as the mouth of the Columbia River upriver to Puget Island); the other satellite-tagged individual is currently located near a recently active double-crested cormorant colony in Vancouver, B.C.
5/14 – 5/20/12 ›
Ground-based counts of double-crested cormorants on East Sand Island are no longer possible given the size and distribution of birds on the island; most cormorants on the main colony are in late incubation, but nest initiation continues in some satellite colonies and in scattered areas throughout the main colony; most of the oldest nests have four or five eggs, but areas that initiated later, around the west blind, have mostly three egg nests
5/14 – 5/20/12 ›
There was renewed bald eagle activity this week on the East Sand Island double-crested cormorants colony, and several sections of the colony failed as a result; by Monday (5/14) an estimated 1,500 nests failed along the rip-rap west of the western-most observation blind and in the western satellite colonies; cormorants are periodically reinitiating in failed areas, but are still prone to abandonment when eagles are present
5/14 – 5/20/12 ›
High count of Brandt’s cormorants on East Sand Island was 1,873 this week, higher than last week’s high count (1,450); roughly 698 Brandt’s cormorant nests were counted this past week, up from 450 nests last week
5/14 – 5/20/12 ›
The East Sand Island Caspian tern colony continued to settle down this past week; high count for the week was 12,160 on Thursday (5/17), up from last week's high of 11,550; low count was 8,786 on Wednesday (5/16), about the same as last week's 8,899; as of Sunday (5/20), there were several thousand tern nests with eggs; most nests have two eggs, but many have three; available habitat on the tern colony is very full and at least five terns were seen dumping eggs on flat ground between established nest scrapes; there was also renewed interest in the satellite tern colonies on the upper part of nearby beaches
5/14 – 5/20/12 ›
There are now three satellite Caspian tern colonies on East Sand Island, two on the east end of the island near the main Caspian tern colony, and one on the west end of the island near the cormorant colony; the satellite tern colony within the ring-billed gull colony at the east end grew to 150 terns attending 10 to 40 nests this week; the ring-billed gull colony has now been mostly encircled with dissuasion to prevent the tern colony from expanding beyond its outer perimeter; terns began showing increased interest in nesting in another satellite colony along the beach just to the southeast of the main tern colony on Tuesday and Wednesday (5/15 & 5/16); large sections of dissuasion posts, ropes, and flagging were erected along the south and east beaches this past week; on Friday morning (5/18) 12 eggs were discovered in 10 nests in marginal beach habitat just above the high tide line on the south beach; numbers of terns showing interest in this satellite colony declined from 700 - 1,000 terns on Friday (5/18) to about 50 terns with 5 attended nests with eggs on Sunday (5/20); the first tern egg was observed on the west end satellite tern colony on Wednesday (5/16) as it was depredated by a gull; by Friday (5/19) there were 317 terns and 22 well-formed nest scrapes at the west end satellite colony; despite a slight increase in size, this satellite tern colony is failing quickly due to very frequent disturbances, gull predation pressure, flooding, and incursion by nesting cormorants
5/14 – 5/20/12 ›
Bald eagles continued to chase Caspian terns transporting fish to the East Sand Island colony; despite this, colony flushes have become smaller and less frequent; most flushes only involved 5-10 percent of the tern colony, with larger flushes occurring about once every two days; gulls took between 5-10 eggs from tern nests located at the periphery of the colony during each small flush
5/14 – 5/20/12 ›
On Wednesday (5/16), 11 Caspian tern carcasses were found on the southeastern tip of East Sand Island, 10 of which appeared to have been killed by a peregrine falcon; the majority of these kills (8) were fresh, with at least one kill having occurred that same morning; these predation events likely explain the tern colony's late-evening and early-morning jumpiness
5/14 – 5/20/12 ›
Signs of multiple predators observed on East Sand Island; bald eagle and peregrine falcon activity regularly seen; fresh raccoon and river otter tracks found on the north beach
Weekly Update for 5/7 – 5/13/2012
5/11/12 ›
3,236 California brown pelicans counted roosting on East Sand Island, mostly on southeast beaches
5/10/12 ›
First Brandt’s cormorant egg observed on East Sand Island cormorant colony
5/7 – 5/13/12 ›
Daily hazing of double-crested cormorants in the dissuasion area on East Sand Island continued this week, with an average of four hazing events per day (range: 1-14); no eggs were collected, nor were any believed to have been laid; the high count of cormorants in the dissuasion area east of the barrier fence was about 1,500 at first light on Thursday (5/10); by week’s end just one hazing event was required per day to displace prospecting cormorants at first light; California brown pelican disturbance during cormorant hazing activities has been minimal, with daily flushes averaging < 100 pelicans (range: 0-250 pelicans)
5/7 – 5/13/12 ›
114 (93%) of the 122 currently active VHF-tagged DCCO were detected on East Sand Island at least once this week, with 105 (86%) being detected on Thursday (5/10); nine failed transmitters were detected throughout the week; by week’s end 117 transmitters remained active; as of 5/13 just three of the 126 transmitters deployed have not been detected at least once; 73 (58%) of the 126 VHF-tagged cormorants have been detected on East Sand Island at least once every week since deployment; no aerial or ground-based surveys were conducted this week to detect VHF-tagged cormorants away from East Sand Island
5/7 – 5/13/12 ›
As of Monday (5/14), all satellite-tagged double-crested cormorants from East Sand Island were detected in the Columbia River estuary (defined for these purposes as the mouth of the Columbia River upriver to Puget Island); to date, six individuals have visited locations outside of the Columbia River estuary based on preliminary data from the previous three weeks; a total of 12 satellite tags were placed on cormorants from East Sand Island; however, one tag is currently not transmitting
5/7 – 5/13/12 ›
Ground-based counts of double-crested cormorants on East Sand Island are no longer possible given the size and distribution of birds on the island; the colony has not expanded as dramatically this week as compared to the previous week, but all previously occupied areas continue to be used; the oldest nests had five eggs as of Thursday (5/10) and all productivity plots, including the West Blind plots, have nests with multiple eggs
5/7 – 5/13/12 ›
Bald eagle disturbance to the East Sand Island double-crested cormorant colony was minimal this week; only the western-most cormorants (on the west jetty) have been flushing regularly as bald eagles fly over the colony
5/7 – 5/13/12 ›
High count of Brandt’s cormorants on East Sand Island was 1,450 on Saturday (5/12), about the same as last week’s high count (1,432); roughly 450 active Brandt’s cormorant nests were counted this week
5/7 – 5/13/12 ›
With no major evening or nighttime disturbances, the East Sand Island Caspian tern colony continued to settle down and build nesting commitment this past week; the high count for the week was 11,550 on Friday (5/11), up from last week's count of 8,860; the low count was 8,899 on Monday (5/7), up from 4,465 last week and similar to last week's high count; the oldest tern eggs persisting on-colony were likely laid on Sunday (5/6); as of Sunday (5/13), there were over 1,000 nests with eggs and many nests with at least two eggs
5/7 – 5/13/12 ›
Bald eagle presence on the east end of East Sand Island has remained intense; although no direct attempts by eagles to take terns has been observed, several eagles have been perched almost continuously on pilings and channel markers within a sight of the tern colony and have been observed to regularly steal fish from terns as they return to colony; as eagles chase terns near the colony they cause partial colony flushes every hour or two; between five and twenty eggs are generally taken by gulls during each flush, mostly from nests located near the edge of the colony
5/7 – 5/13/12 ›
The East Sand Island Caspian tern colony has been especially jumpy in the evenings; every evening this week, 70-100% of the colony has flushed close to last light; we have not observed any predators during these flushes and terns have been returning to the colony quickly; terns have not been continuing to flush after these initial disturbances and have not abandoned; colony monitors spent evenings and nights in the blind from Tuesday (5/1) through Thursday (5/10), but did not observe any causes for late-evening or nighttime disturbances
5/7 – 5/13/12 ›
Two satellite Caspian tern colonies have formed or begun to form on East Sand Island this past week; small group of terns, 10-20 individuals, were first observed prospecting and scraping in a small area within the ring-billed gull colony on the east end of the island on Friday (5/11); these terns were flushed by researchers several times on Saturday (5/12); however, three tern eggs were found on Sunday (5/13); because of its proximity to the ring-billed gull colony, no further dissuasion for this satellite tern colony is planned at this time; a second satellite colony was first observed forming on the west end of the island, near the double-crested cormorant colony, on Thursday (5/10); on Thursday 200-300 terns were counted prospecting, scraping, copulating, and mate-feeding in an area of open sand and small driftwood just east of the tidal pond gully; on Saturday (5/11) and Sunday (5/12), five and 76 terns were sitting in scrapes, respectively; these terns have been very prone to eagle disturbance and do not return to scrapes for several minutes after each flush; as of Sunday (5/12), no eggs have been observed; because of the proximity of this potential satellite tern colony to nesting cormorants, no dissuasion is planned
5/7 – 5/13/12 ›
Signs of multiple predators observed on East Sand Island; bald eagles regularly seen; great horned owl tracks were observed on Sunday (5/13) on the north beach at a whimbrel kill; fresh raccoon tracks were also found on the North flats on Sunday (5/13)
Weekly Update for 4/30 – 5/6/2012
5/2/12 ›
First Caspian tern egg observed on East Sand Island tern colony
5/1/12 ›
On Tuesday night (5/1), during a disturbance to the East Sand Island Caspian tern colony caused by a bald eagle, about 40 Caspian tern decoys were quickly installed on the tern colony in two groups in an effort to encourage terns to remain on-colony during eagle disturbances and return quickly to the colony following a disturbance; about 80 additional tern decoys were placed on the tern colony on Saturday night; during subsequent disturbances, terns that had been flushed returned to areas of the colony with decoys first
4/30 – 5/6/12 ›
Daily hazing continued this week of double-crested cormorants attempting to build nests east of the barrier fence, in response to increased numbers of cormorants prospecting in the dissuasion area; no cormorant eggs were observed or collected in the dissuasion area this week; the high count of double-crested cormorants in the dissuasion area east of the barrier fence was 2,200 seen at first light on Wednesday (5/2); disturbance of California brown pelicans during cormorant hazing activities has been relatively minor this week, with daily flushes totaling < 100 pelicans
4/30 – 5/6/12 ›
101 of the 126 double-crested cormorants radio-tagged on East Sand Island (80%) were detected on East Sand Island at least once this week; 114 of the radio-tagged cormorants (90%) were detected at least once during either island surveys or aerial surveys to track radio-tagged cormorants
4/30 – 5/6/12 ›
Colony-wide high count for double-crested cormorants on East Sand Island this week was at least 12,000 on Sunday (5/6), up from 7,173 last week; this week's colony count includes only individuals in the non-hazed area of the colony west of the barrier fence; last week's double-crested cormorant high count west of the barrier fence was 3,019, about the same number as was estimated the previous week; the cormorant colony expanded very slowly early in the week until a notable influx of both double-crested cormorants and Brandt’s cormorants began on Wednesday (5/2); a dramatic expansion in cormorant colony size continued through Sunday (5/6); nesting double-crested and Brandt’s cormorants have filled in along the rip-rap and the combined colony is continuous from the barrier fence to about half way out the west jetty; new satellite cormorant colonies have been initiated in the dunes near the barrier fence and in the dunes north of the tidal pond; egg laying is occurring in all areas of the colony where nest building was initiated during the first wave of nest initiation two weeks ago; nest building is pervasive in areas of the cormorant colony first occupied this week
4/30 – 5/6/12 ›
Bald eagle disturbance to the East Sand Island double-crested cormorant colony was minimal this week; on Monday and Tuesday (4/30-5/1) there were several bald eagles around the colony, but cormorants were very committed and not prone to flush or leave their nests
4/30 – 5/6/12 ›
High count of Brandt’s cormorants on East Sand Island was 1,432 on Wednesday (5/2), up from 922 last week; an additional 346 were counted off colony; the main Brandt’s cormorant colony south of the tower blind is still growing, expanding mostly to the east along the rip-rap and on adjacent flat ground; Brandt’s cormorant on the colony were more committed and less prone to flush during bald eagle fly-overs; no Brandt’s cormorant eggs have been observed yet on-colony
4/30 – 5/6/12 ›
Caspian tern colony on East Sand Island appeared more settled this week during daytime hours; a major late-evening disturbance on Tuesday (5/1) began a series of nighttime disturbances, prolonged flushes, and partial colony abandonment; on Tuesday night (5/1), well after sunset, an adult bald eagle killed a single Caspian tern on-colony and remained on-colony for several minutes before flying with it's meal to the south beach; the disturbance caused all terns to abandon the colony until about 03:00 the following morning; terns stayed on colony the following night; on Thursday (5/3) about 20 terns laid eggs in their nests, but all eggs were depredated by gulls during several flushes that evening; beginning Thursday night (5/3) there were several clear, bright moon-lit nights; the tern colony was very unsettled and flushed frequently throughout these nights, but no direct causes were observed; from Thursday evening through Sunday morning (5/3-5/6) we estimate 100-300 tern nests containing eggs were lost to gull predation during disturbance events; the only tern nests with eggs that persisted on-colony at the end of the week (Sunday evening) were nests where egg-laying occurred on Sunday morning (5/6); high count for the week was 8,860 terns on Friday (5/4), similar to last week's high count of 9,090 terns; low count was 4,465 terns on Wednesday (5/2), up from last week’s low count of 2,316 terns
4/30 – 5/6/12 ›
At least one adult bald eagle has continued to kleptoparasitize (steal) fish from Caspian terns over the north and south beaches of East Sand Island, closer to the tern colony than ever before; this behavior, along with other daytime eagle fly-overs, caused 3-4 large flushes of the tern colony per day; terns have mostly returned quickly to the colony after daytime flushes by eagles
4/30 – 5/6/12 ›
Very high tides this week minimized the need for dissuasion of Caspian terns prospecting for nest sites on the beaches surrounding the East Sand Island tern colony; terns have continued to dig nest scrapes along beaches around the east end of the island, but mostly in unsuitable habitat well below the high tide line; several small areas around the ring-billed gull colony, which is adjacent to the main tern colony, were covered with ropes and flagging in response to prospecting terns; no tern eggs have yet been found off of the main colony on East Sand Island
4/30 – 5/6/12 ›
Signs of multiple predators observed on East Sand Island; bald eagles regularly seen; fresh raccoon tracks observed on the island this past week; an adult bald eagle killed a Caspian tern on colony this past week
Weekly Update for 4/23 – 4/29/2012
4/29/12 ›
First aerial survey of Columbia River estuary, Willapa Bay, and Grays Harbor; main objectives of the flight were (1) to detect the possible formation of new Caspian tern and/or double-crested cormorant colonies and (2) to scan for recently deployed radio tags placed on double-crested cormorants from East Sand Island; no new tern colonies were detected in the upper estuary, Willapa Bay, or Gray's Harbor; one small, previously undetected cormorant colony with four nests was observed on a channel marker off of the “A Jetty” in the Columbia River estuary near Cape Disappointment
4/29/12 ›
Count of 141 nesting American white pelicans (25 active nests with eggs) on Miller Sands Spit
4/29/12 ›
1,167 California brown pelicans counted roosting on East Sand Island, mostly on west jetty and west beach
4/26/12 ›
First double-crested cormorant egg observed on East Sand Island cormorant colony
4/23 – 4/29/12 ›
121 double-crested cormorants captured for tagging and banding in nest dissuasion area east of barrier fence on East Sand Island during the week; one adult cormorant fitted with a satellite tag and banded, 111 adult cormorants fitted with radio tags and banded, and 9 cormorants received bands only during the week; by end of week a total of 12 adult cormorants had been satellite-tagged, 128 adult cormorants had been radio-tagged, and 11 more had been banded; two of the deployed radio tags failed and were recovered, reducing the number of adult cormorants with active radio tags to 126; pre-breeding radio-tagging and satellite-tagging of adult cormorants on East Sand Island now completed for 2012; radio- and satellite-tagged cormorants will be tracked to monitor whether hazed individuals relocate and nest in undisturbed areas of East Sand Island or leave East Sand Island and attempt to nest elsewhere
4/23 – 4/29/12 ›
Full-time dissuasion of double-crested cormorants attempting to nest in the dissuasion area east of the barrier fence began on Saturday (4/28); one double-crested cormorant egg was found and collected under permit in the dissuasion area east of the barrier fence
4/23 – 4/29/12 ›
Seventy-seven of the 126 radio-tagged double-crested cormorants (61%) were detected on East Sand Island at least once post-deployment; 94 of the radio-tagged cormorants (75%) were detected at least once during either island or aerial surveys combined; 52 radio-tagged cormorants out of 126 (41%) were detected during the aerial survey on Sunday (4/29)
4/23 – 4/29/12 ›
Colony-wide high count for double-crested cormorants on East Sand Island was 7,173 on Tuesday (4/24), including about 4,400 individuals in the dissuasion area east of the barrier fence and 2,773 individuals in the undisturbed area west of barrier fence; beginning on Friday (4/27) dissuasion efforts regularly reduced numbers of cormorants east of the dissuasion barrier fence to zero; no obvious increase in numbers of double-crested cormorants nesting west of the barrier fence in the undisturbed area has been noted; egg-laying by cormorants nesting in the undisturbed part of the colony west of the barrier fence commenced on Saturday (4/28) and continues
4/23 – 4/29/12 ›
Bald eagle disturbance to the East Sand Island double-crested cormorant colony has been noted regularly in the evenings, but has been minimal during the day; a sub-adult eagle took a single double-crested cormorant on the north beach on Friday (4/27), causing a colony-wide disturbance; 10 or more bald eagles are usually present on west end of the island, mostly west of cormorant colony
4/23 – 4/29/12 ›
High count of Brandt’s cormorants on East Sand Island was 922 on Friday (4/27) with 915 west of the barrier fence and seven in the dissuasion area east of the barrier fence; Brandt’s cormorant colony still growing; nest initiation began in earnest on Saturday (4/28); colony has been especially prone to flushing during bald eagle flyovers
4/23 – 4/29/12 ›
Caspian tern colony on East Sand Island has grown and gradually became more settled on the 1.58-acre tern colony area this week; high count for the week was 9,090 on Sunday (4/29), up from 3,895 last week; low count was 2,316 on Tuesday (4/24); observations of copulation, nest scraping, and territorial scuffles have increased; some pairs have begun attending nest scrapes day and night, but no tern eggs have yet been observed; terns are filling up the prepared colony area and spilling out into the grass along the north edge of the colony during the evening
4/23 – 4/29/12 ›
Bald eagles continue to cause disturbances to the East Sand Island Caspian tern colony, but have only been flushing 20-30% of the colony this past week; adult and sub-adult eagles have regularly flown over the colony, but no attempts by eagles to depredate Caspian terns were observed; at least one adult eagle has been regularly attempting to steal fish from Caspian terns over the north beach
4/23 – 4/29/12 ›
Caspian terns showed their first interest this season in nesting at the satellite colony on the east end beach of East Sand Island on Friday (4/27), when 300 terns and 16 scrapes were counted; nest scraping continued through Saturday and Sunday, with a peak of 1,100 terns and 84 scrapes on Saturday (4/28); colony monitors walked through the satellite colony several times and erected dissuasion stakes and flagging; all nest scraping was well below the monthly high-tide line, but dissuasion is still warranted to prevent a satellite tern colony from forming and then expanding into habitat above the high-tide line; no tern eggs detected so far in satellite colony
4/23 – 4/29/12 ›
Signs of multiple predators observed on East Sand Island; bald eagles and peregrine falcons regularly seen; fresh river otter and raccoon tracks also observed on the island this past week; one gull carcass found, likely killed by an otter; two Caspian tern carcasses found, likely killed by peregrine falcon
Weekly Update FOR 4/16 – 4/22/2012
4/22/12 ›
Survey of cormorant colonies on the Astoria-Megler Bridge and upper estuary channel markers; double –crested cormorants have initiated nesting on four of eight channel markers near Miller Sands Spit and on Astoria-Megler Bridge; pelagic cormorants have also initiated nesting on the bridge
4/21/12 ›
Tidal lagoon on the west end of East Sand Island no longer being used by large numbers of roosting Caspian terns; no satellite Caspian tern colonies have been initiated on East Sand Island to date
4/19/12 ›
304 California brown pelicans counted on East Sand Island, up slightly from the previous week; most of the early season roosting pelicans are adults, suggesting they are failed breeders from southern California and/or Mexico
4/19 – 4/22/11 ›
30 double-crested cormorants captured for tagging and banding in nest dissuasion area east of barrier fence on East Sand Island; 11 adult cormorants fitted with satellite tags and banded, 17 adult cormorants fitted with radio tags and banded, and 2 cormorants received bands only; capture efforts cut short on two nights by late evening bald eagle disturbance events that resulted in total abandonment of the dissuasion area by cormorants; radio- and satellite-tagged cormorants will be tracked in subsequent weeks to monitor whether hazed individuals relocate to undisturbed areas on East Sand Island or leave East Sand Island altogether
4/18 – 4/22/12 ›
Continuous daytime monitoring of the dissuasion area on the East Sand Island double-crested cormorant colony began on 18 April; nest structures at the far east and west ends of the dissuasion area were dismantled on 22 April to delay the onset of egg-laying by potential early breeders, while allowing for continued capture of cormorants for radio- and satellite-tagging; no cormorant nests with eggs observed or suspected in the dissuasion area this week
4/18/12 ›
Colony monitors began continuous monitoring of East Sand Island Caspian tern and double-crested cormorant breeding colonies
4/17/12 ›
Count of 25-50 American white pelicans on area of Miller Sands Spit where nesting has occurred the previous two seasons; no PIT tags spread on-colony for smolt PIT tag detection efficiency studies to avoid disturbance to nesting pelicans
4/16 – 4/22/12 ›
Caspian terns started settling on the designated tern colony area on East Sand Island on 20 April; terns began digging nest scrapes immediately after their arrival on colony and have been observed courtship feeding and copulating; by the end of the week nearly 4,000 terns observed on-colony
4/16 – 4/22/12 ›
Caspian tern colony on East Sand Island flushed repeatedly by bald eagles during the day and remained unsettled and uncommitted, especially in the evening and at night; eagles have been observed attempting to steal fish from terns off-colony, but no successful attacks on Caspian terns observed; on 18 April a single mature eagle flew low over the length of the tern colony at dusk before attempting to take a gull on the east side of the tern colony area, a behavior very similar to what was observed leading up to the 2011 Caspian tern colony failure; a peregrine falcon was seen regularly attacking the ring-billed gull colony on the beach northeast of the tern colony; tern colony was abandoned during each of the first three nights (4/20 - 4/22), although most of the terns remained on-colony the night of 21 April; cause(s) of tern nocturnal colony abandonment not clear
4/16 – 4/22/12 ›
Double-crested cormorant colony on East Sand Island formed and grew rapidly this week; high count of double-crested cormorants on-colony was 7,500 on 21 April, with 4,500 individuals counted in the dissuasion area (east of barrier fence) and 3,000 individuals counted in the non-dissuasion area (west of the barrier fence); first double-crested cormorant courtship displays seen on 18 April; at least three adult double-crested cormorants killed by bald eagles on-colony this past week
4/16 – 4/22/12 ›
First Brandt’s cormorants observed on East Sand Island colony on 20 April; first Brandt’s cormorant courtship displays observed the following day; high count of Brandt’s cormorants on colony was 521 individuals and another 200 counted off-colony; all Brandt’s cormorants were observed west of the barrier fence, in the portion of the colony not slated for dissuasion
4/16 – 4/22/12 ›
Signs of multiple predators observed on East Sand Island; bald eagles and peregrine falcons regularly seen on the island and fresh otter tracks observed on the north and south beaches
Update FOR 3/6 – 4/15/2012
4/14/12 ›
Completion of East Sand Island colony preparations (e.g., building of observation blinds and tunnels, camp set up, laying out of colony grids, etc.)
4/14/12 ›
PIT tags sown for smolt PIT tag detection efficiency studies on East Sand Island cormorant and tern colonies
4/13 – 4/14/12 ›
Designated 1.58 acres of Caspian tern nesting habitat on East Sand Island treated with pre-emergent herbicide by USACE contractor to prevent growth of grass and broad-leaf weeds; area immediately surrounding the designated 1.58-acre colony area also treated with herbicide to prevent growth of broad leaf weeds and promote growth of native grasses in that area
4/12/12 ›
USACE contractor (Bear Power) completed construction of visual barrier fence on the East Sand Island double-crested cormorant colony; this feasibility study is designed to test whether cormorants can be dissuaded from nesting on ca. 62% of the former colony area used by nesting cormorants in 2010; if cormorants initiate nesting east of the fence they will be hazed prior it egg-laying; radio- and satellite-telemetry techniques will be used to monitor whether hazed individuals relocate to undisturbed areas on East Sand Island or leave East Sand Island altogether
4/2 – 4/15/12 ›
500 - 1,000 Caspian terns loafing on beaches at the east and west ends of East Sand Island
3/30/12 ›
First Caspian terns (2) observed on East Sand Island tern colony
3/27 – 4/15/12 ›
Caspian terns loafing and roosting in upland area just west of the tidal lagoon on the west end of East Sand Island; as many as 800 terns counted in this area; some nest scraping occurred and all nest scrapes were filled in on 2 April to help deter nesting there
3/27 – 4/15/12 ›
As many as 25 California brown pelican observed roosting on East Sand Island on 27 March; at least seven dead and mostly consumed pelican carcasses found on island during colony prep; unclear if pelicans died and were subsequently scavenged or if they were killed and eaten by bald eagles; about 12 -15 pelicans remained on East Sand Island on 14 April
3/27/12 ›
First double-crested cormorant (1) observed on East Sand Island colony
3/19/12 ›
First Caspian tern (1) sighted in Columbia River estuary by project staff in 2012; seen flying near East Sand Island
3/19/12 ›
Seasonal field crew began work in Columbia River estuary; beginning of East Sand Island colony preparations (e.g., building blinds and above-ground tunnels, camp set-up, laying out of grids on-colony, etc.)
3/17 – 4/15/12 ›
Signs of multiple predators observed on East Sand Island; as many as 15 bald eagles and a peregrine falcon have been observed on the island at one time; a common raven was observed capturing and wounding a roosting adult Caspian tern before being driven off by several American crows
3/17/12 ›
First California brown pelican (1) observed on East Sand Island; bird appeared to be sick or injured
3/17/12 ›
First Brandt’s cormorants sighted in Columbia River estuary by project staff in 2012; seen on pile dikes adjacent to East Sand Island
3/17/12 ›
First double-crested cormorants sighted in Columbia River estuary by project staff in 2012; seen flying near East Sand Island
3/15/12 ›
First California brown pelican (1) sighted in Columbia River estuary by project staff in 2012; seen flying near Tongue Point
3/12 – 3/14/12 ›
Nest dissuasion fences of landscape fabric erected around the East Sand Island Caspian tern colony site to limit the available Caspian tern nesting habitat to 1.58 acres
3/6/12 ›
1.58-acre area delineated for Caspian tern nesting habitat on East Sand Island; delineated area prepared (i.e., disked and smoothed) for nesting terns by USACE
