Weekly Update for 8/15 – 8/22/2011
8/15 – 8/22/11 ›
This completes our weekly reporting of field research activities in the Columbia River estuary for 2011
8/15/11 ›
Aerial photo census to estimate the number of double-crested cormorants attending the East Sand Island cormorant colony
Weekly Update for 8/8 – 8/14/2011
8/8 – 8/14/11 ›
No active Caspian tern nests on the East Sand Island tern colony; several thousand adult Caspian terns continue to roost on East Sand Island beaches
8/14/11 ›
14th census of California brown pelicans roosting on East Sand Island at dusk; ca. 8,094 brown pelicans counted on East Sand Island
8/14/11 ›
360 American white pelicans (ca. 70 chicks) counted at Miller Sands Spit colony
8/14/11 ›
Boat survey of upper Columbia River estuary; ca. 460 Caspian terns observed adjacent the old colony site on Rice Island; three tern chicks were counted; the USACE was notified and decided that no action would be taken at this stage of the breeding season
8/9/11 ›
PIT tags sown for smolt PIT tag detection efficiency study on East Sand Island tern colony
Weekly Update for 8/1 – 8/7/2011
8/1 – 8/7/11 ›
Final week of regular monitoring of piscivorous waterbird colonies in the Columbia River estuary in 2011
8/1 – 8/7/11 ›
High count of only 35 Caspian terns on the East Sand Island tern colony, down from 8,931 two weeks ago; Caspian terns were unsuccessful in rearing any young at East Sand Island this year
8/7/11 ›
13th census of California brown pelicans roosting on East Sand Island at dusk; ca. 14,150 brown pelicans counted on East Sand Island, more than double the number counted the previous week (ca. 6,925)
8/3/11 ›
75 American white pelicans (74 chicks and 1 adult) counted at Miller Sands Spit colony; this count is a minimum because the colony area is mostly obscured by vegetation
8/3/11 ›
Boat survey of upper Columbia River estuary; ca. 50 Caspian terns observed adjacent the old colony site on Rice Island; three tern nests containing a total of 2 eggs and 2 chicks were counted; the USACE was notified and decided that no action would be taken at this stage of the breeding season
8/1/11 ›
Aerial photo census to estimate the number of double-crested cormorants attending the East Sand Island cormorant colony
Weekly Update for 7/25 – 7/31/2011
7/25 – 7/31/11 ›
High count of only 253 Caspian terns on the East Sand Island tern colony, down from 8,931 last week; all tern nests with eggs failed due to gull predation during several disturbances by peregrine falcons and bald eagles; Caspian terns were unsuccessful in rearing any young at East Sand Island this year
7/31/11 ›
12th census of California brown pelicans roosting on East Sand Island at dusk; ca. 6,925 brown pelicans counted on East Sand Island, up from ca. 4,370 pelicans earlier this week
7/28/11 ›
Most double-crested cormorant chicks at the East Sand Island double-crested cormorant colony have either fledged or have left their nests to roost by the water
7/28/11 ›
High count for the week of 1,559 nesting Brandt’s cormorants, 823 attended nests with eggs or chicks on East Sand Island; this is a minimum count of active nests; several Brandt’s cormorant chicks have fledged and most chicks have left their nests to roost by the water
7/25/11 ›
11th census of California brown pelicans roosting on East Sand Island at dusk; ca. 4,370 brown pelicans counted on East Sand Island
Weekly Update for 7/18 – 7/24/2011
7/18 – 7/24/11 ›
Since complete colony failure on 1 June, thousands of Caspian terns have continued to roost on East Sand Island over-night; some terns continued attempts to re-nest; by end of the week all reinitiated tern nests with eggs had failed due to gull predation during several disturbances by peregrine falcons and bald eagles
7/18 – 7/24/11 ›
Disturbance and nest depredation rates at the East Sand Island double-crested cormorant colony were low compared to previous weeks; most cormorant chicks have either fledged or have left their nests to roost by the water
7/18 – 7/24/11 ›
High count for the week of 1,328 nesting Brandt’s cormorants, 817 attended nests with eggs or chicks on East Sand Island; this is a minimum count of active nests
7/21/11 ›
Continuous monitoring of East Sand Island Caspian tern and double-crested cormorant colonies discontinued; a reduced level of monitoring will continue at East Sand Island until late August or early September
Weekly Update for 7/11 – 7/17/2011
7/11 – 7/17/11 ›
East Sand Island Caspian tern colony was generally more settled this week compared to previous weeks; several newly reinitiated nests with eggs (some with two eggs) persisted throughout the week, unlike previous weeks where newly laid eggs persisted on the colony for only a few hours; over 100 tern nests remain active (with eggs) on the southeastern/central portion of the colony, despite frequent gull predation of tern eggs; terns are still prone to frequent disturbances by peregrine falcons and, apparently, great horned owls, but disturbances to the tern colony by bald eagles did not occur during the week
7/11 – 7/17/11 ›
For the past two weeks, disturbance and nest depredation rates at the East Sand Island double-crested cormorant colony were low compared to previous weeks; most cormorant chicks have either fledged or have left their nests to roost by the water
7/11 – 7/17/11 ›
High count for the week of 1,718 nesting Brandt’s cormorants, 825 attended nests with eggs or chicks on East Sand Island; this is a minimum count of active nests
7/11 – 7/17/11 ›
56 double-crested cormorant chicks captured and banded with field-readable alphanumeric leg bands at East Sand Island cormorant colony; in total, 400 double-crested cormorants were banded at the East Sand Island colony this year, including 216 adults and 184 juveniles
7/16/11 ›
10th census of California brown pelicans roosting on East Sand Island at dusk; ca. 7,650 brown pelicans counted on East Sand Island, up from ca. 5,610 pelicans the previous week
7/11/11 ›
78 American white pelican chicks were captured at the Miller Sands Spit colony; of these, 25 were banded with field-readable alphanumeric color bands and metal USGS bands, 26 were banded with metal bands only, and 27 were too small to band; during the colony walk through, 45 pelican nests and 101 pelican chicks were counted
7/11/11 ›
Paul Schmidt with the U.S. Army Corps of Engineers; Jenny Hoskins, Vanessa Loverti, and Paul Meyers with the U.S. Fish and Wildlife Service, and David Nuzum with the Oregon Department of Fish and Wildlife visited Miller Sands Spit to assist with chick banding at the America white pelican colony
7/11/11 ›
Boat survey of upper Columbia River estuary; ca. 100 Caspian terns observed adjacent the old colony site on Rice Island; three tern nests containing a total of 4 eggs were counted; the USACE was notified and decided that no action would be taken at this stage of the breeding season
Weekly Update for 7/4 – 7/10/2011
7/4 – 7/10/11 ›
Since complete colony failure on 1 June, thousands of Caspian terns continue to roost on East Sand Island over-night; numbers of roosting terns increased somewhat over the previous week; some terns continued attempts to re-nest; several newly initiated nests persisted for more than 24 hours before eggs were depredated by gulls (unlike previous weeks where newly laid eggs persisted on the colony for only a few hours); terns are still prone to frequent disturbances, but disturbances by bald eagles are down compared to previous weeks; it is unlikely that Caspian terns will be successful in rearing any young at East Sand Island this year
7/4 – 7/10/11 ›
Disturbance and nest depredation rates at the East Sand Island double-crested cormorant colony have declined from what was observed in previous weeks
7/4 – 7/10/11 ›
High count for the week of 1,857 nesting Brandt’s cormorants, 869 attended nests with eggs or chicks on East Sand Island; this is a minimum count of active nests
7/4 – 7/10/11 ›
85 double-crested cormorant chicks captured and banded with field-readable alphanumeric leg bands at East Sand Island cormorant colony
7/7/11 ›
An adult double-crested cormorant with Newcastle disease-like symptoms was collected and submitted for necropsy to pathologist Rob Bildfell, DVM, at the Oregon State University Veterinary Diagnostic Laboratory; the specimen was negative for Newcastle disease; attention has turned to potential botulism or domoic acid toxicity as the cause of illness
7/10/11 ›
9th census of California brown pelicans roosting on East Sand Island at dusk; ca. 5,610 brown pelicans counted on East Sand Island, down slightly from the previous week
7/9/11 ›
First double-crested cormorant fledgling observed at East Sand Island cormorant colony
7/6/11 ›
Nicole Tursich with Columbia River Inter-Tribal Fish Commission visited East Sand Island
Weekly Update for 6/27 – 7/3/2011
6/27 – 7/3/11 ›
Since complete colony failure on 1 June, thousands of Caspian terns continue to roost on East Sand Island over-night and some terns have attempted to re-nest, but most tern eggs are depredated by gulls within a few hours of laying; terns are still prone to frequent disturbances by bald eagles and peregrine falcons
6/27 – 7/3/11 ›
Disturbance rates on the East Sand Island double-crested cormorant colony have declined; however, nest failure and chick mortality continue to rise; as of 29 June, all sections of the main colony and satellite colonies west of the condo blind have failed; eagles were not the obvious cause of nest failure as eagle counts on colony have dropped; chicks may be dying from starvation or disease, as many chicks have been seen with symptoms consistent with Newcastle disease
6/27 – 7/3/11 ›
Brandt’s cormorants nesting on East Sand Island seem less prone to disturbance and nest failure than double-crested cormorants nesting on the same island; by end of the week, 1,644 individuals and 878 Brandt’s cormorant nests were counted, down slightly from the previous week; chicks began hatching on about 28 June in the section of the main colony where re-nesting occurred
6/27 – 7/3/11 ›
23 double-crested cormorant chicks captured and banded with field-readable alphanumeric leg bands at East Sand Island cormorant colony
7/3/11 ›
Eighth census of roosting California brown pelicans conducted on East Sand Island at dusk; ca. 5,660 brown pelicans counted on East Sand Island, down from ca. 6,500 brown pelicans counted on the island the previous week
Weekly Update for 6/20 – 6/26/2011
6/20 – 6/26/11 ›
Since complete colony failure on 1 June, thousands of Caspian terns continue to roost on East Sand Island over-night and some terns have attempted to re-nest, but most tern eggs are depredated by gulls within a few hours of laying; terns are still prone to frequent disturbances by bald eagles and peregrine falcons
6/20 – 6/26/11 ›
Roughly 15% of the East Sand Island double-crested cormorant colony has failed; cormorants that re-nested on the main colony west of the tower and in new areas on the west jetty and west beach have abandoned; recent colony failure can likely be attributed to a resurgence of eagle activity at the colony; as many as 9 eagles have been observed on the colony west of the tower this week
6/20 – 6/26/11 ›
Brandt’s cormorants nesting on East Sand Island seem less prone to disturbance and nest failure than double-crested cormorants nesting on the same island; by end of the week, 1,783 individuals and 893 Brandt’s cormorant nests were counted, nearly the same counts as the previous week
6/20 – 6/26/11 ›
60% (32/53) of radio-tagged double-crested cormorants captured in nest dissuasion area on East Sand Island were detected on island at sunset on 23 June, with all individuals located west of the dissuasion fence
6/20 – 6/26/11 ›
27 adult double-crested cormorants captured and banded with field-readable alphanumeric leg bands at East Sand Island cormorant colony; this concludes our banding of adult cormorants on East Sand Island; in total, 216 adults were banded (91 in the dissuasion area and 125 captured from the tunnel spurs west of the dissuasion fence)
6/20 – 6/26/11 ›
Three boat surveys of upper Columbia River estuary; on 20 June, ca. 100 Caspian terns were observed roosting adjacent the old colony site on Rice Island and 30 nest scrapes were counted during a walk-through of the area; on 24 June, no terns were observed in upland areas on Rice Island; on 26 June, 30 terns were observed at the old colony site on Rice Island, 3 of which were sitting in nest scrapes
6/26/11 ›
Seventh census of roosting California brown pelicans conducted on East Sand Island at dusk; ca. 6,500 brown pelicans counted on East Sand Island, down slightly from ca. 6,600 brown pelicans counted on the island the previous week
6/26/11 ›
110 American white pelicans, many with chicks (approximately 2-weeks old), counted at Miller Sands Spit colony; this count is a minimum because the colony area is mostly obscured by vegetation
6/26/11 ›
Aerial survey of upper Columbia River estuary, Willapa Bay, and Grays Harbor; 30 Caspian terns were observed on upland habitat on Rice Island and 14 terns at the South Bend Water Treatment Facility in Willapa Bay; counts of nesting double-crested cormorants on channel markers in the upper Columbia River estuary and in Grays Harbor were conducted
Weekly Update for 6/13 – 6/19/2011
6/13 – 6/19/11 ›
Since complete colony failure on 1 June, thousands of Caspian terns continue to roost on East Sand Island and some terns have attempted to re-nest, but most tern eggs are depredated by gulls within a few hours of laying; terns are still prone to frequent disturbances by bald eagles (see video) and peregrine falcons
6/13 – 6/19/11 ›
Bald eagle disturbance and egg depredation on the East Sand Island double-crested cormorant colony has remained relatively low compared to what was observed in late May; very few, if any, eggs are present in the sub-colonies that were abandoned several weeks ago; cormorants are re-nesting in the main colony area and in new areas where they have not nested for years (west jetty and west beach); several new nesting pairs have been observed taking over abandoned cormorant nests with chicks, first killing the abandoned chicks before reinitiating egg laying
6/13 – 6/19/11 ›
Bald eagle disturbance and egg depredation on the East Sand Island Brandt’s cormorant colony was not observed this past week; Brandt’s cormorant nests that did not fail during peak eagle disturbance in late May now have chicks; by the end of week, 1,727 individuals and 896 Brandt’s cormorant nests were counted
6/13 – 6/19/11 ›
74% (40/54) of radio-tagged double-crested cormorants captured in nest dissuasion area on East Sand Island were detected on island at sunset on 18 June, with all individuals located west of the dissuasion fence
6/13 – 6/19/11 ›
33 adult double-crested cormorants captured and banded with field-readable alphanumeric leg bands at East Sand Island cormorant colony
6/19/11 ›
Sixth census of roosting California brown pelicans conducted on East Sand Island at dusk; ca. 6,606 brown pelicans counted on East Sand Island, up from ca. 4,475 brown pelicans counted on the island the previous week
6/15/11 ›
Boat survey of upper Columbia River estuary; Caspian terns were not observed in any upland areas during the survey
6/15/11 ›
Four American white pelicans observed on colony at Miller Sands Spit; this count is a minimum because the colony area is mostly obscured by vegetation
Weekly Update for 6/6 – 6/12/2011
6/6 – 6/12/11 ›
Since complete colony failure on 1 June, thousands of Caspian terns continue to roost on East Sand Island and some terns have attempted to re-nest but most tern eggs are depredated by gulls within a few hours of laying; although the colony seems more settled than it has been in previous weeks, terns are still prone to frequent disturbance by bald eagles and peregrine falcons
6/6 – 6/12/11 ›
Bald eagle disturbance and egg depredation on the East Sand Island double-crested cormorant colony has remained relatively low compared to what was observed two weeks ago; cormorants are re-nesting in areas where previous nesting attempts had failed and in new areas where they have not nested for years (west jetty)
6/6 – 6/12/11 ›
Bald eagle disturbance and egg depredation on the East Sand Island Brandt’s cormorant colony was not observed this past week; Brandt’s cormorants continued to build new nests and by the end of week 1,855 individuals and 803 nests, most with eggs, were counted
6/6 – 6/12/11 ›
Satellite Caspian tern colony on upper beach near northeast tip of East Sand Island completely failed due to eagle disturbance and gull nest predation; the adjacent ring-billed gull colony is still active and most remaining gull nests have chicks
6/6 – 6/12/11 ›
75% (42/56) of radio-tagged double-crested cormorants captured in nest dissuasion area on East Sand Island were detected on island at sunset on 10 June, with all individuals located west of the dissuasion fence
6/11/11 ›
USACE contractor hired to both monitor Caspian tern activity and dissuade Caspian terns from nesting in the upper Columbia River estuary completed contract; project staff will continue monitoring Caspian tern activity in the upper estuary and will report and pre-nesting activity to the USACE
6/10/11 ›
Three bald eagles caused a large disturbance to thousands of roosting Caspian terns, hundreds of nesting double-crested cormorants, and hundreds of roosting California brown pelicans on west end of East Sand Island; an adult cormorant and an adult tern were killed by eagles during this disturbance; a bald eagle was also observed feeding on a California brown pelican carcass, although it is unknown whether the eagle killed the pelican
6/10/11 ›
Fifth census of roosting California brown pelicans conducted on East Sand Island at dusk; ca. 4,475 brown pelicans counted on East Sand Island, up from ca. 3,350 brown pelicans counted on the island the previous week
6/6/11 ›
Paul Schmidt, Chris Pinney, Dave Trachtenbarg, and Jessica Stokke with the U.S. Army Corps of Engineers, Jenny Hoskins with the U.S. Fish and Wildlife Service, Blaine Parker with Columbia River Inter-Tribal Fish Commission, and Dave Williams with USDA-Wildlife Services visited East Sand Island
Weekly Update for 5/30 – 6/5/2011
5/30 – 6/5/11 ›
Repeated evening/night-time disturbances by bald eagles to the East Sand Island Caspian tern colony occurred throughout the week, contributing to complete colony failure (i.e., no remaining tern eggs or chicks) on 1 June; thousands of terns are still roosting on East Sand Island and some terns have attempted to re-nest but most tern eggs are depredated by gulls within 30 minutes of laying
5/30 – 6/5/11 ›
Bald eagle disturbance and egg depredation on the East Sand Island double-crested cormorant colony decreased this past week; cormorants are re-nesting in areas where previous nesting attempts had failed and in new areas where they have not nested for years (west jetty)
5/30 – 6/5/11 ›
Bald eagle disturbance and egg depredation on the East Sand Island Brandt’s cormorant colony also decreased this past week; Brandt’s cormorants continued to build new nests and by the end of week 1,426 individuals and 671 new nests, most with eggs, were counted
5/30 – 6/5/11 ›
Caspian terns continued to dig nest scrapes on beaches near northeast tip of East Sand Island; a small satellite tern colony formed along the southeast perimeter of the ring-billed gull colony, where about 1,000 pairs of gulls are nesting; satellite tern colony peaked at 15 nests early in week, but was down to 5 active nests by end of week; ring-billed gull colony and satellite tern colony have been the focus of recent eagle disturbances once the main tern colony on East Sand Island failed; there are no plans for additional dissuasion around the existing satellite tern colony
5/30 – 6/5/11 ›
75% (42/56) of the radio-tagged double-crested cormorants captured in nest dissuasion area on East Sand Island were detected on island at sunset on 31 May, with all individuals located west of the dissuasion fence
5/30 – 6/5/11 ›
Small numbers of roosting double-crested cormorants were observed in the nest dissuasion area east of barrier fence on East Sand Island; no cormorant dissuasion action occurred this past week and no cormorant nests were initiated in the nest dissuasion area; nesting gulls are now widespread in the cormorant nest dissuasion area, most nests have eggs
6/4/11 ›
Fourth census of roosting California brown pelicans conducted on East Sand Island at dusk; ca. 3,350 brown pelicans counted on East Sand Island, up from ca. 2,900 brown pelicans counted on the island the previous week
6/4/11 ›
Aerial survey of Columbia River estuary, Willapa Bay, and Grays Harbor; Caspian terns were not observed in any upland areas during the survey, with the exception of East Sand Island and the northeast corner of Willapa Bay at the South Bend Water Treatment Facility near Raymond, WA (9 terns counted at the site, none were nesting); ca. 100 American white pelicans observed on colony at Miller Sands Spit, many of which appeared to be sitting on nests (no chicks visible)
5/31/11 ›
First Caspian tern chicks (2) observed on East Sand Island tern colony; both chicks were depredated by gulls within an hour of being first observed
5/31/11 ›
First double-crested cormorant chicks observed on East Sand Island tern colony; based on the size of the chicks when observed, it’s likely first hatching occurred on 29 May
5/30 – 5/31/11 ›
15 adult double-crested cormorants captured and banded with field-readable alphanumeric leg bands at East Sand Island cormorant colony
Weekly Update for 5/23 – 5/29/2011
5/23 – 5/29/11 ›
Unprecedented disturbance, nest predation, nesting failure, and colony abandonment has occurred at the East Sand Island Caspian tern, double-crested cormorant, and Brandt’s cormorant colonies (see below)
5/23 – 5/29/11 ›
Repeated evening/night-time disturbances by bald eagles to the East Sand Island Caspian tern colony occurred throughout the week; almost daily colony-wide disturbances caused by bald eagles attempting to depredate adult terns; these disturbance events are occurring earlier in the evening when it is still light, exacerbating gull predation on terns eggs in unattended nests; night time disturbance to the tern colony a by great horned owl also occurred; these disturbances and nest predation events coupled with heavy rainfall on 23 May resulting in significant flooding on the colony has caused unprecedented nest failure at the tern colony; the number of active tern nests with eggs has declined from ca. 5,000 to less than 500 over the past two weeks; only a small area near the center of the colony still has a concentration of active nests; see attached videos (colony disturbances on 5/28 and 5/29)
5/23 – 5/29/11 ›
Bald eagle disturbance and egg depredation on the East Sand Island double-crested cormorant colony continues to increase; groups of eagles observed walking through the colony during the day to take cormorant eggs; ca. 70% of double-crested cormorant nests west of the tower blind abandoned, including almost all nests in satellite colonies; all cormorant nests on the rip rap east of the tower blind have also been abandoned; double-crested cormorants are attempting to renest in these areas but face continued pressure from bald eagles causing adult cormorants to flush and leave nests unattended for entire day
5/23 – 5/29/11 ›
Due to intense bald eagle disturbance and egg depredation, the number of Brandt’s cormorants counted on the East Sand Island colony on 23 May was down to less than 100, a drastic reduction from the ca. 1,150 counted in the previous week; only 5-10 active Brandt’s cormorant nests remained; Brandt’s cormorants continued to build new nests and by the end of the week 1,087 individuals and 427 new nests were counted
5/23 – 5/29/11 ›
Caspian terns continued to dig nest scrapes on beaches around northeast tip of East Sand Island; a small satellite tern colony has formed along the southeast perimeter of the ring-billed gull colony; 140 Caspian terns, 2 tern nests with eggs, and 12 tern nests with depredated eggs were counted in this area at the end of the week; further growth of this satellite colony should be limited by the adjacent ring-billed colony and the previously erected dissuasion; due to the high rates of nest failure occurring at the main tern colony on East Sand Island this year (described above), there are no plans for additional dissuasion around the existing satellite colony
5/23 – 5/29/11 ›
73% (41/56) of the radio-tagged double-crested cormorants captured in nest dissuasion area on East Sand Island were detected on island at sunset on 29 May, with all individuals located west of the dissuasion fence; since the major colony abandonment event (see above), 6 radio-tagged cormorants that were previously detected on East Sand Island have left the island
5/23 – 5/29/11 ›
High count of 98 roosting double-crested cormorants in nest dissuasion area east of barrier fence on East Sand Island; no hazing of cormorants in the nest dissuasion area occurred this past week
5/24 – 5/29/11 ›
43 adult double-crested cormorants captured and banded with field-readable alphanumeric leg bands at East Sand Island cormorant colony
5/28/11 ›
Aerial photo census to estimate the number of breeding pairs of Caspian terns on the East Sand Island tern colony and the number of double-crested cormorants attending the East Sand Island cormorant colony
5/28/11 ›
Third census of roosting California brown pelicans conducted on East Sand Island at dusk; ca. 2,900 brown pelicans roosting on East Sand Island at night, up from ca. 2,100 brown pelicans counted on the island the previous week
5/25/11 ›
Corps contractor hired to prevent Caspian tern nesting in the upper estuary report an increase in numbers of Caspian terns and double-crested cormorants on Rice Island, perhaps associated with the disturbance and nest failure occurring on East Sand Island colonies (see above); to date, Caspian terns have not nested at any of the upper estuary dredge spoil islands (i.e., Rice Island, Miller Sands Spit, and Pillar Rock Sands)
5/23/11 ›
Quinton Smith and James Francis from The Oregonian visited East Sand Island
Weekly Update for 5/16 – 5/22/2011
5/16 – 5/22/11 ›
Beginning the evening/night of 16 May, repeated evening/night-time disturbances to the East Sand Island tern colony occurred throughout the week; disturbances were caused by a great horned owls, bald eagles, and peregrine falcons, with predation on adult terns confirmed by all three predator species this past week; disturbances caused all terns to abandon the colony for 3-6 hours before returning to their nests; depredation by gulls on tern eggs in unattended nests was significant, with most of the eggs in tern nests at the perimeter and in the western and eastern portion of the colony being depredated; most tern nests initiated to date on East Sand Island have failed due to egg predation
5/16 – 5/22/11 ›
Bald eagle presence and egg depredation on the double-crested cormorant colony on East Sand Island continues to increase
5/16 – 5/22/11 ›
Caspian terns continued to dig nest scrapes on beaches around northeast tip of East Sand Island; 7 tern eggs laid on beach this past week, 5 of which were subsequently lost during high tide or to gull predation; incipient satellite tern colony staked and flagged to discourage tern nesting
5/16 – 5/22/11 ›
Roughly 1,133 Brandt’s cormorants counted on East Sand Island colony, ca. 550 attending nests
5/16 – 5/22/11 ›
91% (51/56) of the radio-tagged double-crested cormorants captured in nest dissuasion area on East Sand Island were detected on island at least once this past week; 88% (49/56) of radio-tagged birds were detected on-colony west of the dissuasion area on the evening of 17 May; some, if not most, of these cormorants are attempting to re-nest on East Sand Island outside nest dissuasion area; 7% (4/60) of the radio-tagged cormorants are believed to have lost their tags
5/16 – 5/22/11 ›
High count of 240 roosting double-crested cormorants in nest dissuasion area east of barrier fence on East Sand Island; cormorants were hazed off the nest dissuasion area once this past week when <10 cormorants were observed bringing nesting material to the site; egg laying by cormorants did not occur in the nest dissuasion area; it appears that infrequent hazing will be necessary to prevent double-crested cormorants from re-nesting in the nest dissuasion area
5/16 – 5/22/11 ›
Numerous bald eagles observed throughout East Sand Island causing terns and cormorants to flush from their colonies and depredating eggs from cormorant nests; several species of avian predators (great horned owls, bald eagles, peregrine falcons, and common ravens) have killed adult terns on the East Sand Island tern colony this past week; egg depredation by gulls at the East Sand Island tern colony increased dramatically this past week (see above)
5/20/11 ›
Second census of roosting California brown pelicans conducted on East Sand Island at dusk; ca. 2,100 brown pelicans roosting on East Sand Island at night, up from ca. 1,350 brown pelicans counted on the island the previous week
5/19 – 5/20/11 ›
17 adult double-crested cormorants captured and banded with field-readable alphanumeric leg bands at East Sand Island cormorant colony
Weekly Update for 5/9 – 5/15/2011
5/9 – 5/15/11 ›
Caspian terns digging scrapes in driftwood and on beach around the southeast and northeast tip of East Sand Island; 10 tern eggs laid on beach and all subsequently depredated by gulls; incipient satellite tern colony staked and flagged to discourage tern nesting
5/9 – 5/15/11 ›
Roughly 919 Brandt’s cormorants counted on East Sand Island colony, ca. 315 attending nests
5/9 – 5/15/11 ›
93% (52/56) of the radio-tagged double-crested cormorants captured in nest dissuasion area on East Sand Island were detected on island at least once this past week; 86% (49/56) of radio-tagged birds were detected on-colony west of the dissuasion area on 11 May; some, if not most, of these cormorants are attempting to re-nest on East Sand Island outside nest dissuasion area; 7% (4/60) of the radio-tagged cormorants are believed to have lost their tags
5/9 – 5/15/11 ›
High count of 188 roosting double-crested cormorants in nest dissuasion area east of barrier fence on East Sand Island; cormorants were not hazed off the nest dissuasion area this past week to test the level of effort necessary to prevent nesting; no nesting attempts by cormorants were initiated in the nest dissuasion area; it appears that continued active hazing will not be necessary to prevent double-crested cormorants from nesting in the nest dissuasion area
5/9 – 5/15/11 ›
Signs of multiple predators observed on East Sand Island; bald eagles observed at both ends of the island causing terns and cormorants to flush from their colonies; 8 Caspian tern carcasses observed on east beach, two likely depredated by a common raven, two likely depredated by a bald eagle, and the cause of death of the others is unknown; 1 Caspian tern carcass observed near the field camp located in the center of the island, likely killed by a mammalian predator; fresh river otter and raccoon tracks observed on the island, but not near the tern colony
5/15/11 ›
High count for Caspian terns on the 2-acre colony site at East Sand Island of 13,583 terns, down from 14,242 terns the previous week; the colony appears to have peaked in size, with the nesting habitat prepared for terns nearly completely occupied by nesting terns; most terns are attending nests with eggs
5/13/11 ›
First census of roosting California brown pelicans conducted on East Sand Island at dusk; 1,330 brown pelicans roosting on East Sand Island at night, down from 2,546 brown pelicans counted on the island on this same date last year
Weekly Update for 5/2 – 5/8/2011
5/2 – 5/8/11 ›
Caspian terns digging scrapes adjacent to the ring-billed gull colony on beach on the northeastern tip of East Sand Island; incipient satellite tern colony staked and flagged to discourage tern nesting
5/2 – 5/8/11 ›
Nest initiation on East Sand Island double-crested cormorant colony highly asynchronous; nesting cormorants in some areas of colony have multiple eggs, while in other areas eggs have not been laid
5/2 – 5/8/11 ›
Roughly 740 Brandt’s cormorants counted on East Sand Island colony, ca. 190 attending nests
5/2 – 5/8/11 ›
97% (57/59) of radio-tagged double-crested cormorants captured in nest dissuasion area on East Sand Island were detected on island at least once this past week; 90% (53/59) of radio-tagged birds were detected on-colony west of the dissuasion area on 5 May; some, if not most, of these cormorants are attempting to re-nest on East Sand Island outside nest dissuasion area
5/2 – 5/8/11 ›
High count of 203 double-crested cormorants in nest dissuasion area east of barrier fence on East Sand Island; roosting cormorants hazed off the nest dissuasion area by repeated forays into the dissuasion area by project personnel; it appears that active hazing may be successful in preventing cormorants from nesting in nest dissuasion area east of barrier fence without disrupting cormorants nesting west of barrier fence
5/2 – 5/8/11 ›
Signs of multiple predators observed on East Sand Island; bald eagles observed at both ends of the island causing terns and cormorants to flush from their colonies; immature bald eagles have been observed taking eggs from cormorant nests; 4 Caspian tern carcasses observed on east beach, one likely depredated by a common raven, all others killed by unknown predator; fresh river otter and raccoon tracks observed on the island, but not near the tern colony
5/4/11 ›
High count for Caspian terns on the 2-acre colony site at East Sand Island of 14,242 terns; nesting habitat prepared for terns this year nearly completely occupied by nesting terns; most breeding pairs have yet to initiate incubation
5/4/11 ›
PIT tags sown for smolt PIT tag detection efficiency study in areas on East Sand Island used by roosting California brown pelicans
5/3/11 ›
Aerial survey of Columbia River estuary, Willapa Bay, and Grays Harbor; Caspian terns observed in upland areas on Rice Island near the former colony site (ca. 200) and on northwest corner of Rice island (ca. 75); Caspian terns continue to roost on two piers at Tongue Point (ca. 175); nine Caspian terns observed on a dike at the Willapa Wastewater Treatment Facility located adjacent the Willapa River in northeast corner of Willapa Bay, one of which appeared to be attending a nest; Caspian terns not observed at any other upland areas in the Columbia River estuary, Willapa Bay, or Grays Harbor
5/3/11 ›
Count of 49 American white pelicans on Miller Sands Spit, 22 of which appeared to be attending nests; 2010 was the first year that American white pelicans were recorded nesting in the Columbia River estuary
5/2/11 ›
USACE contractor began passive and active hazing of Caspian terns attempting to nest in the upper Columbia River estuary; the contractor plans to conduct frequent (i.e., every other day) visits to all sites in the upper estuary where terns might nest, and once prospective nest sites are found, haze terns off the site(s)
Weekly Update for 4/25 – 5/1/2011
4/25 – 5/1/11 ›
Boat surveys of upper Columbia River estuary; Caspian terns continue interest in nesting on Rice Island; additional stakes and flagging erected on Rice Island in areas where terns dug scrapes (near the former colony site and on northwest corner of island); Caspian terns now roosting on two piers at Tongue Point (used only one pier in previous weeks); USACE notified about situation
4/25 – 5/1/11 ›
Signs of multiple predators observed on East Sand Island; bald eagles observed at both ends of the island causing terns and cormorants to flush from their colonies; common ravens depredated at least two adult terns; fresh river otter and raccoon tracks observed near tern colony; several night time disturbances to the tern colony occurred, perhaps caused by nocturnal visits to tern colony by great horned owl, raccoon, or river otter
4/26 – 5/1/11 ›
Caspian terns digging nest scrapes (25) on beach near southeastern tip of East Sand Island; incipient satellite tern colony staked and flagged to discourage tern nesting
4/29 – 5/1/11 ›
Double-crested cormorants attempting to nest in nest dissuasion area east of barrier fence on East Sand Island hazed from area; ca. 800 cormorants flushed from the nest dissuasion area on 29 April and all existing nest structures redistributed; in subsequent 2 days, roosting and nesting cormorants hazed off the nest dissuasion area by repeated forays into the dissuasion area by project personnel; nesting attempts by cormorants in nest dissuasion area diminished on each successive day of active hazing; early result suggest active hazing may be successful in preventing cormorants from nesting in nest dissuasion area east of barrier fence without disrupting cormorants nesting west of barrier fence
4/29/11 ›
6 double-crested cormorants captured for banding on East Sand Island force-fed PIT-tagged fish to verify retention until bird’s release; 5 of 6 cormorants did not regurgitate PIT-tagged fish prior to release, suggesting this method may be effective in measuring off-colony deposition rates of PIT-tagged fish by double-crested cormorants
4/25 – 4/29/11 ›
92 double-crested cormorants captured for radio-tagging and banding in the nest dissuasion area east of barrier fence on East Sand Island; all 92 banded with engraved color bands and USGS metal bands and 60 also outfitted with tail-mounted radio transmitters; 51 of 60 radio-tagged cormorants detected at least once post-release on East Sand Island, mostly outside dissuasion area west of barrier fence and on surrounding beaches
4/29/11 ›
First Caspian tern eggs (multiple one-egg nests) observed on East Sand Island tern colony
4/26/11 ›
First double-crested cormorant eggs observed on East Sand Island cormorant colony; 2 eggs in one nest, suggesting first egg was laid on 25 April
Weekly Update for 4/18 – 4/24/2011
4/18 – 4/24/11 ›
High count of 8,170 Caspian terns on East Sand Island colony; nesting behaviors (i.e., nest scraping, copulations, courtship feeding) observed but no eggs laid
4/18 – 4/24/11 ›
Reinforced tern nest dissuasion fences on East Sand Island are showing no signs of wear or tear; no terns have attempted to nest in the areas where the fences and flagging have been erected
4/18 – 4/24/11 ›
Signs of multiple predators observed on East Sand Island; bald eagles observed at both ends of the island with at least three adult double-crested cormorants depredated by eagles on colony; peregrine falcon killed and consumed an adult tern on colony causing terns to abandon the colony for roughly 24 hours; common ravens caused the Caspian tern colony to flush at least twice; fresh river otter tracks observed near the tern colony and two depredated gulls collected near the former otter den site; 6 depredated Caspian terns collected with signs consistent with avian predation; great horned owl heard calling on the island; fresh raccoon tracks seen in the upland swamp near the tern camp
4/18 – 4/24/11 ›
Roughly 8,000 double-crested cormorants counted on the East Sand Island colony, ca. 500 in nest dissuasion area east of fence and available for capture and tagging as part of nest dissuasion experiment; nesting behaviors (i.e., nest building, courtship) observed but no eggs laid
4/18 – 4/24/11 ›
High count of 390 Brandt’s cormorants on the East Sand Island colony
4/23 – 4/24/11 ›
Boat surveys of upper Columbia River estuary; up to 300 loafing Caspian terns observed on upland area of Rice Island adjacent to area staked and flagged on 20 April; area used by terns is vegetated and does not appear to be suitable for nesting; no courtship behaviors or tern nest scrapes observed; Caspian terns (ca. 150) also counted on Tongue Point pier
4/23/11 ›
PIT tags sown for smolt PIT tag detection efficiency study on Miller Sands Spit American white pelican colony
4/22/11 ›
First California brown pelicans (5) observed on East Sand Island by project staff in 2011
4/22/11 ›
First American white pelicans (32) observed on Miller Sands Spit by project staff in 2011; pelicans observed near colony site used in 2010; no nests observed
4/22/11 ›
Boat survey of upper Columbia River estuary; no Caspian terns observed in upland areas of Rice Island; Caspian terns (ca. 150) counted on Tongue Point pier
4/20/11 ›
Boat survey of upper Columbia River estuary; ca. 200 Caspian terns observed on upland area of Rice Island; courtship behavior observed and tern nest scrapes (60) counted; incipient tern colony on Rice Island staked and flagged to discourage tern nesting; Caspian terns (ca. 150) also counted on Tongue Point pier
4/18/11 ›
Boat survey of upper Columbia River estuary; 40 Caspian terns observed on upland area of Rice Island along the southern edge of former colony site; ca. 150 Caspian terns observed on a pier at Tongue Point; courtship behavior and nest scrapes observed at both sites; USACE notified about situation
Weekly Update for 4/11 – 4/17/2011
4/11 – 4/17/11 ›
Signs of multiple predators observed on East Sand Island; bald eagles observed at both ends of island; at least two adult double-crested cormorants depredated by eagles on colony; a common raven mortally wounding an adult Caspian tern on the beach near the tern colony; fresh river otter tracks (2 individuals) observed leading to and from the tern colony; 6 depredated Caspian terns collected with signs consistent with otter predation; fresh great horned owl tracks observed on the beach east of the tern colony; several night time disturbances to the tern colony occurred, perhaps caused by night time visits to the tern colony by great horned owl or river otter
4/15/11 ›
Reinforced nest dissuasion fences erected adjacent to the East Sand tern colony site with additional landscape fabric; rope lines with caution-tape flagging also added to bolster dissuasion of terns nesting outside the 2-acre tern colony area on East Sand Island; we thank Paul Schmidt (USACE), Vanessa Loverti (USACE), Blaine Parker (CRITFC), Dale McCollough (CRITFC), Jenny Hoskins (USFWS), and Geoff Dorsey for assistance in reinforcing nest dissuasion fences on East Sand Island
4/15/11 ›
High count of 28 double-crested cormorants in cormorant nest dissuasion area on East Sand Island; no nest initiation or breeding behaviors observed
4/12/11 ›
PIT tags sown for smolt PIT tag detection efficiency study on East Sand Island Brandt’s cormorant colony
4/11/11 ›
PIT tags sown for smolt PIT tag detection efficiency study on East Sand Island double-crested cormorant colony
4/11/11 ›
Commenced feasibility study on efficacy of flagging tape to dissuade double-crested cormorants from nesting in trees on East Sand Island
4/11/11 ›
Colony monitors began continuous monitoring of East Sand Island Caspian tern and double-crested cormorant colonies
4/11/11 ›
First double-crested cormorants (~ 1,200) observed on East Sand Island colony; first Brandt’s cormorant (1) observed on East Sand Island cormorant colony
Weekly Update for 4/4 – 4/10/2011
4/4 – 4/10/11 ›
Signs of multiple predators observed on East Sand Island; bald eagles and peregrine falcons have been observed at both ends of the island; at least one common raven was a regular presence near the tern colony area; fresh river otter and raccoon tracks observed on island
4/8/11 ›
Nesting dissuasion fences erected adjacent to the East Sand tern colony site reinforced with plastic hardware cloth along the bottom edge to prevent fences from ripping and flapping in the wind
4/7/11 ›
Hundreds of Brandt’s cormorants observed roosting on pile dikes adjacent to East Sand Island; hundreds of double-crested cormorants observed on the water north of East Sand Island; to date neither species of cormorant has been observed on the island itself
4/7/11 ›
Equipment used in colony site preparations removed from East Sand Island; we thank Dave Nichols and Jim Neva with the Port of Ilwaco for use of their barge and help in transporting equipment and supplies to and from the island
4/6/11 ›
PIT tags sown for smolt PIT tag detection efficiency study on East Sand Island tern colony
4/5/11 ›
USACE contractor (Bear Power) completed construction of visual barrier fence measuring 60 yards long and 8 feet tall on the east end of the East Sand Island double-crested cormorant colony; this pilot study is to set up an eastern boundary to the cormorant colony that would exclude ca. 15% of the colony area used by nesting cormorants in 2010; if cormorants start to build nests on the east side of the fence they will he hazed prior it egg-laying; radio telemetry techniques will be used to monitor whether hazed individuals relocate to undisturbed areas of East Sand Island to re-nest, leave East Sand Island to re-nest, or fail to re-nest
4/5/11 ›
First Caspian terns (85) observed on East Sand Island tern colony
4/5/11 ›
Completed construction of blinds and tunnels at East Sand Island double-crested cormorant colony; completed preparations for monitoring double-crested cormorant colony on East Sand Island
4/4/11 ›
Nest dissuasion fences erected around the East Sand tern colony site to limit the available tern nesting habitat to 2 acres; completed preparations for monitoring Caspian tern colony on East Sand Island
Weekly Update for 3/28 – 4/3/2011
3/31/11 ›
Completed construction of observation blinds and laid out colony grid at East Sand Island tern colony
Weekly Update FOR 3/21 - 3/27/2011
3/24/11 ›
2-acre area staked out on East Sand Island for Caspian tern colony site preparation adjusted to avoid flooded habitat at east end of the colony site and include more suitable habitat further west; 2 acres of suitable bare sand habitat prepared for nesting Caspian terns on East Sand Island colony site by USACE
Weekly Update FOR 3/14 - 3/20/2011
3/18/11 ›
First Caspian tern sighted in Columbia River estuary by project staff in 2011; 1 Caspian tern observed flying near East Sand Island
3/18/11 ›
2 acres staked out on East Sand Island Caspian tern colony site in preparation for restoration of 2 acres of tern nesting habitat prior to the 2011 nesting season
3/14/11 ›
Seasonal field crew began work in Columbia River estuary
