Category Archives: Mammals

Fewer Deer, Less Garlic Mustard

Deer and garlic mustard (deer photo from Wikimedia Commons, garlic mustard photo by Kate St.John)
Deer and garlic mustard (deer photo from Wikimedia Commons, garlic mustard photo by Kate St.John)

 

If you like native plants you're probably dismayed by the increase of invasive garlic mustard (Alliaria petiolata) in Pennsylvania's woods.

Garlic mustard has become more abundant at the same time that Pennsylvania's deer population has exploded.  Since deer don't eat garlic mustard, observers assumed the plant's increase was directly tied to the fact that deer eat natives and not this invasive alien.

But the relationship is more complicated than that.

At October's meeting of the Botanical Society of Western Pennsylvania, Dr. J. Mason Heberling presented conclusions he's drawn after studying the interaction of garlic mustard, native plants, and deer from a 13 year experiment at Fox Chapel’s Trillium Trail.

It turns out that garlic mustard likes more sun than it normally gets in Pennsylvania's summer woods so when deer over browse native plants their shade goes away and garlic mustard thrives.

When deer are excluded native plants grow again, they shade the garlic mustard and it decreases.

Fewer deer?  Less garlic mustard!

Everything is connected, often in amazing ways.

 

For more information, read the study abstract here at Interactions of White-tailed Deer and Invasive Plants in Forests of Eastern North America presented at the Botany 2016 Conference.

(photo of garlic mustard by Kate St. John. photo of deer by josephamaker2018 via Wikimedia Commons; click on the original)

Funny Face is Flehmen Response

If you have a cat, I'm sure you've seen it sniff something and then raise its head with its mouth open as shown in the video above.

This gesture is called the flehmen response or flehmening and it's how cats inhale and analyze pheromones.

Many mammals flehmen in response to pheromone laden scents. They bare their teeth, close their nostrils and breathe through their mouths to direct the scent into the vomeronasal organ (VNO) located above the roof of the mouth.  In felines, there's a duct just behind their front teeth that leads to the VNO.

Horses flehmen, too.  When I was a kid there was a TV show called Mister Ed, the Talking Horse, whose face looked like this when he "talked."

Flehmen response of a horse (photo from Wikimedia Commons)
Flehmen response of a horse (photo from Wikimedia Commons)

Now that I've seen this photo, I'll bet the trainers put an interesting smell under Mister Ed's nose to provoke the flehmen response.  And they said he was "talking."

 

(video by Kyle Hayes on YouTube. photo of horse flehmen response from Wikimedia Commons; click on the image to see the original)

Cars And Deer

Deer spooked near the road (photo by Mike Tewkesbury, Creative Commons license via Flickr)
Deer spooked near the road (photo by Mike Tewkesbury, Creative Commons license via Flickr)

It's that time of year again when cars and deer come into conflict.

From October through December white-tailed deer hormones surge for the mating season.  Males become aggressive, spar with their rivals, and challenge anything they see as a threat.  Both sexes roam in search of mates and barely pay attention to their surroundings.  Cars are the last thing on their minds.

Last year, Pennsylvania won the "prize" for the most deer-vehicle collisions in the U.S.   According to a September 2015 article by Ad Crable at Lancaster Online, we hit 127,275 deer with our cars -- and those were only the collisions reported to insurance.   When compared to hunting season, which took more than 353,000 deer that year, we're making a sizable dent with our vehicles.

A case in point is in Schenley Park where hunting is prohibited, as in all Pittsburgh City Parks.  Deer used to be rare but they moved in about 10 years ago (perhaps longer) and their population has exploded in the past five years.  I knew we'd reached a milestone when I saw a first ever road-killed deer in the Park along the Boulevard of the Allies, hit on November 5 or 6.

I'm sure the person who hit that 6-point buck was very, very surprised.  So are those whose dogs are challenged by aggressive deer.  Every year since 2015, a buck has killed a dog in the City's east end parks.

So be careful out there, especially at dusk and dawn when deer are most active.  Use your brightest headlights and slow down.  Don't become a statistic.

 

Reminder: Deer (rifle) season begins tomorrow, Monday November 28, in Pennsylvania. Wear blaze orange when you're outside the city.

(photo by Mike Tewkesbury, Creative Commons license via Flickr. Click on the image to see the original.)

Putting On His Winter Coat

Long-tailed weasel, Calgary, Alberta, 30 Oct 2016 (photo by Dan Arndt)
Long-tailed weasel, Calgary, Alberta, 30 Oct 2016 (photo by Dan Arndt)

Oh my!  It's a white weasel in a brown background.

Long-tailed weasels (Mustela frenata), native from Canada to South America, molt twice a year in October-to-mid-November and March-to-April.  Those who live in the north turn white, the rest of them stay brown.  Here's what they look like in summer.

On October 30 in Calgary, Alberta, Dan Arndt easily found this long-tailed weasel checking out the scenery near Fish Creek Provincial Park.  The weasel had turned mostly white though his back was still pale brown (see below).

Long-tailed weasel, Calgary, Alberta, 30 Oct 2016 (photo by Dan Arndt)
Long-tailed weasel, Calgary, Alberta, 30 Oct 2016 (photo by Dan Arndt)

Long-tailed weasels are fearless and aggressive, able to kill animals larger than they are, but they're small enough to fall prey to large mammals, hawks and owls(*).  Camouflage is important.  Their fur is meant to hide them as they hunt and are hunted.

This weasel turned white right on time but there's no snow to hide him.  The first frost usually occurs in Calgary on September 16 and it snows 3.9" (10cm) in October, but not this year.  The high was 54oF (12.2oC) on the day these pictures were taken.

Long-tailed weasel, Calgary, Alberta, 30 Oct 2016 (photo by Dan Arndt)
Long-tailed weasel, Calgary, Alberta, 30 Oct 2016 (photo by Dan Arndt)

 

It's likely that climate change will change northern long-tailed weasels.  They'll probably still molt in October-to-mid-November but without snow to hide them the whitest ones won't survive.  I expect the population will be browner in Canada a century from now.

Long-tailed weasel, Calgary, Alberta, 30 Oct 2016 (photo by Dan Arndt)
Who are you looking at? (photo by Dan Arndt)

In the meantime, this one looks annoyed that he's attracted attention now that he's put on his winter coat.

 

(photos by Dan Arndt)

(*) Long-tailed weasels are 12-14" long but their tails make up 40-70% of their length.  Thus their bodies are only 4-8" long.

It’s Bat Week!

In case you haven't heard it's international Bat Week.

This week, October 24-31, we celebrate furry flying mammals, learn about their benefits to mankind, and help them survive in our ever changing world.

Did you know these cool facts about bats?

  • There are more than 1,300 species of bats on earth, 40 in the U.S.
  • Bat wings are webs of skin between their fingers (forelimbs).  Bats have more bones in their wings than birds do.
  • Bats have "thumbs" on the leading end of their wings that help them grasp and climb. The tropical Spix’s Disk-winged Bat roosts on leaves so he has suction cups where his thumbs would be.  Click here to see.
  • According to batcon.org, some male bats sing like songbirds to defend territory and attract mates.
  • Most bats reproduce very slowly, only one pup per year.
  • An amazing number of bat species are threatened with extinction -- even some that live in Pennsylvania.

Watch the video above to see Rodrigues fruit bats (they're Critically Endangered) then stop by the National Aviary in Pittsburgh to see the Megabats shown below -- Malayan Flying Foxes.

Malayan Flying Fox fruit bat being fed (photo by Denmarsh Photogtaphy courtesy the National Aviary)
Malayan Flying Fox fruit bat being fed (photo by Denmarsh Photography courtesy the National Aviary)

 

Happy Bat Week!

Malayan Flying Fox fruit bat, resting upside down (photo by Denmarsh Photogaphy courtesy of the National Aviary)
Malayan Flying Fox fruit bats at the National Aviary (photo by Denmarsh Photography)

 

Learn more about bats at Bat Conservation International.

(video from the San Diego Zoo, photos by Denmarsh Photography courtesy of the National Aviary)

Anniversary of The Fox

Red fox crossing a street in Portugal (photo from Wikimedia Commons)
Red fox in Denver neighborhood (photo from Wikimedia Commons)

In autumn young animals leave their birthplace to find a home of their own.  Sometimes they wander into dangerous places -- roads, for instance -- and sometimes they surprise us.

Seven years ago this month a red fox wandered into my Pittsburgh city neighborhood and spent a couple of weeks in the block near my house.  Our first hint of her presence was the sound of her voice.

On this Anniversary of The Fox, read more about her visit at:

Mystery Solved

 

p.s. I'm only guessing she was female.  There's no way to know.

(photo of a fox crossing a street in Denver, Colorado from Wikimedia Commons. Click on the image to see the original)

Prevent Lyme Disease In Your Own Backyard

White-footed mouse raiding the peanut feeder at night (photo by Rob Ireton, Creative Commons license on Flickr)
White-footed mouse raiding a backyard peanut feeder at night (photo by Rob Ireton, Creative Commons license on Flickr)

If you live in a Lyme disease area and feed the birds, you might get Lyme disease in your own backyard.  Here's what makes that possible and how you can make your yard safe.

When you provide food for birds, a lot of other animals eat that food as well.  Squirrels and chipmunks eat during the day.  The mice come at night, especially white-footed mice pictured above at a peanut feeder.

Animals live close to their food sources so they live in your backyard or even your house. Here's a favorite mouse and chipmunk home -- the nooks and crannies of stone walls.

Stone wall (located in Vermont, photo from Wikimedia Commons)
Stone wall (photo from Wikimedia Commons)

 

The abundance of birds and rodents in your yard attracts predators: hawks, owls, cats and even ticks. You'll see the big predators but you might not notice the tiny ones.  Adult black-footed ticks are very hungry in October and November so watch out.

Chart of black-legged tick life stages (image from Wikimedia Commons)

Birdseed --> mice --> ticks -->  Lyme disease.  White-footed mice are reservoirs for Lyme disease so the black-footed ticks that feed on your backyard mice may be infected.

What to do?

It's impossible to get rid of all the mice -- even if you stop feeding the birds -- but you can get rid of ticks, and that's what counts in the battle against Lyme disease.

The mice will help you do it.  Mice like soft fluffy bedding in their nests and will carry it into their secret hiding places.  If you give them anti-tick bedding it kills the ticks on them and in their nests.

This ingenious defense is described here at TickEncounter.org.  In their photo below, a mouse is gathering anti-tick bedding -- permethrin-sprayed cottonballs -- from the blue-green tube.

White-footed mouse with anti-tick tube and cottonball bedding (photo from tickencounter.org)
White-footed mouse with anti-tick tube and cottonball bedding (photo from tickencounter.org)

You can make your own tubes (cottonballs, paper tubes, Permethrin) or buy them complete with instructions at ticktubes.com.  Be sure to read about this technique at Tick Encounter before you begin.  And then ...

No more ticks!

 

p.s. You'll see at Tick Encounter that July and August are the optimal time for setting out Tick Tubes.  Sorry my timing is off.

p.s. Be sure to read the comments about Permethrin hazards. It is very bad for pets!

(photo credits: Click on the images to see the originals in context
White-footed mouse at night by Rob Ireton, Creative Commons license on Flickr,
Stone wall photo from Wikimedia Commons,
Chart of black-legged tick life stages from Wikimedia Commons,
White-footed mouse with anti-tick tube and cottonball bedding from tickencounter.org
)

Why Are We Thirsty Before We Sleep?

Glass of water (photo by Kate St.John)
Tall glass of water (photo by Kate St.John)

Have you noticed that you're thirsty before you go to sleep?  Why is that?

A recent study published in the journal Nature might not provide the answer for humans but it feels right to me.

Researchers at McGill University noticed that two hours before they went to sleep mice drank more water than they actually needed.  The scientists restricted access to water before bedtime and the mice became dehydrated while they slept.  Obviously drinking water ahead of time is a survival mechanism.

But how did the mice know to drink so much?  Using ingenious tests the research team found that the animal's biological clock was sending a "drink water" signal to the brain's thirst center.

I'll bet this is true of humans, too.  My biological clocks says, "Drink water" and so I do.

Read more about the study here in Science Daily.

 

(photo by Kate St. John)

A Visit to Elk Country

Bull elk grazing in a front yard in Elk County, 4 Oct 2016 (photo by Kate St.John)
Bull elk grazing in a front yard in Elk County, Pennsylvania, 4 Oct 2016 (photo by Kate St.John)

Last Tuesday Geralyn Pundzak, Kathy Miller and I made a one day trip to see the elk near Benezette, PA.  During the rut, September-October, the males pursue the ladies, spar with other males and “sing” a bugling love song.

Our first two stops came up empty and we began to worry that we'd miss them.  Geralyn, who drove us there, said she wouldn't leave until she saw an elk. The pressure was on!

At Woodring Farm we heard an elk bugling on the hill above us.  He soon crossed the gravel road only 100 yards away, then stopped to bugle among the trees.  I was so excited I forgot to take pictures.

On our way to Dents Run we saw an elk lying down, almost on a front porch. Was he a statue?  No, his head moved!  We returned to an elk traffic jam and took these photos.

Bull elk in Elk Country, 4 Oct 2016 (photo by Kate St. John)
Bull elk in Elk Country, 4 Oct 2016 (photo by Kate St. John)

Bull elk grazing in a front yard, 4 Oct 2016 (photo by Kate St. John)
Bull elk grazing in a front yard, 4 Oct 2016 (photo by Kate St. John)

Bull elk in Elk Country, Pennsylvania, 4Oct 2016 (photo by Kate St. John)
Bull elk in Elk Country, Pennsylvania, 4 Oct 2016 (photo by Kate St. John)

In addition to the elk we enjoyed birding, scenic overlooks, and the Field of Flowers at Woodring Farm.

A view of Elk County from Woodring Farm overlook (photo by Kate St. John)
Elk County view from Woodring Farm overlook (photo by Kate St. John)

.

At the Field of Flowers, Woodring Farm, Elk County, PA, 4 Oct 2016 (photo by Kate St.John)
At the Field of Flowers, Woodring Farm, Elk County, PA, 4 Oct 2016 (photo by Kate St.John)

Visit Elk Country now while the elk are bugling and the leaves are changing.

 

(photos by Kate St. John)