Yearly Archives: 2019

The Measure Of A Mouse

What size of a hole can a mouse get through? If you have ingenuity, time, and tools you can find out.

Matthias Wandel of woodgears.ca takes an engineering approach to woodworking. When a mouse got into his woodshed he made a wooden gauge to find the smallest hole the mouse could squeeze through. His seven-minute video, above, became an Internet sensation.

The mouse tried many holes but gave up quickly if they were too small. What limits the mouse from squeezing through? It’s the size of his skull, not the size of his belly that stands in the way.

Near the end of the video a shrew appears. What limits the shrew?

(video by Matthias Wandel of woodgears.ca. click here for more of his videos)

Prankster on Camera

Last week Colin Roberts tweeted this video from one of his forest trailcams in southwest Scotland. His cameras record the activities of pine martens but the view is sometimes dominated by another species, the Eurasian jay.

Eurasian jay (photo by Pierre Dalous via Wikimedia Commons)
Eurasian jay (photo by Pierre Dalous via Wikimedia Commons)

Eurasian jays (Garrulus glandarius) are intelligent, curious, and very vocal mimics. This particular jay punctuates his visits with the sounds of a squeaky tree, a tawny owl, and an amazing Star Wars riff.

Then he gets really close to the lens and … oh my!

(tweet and video by Colin Roberts @PinetenColin, photo from Wikimedia Commons)

Remembering Louie: 2002 – 2019

In late June, after five young peregrines fledged from Pittsburgh’s Third Avenue nest, their father Louie was found dead at age 17. He was exceptionally old for a wild peregrine but longevity was in his genes.

Louie hatched in 2002, the son of Dorothy and Erie during their first successful year at the Cathedral of Learning. Dorothy fledged 43 young at Pitt before she disappeared at age 16.5.

Dorothy was the daughter of Sibella and Bill who were both part of The Peregrine Fund‘s Midwest Peregrine Recovery Program. Sibella nested at the First Wisconsin Building in Milwaukee through her 15th year. With a long-lived mother and grandmother it’s no wonder Louie made it to 17.

Louie started breeding early. In 2003 he was one year old when he won Pittsburgh’s Downtown territory. It was a tumultuous spring with two females and two males vying for the Gulf Tower nest. In the end Louie fought and killed Boris at the nestbox and became Tasha’s mate.

From 2003-2009 Louie fledged 24 young with Tasha. In her last breeding year he was especially protective of her on Banding Day.

The next year, 2010, was Louie’s chance to shine. In late March Dori defeated Tasha and became a first-time parent. Louie showed her the ropes as described in the links below:

Louie was versatile. In their years together he and Dori moved their nest from year to year using three sites to fledge 39 young.

In 2012 they chose a cubbyhole on 3rd Avenue where they’ve nested 5 times. In 2015 they nested at Macy’s Annex. In 2014 and 2017 they returned to the Gulf Tower.

2018 ended sadly at Third Avenue when the Keystone Flats development was granted a Special Takings Permit and had their chicks removed. This year they were back at Third Avenue to raise and fledge five young. Louie was a good dad to the end.

All told Louie fathered 63 young peregrines. Like his mother Dorothy, Louie was the head of a dynasty.

(photos by Brian Cohen, Ann Hohn, Lori Maggio, Maria Ochoa, Matt Orres and the National Aviary falconcam at Gulf Tower)

Peregrine Fledging at 62nd Street Bridge

On Wednesday July 3, Joe Stavish of Tree Pittsburgh saw an immature peregrine standing on a rock pile in Tree Pittsburgh‘s parking lot below the 62nd Street Bridge. Joe emailed me:

I found an immature peregrine in the parking lot at Tree Pittsburgh (under 62nd street bridge) on Wednesday, July 3, 2019. We have noticed [peregrine] adults flying around the tree nursery this spring. This one was a bit clumsy moving around the rock pile but ultimately flew off. I could not see any band on the legs. Not sure if it came from the 62nd street bridge but perhaps!

Joe Stavish email, 5 July 2019

Here’s a Google Street View of that end of 62nd Street. Tree Pittsburgh is beyond the chain link fence on the left side of the image, though it didn’t exist when Google took this photo.

At this point (early/mid July) it’s too late to find the peregrines’ nest but keep an eye out for them beginning next January at the 62nd Street Bridge.

NOTE! A nestbox was installed on the bridge in January 2008. If it’s still on the bridge the peregrines might be using it.

In January 2008 a nestbox was installed at the 62nd Street Bridge (photo from PGC). Is the nestbox still there?

Look Under The Leaves

Milkweed blooming at Schenley Park, 26 June 2019 (photo by Kate St. John)

All across western Pennsylvania a wide variety of milkweed is blooming and with it come the insects who depend it, especially monarch butterflies.

Look closely at the underside of milkweed leaves. If you find a small white dot it’s a monarch butterfly egg.

The plant I found didn’t have monarch eggs, but here’s a photo from Wikimedia Commons that shows you what to look for.

Monarch butterfly egg on underside of milkweed leaf (photo from Wikimedia Commons)

I hope the milkweed leaves in Schenley Park have eggs soon …

(photos by Kate St. John and from Wikimedia Commons)

Incredibly Hot in Alaska

Alaska high temperature forecast for 7 July 2019 (map from National Weather Service)

Don’t be fooled by the happy green colors on the watery edge of this map. The high temperature in much of Alaska tomorrow will be 85 degrees F.

Alaska is baking under a five-to-seven day heat wave caused by exceptionally strong high pressure that will break most temperature records. Alaskans aren’t prepared for it. The normal high in Anchorage this week should be 67 degrees F but that’s close to what the low will be (61).

The deepest red on the map is in the southwest interior near the Kuskokwim River where the temperature will soar up to 95 degrees. This area suffered last winter, too, when an early thaw shut down transportation to 13,000 people.

Not only will it be hot in Alaska but it will be hard to breathe. Baking temperatures, dry vegetation and lightning have ignited huge forest fires across the state. The Sunday 7am forecast for much of Alaska includes “areas of smoke” shown in gray below.

Alaska Predominant Weather forecast for 7 July 2019 (map from National Weather Service)

There’s only one place left that’s truly cold. That cold dot on the map is the peak of Denali.

Where is it cold in Alaska?

(maps from the National Weather Service; click on the captions to see the graphical forecast for Alaska)

Happy Fourth Of July 2019

Juvenile eagles H9 and H10 at Hays Woods, 30 June 2019 (photo by Dana Nesiti, Eagles of Hays PA on Facebook)

News from Hays Woods in Pittsburgh, PA:

This week the young bald eagles, H9 and H10, turned 100 days old. Dana Nesiti captured their antics on Sunday June 30 in the photo above and a slow motion video below.

Visit Dana’s Eagles of Hays PA Facebook page for more news, photos and videos of the Hays bald eagles.

Happy Fourth of July!

By the way, Pennsylvania now has so many bald eagle nests that the PA Game Commission can’t count them without your help. See Mary Ann Thomas’ TribLive article here.

(photo and video by Dana Nesiti, Eagles of Hays PA on Facebook)

Beat The Heat With Trees

Schenley Park Upper Trail, July 2017 (photo by Kate St. John)

3 July 2019

It’s been hot in Pittsburgh lately but nothing like the heat wave that’s sweeping Europe with highs above 100 degrees F. @JeremyDBarrell tweeted a long term solution with a compelling image by Meg Caffin.

Meg Caffin is an urban forest consultant from Australia who provides guidance for cities looking to beat the heat. Her image at top used an infrared camera to show the temperature difference between a paved churchyard and the trees behind it. I’ve made a Fahrenheit translation below. Yes, it’s 113oF on the pavement and only 77oF under the trees.

Tree shade is cooler than building shade because buildings merely block the sun while the trees actually lower the temperature.

Schenley Park near Bartlett entrance (photo by Kate St. John)

Trees cool the air by transpiring. They take up water from the ground and release it from the stomata in their leaves. The release doesn’t usually drip from the leaves as shown below. Instead it evaporates and that’s what cools the air.

Transpiration droplets from a leaf (photo from Wikimedia Commons)

Evaporation — changing a liquid to a gas — uses energy. According to the Transpiration blog, “Energy is absorbed into liquid water. This reduces the temperature of the surrounding plant tissue and nearby atmosphere. To evaporate 1 gram of water 590 calories of energy is required.”

So more trees mean less heat.

If that isn’t enough reason to like trees, here’s another benefit. Trees increase your property value as shown in the EPA cost-benefit analysis below.

Trees increase property value far beyond cost of maintenance (EPA)

Plan to plant a tree this fall or plan to keep one. It’s cheaper to keep an existing tree than to plant a new one and mature trees increase property value even more.

Meanwhile if you’re feeling hot right now, visit a local park. Beat the heat among the trees.

(embedded Tweet from Jeremy Barrell; infrared heat image by Meg Caffin for the City of Geelong, Australia (Fahrenheit added); transpiring leaf from Wikimedia Commons; photos of Schenley Park by Kate St. John)