Sunday, June 27, 2010

Birds in June

(Robin's nest in a Syringa.  Why are the eggs of the American robin blue?)

I spent an hour this morning appraising the avian situation in my forest.  Male singing has changed over the past month in an interesting way.  Species that were quite vocal earlier in May are now fairly quiet, but others are singing constantly.  Dark-eyed juncos, chipping sparrows, song sparrows, black-capped chickadees, wood thrushes, all the woodpeckers, white-breasted nuthatches, eastern phoebes, American robins, gray catbirds, and blue-headed vireos are relatively inconspicuous now.  I assume that the frequency of bird song is correlated to the stage of the nesting cycle.  Males sing to keep other males at arm’s length and to attract females.  When the male or female (usually the female) is incubating eggs or tending nestlings, males tend to be quieter.  I am sure this is to avoid attracting predators to their territory, where the nest is located.

But other species are quite vocal.  Ovenbirds, red-eyed vireos, great-crested flycatchers, eastern wood pewees, and veerys are still waking me up early in the morning.  Because they returned from migration later than the group of silent species, some of whom are year-round residents, these late arrivals may be further behind in their nesting chronology.  If they are mated, then they must be at an earlier stage of the nesting cycle.

Some of this can be documented.  The phoebe nest hatched five nestlings about three weeks ago, and they are now working on their second brood of the season.  By the way, I covered this bird in a blog several weeks ago.  It turns out that this pair nested on a window ledge on the back of my house rather than on the light fixture on the front.  The chickadees that I described last week are now incubating eggs.  And I found a nest yesterday of an American robin in a Syringa shrub next to the house with four eggs.

But let’s review songbird nesting chronology a bit.  Males establish territories, sing, and, if fortunate, acquire a mate.  One or both adults build a nest, which is distinctive to that species (i.e., mud, moss, grass stems, twigs).  Bird nests are truly marvels of the animal world.  How birds actually build these structures amazes me constantly.  During this stage, they copulate, which is done by the male hovering in flight above the female; their cloacas touch, sperm is transferred, and voila. When the nest is complete, the female will start laying eggs.  Egg-laying occurs early in the morning, and the female lays only one egg per day.  Even the famous while leghorn chicken, which has been bred to do nothing but produce and lay eggs, can only lay one egg per day.

Clutch size varies from about 3-6 in temperate species, but the number is relatively fixed within a species.  One of the parents, usually the female, then begins incubating the clutch after the next-to-last, or penultimate, egg is laid.  Eggs do not begin developing until the heat from the female’s body is applied during incubation.  The last egg laid, which occurs one day after incubation starts, will hatch about 24 hours after the rest of the clutch; this “runt” of the litter is often the one not to survive because it is always one day smaller than its siblings.  Incubation takes about 10-14 days, depending on species, and then the real work begins.

One or both parents must then find food, and I mean a lot of food, to feed the hungry nestlings.  These morsels usually consist of insects or other invertebrates, which are high in protein.  Nestlings fledge from the nest after 10-12 days.  For large birds like hawks, incubation and the nestling period are about three times as long as for small songbirds.  If you have never found a nest of a small bird and followed it, you should do so.  The rate at which nestlings grow is truly astounding.  You can see the difference in size and feather development every 24 hours.  But here is a puzzle.  Those nestlings have to defecate several times per day, and yet you will see no feces in the nest.  Where is it?

Will you cause the adults to abandon the nest if you find it and check on it up close once or twice a day?  It depends.  If the adults are only at the nest-building stage, they may abandon that effort and relocate because they “think” a predator has found the nest.  Why continue if something is going to eat your eggs?  But once they have reached incubation stage, they will usually not abandon the nest.  Too much time and energy have now gone into that nest to just walk away.  So find an active nest, observe it until the babies fledge, and report to us here.  There are worse family activities in which you could be involved.

Once the young have fledged, many males will begin singing all over again in the hopes of attracting a new female who wants to nest.  And on it goes, throughout the ages—the stuff of which poems are made.

Friday, June 18, 2010

On the importance of homemade strawberry jam

(Scotch and homemade strawberry jam.  A nearly complete diet for DrTom, leading to order and homeostasis.)

There are certain stabilizers in our lives that become absolutely essential to our feeling of order and homeostasis.  For some, it is finding the morning paper on the front porch by 7am every day.  For others, it is that hot cup of organically grown Cafe Britt coffee about mid-morning.  And for still others, it is watching the Yankees play on tv during the summer.  One of mine is having a single-malt scotch and a cigar in the evening, something I have discussed many times.  It is during that hour or so that I contemplate the day's activities and life's memories--of children and grandchildren, of gardens and plantings growing around my property, of former students who left an impression.  I am counting on having those memories until senescence and lack of eyesight completely take over and all I can do is pet the dog or the woodchuck, or whatever that furry thing is that is lying at my feet.

But there is one other stable element in my life-homemade strawberry jam. Most years, my wife and I visit a local farm where you pick your own strawberries.  We bring them home, clean them up a bit, and my wife makes jam.  That's right.  Women make the jam, men mow the lawn.  This division of labor has worked pretty well for centuries, so far be it from me to change it.  But this year, my wife couldn't pick berries because she had some eye surgery the day before and was instructed not to bend over.  So, I went to the berry patch alone, wearing my white head band to keep the sweat from rolling into my eyes and sporting an Aussie hat.  Bending over those raised beds of berries is tough on a "mature" body like mine, so I found that actually lying down in the narrow row next to the bed worked best, and then inching forward as I depleted the ripe fruit that was close at hand.  No one else in the field was using this technique, possibly because it looked like I was a Navy Seal crawling up the beach to surprise the enemy in Mogadishu.  I didn't care.  It was more comfortable than bending over, and this color-blind naturalist needs to be close to his work to find red berries easily.  I picked 20 pounds and went home.

When I got home, it became clear that my wife was busy preparing for guests who were arriving the next day, and the chore of making jam would pretty much fall on the now ex-Navy Seal.  Amazing how some men can lay aside their M-16 and grenade launcher after a successful mission in the berry patch to don an apron and to manipulate a canning jar in the kitchen.  But on this day, that is what I did.  

As my wife barked instructions, I snapped to attention.  Clean fruit, cut it up, and mash until you have 5 cups.  Put in pan on stove, add a pat of butter, and one box of Sure-Jell.  Bring to a boil.  Then, add 7 cups of sugar.  Bring to a rolling boil for 1 minute.  Remove from heat.  Skim off solids on top of liquid.  In the meantime, I had a very large pot on the stove containing boiling water and the jars, lids, and rings.  Steam everywhere.  Lots of heat in that part of the kitchen.  This is why old farmhouses used to have a summer kitchen to do this kind of work.  Remove the jars, fill with cooked jam, wipe off the rim of jar with a hot, wet paper towel, place lid on top, and screw on a ring.  Then place all the filled jars back into the water bath to boil for a few minutes.  Two fingers and 1 thumb now burned.  Remove from heat, set on table, and enjoy the sound of those lids snapping down into place as the vacuum inside the jar takes hold.  As one batch is finished, begin the assembly line for the next load of fruit.  Two more fingers burned.  Keep going.  Don't stop or slow down, or you will find something else to do.  It is hot, sweaty work, but someone has to do it.  It is essential work, because we are talkin homemade strawberry jam--nectar of the Gods, sweet memories, winter morning comfort.

I made 20 pints of jam, so this should last until next June.  But my wife has a tendency to give our jam away as gifts.  And our grandchildren are always asking for "Grandma's jam".  But not this year.  Because I labored over the brew, I now hold the keys to this year's supply.  I love my grandkids, but all that sugar is probably not good for them.  And little kids need to learn that life is not always fair.  And maybe they are allergic to red things.  That you don't always get what you want, when you want it.  And that "Grandma's jam" is sometimes "Grandpa's jam".  And Grandpas can be stingy.

So, toast with strawberry jam in the morning, and a single-malt scotch and a cigar in the evening.  Throw in a couple of vitamin pills, and I suppose this is a nearly complete diet leading to order and homeostasis.