Category Archives: Mammals

Back Up So I Can Take Your Picture

Short-tailed weasel (photo from Wikimedia Commons)

6 April 2021

Clare Kines @NunavutBirder tweeted this encounter with a short-tailed weasel.

Also known as stoats or ermines, short-tailed weasels (Mustela erminea) have a circumpolar distribution. This one was filmed in Nunavut, the most northern of Canada’s Arctic territories.

See more at Clare Kines’ award-winning photography website.

(tweet by Clare Kines. photo from Wikimedia Commons)

Birds Decline, Small Mammals Thrive in a Hotter World

Cactus mouse (photo by J.N. Stuart, Creative Commons license via iNaturalist)

8 March 2021

What is the future of life on Earth as the climate warms? Which species will thrive and which decline? A study published last month in Science indicates that “in a warming world, it’s better to be a small mammal than a bird.”

In the early 1900’s Joseph Grinnell made extremely detailed records of flora and fauna in California’s Mojave Desert for the Museum of Vertebrate Zoology. A century later the average temperature in the Mojave is now 2oC (3.6oF) higher. Using Grinnell’s records a team led by Eric Riddell resurveyed Grinnell’s locations to find out how birds and mammals fare in hotter, drier conditions.

If you like birds, you won’t like the news.

[In the Mojave Desert] Over the past century, occupancy of small mammals remained stable while birds severely declined.

On average, every spot surveyed had lost more than 40% of its desert bird species, such as American kestrels or mountain quail. At most sites, even the remaining species were scarcer.

Science Magazine: In a warming world it’s better to be a small mammal than a bird.
American kestrel, 2013 (photo by Cris Hamilton)

Small mammals get around the heat problem by staying underground during the day. Birds don’t have this choice and they have an additional disadvantage — their bodies use more energy to stay cool.

It looks like there will be fewer birds in a hotter world. Read more in Science Magazine: In a warming world it’s better to be a small mammal than a bird.

p.s. There is a bird who stays underground during the day and eats small mammals in the Mojave Desert: the burrowing owl.

(cactus mouse photo by J. N. Stuart via iNaturalist (CC BY-NC-ND), American kestrel photo by Cris Hamilton)

Was The Close-up Worth It?

Striped skunk, Cokeville Meadows NWR, Wyoming, Sept 2015 (photo by K. Theule/ USFWS)

This is not my story but it’s a good one.

In September 2015 K. Theule of the US Fish and Wildlife Service was in the office at Cokeville Meadows NWR, Wyoming when she saw a skunk outside the window. She picked up her camera and …

Sometimes as a photographer, I don’t make the wisest decisions. Usually it’s a light or angle or exposure mishap. However, today my risk assessment wasn’t fully completed before I poked my head out the office door. After pressing the shutter a few times I was left wondering if the smell was going to last. But who can resist a skunk only 10 feet in front of your office door?! Just a warning to any visitors this week – the Cokeville Meadows office might stink a bit for the next few days.

description of skunk photo by K. Theule on Flickr, USFWS Mountain-Prairie

“Worth the stink? Still not sure…”

Worth the stink? Still not sure … (photo by K. Theule/ USFWS)

(photos by K. Theule/USFWS via Flickr Creative Commons license)

Raccoon Redux

Bald eagle pair scares off raccoon approaching their nest, 17 Feb 2021 (screenshot from PixCams on YouTube)

19 February 2021

On Wednesday night, 17 February just after 7pm, a raccoon scaled one of the branches that holds the Hays bald eagle nest. The mother eagle was on the nest and heard the raccoon coming so she rose up, spread her wings, and scared him away.

Seven years ago a raccoon intruder did the same thing. This one was a little braver.

The raccoon hid nearby, frozen in place, but four minutes later he moved again and the father eagle arrived to help. Two eagles!! The raccoon finally left.

This week’s episode was a raccoon redux of …

See Mary Ann Thomas’ Trib Live report, Pittsburgh Hays Bald Eagles Attack Raccoon Intruder, with video of Wednesday’s raccoon leaving.

Watch the Hays Nest Eaglecam to see what happens next.

(screenshot from PixCams on YouTube)

UPDATE, 19 Feb 2021: The female bald eagle at Hays laid her 3rd egg on 19 February 2021.

UPDATE, 22 Feb 2021: On the night of 22 Feb 2021 a great horned owl knocked the male Hays bald eagle off his roosting perch. The eagle was surprised but unharmed.

Reindeer Can See Hissing Spots On Power Lines

Reindeer in Lappland, Sweden (photo from Wikimedia Commons)

Have you ever been near a power tower whose lines are hissing? We can hear the electrical discharge but we can’t see where it’s coming from. Reindeer can see it!

You’ve probably experienced hissing power lines and wondered about the source of that noise. Sometimes the sound is so bad that it makes us worry. I remember hiking through a power line cut in Pennsylvania’s Laurel Highlands(*) where the lines were crackling. The sound was so spooky that I practically ran to the other side of that clearing!

Pylons in Briar Creek Twp, Columbia County, PA (photo from Wikimedia Commons)

The hissing is a corona discharge, the ionization of the air surrounding the high voltage conductor (wire). As electricity leaks into the air it creates hissing and crackling sounds and flashes in a spectrum we cannot see.

Since 2011 scientists have known that reindeer can see ultraviolet light. They’ve also noticed that reindeer avoid power lines by as much as 3 miles (5km). At that distance there’s no way the animals can hear the lines hissing so what is it? It’s flashing ultraviolet light!

Power companies use UV cameras to see the faults in their power lines so they can fix the leaks.

p.s. It turns out that most mammals can see some level of ultraviolet light. Humans and monkeys cannot.

(photos from Wikimedia Commons; click on the captions to see the originals. *NOTE: The tower photo shows a typical power line cut in Pennsylvania, not the one I ran across!)

Eight Tiny Reindeer?

Santa Claus at Christmas Parade, Toronto, Ontario, 2009 (photo from Wikimedia Commons)

“Twas the night before Christmas when all through the house not a creature was stirring not even a mouse.

… out on the lawn there arose such a clatter, I sprang from the bed to see what was the matter …

When what to my wondering eyes should appear, but a miniature sleigh, and eight tiny reindeer.”

excerpt from The Night Before Christmas, 1823 in The Troy Sentinel

24 December 2020

Miniature sleigh? Tiny reindeer? A human-sized Santa Claus needs a normal sleigh and full-sized reindeer to pull it. Just two reindeer take up a lot of space.

Santa in sleigh pulled by two reindeer, 2007, Torquay, UK (photo from Wikimedia Commons)

Imagine eight of these!

Reindeer to take part in Christmas festivities, Yate, UK 2004 (photo from Wikimedia Commons)

Reindeer (Rangifer tarandus), called caribou in North America, range in size from 5.3 to 7 feet long. Males weigh 350 – 400 lbs, females weigh 180 – 260 lbs. Both sexes have antlers though at different times of year.

Reindeer in Norway (photo from Wikimedia Commons)

These are not small animals. Eight full-sized reindeer and a full-sized sleigh would damage any house they landed on. Santa really needs tiny reindeer. Perhaps he went to Svalbard, a Norwegian archipelago between mainland Norway and the North Pole, to get them.

Like other island species the reindeer on Svalbard have evolved to a smaller size. If you need small reindeer they’re the smallest on Earth, only 50-60% the size of other caribou.

Problem solved.

Christmas lights, Etobicoke, Ontario (photo from Wikimedia Commons)

It’s safe for Santa to come tonight.

(photos from Wikimedia Commons; click on the captions to see the originals)

Take That!

Skunks and opossums are both nocturnal so of course they encounter each other on their nightly rambles. What do they think of each other? Do possums avoid skunks?

An encounter captured on a trail cam, tweeted by Russ McSpadden, indicates that a possum will whack a skunk if he thinks he can get away with it.

Take that, you pesky skunk!

Oh my!

(photos from Wikimedia Commons; click on the caption links to see the originals. Russ McSpadden tweet @PeccaryNotPig embedded showing Betsy Potter’s video)

Fox and Fisher

Red fox (Vulpes vulpes) and fisher (Martes pennanti) (fox by Mick Thompson on Flickr via Creative Commons license, fisher photo from Wikimedia Commons)

13 December 2020

What happens when a red fox starts to chase a fisher?

Fishers (Pekania pennanti or Martes pennanti) are fox-sized members of the weasel family, adept tree-climbers, and opportunistic hunters especially of porcupines. Uncommon in Pennsylvania, fishers disappeared because of over hunting but were reintroduced to northern Pennsylvania in 1994-1998.

Because fishers are scarce, most foxes (Vulpes vulpes) have never seen one and may mistake them for prey. That appears to happen at the start of this interaction, filmed by Becky Rowe in northern PA on 28 November 2020. Then the fox changes his mind.

By the end of their encounter it looks like they’re playing Chase Me. Fox and fisher having fun.

Thank you, Becky Rowe, for sharing this rare encounter.

(fox photo by Mick Thompson on Flickr via Creative Commons license, fisher photo from Wikimedia Commons; video from Becky Rowe on Facebook)

Giraffes and Gentoos Have Something in Common

Giraffes (southern) at Ezemvelo Nature Reserve, Gauteng, South Africa (photo from Wikimedia Commons)

What do giraffes and gentoo penguins have in common?

Though both were (or are) listed as a single species researchers say they should be four.

In 2016 DNA testing on giraffes revealed that the single species (Giraffa camelopardalis) is really four species. The proposed 2016 species split looked like this on the map …

Map of genetic subdivision in the giraffe based on mitochondrial DNA sequences (map from Wikimedia Commons)

… and is described as:

[Replace] Giraffa camelopardalis with four new ones: the southern giraffe (G. giraffa), found mainly in South Africa, Namibia and Botswana; the Masai giraffe (G. tippelskirchi) of Tanzania, Kenya and Zambia; the reticulated giraffe (G. reticulata) found mainly in Kenya, Somalia and southern Ethiopia; and the northern giraffe (G. camelopardalis), found in scattered groups in the central and eastern parts of the continent. The one remaining subspecies is the Nubian giraffe (G. camelopardalis camelopardalis) of Ethiopia and South Sudan. It is a distinct subspecies of the northern giraffe.

Scientific American, DNA Reveals Giraffes Are 4 Species–Not 1, 9 September 2016

This year a DNA study on gentoo penguins revealed that they should be split in four species, too.

Gentoo penguins (Pygoscelis papua) breed on Antarctica and islands in the southern hemisphere reaching as far as the Falklands, South Georgia and Kerguelen Island. Two populations are considered subspecies; they don’t intermingle. In 2012 the subspecies map looked like this:

Range of gentoo penguin showing subspecies as of 2012 (map from Wikimedia Commons)

The proposed split elevates both subspecies and adds two more!

The researchers suggest the two subspecies [P. p. ellsworthi and P. p. papua.] should be raised to species level and two new species created.

The four species we propose live in quite different latitudes – for example P. ellsworthi lives on the Antarctic continent whereas P. poncetii, P. taeniata, and P. papua live further north, where conditions are milder, and so it’s not that surprising that they have evolved to adapt to their different habitats.

Birdwatchers Daily, Split Gentoo Penguin into four species, researchers say, 4 Nov 2020

The split could be good news for the most vulnerable gentoo penguin populations since it would allow a focus on saving them.

Will the gentoo penguin officially split like the giraffe? We’ll have to wait and see.

(photos and maps from Wikimedia Commons; click on the captions to see the originals)

p.s. Locations of the four species as described as follows at The Conversation blog: We suggest the designation of four species of gentoo penguin: Pygoscelis papua in the Falkland Islands, P. ellsworthi in the South Shetland Islands/Western Antarctic Peninsula, P. taeniata in Iles Kerguelen, and P. poncetii, in South Georgia.