More Winter Adaptations

The dead of winter is nigh upon us. It had been relatively mild where I am, despite a colder fall than usual. Unlike this time last year, we are having some temperatures above freezing. I deal with the cold by putting on this flannel,

but how are some more of out animal friends coping?
The wood frog survives by going into suspended animation while buried in mud or leaf litter. For all intents and purposes, it is dead. It survives the cold (and insect-free) winter because it produces a natural antifreeze that keep the water in its cells from freezing and bursting.

Wood frog (MN Dept. of Natural Resources)

Deciduous trees also have to work around internal ice causing cells to burst. In late summer they prepare for winter by shedding their leaves, which reduces the surface area that snow and ice can accumulate on. That protects branches from breaking. They also drastically reduce water consumption. It won't be needed without photosynthesis happening, and less water stores in the trunk is less risk of water freezing and causing a rupture.

Leafless trees that gave up drinking

Snapping turtles survive by spending the winter underwater. Lucky for them, water freezes from the top down rather than from the bottom up. The cold water and lack of oxygen may seem less than ideal living conditions but somehow the turtles survive by changing their blood chemistry to compensate for increasing levels of acid.

Snapping Turtle (Missouri Dept. of Conservation)

Insects also are able to adapt to winter conditions. I always assumed they flew south ahead of the birds or just did when I was younger. Some use the same antifreeze method as the wood frog. Others allow themselves to freeze without becoming ice, a process known as supercooling. Supercooled fluids remain liquid at temperatures below freezing. But the risk is always there that a single particle could allow ice crystals to form. Once that happens it's game over.  The fluid instantly iced over, killing the insect.

Supercooled stonefly (Scientific American)

While you are enjoying the snow from inside your cozy house, just be thankful you don't have to rely on chemistry or dehydration to make it through the winter. And next time you need a snack, it probably won't be your last for a few months.
This week's information comes from the Minnesota Department of Natural Resources and Bernd Heinrich's book "Winter World".

Wisdom of the Ages

While it’s cold and snowy where you are, it’s a warm sunny day on the Pacific atoll of Midway Island, where mating season just ended for the Laysan albatross. Most famous of these large seabirds is Wisdom, the oldest known wild bird. She’s at least 67 years old and still laying eggs. Being that old and still raising young makes me wonder just how long these birds can last.

Wisdom’s age was discovered in 2002 when her band was replaced. The biologist who replaced her band looked up her number and noticed that he originally banded her in 1956, and at that time she was an adult of at least 5 years old.

Wisdom (right) and her mate during nesting season (USFWS)

What is remarkable about this particular bird so special, at least to me, is that she managed to survive so many threats in her time, beyond the normal dangers like predators, disease, and typhoons. Working in her favor are the Migratory Bird Treaty and the US Wildlife Refuge System, protecting her and her kind from human predation and habitat loss at their nesting sites on Midway.

Working against Wisdom and other albatrosses are a whole host of man-made problems. Foremost among them is ocean plastic. Laysan albatrosses feed at night, and their food is fish, squid, and fish eggs that come near the surface. Sadly, floating garbage is also at the surface. In a tragic sequence of events common to marine life everywhere, they mistake plastic for food and either eat it themselves or feed it to their chicks. Despite having full stomachs, the birds and other critters die of starvation because plastic is not very nutritious.

Invasive species are also beginning to take a toll on the albatrosses. They have already been extirpated from the Hawaiian Islands, outcompeted or outright killed by the dogs, cats, pigs, and rats that accompanied Europeans as they traversed the Pacific. Now, the Midway colony is under attack by mice. While the birds are much larger than the mice, they succumb to bite wounds rather move to a mouse-free area because of their dedication to their eggs. US Fish and Wildlife Service is working on eradicating mice from Midway, but having lived with them for thousands of years I think we all know how well that will work out.

Mouse attack victim (Audubon)

This week's information comes from the US Fish and Wildlife Service and the National Audubon Society 

Nature Minute Book Club

While it's not as cold as it was this time last year, I'm still hunkered down for winter. Even though temperatures are more seasonable this year, it's still a good time to curl up with a good book. Here are a few I read in the last year.

The Soul of an Octopus by Sy Montgomery

Naturalist Montgomery spent time at the New England Aquarium in Boston, where she got to know the aquarists and their charges. Getting up close and personal with the octopus (several over the course of a few years). In that time, we explore animal personalities and intelligence. As the aquarium loses and acquires new octopuses we learn about their life cycles. Overall, the book does a good job of breaking down the stigma against this odd-looking mollusk.

The Gulf by Jack E. Davis

Part history, part geology, part ethnography, and part ecology, this book examines every facet of the Gulf of Mexico. Beginning with the Gulf’s prehistoric origins to its modern day exploitation and ecological disasters, Davis shares his intimate knowledge of what he terms “the American Sea”. Meet some of the colorful characters who shaped Gulf culture as we know it today: from Colusa chieftains to Spanish conquistadors to tarpon fishermen, oil barons, feather hunters, and conservationists.

What a Fish Knows by Jonathan Balcombe

Balcombe dives into what makes a fish different from a mammal or a bird, and what is surprisingly similar. Anecdotal evidence, mixed with lab and field research reveals much about a fish’s sensory and perception, emotion, thought, communication, intelligence, and farts.

Rain: A Natural and Cultural History by Cynthia Barnett

For centuries, mankind has had a love-hate relationship with rain. We curse it for ruining our picnics and parades. We suffer from not enough or too much. Take a journey through time and see how our understanding of rain has changed over the years and how rain (or lack of it) has shaped the course of history and influenced pop culture.

Furry Logic by Matin Durrani and Liz Kalaugher

This book takes place at the intersection of biology and physics, exploring how animals of all shapes and sizes use physics in their daily lives. Learn about how snakes and ground squirrels use thermodynamics; see Komodo dragons and shrimp use force. Marvel as bees defy our understanding of aerodynamics, elephants communicate through seismic waves, and ants find their way home with polarized light. The section on eels will shock you!

Species of the Month

Up on the rooftop click click click, down through the chimney it's the species of the month! Christmas is right around the corner, so it’s time for another festive species of the month. The caribou is the wild version of the domesticated reindeer. Santa’s herd is safe, but their wild counterparts face habitat loss and in some areas have been hunted to extinction.

Woodland caribou

Scientific name: Rangifer tarandus

Kingdom: Animalia (animals)

Class: Mammalia (mammals)

Order: Artiodactyla (even-toed ungulates)

Range: Circumpolar- Canada, northwestern US, Greenland, northern Europe

Habitat: Arctic tundra and boreal forest

Lifespan: 4.5 years on average

Diet: Leaves, bark, lichen, mushrooms

Predators: Bears and wolves

Conservation Status: Endangered (US), IUCN Species of Least Concern

Lighter colored tundra caribou (NPS)

Other Information: Caribou are the only deer species featuring antlered females. Not all females grow antlers, however. Male antlers are larger and more intricate. Males use theirs in sparring during the rut. Like other deer species, mating is controlled by a dominant bull who fends of younger challengers. The fights leave males injured and/or exhausted and vulnerable to predators. Domesticated reindeer have been used as beasts of burden and for food for thousands of years. There are several subspecies of caribou. Northern caribou are nearly white and smaller than their southern counterparts. In North America, the woodland caribou is a dark brown and critically endangered. Just a handful lived in the wild in Washington and Idaho. Recently, they were all captured and sent to a secure area in British Columbia to protect them from predators in the hopes that their population will increase. Caribou hooves are very large and concave, serving as snowshoes.

Caribou hoof (Where To Next)

The size and shape also aid in swimming. Caribou migrate long distances and must cross many rivers. When walking, they make a loud clicking sound, caused by a foot tendon rubbing on bone.

Information once again comes from the good people at Michigan’s AnimalDiversity Web.

Domestic reindeer (The Nature Conservancy)

A Christmas Comet

Just in time for the holidays Earth has a celestial visitor! Comet Wirtanen makes one of the closest approaches ever recorded. It’s a small comet with a short orbital period of 5-6 years. It is bright enough to see with the naked eye, although because of its small size the way it scatters light, it is hard to spot. Keeping with the holiday tradition, if you’re lucky enough to see it, it will appear to be green.

Wirtanen approaches, as seen in November (NASA)

I am sadly surrounded by street lights, so I had to take a short trip to a state park where I had a dark sky. With a spotting scope and a general area of where to look, I was unable to find Wirtanen. The comet makes its closest approach to the sun tonight, and I decided to try again. However, I’ve been blessed with clouds. My next chance is Saturday night, when it is closest to Earth. Of course, rain is in the forecast.

Geminids (Smithsonian Magazine)

While I failed in my attempt to see just my second comet, I happened to see a meteor streak across the sky. Meteor showers are bits of cometary debris burning up in the atmosphere as Earth passes through the comet’s debris field. Comets are just dirty snowballs that melt a little bit as they approach the sun. As they break up, all the pieces that break off trail behind and wait for our orbit to sweep them up. This meteor was not associated with Wirtanen. It was part of the Geminid meteor shower, which is debris from the comet 3200 Phaethon, a dead comet. Its ice has melted and all that remains is rock. Most likely, if we ever pick up all the debris then there will be no more Geminids.

If you want to try your luck at finding Wirtanen, here’s a handy link that shows its location throughout the month. This month's information is from StarDate and NASA.