Bear scat, Sugar Run Trail, Ohiopyle State Park, 19 May 2016 (photo by Kate St. John)
Last month I hiked the well traveled Sugar Run Trail at Ohiopyle State Park. At the top of the trail I saw footprints of people and dogs … and I encountered this. I put my boot next to it for scale.
I didn’t see paw prints near it but the size of this scat pile indicates it was deposited by a large mammal. There’s not a lot of fur in it and it’s blue (why?) so this animal eats more than just meat.
The scat had been deposited so recently that I could smell it as I took the photograph. I found another, older pile further down the trail. This large omnivorous mammal left his mark over and over again. A black bear.
The bear lives there. I was just visiting. Though he wasn’t in sight he was probably in earshot so I made human noise (speaking, whistling) so he’d know I was traveling through.
I’m sure he didn’t want to be surprised any more than I did!
Solenodons are nocturnal mammals that look like large, big-footed shrews. They eat beetles, crickets, worms, snails and even birds and reptiles which they paralyze with a bite containing their venomous saliva. Interestingly, solenodons aren’t immune to each others’ venom so if they fight they succumb when scratched by the teeth of a combatant. (The Hispaniola solenodon is so poorly studied that we’re not even sure if it fights very often.)
These mammals evolved in the absence of predators so they are slow, clumsy runners and tend to trip and fall when pursued. They are now so rare and so endangered that they’re expected to go extinct in the next 10-20 years because of habitat loss and predation by dogs, cats and humans.
With time running out for this animal, scientists wanted to sequence its DNA before it disappeared, and they had to catch it in a manner that was safe for the animal and for them. But how?
p.s. Did you know there’s a venomous mammal in Pennsylvania? The northern short-tailed shrew has venomous saliva that paralyzes its small prey. From Joseph Merritt’s Guide to the Mammals of Pennsylvania, “When humans are bitten, they may experience considerable irritation and swelling that could last up to three days.” Predators, including house cats, don’t eat this shrew because it smells so bad.
top photo by Taras Oleksyk and Yashira Afanador of ZooDom veterinarian Adrell Nunez with solenodon.
photo of Hispaniola solenodon by Miguel A. Landestoy, linked from The Mantis Shrimp blog)
May is the month when one-year-old bears are on the road, searching for a first home since mama pushed them out this spring.
If you live in the country you’ve already noticed the bears are active and had to pull in your bird feeders so the bears don’t wreck them. If you live in the city or suburbs you might not realize that bears are possible in your area … until one shows up.
When you see a bear don’t make the mistake of feeding him. He’ll think People=Food and continue to hang around, ransacking the neighborhood.
No. He could eat them if he wanted to but these barbell fish are his helpers. They eat ticks from his skin and food from his teeth. It’s a symbiotic relationship.
The hippo and the barbell fish are just one example of the unlikely partnerships animals make with other species. Watch the premiere of Nature’s Perfect Partners on Wednesday May 11 to learn about many more — lizards with lions, a fish with a blind shrimp, toads with tarantulas.
Tomorrow is the mid-point of winter, halfway between the winter solstice and the vernal equinox. February 2 is also the day when a very special rodent, Punxsutawney Phil, emerges from his den to predict the weather for the next six weeks.
Phil never makes his prediction in isolation. His day in the sun (or shade) spawns a huge celebration in Punxsutawney, PA. Preview the excitement in his eight minute promo video above.
If you don’t like winter, then hope for an overcast sky so that Phil has a day in the shade. Here’s why.
Did you know there’s a whale with a horn like a unicorn?
The narhwal (Monodon monoceros) is an arctic whale, closely related to the beluga whom it resembles.
Close relatives: Beluga whale and narwhal (illustration from Wikimedia Commons)
Like the beluga, it has teeth though it doesn’t use them for chewing. All but two of the teeth are vestigial but one of those, the left canine, grows though the male’s upper lip spiraling counter-clockwise, straight out, in a single tusk as much as nine feet long.
The tusk is not a sword. Instead, like our teeth it’s made up of layers but it’s hollow inside and much more sensitive. The outer layer is permeable, allowing seawater to pass through the dentin into the hollow core filled with millions of nerves. Scientists know the tusks can sense salinity but they probably can sense a lot more. When narwhals surface to breathe and rub tusk to tusk they’re not fighting, they’re communicating.
Narwhals are so specialized it may lead to their extinction. They live only in the Arctic Ocean where they depend on its icy habitat for food and shelter. They roam in pods of 5-10 individuals and may migrate in groups of 1,000 but they seem more loyal to their favorite sites than to following their food. As climate change heats the water and melts the arctic ice, narwhals will have less food and fewer places to live. Like the polar bear, narwhals are threatened by climate change.
If or when this whale goes extinct it may pass into mythology, like the unicorn.
Unicorn in the Book of the properties of Bartholomew the Englishman, early fifteenth century (illustration from Wikimedia Commons)
(photos from Wikimedia Commons. Click on the images to see the originals)
Semi-aquatic, vegetarian, and closely related to the guinea pig, capybaras swim a lot. They eat grass and aquatic plants which fortunately wear down their continuously growing teeth. They also eat their own feces to get more nutrition out of their partially digested food.
Capybaras are big. They stand as tall as a German shepherd but of course they’re not the same shape and they weigh a lot more. For a sense of scale, here’s a group of capybaras grazing in a park in Brazil.
Capybaras grazing at Parque Barigüi, Curitiba, Brazil (photo from Wikimedia Commons)
These groups are typical. Capybaras are very social and live with 10-20 and up to 100 other individuals. The round bump on their snouts is a scent gland called a morillo which they rub on everything to say “I’m here.” They also use anal scent glands and urine for the same purpose. Obviously capybaras do not make good pets.
As for the bird, why is the caracara on the capybara?
More on that tomorrow.
(photos from Wikimedia Commons. Click on the images to see the originals.)
(*) Both the bird and the mammal have increased their range into southern Central America.
Are humans the only species that fools others to survive, find food, and mate? Not at all!
This month PBS NATURE premieres a new three-part series, Natural Born Hustlers, airing on PBS on Wednesdays, January 13, 20 and 27 at 8:00pm (ET) (check local listings).
Episode One, Staying Alive, focuses on survival techniques: camouflage, dominance tricks, audio mimics and playing dead. Early on I was amazed to learn how zebras’ stripes create an optical illusion. You have to see them in motion to believe it!
Other fascinating finds are the amazing skin-morphing camouflage of cuttlefish, the lizard that walks like a stinky beetle, and the white-faced capuchin monkeys who calculate whether they’re needed in battle. “More capuchins are killed by their own kind than by predators,” says the episode. What an unfortunate trait to have in common with humans.
The video excerpt above gives you a good idea of animals’ ingenuity. California ground squirrels use their enemy’s scent as protective camouflage. Their arch enemy is the rattlesnake, so if you hate to look at snakes this video will make you flinch.
And fair warning to those afraid of snakes: Staying Alive has quite a few snakes in it including a match-up in North Carolina of a harmless species that mimics the coral snake. The bonus is that you can identify birds by song on the audio track.