Dawn Chorus Update #15: Closing Out the Dawn Chorus at Colonial Creek Campground

[Stephen Chase]

Hello Whatcom Birds,

It's July now, so the dawn chorus is done, right? Not at all, actually! Yesterday morning at Colonial Creek Campground near Diablo, the early morning avian routine sounded just like it has been since mid-May: just another intense dawn chorus! It began at 4:08 AM (62 minutes before sunrise!) with a Spotted Sandpiper on Diablo Lake. Four minutes later an American Robin began singing; in fact, it was three robins, a trio of testosterone-infused robins singing 20 yards apart, with me smack dab in the center! Within minutes Song Sparrows, White-crowned Sparrows, Hammond's Flycatchers, and Yellow-rumped Warblers joined the chorus. By 4:50 (20 minutes before sunrise), the dawn chorus included Western Tanagers, Varied Thrushes, Golden-crowned Kinglets, Western Warbling Vireos, Swainson's Thrushes, and more. Take a listen!

As the birds transition from raising nestlings to feeding fledged birds, there are noticeable changes in the progression from the dawn chorus to daylight. Most obvious is the near-eerie silence after the dawn chorus subsides. During spring, I've found that songbirds are more likely to continue singing while they forage. By July, the birdsong can be sparse in the hour after sunrise. Despite the vibrant song only minutes before, there were some moments after the sun rose where I heard not one singing bird. The silver lining is that when a bird did sing, I could isolate the individual to capture excellent audio recordings, such as this haunting Swainson's Thrush.

However, just because birds weren't singing doesn't mean they weren't active. Most exciting of all was the activity on and under the Colonial Creek bridge over Diablo Lake. Barn Swallows and Cliff Swallows hawked for bugs for their nestlings hidden under the bridge, while an enormous flock of Evening Grosbeaks (and two deer) foraged for salts and other minerals on the bridge deck itself. Take a look at this stunning photo Josiah captured of a friendly grosbeak! Unfortunately, the foraging grosbeaks were being decimated by vehicle strikes. I counted 82 dead grosbeaks on the bridge. Via social media I've reached out to WSDOT about this issue, but if anyone has a more direct connection, please help me get the word out. A sign warning travellers of wildlife or a road cleaning to rid the bridge deck of enticing minerals might be two possible solutions.

My morning walk at Colonial Creek Campground (complete checklist link here) was just one part of a two-day trip with my sons Josiah and Titus into the North Cascades National Park area. We came here in search of exciting montane species such as Canyon Wren, Black-backed Woodpecker, and Red-naped Sapsucker. (Spoiler alert: we found all three species, and a few extra rarities to boot!) If you're interested, explore our complete trip report on eBird. (Some of the rarities we found are pending eBird review, so you may need to click through the seven checklists to see all the photos.)

As we're now well into summer and the dawn chorus will slowly fade, this will be my final update for this dawn chorus series. One of my goals with this series was to keep the conversation alive on our Whatcom Birds listserv. We have a valuable forum here with birders/birdwatchers who collectively share a wide range of experiences and knowledge, and that is to be treasured! Although most of the communication I've received has been via personal replies (not publicly via the listserv), I've appreciated the positive feedback and interactions. Some of you were inspired to rise early to experience your own dawn chorus, others began experimenting with spectrograms, and many shared that you enjoyed following along through these weekly updates. I encourage you all to keep these sorts of conversations going - and don't be afraid to make them public on this listserv. We learn well from each other, especially since we share an interest in birds. Let's keep this forum alive!

I've got some ideas for future birding series, but for now, I'll yield the floor. Thanks for following along through the breeding season.

In Everson,

Stephen Chase