Birding Washington County, Oregon

Bald Eagle Diary: 2002

Dennis Manzer posted the following messages concerning Bald Eagles nesting at Jackson Bottom Wetlands, Hillsboro, to the on-line discussion group, Oregon Birder's On-Line (OBOL).


Monday, January 21, 2002

Hi all,
Jackson Bottom had 5 TREE SWALLOW on 01/19/02, 3 TRSW & 2 BARN SWALLOW on 01/20. Other notables were 5 subadult BALD EAGLE (mixed age classes, 2yr thru 4yr) on 1/19 in addition to the resident pair of adults. 1 NORTHERN HARRIER, 2 AMERICAN KESTREL, 5 RED-TAILED HAWK, 1 PEREGRINE FALCON. 1/20 the RED-SHOULDERED HAWK made itself visible much of the afternoon.
Yours for better birding,
Dennis (:>}


Friday, February 1, 2002

Greetings!
The RED-SHOULDERED HAWK is still being seen today, 02/01/02, as the latest high water event recedes. At any given time from 2 to 7 RED-TAILED HAWKS may be seen. On 01/26 there were 1 imm BALD EAGLE, 2 adults, 1 PEREGRINE FALCON, 1 NORTHERN HARRIER, 1 AMERICAN KESTREL, BUSHTITS, BLACK-CAPPED CHICKADEE, & RUBY-CROWNED KINGLET in & out during the course of the day.
On 01/19 there were 5 subadult BALD EAGLES representing all age classes in addition to the resident pair of adults. On 01/31 there was a 3rd adult perched a short distance from the residents. They eyed each other more than 40 min. before finally engaging in an airshow & disappearing behind the treeline bordering the retention pond just as dusk turned to dark.
For those of you who haven't visited in a while, the eagles have begun a new nest much more visible than the old one. The original blew out on the night of 11/30/01 during an all night gale of 40 mph sustained wind with gusts to 50 mph. I laid awake all night listening to it howl & all the while fearing the worst.
Well, I think it turned out to be a lucky break after all, as this new nest has been placed within the existing nest grove, but at its Southwest margin. The nest is being built upon a very horizontal limb of an oak right at its juncture with the trunk. The eagles had returned in early Oct. & had been adding sticks to the original nest on a daily basis. It was located in a young, limber Oregon Ash. After the blowout they ceased gathering sticks & I feared they may build in a different neighborhood altogether. But on 12/10 they each brought sticks to their nest grove.
Each brought a stick to a different spot & placed it. Then the other examined the placement of the stick by its mate. Next, one of them brought a stick to the present spot & the building commenced. They've been adding to it steadily since then & it's about 3'~4' tall X about 6'~7' wide. Some of the sticks they've used are about 7' long & several have multiple forks. At no time have I witnessed plundering of the remains of the old nest, and in fact have only once seen one of the eagles atop it. They've also added reed canary grass, mud, & sod. Tonight for the first time I observed them each taking multiple turns lowering themselves into the nest as if "trying it on" and making desired adjustments to its interior. They were still perched above it when I left @ 5:52 p.m.
Other passerines seen this past week include SPOTTED TOWHEE, DARK-EYED JUNCO (OR), FOX SPARROW, LINCOLN'S SPARROW, GOLDEN-CROWNED SPARROW, SONG SPARROW, HOUSE SPARROW, HOUSE FINCH, AMERICAN ROBIN, RED-WINGED BLACKBIRD, STARLING, WESTERN SCRUB JAY, YELLOW-RUMPED WARBLER, 10 TREE SWALLOW, 3 BARN SWALLOW, BELTED KINGFISHER, BAND-TAILED PIGEON, ROCK DOVE, MOURNING DOVE & 1 BEWICK'S WREN. The dramatically fluctuating water levels really affect the presence &/or absence of waterfowl. The most common remain RING-NECKED DUCK, NORTHERN PINTAIL, MALLARD & DOUBLE-CRESTED CORMORANT. AMERICAN WIGEON, PIED-BILLED GREBE, AMERICAN COOT, LESSER CANADA GOOSE, GREATER CANADA GOOSE & COMMON MERGANSER are usually present. Only occasionally GREEN-WINGED TEAL & CINNAMON TEAL. The TUNDRA SWAN are in & out but down from their peak of 600 during the prior high water events. Jackson Bottom Wetlands Preserve can be found in DeLorme Oregon Atlas p66, D1. The N view stand is located approx 1/2 mi S of downtown Hillsboro, OR, on OR Hwy 219 (S 1st St.).
Yours for better birding!
Dennis (:>}


Sunday, March 3, 2002

Obol,
Happy 9th anniversary! Today @ about 1630 a strange goose came in for a landing with a sizable flock of CANADA GEESE, mixed greaters & lessers. As it descended at first glance I thought it was a Greater White Fronted but something just wasn't quite right. I quickly laid the scope on it to discover no white front. Uh-oh...study this bird for marks, colors, & shadings.
A lady got out her NGII & I my NGIII. We took turns calling out descriptors & were able to eliminate several possibilities. Finally I got out my Sibley & bingo, there it was as if the live bird in front of us had been painted by the very artist himself! Neat treat!!
The BALD EAGLE pair hasn't begun incubation yet. There was a 3rd adult in the vicinity on Sat and a 2 yr most of Sun. Possibly the fledgling of 2000. The adults tolerated its presence at a measured distance as they allowed it to fish & feed unmolested.
Jackson Bottom Wetlands Preserve is located approx 1/2 mi S of downtown Hillsboro on S 1st St, (OR Hwy 219).
Yours for better birding!
Dennis (:>}


Monday, April 8, 2002

Greetings!
Among the more interesting things this evening were 17 TUNDRA SWAN, 12 of which had clear white necks. 5 had only a slight hint of gray. All bobbed their heads rhythmically as they leisurely swam about before departing at 1955 hrs. They circled the N end 7 times to slowly gain altitude before heading E above TV Hwy for some distance before veering N toward the Sauvie Island direction.
Other notables were a pair of CINNAMON TEAL in spring finery, very vocal GREATER YELLOWLEGS, & yet 2 GREAT EGRET.
This is incubation day 32 for the BALD EAGLES. The hatch is imminent. My betting cash goes for Fri, 04/12/02.
Jackson Bottom Wetlands Preserve is located approx 1/2 mi. S of downtown Hillsboro, OR, adjacent to OR Hwy 219 (S 1st St.). Consult DeLorme Atlas p 66, D1.
Yours for better birding!
Dennis (:>}


Sunday, April 14, 2002

Greetings!
At least one eaglet hatched on Fri, 04/12/02. I observed 4 feeding sessions between 1620-1940 hrs. Duration varied from 7 to 12 min. The prey item was large but unidentifiable and was already in the nest prior to my arrival.
Saturday's feeding sessions averaged 3-7 min duration approximately every 50 minutes. Sunday's sessions were lenghtier & more frequent. This may suggest more than one chick. With any luck the eaglets should be scope-visible from the N viewing stand within a week since the nest location gives such a clean sightline.
A Sunday highlight was when the M BAEA captured a large carp from shallow water. The eagle struggled crazily to gain altitude with his unweildy cargo. The apparent ineptness prompted a lot of questions from onlookers & puzzlement on my own behalf, when a blur of a PEREGRINE FALCON blitzed the eagle from out of nowhere. It tried twice to seize the eagle's prize but was met with adroit maneuvers & flips by the eagle which then replenished the nest pantry.
Yours for better birding!
Dennis (:>}


Sunday, April 21, 2002

Greetings!
There was a lot of action @ the ol' bottom today. The eaglets hatched on 04/12 & 04/14 as expected. There are 2 & that seems to be all. This should be a very interesting experience. Both adults are great providers. At no time during the past 8 days (49 hrs observation) were the adults forced to hunt to fulfill an immediate feeding demand from the eaglets. Feedings are every 40 - 60 min for as little as 3 min all the way to 25 min. Both eaglets are scope-visible from the sidewalk at the N parking lot during most feedings.
Up until later this afternoon both adults seemed to be great defenders of their territory as well. There were visits from an adult F, adult M (twice), 4 1/2 yr F (wearing a beautiful sub-terminal band on her tail), 1 nearly 5 yr M (smudgy gray in the head & rectrices) and a PEREGRINE FALCON all before 1400 hrs. Each was vigorously escorted out of the area, sometimes by both adults or sometimes by only one.
At 1500 hrs the nearly 5 yr M returned bent on destruction & amour. The pair chased him quickly to the distant S & out of view. The F returned to her nestlings. About 30 min later the rascal returned & raided last year's nest. The resident M was lurking on the E side of the nest grove & rose to chase when the F joined in. She went only a short distance before returning. The M continued pursuit out toward Meriwether Golf Course & out of view.
Another hour passed & the interloper returned making a stoop on the nest which he averted at the very last moment. The resident M again appeared from nowhere to give chase to the S while engaging the intruder 3 times midair. A fine aerobatic display! They both went out of view.
At 1900 hrs the dirty bugger came back & perched ~8m directly above the nested F. She began screaming & crying her loudest & longest. She was clearly audible across the 400m. Her mate was not to be seen. After about 15 min of this the interloper aggressively dropped straight down ~2m. The F became even more hysterical & still no sign of her mate as the terrorist gazed down upon her nest of young. Periodically my wife, Diane, our daughter, Michelle, & I thought we heard a weak distress answer. None of us could quite pinpoint the location of the suspected call. Locations seemed to vary & responses were very irregular. I began to fear the worst, perhaps that there had been a fight & our dad bird got whupped.
I grabbed 1 of the scopes & drove to the Water Quality Lab parking lot 0.7 mi S for a different perspective. Nothing. Scoped everything I could think of as a possible retreat.
Her screaming continued until 2040 hrs when her mate finally appeared from the near darkness. He came in with a contact call, she continued with a distress call. We quickly lost track of him as we were keeping all eyes on the nest. The terrorist began to fidget as both he & our mom eagle cast their gazes toward the general direction of the M.
Suddenly the unwanted company made a break for it to the east & the F just as suddenly gave chase but wisely made a U-turn to her nest. I could see flashes of white of 2 bald eagles thru the trees as the 2 M's clashed. By then it was too dark to follow any further events, but as I left the F was in her nest.
I've never thought I could harbor the thought of never wanting to see an eagle again - but this aggressive youngster is more welcome as a memory than as another day-guest. This was one terrifying day.
Yours for better birding!
Dennis (:>}


Monday, April 22, 2002

Greetings!
After Saturday's terror at Jackson Bottom, I thought it prudent to begin there today, Sun. Both adults were present upon my arrival @ 0620 & seemingly healthy. Both eaglets fed heartily @ 0700. Feedings continued about hourly as usual the preceding week. All seemed to be normal. Best bird of the visit had to be HAIRY WOODPECKER up close.
Fernhill was next on the route. Both of the nearly 5 week old eaglets were exercising & lazing atop their aerie as mom stood by. Both looked healthy. No other eagles were seen. Prettiest sight was a mixed group of single sparrows side by side upon a single branch: LINCOLN'S, SONG, GOLDEN CROWNED, WHITE CROWNED. Other interesting birds were a single CANVASBACK on Eagle Perch Pond, ~60 DUNLIN, 4 WESTERN SANDPIPERS, 8 LEAST SANDPIPERS, 3 DOWITCHERS, & 2 GREATER YELLOWLEGS in standing water across Fern Hill Rd on its W side.
My 2 hour visit to the Hagg Lake BALD EAGLE nest site proved inconclusive beyond the fact that the nest is occupied. The M was perched ~150m E of their aerie. The F was in the nest but all I could see was <1/2 of her beak & ~3/4" of 3 rectrices. A very tough sight line. She did make some movement which could be broadly interpreted to suggest a possible nestling. (Lotsa wiggle words in that sentence!) Their hatch date was forecast for 04/20, so I'll be keeping an eye out for prey deliveries &/or stand-up tending. It's a really tough sightline in, around, & through dense foliage with only a couple of peepholes & exactly 0.5 mi distant. What a joy (;>)! Best birds today were 3 squabbling RED-BREASTED SAPSUCKERS up close in a brief moment of bright light.
I spent the last 6 hours of daylight @ Jackson Bottom where all was peaceful, the eagles strong, & the feedings were above average. Still pretty well convinced of only 2 eaglets.
Yours for better birding!
Dennis


Saturday, May 11, 2002

Greetings!
Today, Sat, 05/11/02, was NAMC. I posted to Jackson Bottom Wetlands Preserve's N viewing stand @ 0519 thru 2055 hrs. All observations were made from this location. I travelled 17 mi round trip from home & no birding was done while driving. I took a 30 min break after 5 hours & a 20 min break after 10 hrs but continued vigilance throughout. Visitor distraction was minimal.
I normally monitor the nesting Bald Eagles at this site. The chicks are 4 weeks old now & getting 2nd down. Today I witnessed for the first time this season the adults being forced to hunt to satisfy a feeding demand. They failed 2 demands. Apparently their pantry has gone bare & I hope only a temporary condition. The F did make a small prey capture @ 2045 so the eaglets entered darkness with at least a little something in their stomachs.
The N view stand is located approx 0.5 mi S of downtown Hillsboro, OR, on Hwy 219 (S 1st St). See birdnotes.net "Site Guide" section for additional info.
Yours for better birding!
Dennis (:>}


Saturday, May 25, 2002

Greetings!
A single BLACK TERN was working the distant water in front of the N viewing stand on Fri from 1600 - 1900 hrs. This is my first sighting of this specie this year. In '00 &'01 they visited in mid April, mid May & late May. I was beginning to wonder if maybe we'd been dropped from their itinerary.
Other fun birds being seen regularly include CEDAR WAXWING, BELTED KINGFISHER, GREEN HERON, & SPOTTED SANDPIPER. The SPSA act as if they're interested in nesting again. Many of the KILLDEER are on second clutches. CANADA GOOSE families are paddling about & broods range from 6 wks to 1 wk. There has been very little eagle depredation on the waterfowl this spring. Several of the earliest broods are still intact.
The BALD EAGLE family is thriving. Their diet is >95% carp. The eaglet twins are 6 weeks old now & exercising vigorously, sometimes even getting daylight beneath their talons as they beat their wings furiously. They have exhibited almost no sibling rivalry from the hatch & each continues to be fed more or less equally.
Jackson Bottom Wetlands Preserve is located approx 0.5 mi S of TV Hwy (OR Hwy 8) from downtown Hillsboro, Or, on OR Hwy 219 (S 1st St). See birdnotes.net for additional details in their "Site Guide" option.
Yours for better birding!
Dennis (:>}


Saturday, May 25, 2002

Greetings!
One eaglet 6 weeks old shredded prey in the nest & offered same to its sibling. The sibling accepted about 10 offerings in this fashion. Neither parent was in the nest at the time but each was nearby. I've never witnessed this behavior before & wonder if anyone else has? Any responses kindly appreciated. Thanks in advance.
Yours for better birding!
Dennis (:>}


Tuesday, July 2, 2002

OBOL,
Loud firecrackers were being exploded today some several blocks away from the BALD EAGLE family of Jackson Bottom Wetlands Preserve. The adults about got whiplash with each report. The juv's didn't seem to notice. These crackers weren't M-80's or anything near their size but the pops got my attention over the normally high ambient noise. What's really peculiar to me is that during the waterfowl hunting season, the skybusting sportsmen across the highway pop off with their 10 & 12 gauge shotguns & the eagles don't even twitch. I think the birds' reactions are related to the sharpness of the "boom". Even small firecrackers have a sharper report than the shotguns. Another influencing factor could be that during the winter the eagles are only occupying territory & aren't brooding young or overseeing fledglings on the wing.
Yours for better birding!
Dennis (:>}


Tuesday, July 2, 2002

Greetings!
The BALD EAGLE fledglings (suspect both M) are successfully in the air. They took wing on 06/28 & 06/30, each at exactly 11 weeks uncannily almost to the hour. They are quite a sight in flight! A little shaky here & there but they have their share of graceful successes as well. The landings can sometimes be real heart stoppers. This (07/02) evening's 1730 breezes with gusts to 15 mph brought them off of their hidden perches & into the sky for some real airshow demo's of their abilities. They played in the air together & sometimes flew formation as they continued to discover their newly acquired powers.
They return to their eyrie to feed at will & so far the parents have had a full pantry waiting. This evening I saw the adult F take a 5~6 lb carp but rather than delivering it she simply put it aside, presumably for consumption at a later time.
One of the young was perched on a fairly visible branch in the N of the nest grove for quite some time which I hadn't previously noted as ever being used. Its mother was perched about 10m higher & a little further N. Then the adult M came from seemingly nowhere & moved it off the perch. The juv hastily departed to the S end of the grove & had 2 missed attempts to perch atop the last tree on the right which is a clear shot. Oddly he continued on into the thicker trees just meters from last year's nest & landed after a fashion with a lot of imbalance & counterbalancing wing-flapping. At least the indignity of it all was somewhat obscured by the heavier foliage.
They seem to be most active at the first hour of daylight & then tapering off by 0800 or so. They again become active between 0930 & 1000 when the thermals begin to develop. Hot afternoons are for shady siestas. They get active again as the temp cools & the late afternoon/early evening breezes pick up. Best photo light is after 1600 hours. Bring a gallon of patience.
Yours for better birding!
Dennis (:>}


Tuesday, Octctober 1, 2002

Greetings,
This p.m. @1655 PDT a MERLIN sliced through the N end. I had already thoroughly glassed and found nothing different but glassed again & there was an adult male BALD EAGLE perched atop the southernmost snag in the nest grove.
It made 2 position changes in 40 min. Once to the NE corner of dead cottonwood & then to the favored perch in the N end of the nest grove. It investigated the available waterfowl which went berserk on each position change, but made no strikes.
Other birds present & not seen previously this week included 2 BARN SWALLOW, 30 BUSHTIT, 1 AMERICAN KESTREL, 40 VAUX'S SWIFT & 3 NORTHERN FLICKER.
Jackson Bottom is located approximately 0.5 mi S of downtown Hillsboro, OR on the E side of OR Hwy 219 (S 1st St).
Yours for better birding!
Dennis (:>}


Friday, October 18, 2002

Greetings,
The female of the pair joined the male in residence on the p.m. of TUE, 10/15. They act like the same pair of the most recent nesting season. I've not seen any activity on or near the nest however it's way early for any stick gathering just yet.
This evening's highlights included an adult PEREGRINE FALCON on premises as well. 2 LINCOLN'S SPARROW were just off the N view stand. 1 WILSON'S SNIPE was on the long island in front of the eagles' nest grove. Aprox 5K CANADA GEESE, mostly Cacklers, settled in just after dark. Yesterday I saw two with yellow plastic collars but too distant to glean markings. BELTED KINGFISHER is still regular as are 3 - 5 GREAT EGRET. GADWALL are coming into beautiful plumage.
Jackson Bottom Wetlands Preserve is located approx 0.5 mi S of downtown Hillsboro, OR, on OR Hwy 219 ( S 1st St).
Yours for better birding!
Dennis (:>}


Monday, October 21, 2002

Greetings!
Last week upon the arrival of the F BAEA I mentioned in my post that I thought it was way too early for stick-gathering & presentation at the nest. Well, that may have been true last week but it's under way now. The M broke off a fairly green stick approx 4.5' length & multi-forked of unidentified tree sp & delivered it to his mate upon their nest.
If any of you observers out there see similar BAEA behavior, I'd certainly appreciate an e-mail noting the circumstances & approximate location to "Dennis Manzer". Thanks in advance!
Yours for better birding!
Dennis (:>}