Yellow-rumped warbler, Frick Park, 26 Oct 2023 (photo by Charity Kheshgi)
5 November 2023
Some days it seems like all the birds are turning their backs on us. Warbler season is especially challenging because they tend to pose just like the yellow-rumped warbler above. Fortunately The Warbler Guide by Tom Stephenson & Scott Whittle includes a butt-shot for every bird so if you take photographs you can look them up when you get home.
Most birds just happen to be facing away but others, like this hermit thrush, do it intentionally. The thrush was keeping an eye on us while he hid in the shadows with an escape route mapped out ahead of him.
Hermit thrush presents his back and keeps an eye on us, Frick Park, 26 Oct 2023 (photo by Charity Kheshgi)
Kinglets face every which way as they busily flit to find tiny insects. Inevitably they end up in a butt shot.
Ruby-crowned kinglet, Frick Park, 26 Oct 2023 (photo by Charity Kheshgi)
Sometimes we see a new feature of the bird from behind. This golden-crowned kinglet shows a bit of red at the back of his yellow crest …
Golden-crowned kinglet showing a hint of red in his crest, Frick Park, 26 Oct 2023 (photo by Charity Kheshgi)
… as seen in this closeup.
Closeup of golden-crowned kinglet’s head with hint of red in his crest (photo by Charity Kheshgi)
Surprisingly, some sparrows have faces on their back ends as seen in Wes Iversen’s photo of a fluffed up sparrow. Notice how the secondary wing feathers, back, and undertail coverts form eyes, nose and smiling mouth. The photograph is embedded from Wes Iversen’s original here on Flickr.
On 18 October while Jim McCollum was taking photos of the Hays bald eagles a raven showed up and began to harass the new male eagle, nicknamed “V.”
10/18 – The new fella went for a fly about and got jumped by a Raven. The Raven chased him all over the sky. This guy needs to work on his fighting skills.
A little tidbit I read recently. Crows will lite on eagles backs and peck at their necks. The eagles don’t fight back just soar higher and higher until for lack of oxygen the crow passes out and falls off the eagles back. I’m not sure about the validity but it’s a good story!
At what altitude does lack of oxygen affect birds?
Birds are the champions of high altitude and can breed and exercise (fly) at altitudes that kill humans. Some species are so well adapted to high altitude that they fly as high as a jet, over the Himalayas where humans die without supplemental oxygen. Even our North American songbirds fly high …
Migrating birds in the Caribbean(*) are mostly observed around 10,000 feet, although some are found half and some twice that high. Generally long-distance migrants seem to start out at about 5,000 feet and then progressively climb to around 20,000 feet.
This month a flock of 100 to 200 common grackles has been hanging out at Frick Park, chattering in the trees and swirling in a dense flock whenever they’re disturbed. This is typical fall behavior for grackles and blackbirds but I wondered why they picked the park.
According to Birds of the World, common grackles (Quiscalus quiscula) are not very territorial during the breeding season and drop all rivalry in fall and winter. On migration and at overwintering sites they prefer to roost and feed in huge flocks, sometimes mixed with other blackbirds and some robins.
Common grackles roost near plentiful food but they don’t require wild places. Urban roosts are often favored on tree-lined streets or in parks. Their fall roosts in New Jersey can contain 3,000-500,000 birds (of which grackles comprise 33%).
This flock at Patuxent in Maryland looks to be 100% grackles.
The huge grackle flocks probably won’t stay in southwestern PA for the winter. By December they are further south, as shown on the eBird Dec-Feb map below.
Like elephants, albatrosses can hear low frequency sounds below our range of hearing, a skill that’s very useful for their lifestyle.
Wandering albatrosses (Diomedea exulans) spend their lives making incredibly long journeys over the ocean. They are known to circumnavigate the Southern Ocean three times in one year, a distance of more than 75,000 miles (120,000 km).
To do this with the least amount of effort, they have the longest wingspan of any living bird — 8 to 12 feet (2.5 to 3.66m) — and use the wind to glide as much as possible.
The best gliding happens at updrafts over the water and the best updrafts are caused by large waves. So how do wandering albatrosses find those large waves? They hear them from very far away, possibly 1,000 miles.
According to Science Magazine, “Big waves produce a very low frequency sound, below 20 hertz, that can travel thousands of kilometers, particularly when they collide with long distance swells, such as when storms develop.”
Would an albatross approach or avoid these waves in the Southern Ocean?
To figure out how the birds choose where to go, Samantha Patrick of University of Liverpool and her team tagged 89 albatrosses with GPS trackers at their breeding grounds on Crozet Island near Antarctica. When the birds returned a year later to breed again, researchers retrieved the tags and analyzed the data.
Geophysicists on the team combined the biologger recordings with infrasound monitoring data from Kerguelen Island in the Southern Ocean to build “soundscape” maps on the birds’ journeys. …
During their long-distance flights, the birds tended to change course whenever they encountered a loud infrasound, the team reports. The infrasounds often indicate wave turbulence, even storms—though it’s not yet clear how the birds make use of this information. The infrasound clearly impacted the birds’ behavior, although the scientists couldn’t identify a clear pattern of whether they avoided or aimed for these low frequencies.
When peregrine falcons migrate down the Pacific Coast in autumn they often pause at Canada’s Fraser River Delta to hunt shorebirds. Pacificnorthwestkate (@pnwkate) filmed one working a sandpiper flock at Roberts Bank.
Peregrines on the hunt hope to separate a single bird from the crowd because they cannot catch anything in such a tight flock. When a lone bird can’t keep up it becomes the peregrine’s dinner.
A new study, published this month in Phys.org, looked at the interaction from the peregrines’ perspective and found that the falcons haze the dunlin flocks to keep them moving. Peregrine hunting success improved at the end of those 3-5 hours of continuous flying because the dunlin had to stop for a rest.
The hunting data showed that dunlins were at greatest risk of predation just before and just after high tide, and spent most of the riskiest period flocking. However, there was a sharp increase in kills two hours after high tide, because the dunlins were not flocking despite elevated risk. [They were resting.]
So the dunlin changed their behavior to avoid peregrine predation and the peregrines changed their behavior to wear out the dunlin. Peregrines have more stamina that dunlin.
The region around the Gulf of Naples is very volcanic. There are vents at Solfatara in Pozzuoli where sulfurous steam emerges in an old crater. Pompeii and Vesuvius are across the Gulf.
Nonetheless it’s a lovely place to live by the Mediterranean. Towns, including Pozzuoli, Agnano and Bacoli, dot the crater edges and the flats between them. The area’s population is 500,000.
In September the magma under Campi Flegrei began shifting again and caused more than 1,100 earthquakes in a month, some as strong as 4.0 and 4.2 on the Richter scale. The Guardian reported on 3 October: “The Italian government is planning for a possible mass evacuation of tens of thousands of people who live around the Campi Flegrei supervolcano near Naples.”
Years ago I learned that birds can sense when an earthquake is coming and they take flight before it hits. I suspect that the birds at Campi Flegrei are flying more than usual lately.
Read more about birds and earthquakes in this vintage article from 2016.
Woolly bear, Isabella Tiger Moth caterpillar, 3 Oct 2018 (photo by Kate St. John)
6 October 2023
In October we see woolly bear caterpillars (Pyrrharctia isabella) out in the open, crossing the trails. Because they overwinter as caterpillars, they’re busy looking for the perfect place to spend the winter in leaf litter, under bark or beneath a fallen log.
Fallen leaves in Schenley Park, Nov 2016 (photo by Kate St. John)
Leaf litter is key winter habitat for a lot of insects including springtails, millipedes, earthworms, butterflies and moths.
Millipede(*) Hays Woods, Sept 2023 (photo by Kate St. John)
If you’ve been thinking about “wilding” your yard — even just a little bit — now is a great time to start. Leave the leaves. You don’t have to leave it messy. Here’s advice on what to do.
Leaving the leaves and other plant debris doesn’t have to mean sacrificing your yard to the wilderness. The leaves don’t need to be left exactly where they fall. You can rake them into garden beds, around tree bases, or into other designated areas. Too many leaves can kill grass, but in soil they can suppress weeds, retain moisture, and boost nutrition.
Avoid shredding leaves with a mower. Raking or blowing are alternatives that will keep leaves whole for the best cover and protect the insects and eggs already living there.
If you decide you need to clean up the leaves and debris in spring, make sure you wait until late in the season so as not to destroy all the life you’ve worked to protect.
Take a break this weekend. Don’t bag those leaves! Just push them aside for wildlife. 🙂
(photos by Kate St. John and from Wikimedia Commons)
(*) p.s. The millipede was easy to photograph because it was dead, probably the victim of a parasitic fungus that prompts the millipede to climb high on a twig before it dies. I wrote down the name of the fungus when I took the picture but cannot read my writing. Perhaps it’s Anthrophaga myriapodia.
The blackpoll’s transoceanic path was proven in a 2015 study by Bill DeLuca and the Vermont Center for Ecostudies. VCE writes:
Bill DeLuca (Northeast Climate Science Center) and VCE solved this great modern-day avian mystery. Using light-level geolocators attached to Blackpoll Warblers in Vermont and Nova Scotia, DeLuca and colleagues documented the longest distance non-stop overwater flights ever recorded for a migratory songbird. During October, Blackpoll Warblers initiate a ~3-day non-stop transoceanic flight of ~2500 km from the north Atlantic Coast to Hispaniola and Puerto Rico. Radar data show migrating songbirds fly at 2,600 to 20,000 feet while making this journey. After a few weeks, they fly onto Columbia or Venezuela where they overwinter. Their spring migration route takes them over Cuba to Florida, where they journey up the eastern US seaboard to reach their breeding grounds in late May.
Of course I wondered if blackpoll warblers sleep in flight during their 3 day transoceanic trip, but we won’t find out any time soon. Blackpolls are way too small to wear the sleep monitoring gear used on the great frigatebird.
(photo from Wikimedia Commons, maps from eBird Weekly Abundance; click on the captions to see the originals)
On Saturday 17 September, my friends Mary and Bea were walking to the Bloomfield Saturday Market when they couldn’t help but notice a red-tailed hawk (Buteo jamaicensis) hunting on the lawn at Shadyside Hospital. Mary stopped to take his picture.
Perched on the blue sign, I can tell the bird is immature because his tail isn’t rusty red. In early June he was still in the nest. Soon he learned to fly, then to hunt. Now, months later, he can feed himself but he’s not an expert. It takes time and luck to get a meal.
In autumn young red-tails disperse on their first migration and every place they stop is completely new to them. Those that grew up in urban environments are unbothered by traffic and people so they may gravitate to open areas near buildings in search of prey.
This hawk was so focused on hunting that he ignored Mary while she took his picture. Read more about the hawk’s single mindedness in this article from 2009.
p.s. This red-tail may have been attracted to the noise of house sparrows tweeting inside that bright green hedge. There are always lots of them in there, but they shut up as soon as I look so I rarely see one. As far as I know, I’m the only one — other than a hawk — that peers inside that hedge. 😉
Two juvenile Cooper’s hawks in Frick Park, 14 July 2022 (photo by Charity Kheshgi)
22 September 2023
Every year young Cooper’s hawks (Accipiter cooperii) fledge in June/July and learn to hunt in July/August. As soon as they’re self sufficient they disperse, and then they start to migrate.
Cooper’s hawks eat birds for a living so they migrate with their prey. Their peak migration continues now through mid October at the Allegheny Front Hawk Watch.
How did they get to this point? Let’s take a look back to August as some young Cooper’s hawks perfect their hunting techniques in New Jersey. It involves a lot of jumping.
