Otters II: My wildest dreams come true

Last time was mostly clues and hints. This time, pay dirt. I saw a dark shape on the far far side of my beaver pond next to a small patch of open water. Thrilled, I realized it was an otter, but then it slipped silently back into the water and under the ice. Luckily I am patient, and I waited. About 15 minutes later it popped up in a different unseen breathing hole at the base of a beaver lodge, and came all the way out.

It had a good roll in the snow, which helps to clean and dry its waterproof fur:

and I even got a short video:

Then it started to climb up the beaver lodge, behind an inconveniently placed tree,

I moved, and to my utter delight I watched it slide down the far side of the beaver lodge, just having fun. Look hard and you can just see it, near the top of the lodge behind the branches.

It went back in the water, and I thought the show was over, but 10 minutes later it returned, and had a good scratch,

and then settled down for a nap, for all the world like a dog.

The next day, on my daily walk, I assumed the otter would have moved on, but before I even reached the pond he was there, and this time closer, so I got some more photos. I like this one because you get a sense of his strength and size and sleekness, though his long tail is submerged and invisible. .

Sometime dreams do come true.

He stayed around for one more day, in the far distance, then left, but I have since seen slide marks and scat, so he is still around somewhere.

Before I started this blog, I went to the Pantanal in Brazil and had wonderful giant otter encounters, so I think next time I might dig out more of my photos from that trip and show you them in action.

PS I found some terrific clear otter tracks after my last post, so I have updated it. If you want to take a look, click January 2021 in the sidebar.

PPS You might think an otter’s feet (which lack fur) would freeze when they are diving under the ice, and sleeping on top of it for that matter. What stops this happening is counter-current circulation, explained here. It is also found in sea mammals like dolphins, and the feet of birds (like the owl from my last post).

Figure 2

Figure 2 A countercurrent heat exchange system. (a) Schematic representation. (b) Blood supply to the flipper of the dolphin, with a schematic cross-section of an artery and the surrounding veins to the left. Arterial blood is shown in red, venous blood in blue. Pink arrows denote heat flow; yellow arrows show direction of blood flow

In Figure 2a, the outgoing (i.e. arterial) blood is shown to the left, on its way to the skin surface. But en route, such vessels run very close to a network of veins that are bringing cool, venous blood back into the body (shown to the right in Figure 2a). Given the closeness of the (warm) outgoing and (cooler) incoming bloods, heat (which would otherwise be lost through the skin) is taken up by the cooler returning blood and carried back inside the animal. The red arrows in Figure 2a show the direction of heat flow; there is comparatively little heat loss from the skin. If you think about it, the system depends on outgoing and incoming blood flowing in opposite directions, which is why it is called a countercurrent heat exchanger.

From https://www.open.edu/openlearn/nature-environment/natural-history/studying-mammals-return-the-water/content-section-2.4

I dream of otters: first glimpses

[This is Act I, the preamble of a two-act otter play. Act II is the denouement, next week.]

As a child, I read Gavin Maxwell’s Ring of Bright Water, and fantasized about having my very own wild otter. Since I had never even seen an otter outside the zoo, this was not on the cards. But given half a chance, childhood passions have a way of resurfacing.

Here in Maine we have river otters, Lutra canadensis, which are 3-4 feet long, including the tail, and weigh 30 pounds. They are fairly secretive, but I see signs of them regularly along the edges of my beaver ponds, plus just once I captured a shot on my game camera. I often see scat, full of fish scales. Here are some crayfish remains from an old meal:

Until this year I had never seen them swimming around, but suddenly I had sightings:

or the back of one’s head and foot as it dived:

Now everything is frozen, and they are hunting under the ice. They may breathe in the air pocket left if the water level drops after the ice has frozen, but they also make air holes, which they revisit to keep open. Here is one on my pond this morning:

They remind me of the air-holes that seals keep clear in the Arctic. Luckily there are no polar bears in Maine keeping these air holes under surveillance.

I have stopped watching for the actual otters now winter has come, but then I saw this strange track on the snow-covered ice:

Here is my hat for scale:

The tracks followed the shoreline for perhaps 1/4 mile, and then petered out at a spot where the ice turned to open water near the dam. An otter had been heading for that open water to fish, and he had been sliding along on his belly, a favored form of locomotion in the winter. Apparently they hold their arms in, and kick themselves along with their hind legs. Here is a wonderful video of one in action (not taken by me!):

They don’t always slide: here are some more familiar tracks, on the surface of the same frozen pond, leading to a copiously used latrine (photo omitted!):

I always knew that otters would slide down river banks, but I hadn’t realized that they also go tobogganing on the flat. I would give a lot to see one actually doing it.

I have read that otters are more diurnal in the winter time, so maybe there was hope of seeing them if I returned every day? Next time, my phantom otters materialize.

PS The day after I posted this I found otter tracks on a frozen stream about a mile away, and they are lovely clear examples in thin snow on black ice of how an otter travels, so I’m adding them to this post. Here the otter is doing a bit of sliding (foreground) , and a bit of walking (background):

Here he is just walking, and dragging his tail behind:

And here is a close-up of his footprints, showing the five toes, though sadly the webbing isn’t really visible:

With thanks to Leigh for confirming this ID.

Barred Owls Redux

[I promised you mammals this time, but then I met this owl… so the mammals have to wait a week.]

On August 12 2018 I posted about Barred Owls, Strix Varia, after I found a dead one on the road. This is a happier post, with photos of a splendid and very much alive example. It was perched on the phone lines above the road, and then flew into a nearby tree and settled in. Here it is, in all its glory:

Fully grown females can weight 2 lbs. They are mainly night hunters, so this one was just trying to catch up on sleep, next to a fairly busy road. But it kept a sharp eye on the ground below, and you can see that curved beak, and the stiff whiskers that are thought to help them sense the world around them, just like a cat’s whiskers do.

The heart-shaped concave facial disc of shorter feathers helps collect and direct sound towards the owl’s ears. For more details, see the end -note.

Although the beak may look ferocious, the real weapons are the feet:

The four toes ratchet closed, clamping firmly onto a branch and allowing it to fall asleep securely, but those same talons also grip the prey like scimitars, giving little hope of escape.

Winters here are cold, and Barred Owls do not migrate down south. Sensibly, their feathers form a personal down duvet that leaves little exposed beyond the very tips of the toes. The head and neck are covered in a luxurious cowl, fully visible here when its head is turned away:

Owls can’t move their eyes, so to look around they have to move their whole head. This owl has rotated its head nearly 180 degrees, and in fact it can go even further, 270 degrees.

On the same day I saw this owl, I had signed up for a wildlife drawing class to draw… OWLS! It was clearly a sign. Here is my screenshot of a Bengal Eagle Owl, taken during the class (www.wildlifedrawing.co.uk):

and here is my drawing:

I left my real owl in peace:

Note: Wikipedia says: The concavity of the facial disc forms a circular paraboloid that collects sound waves and directs those waves towards the owl’s ears. The feathers making up this disc can be adjusted by the bird to alter the focal length of this sound collector, enabling the bird to focus at different distances and allowing it to locate prey by sound alone under snow, grass, and plant cover.

Monthly mushroom marvels

Another flashback to warmer months. Next time I return to winter, and animals.

[Disclaimer: Occasionally below I comment on edibility, but you should NEVER eat a mushroom unless you really know what you are doing. I have never eaten any of those in this post, and never will!]

We associate mushrooms mainly with the fall, but from snow-melt onwards they start to pop up.  

In April, a stunning burnt-siena-colored secondary fungus (i.e. growing on a different one underneath). It is called Pycnoporus cinnabarinus, and it was used in dying, creating a golden-brown color. In the first picture you can see how it gradually creeps over the substrate mushroom. The second picture shows a close-up.

DSC00151fungus with springtails

In May, I found this huge 4″ brain-like Conifer False Morel, Gyromitra esculenta. Notice the word ‘False’: true morels are great delicacies, and I have never found one here. Parker Veitch, who confirmed the ID for me,  says: “I’ve never tried it. I’ve read that a chef was boiling some with the lid on the pot and when he took it off he inhaled the fumes (monomethylhydrazine – same stuff as in rocket fuel) and died. My mentor also told me that it’s rated the 6th best edible in Europe.” My mushroom book simply says it is “deadly”. I did NOT try it.

DSC05740

In June, minuscule 2mm sunny saffron-yellow jelly fungi, Dacrymyces capitatus, sprouted on a piece of dead wood:

In July, the Russulas start to appear. This Tacky Green Russula, Russula aeruginea, is a rather implausible green color, suggestive of chlorophyll, but fungi lack chlorophyll and do not photosynthesize. The Latin name refers to the green patina that copper acquires over time. Maybe there is a copper compound in these fungi, I not been able to discover the answer. It is supposedly edible, but somehow I find its green color extremely off-putting, and have never tried it.

By August, some of the more familiar autumnal mushrooms start to appear. This is a Shingled Hedgehog, also called a Scaly Tooth, Hydnum imbricatum, which David Arora accurately describes as looking like a “charred macaroon”.

September brings out some of the more dramatic tree fungi, This is a Comb Hericium, Hericium ramosum:

And in October, I found a Ravenel’s Stinkhorn, Phallus ravanelii, past its smelly best, but still unusual looking. It was about 6″ tall, with a white ring at the top.

and it grew out of a little cup at its base:

When I turned it inside out, the interior of the cap had a mesh just like tripe:

The spores are contained in a smelly green slime that coats the outside of the cap, and attracts flies. The spores then stick to the fly, which helpfully disseminates them. Eventually the slime washes off the outside of the cap, leaving the mushroom as you see it here.

Off to a dinner of nice safe supermarket shiitakes.

Woodpecker in action

[2021 is upon us and let us all hope it will be better than 2020. Thankyou for reading my blog, and I hope it brings a small sense of the vastness of nature into your circumscribed world.]

Have you ever watched a woodpecker feeding? This is a Hairy Woodpecker, checking for danger before starting his onslaught:

He braces himself, using his tail to help:

And then he starts to hammer away. This video was taken on a different occasion in the same corner of my woods, so it may be the same woodpecker:

He goes at it so hard that his head blurs on camera, and you actually see the wood chips on his white breast:

He is looking for beetles, ants or grubs, and once he has made a suitable hole he sticks his beak and his very long tongue deep into the (probably hollow) tree:

And if he has done a good job, he is rewarded with a juicy grub:

Down it goes:

Why doesn’t he get concussion, or at least a headache? Turns out there are several adaptations that help, detailed in an endnote below.* One of the cleverest ones is a highly specialized hyoid bone (in humans, it is a teensy little bone at the base of the tongue.) In woodpeckers, it is vastly elongated, and it splits in two, goes on each side of the spine, winds around the back of the head and in through the right nostril to form a sort of sling affair, acting as a safety belt. Here is a picture:

It has even been suggested that this would make a good model for a prototype crash helmet (May et al 1976). The biomechanics of how woodpeckers survive bashing away at up to 12,000 strikes a day at a speed of around 7 meters/sec have been studied in great detail:

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0026490

* Wikipedia gives this summary of their adaptations: “To prevent brain damage  from the rapid and repeated powerful impacts, woodpeckers have a number of physical features which protect the brain. These include a relatively small and smooth brain, narrow subdural space, little cerebrospinal fluid (CSF) surrounding it to prevent it from moving back and forth inside the skull during pecking, the orientation of the brain within the skull (which maximises the contact area between the brain and the skull) and the short duration of contact. The skull consists of strong but compressible sponge-like bone which is most concentrated in the forehead and the back of the skull.”