Category: Learn

31 Dec 2018

Puff Ball-Eating Machines

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What comes to mind when you see a bright red cardinal in the winter? Beauty. Male. Contrast. Christmas. Charley Harper. What about awe? If you find yourself grumbling about how you don’t want to go outside and fill up the feeder again (because it’s too cold, you just filled it, or because they are costing you a pretty penny), think about how birds are exposed to nonstop cold temperatures this time of year. While our water fowl migrate during winter, most of our local birds (white-breasted nuthatch, finches, Carolina chickadee, northern cardinal, woodpeckers, wrens, tufted titmouse, blue jay, mourning dove, and more) tough it out all winter long. Clearly if they are so well adapted to survive cold winters, they could forage their own seeds and insects, but it’s a win-win to give them a little energy boost while getting to enjoy some local wildlife. In fact, most passerines (perching birds) are eating as much as they can during the day just to make it through the night. An excuse you don’t have this holiday season. On really cold nights, tiny chickadees and other passerines undergo ‘nightly hypothermia,’ meaning they use up all of their energy to keep warm by shivering. Birds would probably shiver themselves right off the branch if it weren’t for their special gripping feet. I know what you’re thinking, those dainty feet look as if they might break just by landing! The tendons in their feet have an involuntary reflex that automatically locks their toes around the perch when they land and unlocks when they straighten their legs. Now you know why birds make it look so easy to perch up on the tiniest branch at the tip top of a tree.
You don’t have to have fur like a deer or coyote to rock a winter coat. Passerines have quite the stylish and practical winter coats, made with a new set of down feathers. Fluffing up these feathers creates warm air pockets and keeps cold air away from their skin. Sorry to break it to you that birds aren’t looking like cute little puff balls for your enjoyment (although I do tend to want to give birds more food when they look like that). A common misconception about birds is their nesting area. Nests are used during breeding season in the spring and summer. This time of year, most birds don’t have a designated home, so they roost in a new spot every night. Some birds use old woodpecker holes and cavities in trees or seek out evergreens, thickets, and shrubby areas for protection from both predators and low temperatures. I encourage you to not only give our feathered friends mad props while they are crunching their way through your seed, but to go on a hike to look for small tree cavities and other good overnight roosting spots.

~Tracy

29 Oct 2018

Horsehair Worms

There’s something about long, thin worms that puts people on edge. Even I hesitated to pick up this little guy because of the fear of parasitic worms. Don’t worry, these horsehair worms (Gordius robustus) are not some parasitic nematode ready to crawl up your nose and take over your body. Well actually, I should clarify. You’re safe if you are a human. Even your pets are safe. However, if you’re an arthropod, you might be in trouble. The mature adults (like you see in the picture) aren’t the ones causing problems. It’s the babies you have to look out for, and you won’t even see them coming!

Adult females lay MILLIONS of eggs in the water. The minuscule (~0.01 inches) larvae are ingested by certain bugs for food. A hard covering (cyst) protects the larva, then dissolves after entering the gut of its host. Many macroinvertebrates become hosts because they live in aquatic habitats. Other common hosts are crickets, grasshoppers, and beetles because they eat macroinvertebrates, thus becoming the new host to the horsehair worm. As a horsehair worm develops into an adult over a few weeks or months, the host becomes the ‘walking dead’. Because adult horsehair worms require water to leave their host, the zombie host bug is triggered to find water, where it meets its demise. Most of us have seen witches melting from water in the Wizard of Oz, but here’s a new visual for you: death by worm breaking through a body cavity. And if you really want a good visual, search for horsehair worms on youtube. You’ll find all sorts of videos of them crawling out of crickets, spiders, cockroaches, and other arthropods. Maybe save it for Halloween.

One legend behind their name is that people believed the hairs from a horse’s mane or tail would fall into the water bucket and come to life. In reality, a cricket or host had hopped up to the water bucket, prompting a horsehair worm to break free in the water source. They are also referred to as Gordian worms because they twist and squirm into ‘Gordian knots’. In addition to having a very remarkable life cycle, horsehair worms are important for keeping our pest population in check. I encourage you to go on a hike and keep an eye out for any strange behavior from arthropods around water.

~Tracy

18 Jun 2018

Parasitic Plants

The darkness of the forest seems quite alluring on these hot and humid days. The fresh growth of large green leaves brings welcomed relief from the beating sun. It’s here in the shaded area that you can find American Squawroot (Conopholis americana). Most plants along the forest floor are competing for limited sunlight in the slow motion battle of ‘who can grow faster towards the gap in the canopy’. However, rather than undergoing photosynthesis, this parasitic plant uses specialized roots (haustoria) to feed itself from the roots of oak trees. I know most of us hear “parasite” and think of leeches and ticks. Did you know that plants can suck the nutrients from other plants? Rather than using energy on chlorophyll, it surreptitiously absorbs nutrients underground for four years until it finally pushes its stems above ground. The odd looking scaled stems pop up in clusters above the plundered oak root. Because of its unique look, squawroot is often mistaken as a fungus in any of its above ground stages. Squawroot produces flowers in the spring, creating what looks like a cream-colored pine cone village for the local fairies (pic 1). Pollinators such as flies and bees feed from the flowers, forming a seed capsule with multiple seeds in each scale (pic 2). The plants become more and more brown with time, and if you find them in the winter, you would think the poor fairies’ village had been burnt to a crisp. Some squawroot will reseed themselves, while other seeds are dispersed to new locations by foraging deer and other mammals. Another parasitic plant found in the area is beechdrop (Epifagus virginiana). Like squawroot, it is in the Orobanchaceae family, but it parasitizes beech trees rather than oaks (pic here). Squawroot may steal energy from the oak trees it parasitizes, but is not considered to be detrimental. It could only cause serious harm if the oak had a preexisting disease or illness.  I encourage you to enjoy a hike in the forest shade and try to find these unique plants!

~Tracy

04 Apr 2018

A Worm Lizard

More times than not, when I lift a log with a group of kids, I hear, “A worm!” The next guess is usually, “No, it’s a lizard!” In their defense, salamanders are slimy, with four disproportionately small legs attached to a long, slender body. They even cohabitate in leaf litter or under rocks and logs, though the worms better be careful because they (and many other invertebrates) are part of a salamander’s diet. They’re actually amphibians, and unlike lizards and reptiles, salamanders lack claws, external ear holes, and scales. Eastern red-backed salamanders (Plethodon cinereus) are one of the most common salamander species found in Eastern North America. They can be found in two morphs: red-back (pic 1) has a bright reddish stripe down its back; while lead-back (pic 2) lack the stripe and are mostly grayish-black. All color variations have the mottled black and white belly.

Red-backs belong to the family Plethodontidae, also known as the lungless salamanders. Thus, like their amphibian relatives, they breathe through their skin. These sals possess a nasolabial groove, a slit between their nostril and upper lip. It helps with chemical cues involved with courtship, territory, and food. These unique woodland salamanders lack the common aquatic larval stage and lay their eggs in small clusters in cavities under rocks and logs in early summer. It’s a shame they skip this stage because gilled salamander larvae are adorable, but I suppose it’s a pretty nifty adaptation that has evolved in this group. The larvae develop in the egg (gills and all) and hatch in late summer.

Have you ever seen a reddish-brown, slimy creature wriggling frantically? No head, no eyes, no legs…not segmented like a worm…furiously flipping back and forth? A salamander can drop its tail in a last attempt to save itself from being eaten. The tail distracts predators while the rest of the salamander dives out of sight into the safety of shelter. When I encountered this ‘flee of survival’, a child was the curious “predator” trying to pick it up. We must be careful while handling our skin-breathing amphibian friends and also remember that humans often have harmful substances on our hands such as sunscreen, soap residue, or lotion. The red-backs are in full force right now because the warm spring weather is allowing them to emerge from their winter underground hideouts. I encourage you to take a hike and carefully lift a log or large piece of bark to find some of these little sals. Just remember to put the roof back on their home!

~Tracy