Baltimore Oriole Project 2012 (updated)

Baltimore Oriole Hotspots at the CRP
I've been casually recording Baltimore Oriole songs at the Charles River Peninsula in Needham, MA over the last four years. This year I've decided to do things a little more systematically so I've been out on consecutive days trying to get a fix on things like individual singers, territories, and nesting spots. I am not a trained birdsong methodologist nor do I use a parabolic microphone (as important as binoculars for serious practitioners of birdsong research) but I am learning a great deal. Including how difficult it is to get a fix on individual singers, territories, and nesting spots.

This research hinges on the fact that Baltimore orioles have unique songs that makes them identifiable as individuals. The truth, as I've found out, is a little trickier. Baltimore orioles usually have unique songs but they can also learn the songs of neighboring birds. Also, female Baltimore orioles also sing and will sometimes incorporate fragments of their mate's songs. And Baltimore oriole males like to sing in fragments so sometimes its hard to know what their full song is.

I've provided a map of oriole hotspots above. Over the past 4 years I've heard unique songs consistently at these locations. Some of these cluster: zones 1, 2, 3, and 12 tend to overlap, creating regular conflict between males (and females); the same is true of 5, 6, and 7. Orchard orioles also abound at the Charles River Peninsula. I won't be logging my observations of them but you can see them regularly at multiple locations (this year 1, 3, 5, 9 especially).

This page is organized chronologically but some observations are interpreted retrospectively. I use soundcloud to embed the songs, which has its pros and cons. Sometimes all the widgets won't load and after one play you get a "share" window that you have to click out of in order to hear the song again.

Now that the project is largely complete, I've assigned letters to each of the oriole songs I've identified. (I managed to use the whole alphabet). Some songs were only heard once, others just in fragments, and some may just be variations of other songs. Please feel free to let me know if you think I've misidentified something. 

 May 4, 2012. Afternoon walk at Charles River Peninsula

The Baltimore Orioles have been back for two days. I finally get my act together, put batteries in my trusty Edirol R09, and head out in the afternoon expecting great things. Only one oriole is singing full songs and it's a familiar one, heard the last two years at this location--the Redwing Bay parking lot (Zone 1 above).  I will call this Oriole A. Here it is:

The sonogram for this song looks like this:
(The dark lines map the melody. The faint lines above are overtones. )

 May 5, 2012. Early morning at Charles River Peninsula

An earlier start. I arrive at the CRP by 6 a.m.  It was supposed to rain but it's not raining yet. Two new Baltimore oriole songs, one by the riverside (zone 3 above). I will call this Oriole G. (In retrospect it would appear that this is not a full song but a string of fragments.)

 Down by the point of the peninsula (zone 6), the site of many fierce oriole conflicts in the past, I hear a clear oriole vocalization. It sounds fragmentary but may very well be a full song. I will call it Oriole U:

May 6, 2012. Early morning at Charles River Peninsula

At the CRP by 6 again. A wheezy blue-winged warbler is presiding over the soundscape. This time I was going to get serious about recording orioles and despite the distraction of bobolinks I was able to capture some good songs. This was a day of conflict. Three separate incidents (two recorded) involving three or more orioles at different spots on the property.

Let's start with a brief exchange at the CRP entrance (zone 3 on the map above).


The first song I'll call Oriole H. (I never heard it again). The second sounds like Oriole A but it is actually one of two orioles singing approximately the same song. I'm going to call it Oriole A/B because I'm not sure which one of the two it is.

Moving down to the point of the peninsula (zone 6) I hear two distinctly different songs. The first, which I've labeled Oriole K, goes like this:


The second, which I've label Oriole Q, goes like this:


These two birds (joined by others) were going at it. Here is an extended recording of their conflict, with Oriole U and Oriole K exchanging songs (I think Oriole K won). (Note: there are rose-breasted grosbeak and catbird songs in there as well)

Then later, from zone 8 on the map, I heard Oriole K and Oriole K singing in a kind of overlapping conversation (Oriole U is in there at least once as well). 

I also discovered a third oriole song down the wooded path from the point (zone 8 on the map). Could this be Oriole G?


Finally, another major conflict down by the railroad tracks (zone 9 on the map). Two voices are clear. The first song is from a male presiding over the area. We'll call him Oriole X.


The second song, a highly unusual, even comic song, is our first female song (Oriole Y). I had a hard time believing it was really an oriole until I saw her singing it.


Here is an extended recording of the voices in conversation. It sounds like a conflict. About half way in a second male oriole (Oriole Z) can be heard and Oriole X drops out.

May 6, 2012: Evening stroll around Cutler Pond.

I had such success in the morning recording orioles that I couldn't wait to go out again and record some more. Out to Cutler Park to record orioles on a circuit around the pond. I've had much better luck in the past. This evening the orioles were singing in fragments if at all. And I always forget how much traffic noise there is (not a good place for recording in general). Nevertheless, I did get one to voice its lovely song:

May 7, 2012: Afternoon walk at Charles River Peninsula.

I rush to the Charles River Peninsula after work, recorder in hand. It is a beautiful afternoon. I see discarded shoes on the grassy path up to the shagbark hickory hill. A women is playing with her three toy dogs under the tree.

A new Baltimore oriole song (Oriole R) in the woods by the river (zone 3).


I walk down to the point (zone 6). It is quiet. But as soon as I enter the woods (zone 7) I hear something interesting.


This is a female (Oriole F). It is actively involved with other orioles (Oriole K and Oriole Q) in the area, as this snippet from a longer exchange indicates.

Finally, down to the traintracks (zone 9). Here is another new one, presiding over the scene.

Or is it a new one? Compare the sonograms of this one

and Oriole R at zone 3.

It would appear that zone 3 repeats fragments of a song sung more fully at zone 9. Could it be the same bird at a different location?

May 8, 2012. Mid-morning walk at Charles River Peninsula.

Tuesday morning, after bus stop duty, I headed out to the CRP. This day the intention was not birding but research. I decided to change my method. Rather than recording and then figuring out where I was and who was there, I added notation verbally to the recording itself.

It is overcast but not raining. I start at the parking lot (zone 1). There is a lot of construction noise from the bridge project down the river. I immediately see two different male-female pairs. Two distinct songs at the parking lot plus one (unrecorded) across the river. I'm pretty sure this is one of the females (Oriole C).

And then a song I'll call Oriole D but could very well be a fragment.

I walk down to the entrance. It is beginning to rain a little. From the train tracks (zone 12) I hear a rather interesting Baltimore oriole song (Oriole E). Here is a snippet:

I can't get a clean sonogram because of that very loud song sparrow but this is one we'll hear again more clearly.

A walk through the woods (zone 3) reveals Oriole R in the same location as previously. I keep walking down to the point (zone 6). Things are initially quiet so I walk a little ways into wooded path (zone 7). The female (Oriole F) and one of the male voices (Oriole Q) from previous recordings are conversing. Turns out my earlier recording of the male was incomplete. Here's a fuller version:


I stand for a bit recording while watching orioles fly back and forth between the woods and the point. A magnolia warbler flits nearby and every once in a while a northern waterthrush pops up out of the brush and sings.

It is getting windy but I can still make out Oriole X and Oriole Y down by the traintracks (zone 9). Completing the loop Oriole E in zone 12 is still presiding and Oriole R in the woods (zone 3) continues to sing in repeating fragments.

May 9, 2012. A rainy morning walk at Charles River Peninsula.

Down at the parking lot, warbling vireos provide the action, chasing each other around. Warbling at each other.

Two male orioles show themselves. One sings in familiar fragments (Oriole A/B). A gorgeous female appears, pulling fibers for nesting material off the some vines. She flies on into the brush without singing.

I walk down the path (zone 2) to the CRP entrance. The female from yesterday (Oriole C) unleashes a few choruses of her song. While I'm waiting, listening for more, an osprey flies by down the river, pursued by red-winged blackbirds. I notice another female and male near the hill at the top of the parking lot.

The overall birdsong is intense--between continuous choruses of rose-breasted grosbeak and catbird chaos I'm now hearing the male (Oriole E) that I heard the previous day at zone 12. He is now advertising in zone 2.


He sings and sings in the tall oaks lining the path. After a bit he starts vocalizing entirely in one and two note fragments so I move on.

On the way down to the point past zones 3 and 4 (today devoid of Baltimore oriole song),  I find half a dozen bobolinks, including one female, singing in the trees lining the river. I walk out to the end of the lookout (zone 5) and listen. A familiar voice from the edge of the river. It is Oriole G singing from another position--then another unfamiliar voice overlaps.

Alas, the second voice isn't heard again.

As I arrive at the point (zone 6), I am greeted with a growl.

A male/female pair. She has nesting material. And there's another male/female pair. And a third male. They are not getting along. Here's an excerpt, with fragments of one unidentified song and the female, Oriole F.

Later, another exchange between males, Oriole Q and a new one, Oriole M, this time overlapping a grosbeak song.

After more listening it would appear that the territory of Oriole M shades toward the path (zone 7) while Oriole Q shades toward the point (zone 6). Then they meet in the middle and fight.

Here's Oriole M again, in conversation with a female (Oriole W), it would appear.

I walk down to the train tracks (zone 9). Familiar voices, male (Oriole X) and female (Oriole Y). As I approach the entrance (zone 12), I hear a fragmentary song that could be Oriole A/B or someone different.


And then I spot a different male pursuing a female into the woods at the riverside (zone 3). I don't hear him but I do hear her (Oriole S).


She's assembling fibers on a branch over the river, just across from nesting box 2. Could this be our first nest?

As I walk back to the parking lot along the path (zone 2) I hear the male from earlier in the morning (Oriole E) continuing his concert. Full songs one after another.

It is now raining hard. Time to leave. Back tomorrow.

May 10, 2012. A very rainy quick walk through the Charles River Peninsula

Not much action in the parking lot.  As I walk down the entrance path I am delighted to hear a blue-winged warbler. Is it the same one as last week? The male oriole from the previous day (Oriole E) continues to advertise in the tall oaks (zone 2).

It is raining very hard so I quickly make my way down to the point (zone 6). I hear the same male and female voices as the previous day. Have things started to stabilize?

Not so fast. A commotion. Two males (Oriole M and Oriole Q--there's also a hint of Oriole F) go beak to beak.

I stand around for a while, getting good looks at the females, who will occasionally go to the ground. There is a yellow-throated vireo singing vigorously in the woods. He is not our resident male, displaying much more musical talent.

As I move down the path, I notice a female on a branch above the river. A mat of fibers is waving like a pennant in the wind. Our second nest!

Quick work around the rest of the peninsula and I'm back on the entrance listening to Oriole E sing repeatedly from the tree tops. I hope the weather will be better tomorrow.

May 11, 2012. A windy morning walk through the Charles River Peninsula

It is a bright and sunny day. Good for photographs but bad for recording. The wind has picked up and the construction crew fixing the South/Willow Street Bridge is hard at work with heavy machinery.

I immediately confirm what I had been suspecting. Two orioles (Oriole A and Oriole B) are singing the same song. One across the river and one in the woods near the parking lot. They follow each other below.

The sonogram might be a way of seeing if they are truly identical or not.

Compare the fourth note between the songs. It has a slightly different shape. This is something worth investigating more fully....
Oriole A
The male (Oriole E) advertising in the oaks over the entrance path is now singing from the other side of the river. He is flying back and forth across the river and interacting with Oriole B.

Down by box four (zone 4) a female oriole is pulling fibers from vines. I hear her simple four-note song (unrecorded).

Recording is difficult at the point (zone 6) because of wind and catbirds. And the overall level of song has declined. I do manage a couple of photos. One of those pictured sings the dominant (for the moment) path song,
Oriole M
the other, which I've used for the generic oriole image on my soundcloud tracks, is an unidentified songster.

 I also get an unidentified female.

The male at the top is likely (though not positively) associated with the nest, now just about completed.

Down at the train tracks, I see a male (Oriole V). I catch some fragments.

It would appear that the oak grove extending into the meadow (zone 11)  is now being used by Baltimore orioles, though I was unable to get a recording. On my way out, I notice males chasing each other in the trees above the path (zone 3). Could these be the two (Oriole A and Oriole B) conversing across the river earlier?

May 12, 2012. An early morning walk at the Charles River Peninsula.

A quiet morning at the CRP. I immediately hear two familiar songs, one coming from across the river (Oriole B), the other from the entrance path (Oriole E).

A quiet morning, except perhaps for catbirds and Canada geese...Quiet enough to hear a nice warbler group in the trees above the path.

Down by the point (zone 6) the orioles are being very quiet. I catch some oriole song from across the river. Then I see the male and female pair close to the nest. They sing a tiny bit (mostly growl).

I try and succeed to track down a Wilson's warbler (the same as last week?) in the brush. And I hear a familiar song (Oriole G) that I hadn't heard recently from the path (zone 7)

Down by the train tracks I see two males (Oriole V and Oriole X) in chase mode. The female with the funny song (Oriole Y) is still there. Here's a snippet where you can hear all three (the last distant one is the loser).

May 12, 2012. A short afternoon visit to Hemlock Gorge.

After dropping my daughter off at a birthday party, I wandered over to Hemlock Gorge. There was northern parula (unseen) from the tree-tops. And a Baltimore oriole singing (seen).

Here's its lovely song.

May 13, 2012. A very productive early morning walk at the Charles River Peninsula.

Another quiet early morning at the CRP. I immediately hear sings from Oriole A, Oriole B and Oriole E. Ah, stability....

Guess again. After a few choruses of the path song, suddenly a new voice. Could that be Oriole F, the female from down at the point?

Then Oriole A flies in.

Then we have an amazing sequence with four different oriole voices (Oriole E, Oriole F, Oriole C, and Oriole A) in conversation, five if we include distant Oriole B from across the river.

This seems to have been triggered by a female in full "mate with me" display mode. Since this was happening in the tall oaks (zone 2) I assumed it would be the most prominent singer in the zone who would take the lead. Wrong. It was Oriole A. Oriole E was content to just keep on singing.

Down to the entrance, there is a male and a female oriole in the aspens, a favorite nesting spot in past years. They are silent.

I hear vigorous singing up ahead, around nesting box 4 (zone 4). It is Oriole G in yet another location, singing over and over, with relatively short pauses.

He moves down to the riverside. The intensity seems motivated by something. I hear growling and a short burst of song from Oriole F.  (Wasn't she just up by the parking lot?)

There are three other male orioles in the area (unsinging). They move away and he eventually stops singing.

The point and the wooded path are quiet of oriole sounds. Down to the train tracks, where Oriole V is presiding over the scene. He is singing continuously, but not very loudly (the blue-winged warbler, cardinal, and yellow-throated vireo are all louder on the recording).

I hear another song up ahead in the oak grove (zone 11). Is it really an oriole? Sounds like a titmouse.

I doubt this is his full song but it's what he keeps singing. He moves into the trees at the gate to the Walker School (zone 10). A male and female immediately chase him off. I leave him singing his plain song from the branches of the hilltop hickory.
"Titmouse," partially obscured.

May 14, 2012. A rainy afternoon walk around the Charles River Peninsula.

I make it down to the CRP after work. It is raining but I expect it to break so I put on my raincoat and rubber boots and head out. The rain comes down in torrents. For about twenty minutes. I stand under a tree in the woods by the river (zone 3) watching and listening. I hear an interesting female (Oriole T) before I decide to move on.

Down at the point there is a brand new singer (Oriole O--never heard again), singing continuously.

Every once in a while the old timers get a line in. But they are mostly busy drying themselves off.

The rain lets up and I walk down to the train tracks. I hear this curiously familiar yet utterly wrong phrase.

It's a catbird, also picking up oriole song fragments. The real oriole, Oriole V,  is still singing continuously, aggressively fighting off an opponent.

Back at the parking lot, Oriole A and Oriole C. It begins to rain hard again, but I'm glad I took the chance and came out today. I'll dry off at home.

May 15, 2012. A drier morning walk around the Charles River Peninsula.

I arrive at the CRP a little later in the morning than I'm used to. The parking lot is filled with trucks, associated, I think, with bridge-building work. A few fishing boats too, on this non-rainy morning.

I'm immediately confused by the dominant oriole song at the parking lot.

That's a familiar song. But it's not Oriole A! The singer sings continuously. It's Oriole G, the traveling salesman, apparently unable to make a connection yet.

Down around zone 4, down near box 5, I hear a brand new song (Oriole J). The singer is throwing all sorts of variations and it's got a couple of harsh notes in the middle which sometimes it extends into a full chatter.

It moves along the river until it reaches the point, where it sits and sings and displays dominance over at least one competing male.

May 16, 2012. Another rainy morning walk at the Charles River Peninsula.

Oriole G
Oriole I
Zone 6 oriole
It's raining again. I take some quick photos of Oriole G in the parking lot (zone 1) and capture a clear recording of his song.

By the time I get to the top of the driveway it is pouring rain. This is where Oriole A is now singing  (zone 1 1/2?) and where he continues to respond to his song twin (Oriole B) across the river.

I walk down the entrance path. It has become very quiet. I listen for a while at the entrance. Also quiet. When I enter the woods (zone 3) I hear clearly Oriole B from across the river.

It isn't until I arrive at nesting box 5 (zone 4) that I hear any real continuous singing.

This seems familiar but I can't place it. I'll call it Oriole I. It flies down and rudely bumps a song sparrow off its position on a branch.

Out at the overlook (zone 5) I hear a faint rendition his song from Oriole J.

He seems to have settled closer to the river.

At the point (zone 6) there is, as usual, lots of activity. More female than male singing. In the woods (zone 7) I catch this exchange. 

Sounds like Oriole M and Oriole G(?!?!). But wasn't Oriole G just singing his heart out at the parking lot? It dawns on me that Oriole G might be another song with more than one singer. I begin to lose confidence that I understand anything about Baltimore Orioles...

It is raining harder now. I see something at the edge of the woods. It is a couple of white-tailed deer strolling by. I follow them back to the point, where they disappear into the vegetation. The male from the woods (Oriole "G") is here now in an apparent conversation with another female (Oriole P).

As I stand by the point listening I watch a vicious song sparrow chase and catch a whiff of northern parula song. I fail to find the parula.

I walk down to the train tracks (zone 9).  Continuous song from Oriole V

and sporadic song from Oriole Y.  More drama today as two males compete over a female (though I cannot say for sure who the female and the other male were). Our singer is the victor...for now...

May 17, 2012. A quick morning visit to the Charles River Peninsula parking lot.

I had time to pop by the CRP in the morning. Time to confirm that Oriole G (or his doppleganger) was still presiding over things there.

May 17, 2012. An oriole from Chestnut Hill Farms

I drove over to Southborough to check out the bobolink situation there. While I was there I collected another delightful Baltimore oriole song. Here's a fragment.

May 17, 2012. An afternoon stroll through Charles River Peninsula.

I should know better than to expect much oriole singing in the afternoon, particularly this late in the season. And I'm right--except for the parking lot. Has Oriole G been singing all day?

May 18, 2012. A brisk morning walk through the Charles River Peninsula

Things have been quiet for the last few days now. I think the Baltimore orioles are beginning to withdraw from the spotlight for a while. This does not include, of course, Oriole G at the parking lot, who is still going strong. In other news, it appears that Oriole I has moved across the river. You can hear his faint song. And Oriole J is still singing faintly from the huge tree at the river's edge.

May 21, 2012. A quick visit after a few days absence from the Charles River Peninsula

Given the decline in oriole song at the CRP it is no longer a priority, but I stop by to check on nesting boxes and record what I hear. And although there is still activity and sporadic singing among the male and female Baltimore orioles, once again it is only the parking lot where there is any consistent song (yes, Oriole G), and that too is growing more and more sporadic.

May 26, 2012. A sunrise visit to the Charles River Peninsula.

I make it to the CRP for the tail end of the dawn chorus. Orioles are singing but I understand now why parabolic microphones are so useful. It is very difficult to pick out individual songs in the dense sound of everyone singing at once. Today is my first "grassland bird monitoring" day this year. I stand out in the middle of each of the fields and record what I hear. No bobolinks. Maybe a savannah sparrow. And this oriole, probably Oriole V, who provides a nice capper to this project (for now). The simplest, blankest song possible...

May 31, 2012. Mid-morning oriole nest check (and song map update) 

The nest in zone 3 is now obscured by leaf growth so the only nest that is visible is in zone 7. We already know the players. The male is Oriole M, the female is Oriole F. In the video below, she is in the nest when he sings. She responds and flies out of the nest. In the second scene, I assume she is in the nest (though there is no singing from either one) and he pops in, probably to feed her. He evidently hears something he doesn't like (perhaps dogs barking) and pops out of the nest.

In other news: a delightful new singer, with many variations, shows up in zone 4. I'm all out of letters. How about Oriole alpha?

And just when I think things have stabilized, who should show up along the entrance path (zone 2) but Oriole V, last heard far away in zone 9.

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