Sunday, January 26, 2014

Winterberry Holly





            Many people are unaware that most of our native hollies are actually deciduous, losing their leaves in the winter, because they are only aware of the evergreen American Holly. The most well-known of these other hollies is Winterberry, Ilex verticillata. Like most hollies, they are dioecious (male and female flowers on separate plants), so only female trees produce fruit and only if there is a male tree nearby to provide pollination. This northernmost of all our hollies holds onto its berries well into winter, thus its most common name. The berries are not a favored food of any animal I am familiar with, which explains why the berries last so long. Rather, they serve as starvation food and may actually be more palatable to birds as the cold changes the chemical properties of the fruit. This makes them a popular garden planting since the long-lasting, bright berries add color to the often bleak and cold landscape. They are easy to grow as well and are a small enough shrub (most only reach 15’ or so) to fit into many plantings. It seems that hybrids and cultivated varieties (cultivars) are even less desirable as animal food and the berries may not even be touched on these plantings except in desperation.

If visited by a pollinator carrying male pollen, these female flowers will become berries.
Humans have used this shrub though for more than its decorative features in the past. It was used medicinally, despite its potentially toxic berries, for example. One of its other names hints at its medical use: Feverbush. In fact, it has been listed in some medical journals, including what is now often referred to as the “Confederate Ethnobotany.” This was Confederate doctor Francis Porcher's work finding alternative medicines for goods no longer available due to Union war time blockades. It was listed there as not only treating fevers, but for diarrhea, ulcers, as a medical wash, and even to treat gangrene. Despite its toxic berries and possibly bark, the dried leaves were sometimes used for tea as well (like its evergreen American Holly cousin). Many Native American Indian tribes also made medicinal use of it, such as the Haudenosanee (Iroquois) who used such parts as its bark and berries to induce vomiting and as a laxative.
I have often been entertained by watching a Mockingbird try to defend its winterberry patch from other birds like Robins, who mob it after the cold weather is over and the fruits are one of the few foods left. Much better to simply enjoy Winterberry's beauty and let the birds experiment with eating it I think. Here's a short video of a Mockingbird in its Winterberry bush:
                                 https://www.youtube.com/watch?v=PEV80CevsJk

A Robin eats a fruit late in the winter.

Tuesday, January 21, 2014

Carolina Chickadee, The Bringer of News


A Carolina Chickadee at the Long Branch Nature Center feeder 

       The cold snap today reminded me of one of our best loved backyard birds, the Carolina Chickadee (Poecile carolinensis). Their energy and resourcefulness, along with some unique biological adaptations, allow them to live in our yards year round despite the weather. In winter, when most other insect eating-birds have migrated, they augment their diet with seeds. People who feed birds are likely to find chickadees to be among their best customers, being particularly fond of black oil sunflower seeds. Feeders can be a real benefit when it gets extremely cold (under 10 degrees F). Chickadees need 20 times more food in winter than summer to maintain their metabolisms, so the extra seed or suet can be a life saver. Finding 60% (the equivalent of 250 sunflower seeds for a chickadee) of their body weight in food each day is not easy. As if planning ahead, they frequently cache food away under loose bark or other nooks and crannies.
     Chickadees have several ways of conserving energy in winter. Like most birds, they fluff up their feathers (of which they grow up to 30% more in winter) to trap body-warmed air. They also can reduce their body temperature as much as 20 degrees on winter nights to conserve fat reserves, an adaptive form of hypothermia.
     Chickadees are extremely curious and often take unwarranted risks. Bird watchers know that it’s often a chickadee that’s first to respond to the “pishing” call “birders” use to lure birds out into the open. They often lead mixed flocks of birds in mobbing screech owls and other predators as well. Some of their many calls are used to warn each other and even other animals of danger also. Tom Starr, a notable figure in Cherokee history, claimed to have had his life saved when he heard a tsikilili (chickadee) give its warning call. He realized he was being followed and supposedly escaped to safety. To the Cherokee, a tsikilili is considered a bringer of news. I believe Tom Starr’s story. Oftentimes I’ve heard chickadees raising a ruckus and investigated. Usually it was just a cat, but sometimes it was a snake, screech owl, or something even more interesting.
     Once I was testing my skills calling turkeys at a park where I worked, when the gobblers I was “talking” to suddenly went quiet. I thought I had hit a sour note when I heard something approaching me. It was a red fox, apparently looking for a turkey dinner. Several chickadees heralded his arrival, and it may have been their calls that saved a turkey’s life. The chickadees got to within a foot or so of that fox (and the fox got within 5 feet of me before I stood up and gave it a good scare), trusting in their quickness to let them get away. With that much commotion and pestering, it would have been hard to sneak up on anything.
     It’s easy to get chickadees to nest in your yard, as they will use just about any bird box, but you can exclude larger birds by making the entrance hole about 1-1/8”. Try putting a box up in February (they may even roost in it on colder winter nights) in an evergreen tree if possible. Six to 12 feet is plenty high. You can increase the chances of getting them to accept your gift by placing some leaves inside, since chickadees often use “house cleaning” as a pair bonding ritual. If you get them to nest, don’t disturb them. You might get a surprise if you do, as female chickadees can produce a scary snake-like hiss. More importantly, you can cause harm by stressing them and it’s illegal to bother nesting wildlife anyways.
     Some people have tamed chickadees to the point of eating out of their hands. I once did. It was amusing to watch them chisel open seeds or try and wrestle them from my fingers when I refused to let go. They seem to pick the fattest seeds first, normally taking them to a more secluded place to actually eat them. Even if you don’t have as bold chickadees as I had, these little dynamos are fun to watch all year long, whether pestering a predator, stealing a tuft of hair from a dog for their nest, or making use of a bird house. Since chickadees can live up to 12 years (though wild ones live much shorter lives) and are so easy to attract, you may want to be a good neighbor and really get to know them.

Saturday, January 18, 2014

Fall Cankerworms





Male and female Fall Cankwerworms
 
    It may not look like it, but both insects pictured are the same species. They are Fall Cankerworms, Alsophila pometaria, and in this species, the females are wingless. This is one of the very few moths who remain active through winter, at least during warmer days. These Geometrid (inchworm) moths mature this late in the year and thus avoid many potential predators.
    The females of course cannot fly, sacrificing wings in order to be able to commit more resources to egg production. They send out pheromones to attract the winged males and then lay their eggs in cracks and crevices in trees. The emerging caterpillars "balloon" in the spring by sending silk out to be carried by the wind to the various trees and shrubs they feed on.
    There are many other unusual characteristics to this moth: how females produce genetic copies of themselves some seasons, how the variable caterpillars are usually light green when in low numbers but almost black when there are many, and other traits, but we will return to talk about these during the summer when we find their larvae.    
    For now, if you find a moth out and about this time of year, there's a good chance it's a Fall Cankerworm. I actually tried to move the female over and see if I could act as match-maker, but the female apparently was not sending out any pheromones.
 

Wednesday, January 15, 2014

Winter Berries

Red Chokeberries from my yard.

American Holly with berries.

    As you may know, the purpose of a ripe berry or fruit is for it to be eaten by the right frugivore (fruit eater) for its seeds to hopefully be dispersed to the proper site for germination (and with built in fertilizer). That is why berries and many fruits change color, to advertise when they are ripe and at their best to be eaten. In fact, many seeds actually germinate better after traveling through the digestive system of an animal. 
    But not all berries are preferred the same. For example, many winter fruits and berries are not well liked and stay on the plants for extended periods of time, serving instead as starvation food. That is why such plants as chokeberries, sumacs, coralberries, and hollies hold onto their fruits well into the winter season, providing color to dreary landscapes and gardeners. They certainly are not favorite foods, but have adapted themselves to being necessary and not having much competition when seeking to be eaten and spread during this season.
    Many of these fruits and berries are thought to be affected by the cold weather, perhaps tasting better as the cold breaks down or changes their chemical properties. By the time birds are desperate enough to eat them, they may taste better anyways. Regardless, to flocks of robins and such in March, these berries may well be life savers. This year however, I've noticed that many of these have already been consumed when they would normally still be hanging on the bushes and trees. This may be due to shortages of other foods or severe cold weather, or may be its just something very local. But what worries me is that we still have a ways to go and more potential bad weather coming. Hopefully the birds and other animals will find other foods or move elsewhere if need be.