20 June 2021

Tomorrow Stonehenge will have its biggest day of the year even though no one can be there to see it. The prehistoric monument in Wiltshire, England usually attracts a crowd of 30,000 to watch the sun rise over the Heel Stone on the summer solstice but a new COVID-19 surge canceled the festivities. The sun will rise anyway, shining on stones imported from Wales.

Constructed in phases, Stonehenge began as an earthworks 5,000 years ago with a bluestone (Heel Stone) outside the main entrance oriented toward the summer solstice. Later phases added bluestones in a ring, a horseshoe and other key locations. Then sandstone monoliths were added to surround the bluestones. After maintenance ended about 3,600 years ago the site slowly fell apart.

Since the 1600s archaeologists have worked to uncover Stonehenge’s configuration, building phases and purpose. They easily discovered that the sandstone monoliths came from local rock but it took a long time to figure out that the first stones, bluestones of igneous dolerite weighing 2 to 4 tons, came from a prehistoric quarry in the Preseli Hills in Wales, 140 miles (200 km) away.

The stones were well worth moving.

Researchers from the Royal College of Art in London discovered that the monument’s igneous bluestones possess “unusual acoustic properties” – when struck they respond with a “loud clanging noise.” … In certain ancient cultures, rocks that ring out were believed to contain mystic or healing powers.

— Wikipedia’s Stonehenge account

But there was a gap. The Presili quarry closed 200-500 years before Stonehenge began. Where were the stones in the intervening centuries?

Researchers led by University College London archaeologist Michael Parker Pearson searched for ritual structures in the Preseli region that might have provided the stones—and the blueprint—for Stonehenge. In 2017 and 2018, they excavated parts of an ancient monument called Waun Mawn, where a handful of toppled bluestones similar to those at Stonehenge form a partial circle.

— Science Magazine: England’s Stonehenge was erected in Wales first

The clincher was that an unusually shaped stone at Stonehenge has a matching hole at Waun Mawn.

You can see how the stones were transported 5,000 years ago at English Heritage, Stonehenge. Read more about the discovery in The Guardian.

When the sun rises over the Heel Stone at Stonehenge tomorrow, it will touch many rocks imported from Wales.

(photos from Wikimedia Commons)

p.s. The illustration linked here from creatureandcreator.ca by Terence W. Picton, makes it easier to understand the bluestones (blue) and sandstones (orange). Picton explains that his diagram is based on two illustrations from other sources: Johnson, 2008, p. 166 and the English Heritage Webpage. It does not include the Avenue and Heel Stone.

14 June 2021

Very soon Pennsylvania birders will reach our annual psychic low point. If you watch peregrine or bald eagle nestcams you’re already there. Spring migration is over and the nestcams are quiet. Soon the birds will stop singing. We are bound to feel let down after so much excitement.

I was reminded of our emotional roller coaster when I rediscovered “The Birder’s Year” graph posted in 2014 on the The Birders Conundrum blog. Back then bloggers Sam Jolly @JollyBirding and Lucas Bobay @BirderBobay were avid birders in high school in North Carolina. They have since moved on, still birding not blogging, but their website is alive at The Birders Conundrum so you can see their original graph here.

The moment I saw their graph I realized that mine is a slightly different. I get excited in February and March when peregrines court and lay eggs. Incubation is boring in April but migration heats up in May and the nestlings are on the falconcam. Even so, I reach the same trough in July as the rest of Pennsylvania’s birders. You can see this on my altered version of Sam and Lucas’s graph which I’ve labeled The Peregrine Birder’s Year.

Perhaps you’ve noticed too that we’re heading for a low point in The Birder’s Year.

p.s. In the graph above CMWA = the last Cape May Warbler, CBC = Christmas Bird Count

(photo from Wikimedia Commons, graph altered from one by Sam & Lucas at The Birders Conundrum)

13 March 2021

We’re about to lose an hour’s sleep, annoy our pets, and be crabby for a couple of days. Tonight we turn the clocks forward to Daylight Saving Time. It turns out this change is optional.

In 2019 the European Parliament voted to allow each EU nation to decide on its own if it wants to adhere to Daylight Saving Time (DST) starting in 2021. If a nation decides to keep Standard Time, it would change its clocks in October/November and never change again. If it decides to stay with DST it could change this month and stay in permanent DST. Interestingly if the UK (no longer in EU) and the Republic of Ireland (EU member) have different ideas about DST they could create two time zones where there has been only one.

In the U.S., each state is allowed not to participate in Daylight Saving Time (DST) but it requires the state legislature and Congressional approval to use DST year-round. Arizona, Hawaii and six U.S. island territories do not use DST while 13 U.S. states have begun the slow legislative process of making Daylight Saving Time permanent.

So changing our clocks tonight is optional. A country can decide not to do it. A state can decide not to do it. We as individuals have the freedom not to change our clocks, even if we live in a U.S. state that uses Daylight Saving Time.

You don’t want to change your clocks? Don’t change them.

Tell me how it goes.

(*) p.s. I’m pretty much a rule follower so I will change my clocks. Also, I like DST.

If you chose not to change your clocks you will have to fuss with your Internet-connected devices that change automatically. You can force your cellphone to use the time you want by changing Settings > System (or General) > Date & Time > then un-checkmark “Use network-provided time” and “Use network-provided time zone.” Set whatever time you want. Good luck.

(photo and clock GIF from Wikimedia Commons)