Glossary of Terms

Here at Nature minute, we use a lot of big words, or even just smaller words you've probably never heard before. It's a fine line between going over your head with technical terms and dumbing it down too much. In the interest of walking that line, here are some of the words you might hear thrown around the office or in the field.

Alluvium- eroded sediments, deposited on land by water. Areas are sometimes referred to as "alluvial plains"; these are where the soil is made up of mostly alluvium.
Benthic- the bottom of a body of water. A river bed and the sea floor are benthic zones, or benthos. Benthic also refers to the organisms living in the benthos.

These insect larvae are benthic creatures

Brumation- a state of lowered metabolic activity in cold-blooded animals; it is similar to hibernation.
Crepuscular- active around dawn and dusk. Deer are crepuscular mammals.

Deer being crepuscular in my back yard, circa 2015

Epiphyte- plants which grow on other plants, but are not parasitic. In the Pacific Northwest, ferns often grown in trees.

Epiphytic ferns

Ephemeral- seasonal. During the spring melt, ephemeral streams and waterfalls form in the mountains.

Ephemeral waterfall cascading down a hillside

Fossorial- digging species which live mainly underground. Moles and badgers are fossorial mammals.
Hadal- the deepest oceanic zone. Deep sea trenches are the hadal zone.
Littoral- the nearshore zone of a body of water, from the high tide line to the shoreline.

This horseshoe crab is in the littoral zone

Torpor- a state of lowered metabolic activity and body temperature in warm-blooded animals. Like brumation, it is similar to hibernation.
Transpiration- water exhalation by a plant. Water is lost as vapor through pores in the leaves.
Ungulate- mammals with a hoof. They come in 2 orders: Artiodactyla, which have an even number of toes, and Perissodactyla, which have an odd number of toes. Those crepuscular deer are ungulates.

Be Bear Aware

With the arrival of fall and the approach of winter, food sources are becoming scarce for some animals. Bears spend the winter either hibernating or in torpor, a state of lowered metabolic and other bodily activities. To prepare, they begin gorging themselves this time of year so they can have enough calories to last through an extended period of not eating. While they generally try to avoid humans, now and when they emerge in spring (very hungry) are the most likely times you will encounter a bear. Here are some helpful tips on how to avoid or survive a bear encounter.

Don't let this happen to you! (US Forest Service)

Hungry bears are attracted to food and will follow their noses. When camping, store food, drinks, utensils, cookware, dishes, cosmetics, and hygiene products in a bearproof container, locked in a vehicle, or suspended 10-15 feet above ground and 4 feet on all sides from a climbable surface. Sleep in a tent or camper away from your cooking area. Don't sleep in clothes you cooked in. Don't set up camp near berry patches, carcasses, and bear signs. Avoid foods with a strong smell like bacon and fish, no matter how good they are. Sleep near your flashlight and bear spray. If you see a bear try scaring it away by making loud noises. If it is undeterred, move away to a safe area.

Ideal camp setup (WildAware Utah)

When hiking, if you see a bear that hasn't noticed you, move away quickly, quietly, and calmly. Never try to run from a bear. Running might trigger the chase instinct and the bear will always beat you in a race. If you see a bear and it notices you, let it know that you are human and  not food or another bear. Talk to it calmly, move your arms about, and keep an eye on it without making eye contact. Hopefully the bear will leave. If it does, walk away in a different direction. If it remains, back away slowly but keep making small talk. If the bear approaches you and is acting defensively- making loud noises moving its head around, or stomping or pawing at the ground, stand your ground. If the bear approaches, it's probably bluffing. Keep talking calmly to it, and start backing away when it stops coming at you. If it comes at you again, stop moving but keep talking until it stops again. If it attacks you, now is the time to play dead. Face down on the ground, keep your backpack on if you have one. If the bear rolls you over, keep rolling until you are face down again. Otherwise, don't move and don't make any sound until you're sure the bear is gone.
If you are faced with a quiet bear that won't leave, you'll probably have to fight the bear or at least make it think you want to. If backing away doesn't keep the bear from you and it is behaving calmly, act aggressively to let the bear know that you are not an easy meal. Yell at the bear, make yourself appear as large as possible, throw things at it, swing a large stick at it, and make eye contact. The idea is to make the bear think that since you are crazy enough to fight a bear, it probably shouldn't be messing with you. If the bear decides to attack anyway, fight back with a focus on its face. If you have bear spray, use in situations where the bear is aggressively approaching you. Make sure you are not spraying into the wind, and don't spray it on yourself as a repellent. Read the instructions.
The reason I chose bear safety this week is because I just had my first bear encounter while camping in Virginia. I was tent camping about 30 miles south of Washington, DC and while I got up to use the bathroom at 1 AM a bear took advantage of my absence and ransacked my campsite. It put some holes in my tent, knocked my cooler off the picnic table, and tipped over my folding chair. What did I do wrong? I had my alarm set for 5:30 AM so I could catch an early train into the city. To move more quickly, I had my next day's clothes and my toiletries in the tent with me. That was my first mistake. My second mistake was leaving the cooler in the open. I had 8 bottles of water and 3 glass bottles of root beer in there. I decided the ice would last longer in the woods than it would in the car when drove into civilization, where it's generally hotter. My third mistake, which wasn't really a mistake but just the circumstances, was not having safety in numbers. Bears don't like people; we have a bad reputation in the animal world. Being off-season in the middle of the week, the campground was pretty much empty. With no people around, maybe the bear felt like the campground was OK to stroll through, and the only tent around was an easy target.

Holes in the tent were on the right side, so I'm guessing
the bear moved right to left, swatting the chair over for
dramatic effect.

When I came back to the campsite, the bear was gone. The tent was a heap, so I spent the rest of the night in the car with the doors locked. Yes, I've seen a news article where a bear gets in a car and steals it.  After sunrise, I inspected the damage. There were holes in the tent, nothing too big but they'll only grow each time the tent is set up. None of the drinks were opened and the glass bottles didn't break. Despite their superhuman strength, bears still need you to open a bottle for them. The chair was fine, but I have no idea why the bear decided to flip it. With a damaged tent, I ended my trip a day early. This week's bear safety tips come from the Grizzly and Wolf Discovery Center right outside fabulous Yellowstone National Park.

Cave Life

This week is Cave Week, so to celebrate we're going spelunking to see what critters we can find. In addition to all sorts of whimsical formations, caves host a surprising amount of life. There are trogolobites, which live full time in caves; trogolophiles, which live in a cave but can also survive outside; and trogoloxenes, the part time cave denizens. You can encounter insects, fish, birds, mammals, plants, fungi, and others. Because there is very little natural light, many of these species are adapted to live in darkness; some don't even have eyes.

Whimsical cave formations

The first cave critter that comes to mind is a bat. Many bats roost in caves because they are cool and dark during the day, making it easier to sleep. Caves make a great place to hibernate over the winter. A constant temperature that is above freezing is an obvious plus, but it's cool enough to trigger the hibernation process. Other cave mammals include bears and jumping mice.

To the bat cave! (National Science Foundation)

Plants are a rare find in  caves because they need sunlight for photosynthesis. I saw ferns growing in a cave under a ceiling hole that opened to the surface. Much more common are fungi, which thrive in dark, damp conditions. Most important among them is Pseudogymnoascus destructans, which causes White Nose Syndrome in bats. It is devastating bat colonies across the US and Canada, and enjoys the cool temperatures while the bats hibernate.

White Nose Syndrome affecting these bats (NPS)

Cave fish are interesting little critters. Nearly all lack eyes and skin pigment. With no light to see by, there is no need to camouflage or stand out, so they are likely to be white or light colored. Unable to see their food, they find it by sensing movement in the water. What exactly do they eat? Since plants, the base of the food chain can't really live in a cave, anything in there either needs to go outside for good or eat whatever gets brought in. Cave fish eat detritus that washes in during rain events. Other critters get by on dung, the leaving of larger animals that way out.

Blind cave fish (NPS, Rick Olsen)

Cave Week runs through this weekend. Find a cave near you and check it out. Spelunk safely. Use the buddy system, carry at least three light sources, and make sure someone knows where you are going. Don't disturb any wildlife and make sure clothing and equipment are thoroughly cleaned before entering another cave. This helps prevent the spread of White Nose Syndrome.
This week's information comes from the National Park Service and National Geographic.

Species of the Month

Spring has officially arrived, and with it, the birds and the bees. March's Species of the Month is a bee, the American bumblebee. This and other bees are just beginning to make appearances in my neck of the woods. Cute and fuzzy, they fly despite the laws of aerodynamics stating otherwise. Lucky for them, they don't use aerodynamics to fly.
  

Scientific name: Bombus Pensylvanicus

Kingdom: Animalia (animals)

Class: Insecta (insects)

Order: Hymenoptera (ants, bees, wasps, sawflies)

Range: Eastern North America from Quebec south to Florida, west to the Rockies

Habitat: open fields

Lifespan: Up to a year

Diet: pollen (favors sunflower, clover, vetch)

Predators: Birds, spiders, other bees, small mammals

Conservation Status: Threatened

Other Information: Bumblebees live in a family colony. A queen emerges from hibernation first and begins searching for a suitable nesting site to lay her eggs. She feeds the larva, which grow into workers that feed the next batch of larva to hatch. In summer, males and queens hatch, then leave the nest to mate. The queens go into hibernation for the winter while the males and workers die. American bumblebees are a later emerging species. They are able to regulate their body temperatures like mammals do. American bumblebees, like other bumbles and bees in general, are declining in number. Several factors are thought to contribute, including habitat loss and pesticides.
This week's information comes from Iowa State University's Bug Guide and the US Forest Service. The pictures are from the State of Montana's Montana Field Guide.

Migration

The days are getting shorter and cooler. Leaves are starting to turn and fall. Winter is approaching, and many animals are have already begun their seasonal migration. While some hibernate to avoid unfavorable seasonal habitat conditions, others move temporarily to more suitable habitat.

Migrations occur across all different animal classes: birds do it, and so do mammals, fish, insects, reptiles, amphibians, and crustaceans. Even some people do it. Florida and Arizona get plenty of snowbirds from up north every winter. More traditionally, nomadic tribes still exist in Africa and Asia living as they have for centuries.

We’re an ecology blog, not an anthropology blog so let’s forget about nomads for a minute. Perhaps the most visible migrations here in America are those of birds and monarch butterflies. Birds migrate to and from pretty much everywhere. Some stay within North America when migrating while others fly from pole to pole. Others, of course, are somewhere in between.

We’ll use the Baltimore oriole as an example of avian migration. They arrive in the eastern US from Central and northern South America in April and May. This is their breeding ground. They begin nesting right away and eggs usually hatch in June. Southern migration begins as early as July and has peaked by September.

Baltimore oriole (NPS)

Monarch butterflies journey to Mexico in a multi-generational migration. Northern monarchs go south to the oyamel fir trees in the mountains of central Mexico. Millions of them cover the trees. After winter, they head north again, laying eggs on milkweed plants. Caterpillars hatch in a few days and eat the plants before forming a chrysalis. A new butterfly emerges and continues the northward journey, stopping at milkweed to lay eggs and start the hatching and migrating process over again. The northernmost monarchs are able to return to Mexico in a single journey.

Monarch butterfly

The pronghorn in Wyoming migrates vertically. It moves from summer grounds in Grand Teton National Park about 150 miles south to lower elevation in the sagebrush habitats of the Green River area. This is North America’s longest mammal migration.

Pronghorn

Not all migration is seasonal. Zooplankton in the ocean migrate vertically through the water column on a daily basis. At night the move toward the surface, and by sunrise they are headed back to the briny deep. While a journey of hundreds or thousands of feet might not seem like much to you, keep in mind that these tiny critters probably can’t see as far as the other end of a yardstick.

Zooplankton (Nature International Journal of Science)

Fall migration is happening now. Who is moving through your neck of the woods?

This week's information comes from:

Journey North (Baltimore oriole)

National Geographic (monarch butterfly)

Wildlife Conservation Society (pronghorn)

Nature International Journal of Science (zooplankton)

Winter Adaptations

As I deal with a pair of winter storms over the course of writing this blog, I am sitting cozy and warm inside my house. How do animals, who don’t live in houses with central heating or furnaces make it through the winter? Some migrate to warmer areas, but those that stay behind have special adaptations that help them cope with the cold and snowy weather.

Many animals go into mega energy conservation mode during the winter because not only do they lack heating systems for their homes, they also lack supermarkets that carry a reliable food source. For herbivores, their plant-based food supply is either dormant (and not producing the nutritious shoots they crave), or buried under snow and ice. Whether warm-blooded or cold-blooded, both need to keep warm to survive. Cold-blooded critters rely on the sun’s radiant heat to stay warm, and this is a challenge when it’s cold outside and the sun isn’t reliable. Warm-blooded critters metabolize food to stay warm- they eat much more than cold-blooded ones. One option to keep up metabolism is to spend energy to search for scarce food. But there are other ways to get by.

Hibernation is probably the first coping mechanism you think of, and it’s quite common in the mammal world. Bears do it, bats do it. What is it, compared to normal sleep? When you go to sleep your body slows down. Breathing and heart rate go down and metabolism slows, and your body temperature cools a bit. Hibernation is an extreme version of this. But to be asleep for weeks or months on end requires quite a bit of sustaining energy, even if bodily functions slow to the point of nearly stopping. That’s why bears go on a feed frenzy each fall, gorging themselves on spawning salmon or high-energy moths if they live in the right place.

NPS graphic of a hibernating bear

For those that don’t hibernate, finding food is a priority. Arctic foxes and snowshoe hares both grow a white coat for snow camouflage. The fox uses its camo to hunt; the hare uses its to avoid being eaten. The bison uses its large head as a snowplow to uncover buried vegetation. Ever wonder what that large hump at its shoulder is? Extra muscles to support all that head.

Snowshoe hare (Montana Fish, Wildlife, and Parks)

Bison plowing for food (NPS)

Preserving body heat is a great way to maximize caloric efficiency. The thick fur coat of a muskox traps body heat. Blubber insulates whales, seals, and walruses. Polar bears have black skin that absorbs heat, and their fur traps heat, including body heat that they radiate.

Walruses (US Fish and Wildlife Service)

Ease of mobility is also an efficiency adaptation. Lynxes and caribou both have large feet that act as snowshoes, making it easier to get around so they burn fewer calories doing so.

Check out the foot on that lynx! (Natural Resources Research Institute)

These are just a few of the many adaptations that make survival possible for warm-blooded mammals. There are others, and there are also adaptations for cold-blooded animals (like a frog with antifreeze in its blood) and plants too! Enjoy your heater for the rest of the winter! 

Bats and White Nose Syndrome

Bats are a misunderstood and unreasonably feared critter. Some species rid our skies of pest insects, while others pollinate crops and other plants. Bat poop (guano) is a rich fertilizer. Attitudes are changing as people begin to appreciate the ecosystem services bats provide but now they face another threat, White Nose Syndrome.

White Nose Syndrome (WNS) is a fungal infection that is destroying bat colonies at an unprecedented rate. The fungus Pseudogymnoscus destructans was likely introduced from Europe inadvertently. It thrives in the cold strikes bats when they are hibernating. Bats hibernate to conserve energy when their food source (insects or fruit) is unavailable, but the infection causes them to wake from hibernation. Being awake increases metabolism and other bodily functions, and the bats starve to death because of burning through whatever energy they had stored to make it through the winter. To answer your next question, “How does being awake kill a bat?”, most of the calories you need in a day are just to keep you alive- breathing, circulation, and the biggest energy consumer- temperature regulation.

WNS spreads from direct contact with an infected bat or from surface contamination inside a bat cave. People can transport the fungus from cave to cave, so spelunkers must decontaminate clothing, shoes, and equipment in between caves. 

Bats infected with WNS (National Park Service photo)

WNS has killed millions of bats in the eastern parts of the US and Canada is spreading west. Last year the first case was discovered here in Washington. Washington Department of Fish and Wildlife conducted a bat count a few weeks ago at Northwest Trek as the beginning of an effort to monitor bat colonies and WNS. A follow-up count took place this past weekend and I took part.

The goal is to count the number of bats seen leaving and entering the nest. Exits minus entries is the total number of bats seen. The tricky part is seeing them as it gets darker. I did OK with this until about 9:20. The freaky part is not seeing the bats until they are inches from your face, then they turn away at the last second, mostly to my left. I could their wings flapping as they passed by my head.

By establishing a baseline this year the state hopes to track population trends that could indicate colonies in trouble. This can be tricky, though. Bats sometimes tend to not roost in the same location night after night. For example, the site I counted was unmonitored in the previous count. The only reason I was posted there was because on the way into Northwest Trek we heard the bats making sounds inside the park entryway. My total for the night was around 60 bats. Other sites inside the park had a lower count than during the previous survey. It is possible that my site had an increase since the last survey, but that is unknown since no one counted there the first time. 

Me counting bats

In just six years since its introduction, WNS had killed millions of bats with a mortality rate up to 100% in some colonies, according to the US Fish and Wildlife Service. Fighting back will be a long process, but the key first step is monitoring. I am glad I had a chance to take part in the beginning of what I hope will be a successful fight. WNS info this week comes from the National Park Service, one of many partners in the search for a cure.

NPS: https://www.nps.gov/articles/what-is-white-nose-syndrome.htm

USFWS: http://www.batcon.org/pdfs/USFWS_WNS_Mortality_2012_NR_FINAL.pdf

Still Hungry, Bearly Full

Time for a look at one of America’s most charismatic critters, the bear. We have three bear species (not Papa, Mama, and Baby). They are the black bear, which is the most wide-ranging, the grizzly, and the polar bear.

Grizzly bear (UNAGB)

Polar bear (Scientific American)

Black bear (ABC News)

Bears are omnivores, meaning the eat plant and animal products. Always the opportunists, they won’t hesitate to raid a dumpster or campsite. One of the reasons wildlife managers discourage you from feeding the bears is because they will learn to equate people with food. Once bears start looking for people, problems arise.

Processed bear food

Bears are very large, so it takes quite a bit of food to keep them going. Grizzlies and black bears sleep through most of the winter (called torpor- not all of them hibernate all the way through) and that helps them by not eating when food sources are most scarce. The rest of the year, they are eating to make up for their long winter’s nap. Sometimes bears will strip the bark from a tree and power up with sugary sap when they first emerge from torpor.

Tree sap breakfast nook

From then on, they are pretty much fattening up for the winter. In the Northwest (including Alaska and Pacific Canada), bears get a big boost of tasty fat in the form of salmon, which return to spawn just before bear bedtime. In the Rockies, an infusion of migratory moths makes an easy treat for the bears that know where to look. The salmon and moths giving the bears a goodnight kiss is another example of nature’s perfect timing.

Photo credits: 

Grizzly: United Nations Association of Great Boston https://unagb.wordpress.com/tag/grizzly-bears/

Polar bear: Scientific American https://www.scientificamerican.com/article/polar-bears-diverged-from-brown-bears-fairly-recently/

Black Bear: ABC News http://abcnews.go.com/US/florida-black-bear-takes-break-rests-hammock/story?id=23940797

Species of the Month: Groundhog

February’s Species of the Month is another little critter we associate with winter weather. Or spring. It’s everyone’s favorite amateur weather prognosticator, the groundhog. No matter what his prediction is, it is still six weeks until spring and six weeks of winter. Information and picture this month come from University of Michigan’s Animal Diversity Web.

Scientific name: Marmota monax

Kingdom: Animalia (animals)

Class: Mammalia (mammals)

Order: Rodentia (rodents)

Range: Eastern US from the South to eastern Canada, west across Canada as far north as southern Alaska

Habitat: Grassland, forest, urban and agricultural areas.

Lifespan: 4-6 years

Diet: leaves, bark, seeds, grain, flowers, insects, eggs, mollusks

Predators: wolves, coyotes, foxes, bears, lynx, bobcats, hawks, snakes, domestic dogs

Conservation Status: No special protection

Other Information: Also known as the woodchuck and whistle pig. If it could chuck wood, it chucks unknown amounts. Abandoned dens find new life hosting a diverse array of critters including foxes, ground squirrels, skunks, and raccoons. Ecosystem functions groundhogs perform are seed distribution and soil aeration. They are able to climb trees and make a whistling call when frightened. Other sounds are hissing, growling, and teeth chattering. A hibernator, they sometimes wake up early, giving rise to the Groundhog Day legend. Favorite plant foods include clover and dandelion. Groundhogs are used for biomedical research and are a crop pest.

Solar-powered Cycles

You probably noticed by now that the days are getting shorter and the air is a little chillier. Fall has fallen! The sun gives life to everything on Earth through heat and energy for plant photosynthesis. It also triggers changes in life cycles, some of which are evident to almost everyone right now.

The most obvious cycle that is affected by the sun is the current situation with our tree leaves changing colors and falling off. Because Earth’s axis is tilted 23 degrees, we experience seasonal variances in the amount of sunlight we get. As we move through fall and into winter, the sun sinks lower in the sky and light that hits us is less direct.

Nature loves efficiency, and trees lose their leaves this time of year because with decreasing sunlight, they would expend more energy performing photosynthesis (turning sunlight, water, and carbon dioxide into energy) than they would get from it. Chlorophyll, the active photosynthesizing pigment, dries up and the cells in the leaf stem die, weakening it to the point that it falls off the tree. Until spring arrives, trees and other plants live off of starches stored in their roots. That starch is the byproduct of photosynthesis.

Other seasonal cycles are the leafing out of trees, hibernation, and mating seasons. Some cycles run by the sun can be daily, not just seasonal. Dandelions and other flowers close their petals at night. Daily sleep cycles are also affected by sunlight. Animals don’t use an alarm clock, but they do have an internal clock.

Bigleaf maple

Even shrubs change colors