The Golden Spike at Crawford Lake: field trip

On Thursday, November 2nd, Mark Whitcombe will lead a field trip to the Crawford Lake Conservation Area, just south of Campbellville (south of the 401 and west of Milton). As of Tuesday October 31st, we have a dozen members coming, with two car-pools set up.

(Please note that the date for this trip is
still Thursday November 2nd at 10 A.M.,
not the incorrectly reported date of two days later.
See you at Crawford Lake this coming Thursday!)

The Field Trip to the Golden Spike:

We’ll arrive at Crawford Lake Conservation Area (Halton Region CA) for 10 A.M. next Thursday November 02, 2023.  We are arranging how much each car and driver has to pay, and how much each participant has to pay.  (Headwaters Nature is not paying for this field trip. As individuals, we are covering the costs ourselves. We are getting a cheaper rate through a Group Booking. Watch for updates to this page — and keep an eye on email updates.

I would like to specifically visit the lake itself. The meromictic sediments in this special lake show very clearly that we humans have left an irreversible imprint upon Earth’s geology. Data from the sediments at the bottom of the unusual Crawford Lake show a clear footprint of plutonium from the nuclear testing done in the late 1940s and early 1950s — data that also shows in various other locations around the world. This location has been proposed as the ‘Golden Spike’, the location on Earth that clearly shows the beginning of the epoch now being proposed to be called the Anthropocene, “the geologic age when Humanity left an irreversible imprint upon Earth’s rocks”.

  • We’ll meet at Crawford Lake Conservation Area itself, at the parking lot inside the main gate off Guelph Line, a couple of kilometres south of Campbellville and the 401.
    • 3115 Conservation Rd, Milton ON L9T 2X3, Canada
  • Please alert the staff at the gate that you are part of the group coming from Headwaters Nature to look at the Golden Spike. They’ll tell you where to park.
    • We are getting a Group Rate, that they will alert you to at the Gate.
    • Route to Crawford Lake:  approximately 71 km / just over an hour from Orangeville on Guelph Line, a couple of kilometres south of Campbellville, which is directly south of where the Guelph Line crosses the 401.
      • Here’s an openable two-page document that includes the general location of Crawford Lake as well as a trail map:  TrailGuide_CrawfordLake

If you notify me ( that you’re coming ahead of time, I will attempt to help you set up possible carpooling arrangements.  

  • We will be strolling a slow botanist’s pace around Crawford Lake, about half on a flat boardwalk, with some gentle slopes down to and back up from the Lake. The walk would take approximately an hour if we didn’t stop to observe and chat, so I’m suggesting a two hour ramble.
    • I might even bring a small lunch and something to drink for myself while I enjoy this field trip …
      • There are other options you may wish to consider for yourselves afterwards, apart from this short Headwaters Nature field trip. (I will be coming back home instead of staying at Crawford Lake.)
        • There is an good small gift shop (for books!) and some displays at the main centre of the conservation area near the parking lots.
        • There is a partial re-creation of a Wendat or Attawandaron village dating from C15 that was actually discovered partially based on pollen records from bottom of Crawford Lake just over 50 years ago. Lots to see!
        • There is an excellent but more challenging 4–5 hour hike, the Nassagaweya Canyon Trail, to Rattlesnake Point and back that you can get to directly from the parking lot.

If you are coming (or have further questions),
please let me know so that I can plan this field trip!
Mark Whitcombe,

The Anthropocene

In July 2023, Crawford Lake was chosen as the “golden spike” by the Anthropocene Working Group as the clear marker for the beginning of the Anthropocene epoch. The unique conditions of the lake preserves layers of sediment similar to tree rings used in dendrochronology — and the presence of plutonium in the layers of lake mud dated to 1950 has been set as the beginning of the new proposed epoch.
Studying everything from atomic bomb fallout to pesticide residues, scientists are close to defining the start of the Anthropocene — the geologic age when Humanity left an irreversible imprint upon Earth’s rocks.
In July 2023, Crawford Lake was proposed as the “golden spike” by the Anthropocene Working Group as the clear marker for the beginning of the Anthropocene epoch. The unique conditions of the lake preserves layers of sediment similar to tree rings used in dendrochronology; the presence of plutonium in the layer of lake mud dated to 1950 has been set as the beginning of the new proposed epoch.
Perhaps the most famous Golden Spike are the telltale signs found in many spots around the world of the meteorite that crashed into Earth 66 million years ago, killing off dinosaurs and starting the Cenozoic Era, or what is conversationally known as the age of mammals. But not quite. While that meteorite started a whole new era, the working group is proposing that humans only started a new epoch, which is a much smaller geologic time period.

* –  * – * – * – * – * – * – *

Ahead of time, you might wish to check this recent video
and excellent explanatory writeup
from Emily Chung, science, climate, environment reporter, (CBC):

Birder Murder Mysteries: A Foreboding of Petrels

Steve Burrows, the author of seven Birder Murder Mysteries, will be back speaking with Headwaters Nature telling us about his latest story of DCI Dominic Lejuene, a Canadian birder working as a detective. Lejeune uses his advanced birding knowledge to help him solve (at least one) murder in the quiet countryside of Norfolk, UK. His latest book is called A Foreboding of Petrels. (I’m going to read up on Petrels before Steve speaks … and before I read his book. By the way, BookLore will be attending this meeting to sell his books.

Join us Tuesday evening, 7:00 – 9:00 P.M., October 24th,
at the Orangeville Seniors Centre at 26 Bythia Street.
Free Admission,

Everyone Welcome,
Refreshments provided,

Bring your own mug.

Burrows is a wonderful storyteller and an entertaining speaker. He says he’s happiest talking to groups such as ours who instinctively understand the nuances of bird behaviour that he weaves through his writing.

Steve first began exploring nature in the urban parks of his childhood home in Birmingham, UK. After emigrating to Canada, he eamed degrees from York University and Dalhousie University before relocating to Hong Kong, where he earned a Master’s degree from the University of Hong Kong. His dissertation explored the feasibility of reintroducing Silver Pheasants into Hong Kong’s forests.

Check out his website at Steve Burrows


Our roster of upcoming Speakers:

    • Nov 28/23: Don Scallen: Turtles of Ontario
    • Dec (late):  Christmas Bird Count:  details coming in the next month
    • Jan 30/24:  Gary Hall: How a photographer sees nature
    • Feb 27/24: Robin and crew, Nature Nerd Night — oh, the fun!!!
    • March 26/24:  Sarah Griffith: Clear as Mud – Using Geoscience for Decisions, Advice, and Accountability
    • April 30/24:  Fiona Reid:, Moths and Butterflies as Pollinators
    • May 28/24:  Jennifer Baici: Wild Turkeys in Ontario: a life history

(Details about each session will come out in the month before the actual event.)