An online resource based on the award-winning nature guide

Archive for March, 2020

American Crow Diet & Hunting Techniques

One would be hard pressed to name all of the different types of food that American Crows consume. The diet of these omnivorous birds runs the gamut —  small birds, bird eggs and nestlings, tadpoles, frogs and toads, snakes, turtles, small mammals, fish, insects, clams, nuts, fruits and carrion.

Crows use a number of techniques in obtaining their food. They find most of it as they’re walking on the ground, occasionally they probe just under its surface.  You often see them lifting and flipping leaves, cow pies, sticks and small stones to see what creatures live beneath them.  Crows have also been known to stand belly-deep in water as they hunt for fish. In addition, they sometimes hunt from a perch, pouncing on prey they see, and catch flying insects and small birds on the wing. Crows have even been observed using “tools” such as pieces of wood to probe for insects.

If their prey is large, crows will place it under one or both feet and tear pieces off with their bill (see pictured American Crow with road-killed Eastern Chipmunk it retrieved).

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


Wild Bird Seed

Humans have a long history of feeding birds. As early as 1500 BC Hindus provided birds (as well as dogs, insects, “wandering outcasts” and “beings of invisible worlds”) with rice cakes.  In 1825 one of the first bird feeders was constructed out of a modified cattle trough.  Bird feeding grew in popularity in the 1900’s and by 2019 roughly 60 million people in the U.S. were feeding birds, spending more than $4 billion annually on bird food. Bird feeding has become such a common practice that many people may wonder how seed-eating birds survived long, cold winters before humans fed them.

In fact, birds do very well without a helping hand from humans. A large number of winter bird species in the Northeast, especially sparrows and finches, are seedeaters (granivorous) and there are multiple wild sources of food for these birds, many found along roadsides and in fields.  These plants, called weeds by some, are known for the copious amounts of seeds they produce.  Ragweed, Pigweed, Bindweed, Thistle and Smartweed are some of the plants that are popular with seed-eating birds.  Some of the more familiar flowering plants such as Sulphur (or Rough-fruited) Cinquefoil, Mullein, St. John’s Wort, Black-eyed Susan, Evening Primrose, Queen Anne’s Lace, Yarrow and Goldenrod also feed a host of birds with their bounteous seed crops.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.


A Feathered Visitor

For the past six winters a Barred Owl has been a daily visitor at my house.  For most of these years, he roosted (and slept) all day every day from December through February on a White Birch tree just outside my door.  Although I usually try not to interfere with the natural rhythm of things, one year when the snow was exceptionally deep, making hunting quite challenging, I decided to offer the owl a daily treat – one small rodent.  Enough to entice him but not to satiate him or make him dependent upon this source of food. (I once opened up the gizzard of a road-killed Barred Owl and discovered five small rodents – they average about this amount per day.) Thanks to the Listserv in my town, I could appeal to residents for small rodents (trapped, not poisoned) which they generously deposited in a specially marked box outside the Town Hall, freshly frozen.

 

Every afternoon like clockwork the Barred Owl would become alert and open his eyes.  If he had left his perch during the day, he would return at dusk, precisely at 4:30 p.m. His timing appeared to be in sync with the amount of daylight, as he arrived a bit later as the days lengthened.  Most mornings I would take a mouse from the freezer and let it thaw (when I forgot, the microwave came in handy!).  I would take the mouse outside, dangle it by its tail to alert the observing owl, and place it on the railing of my porch. Practically before my hand released the mouse the owl would fly in, grasp the mouse on the fly in its talons and disappear into the woods. More than once I felt the tips of his wings brush against me.

Six years, 60 days a year, comes to 360 days…this owl has spent nearly a year, one-tenth of its life, outside my door.  I came upon the remains of a Barred Owl not even a quarter of a mile from my house this week.  I can only hope it wasn’t my friend.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com  and click on the yellow “donate” button.


Image

The Peace of Wild Things


Black Bears Active

Bears are emerging from hibernation a bit earlier than usual this year in Russia, Finland and the U.S. due to warmer temperatures.  The emergence of Black Bears from hibernation in the Northeast usually takes place next month, but they have already been active for several weeks, even in northern New England.

There is little food available to bears in April, but in March the situation is even more dire.  Therefore, bird feeders and human garbage are like bear magnets, so bring in your feeders and make your garbage inaccessible! The climate crisis is having a detrimental effect on wildlife — hibernation, migration and breeding cycles are intimately connected to the availability of food — and as a result of this out-of-sync timing, there will inevitably be more conflict between bears and humans.  (Photo: Black Bear scat filled with sunflower seeds from a bird feeder.  Thanks to Clyde Jenne and Bruce Locke for photo op.)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com  and click on the yellow “donate” button.


Time To Start Looking For & Recording Signs Of Spring

Moles are digging, Woolly Bears are emerging and preparing to pupate and develop into Isabella Tiger Moths, and Painted Turtles are emerging and warming their cool bodies by basking in the sun. Red-winged Blackbirds, Killdeer and Wood Ducks are back.  Silver Maple buds are beginning to swell.  Ticks are out and about.  New signs of spring are appearing on a daily basis, and those of us who keep nature journals are busy recording our discoveries.  These events may happen every year, but they never get old.

Studies based on the records that Henry David Thoreau and other naturalists kept for Concord, MA in the middle of the 19th century have found that the flowering of plants, leaf-out, butterfly emergence and the arrivals of some migratory birds are occurring earlier now than they did 165 years ago — anywhere from a day to three weeks earlier depending on the species — driven mostly by warmer spring temperatures.  Since the mid-1800’s Concord has lost roughly a quarter of its wildflowers while an additional third have become rare.

Whether it be through a written journal, sketches, photographs, videos or taped voice recordings, the observations we make today are a valuable resource for phenology (the timing of biological events) and climate change studies and for our own personal histories of natural places we visit year after year.  We are so fortunate that the current state of the world doesn’t prevent our appreciation of and participation in this annual spring ritual.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com  and click on the yellow “donate” button.


Female Winter Ticks Dropping Off Moose & Laying Eggs

One of the many injurious effects of climate change is the increase in Winter Ticks (Dermacentor albipictus) due to warmer New England winters.  These parasites spend their entire lives living off of one host and they have had a major impact on the moose population, especially on calves. Research conducted by the University of New Hampshire over a three-year period found that moose calves suffered a 70 percent death rate as a result of winter ticks.

 

At this time of year, when moose are at their most vulnerable, adult female ticks living on them, most of which are gravid (the ticks), indulge in a “blood meal” that is unlike any of the meals that they take at any other stage of life. They feed for days, swelling to ten times their normal size before dropping to the ground and laying hundreds of eggs.  The snow where a tick-infested moose has laid down is often spotted with blood and engorged female ticks. It may be of some comfort to know that Winter Ticks rarely bite and feed on humans. (Photo: A moose calf that had been walking along a packed snowmobile trail laid down , leaving spots of blood from tick bites and many 1/2″-long engorged and egg-filled female ticks.)  Thanks to Kit Emery for photo op.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com  and click on the yellow “donate” button.


Pileated Woodpecker’s Winter (and early spring) Diet

The mainstay (up to 60%) of a Pileated Woodpecker’s diet is Carpenter Ants (especially in the winter) with wood-boring beetle larvae (early spring) not far behind.  Flies, caterpillars, grasshoppers, termites, cockroaches and a variety of other insects are also consumed in summer.  However, these woodpeckers are not strictly insectivores.  During the fall and winter they seek out fruit (and nuts), including the fruit of Wild Grape, Virginia Creeper, Poison Ivy, Poison Sumac, American Holly, Elderberry, Blackberry, Raspberry, Hackberry and Crab Apple (pictured).  Roughly one-quarter of a Pileated Woodpecker’s diet may be fruits and nuts.  (Thanks to Sadie Brown for photo op.)

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com  and click on the yellow “donate” button.


Monarchs Starting To Leave Mexico

The Monarchs’ migration north has begun! We are not the only part of the world that is experiencing unusually high temperatures — there has been a heat wave in Mexico this spring where the Monarchs overwinter, and it has them on the move, leaving their sanctuaries and beginning the more than 2,000 mile journey to New England.

This overwintering generation of Monarchs lays eggs in northern Mexico and southern U.S. and then dies.  When their eggs hatch and develop into adults, usually by late April to early June, they continue the journey north that their parents began, laying eggs along the way.  They begin to arrive in northern U. S. and southern Canada in late May.

To follow their progress northward, go to Journey North’s site, https://maps.journeynorth.org/map/?year=2020&map=monarch-adult-first.  Although we probably won’t see any Monarchs in New England until the end of May at the earliest, it’s fun to be able to see exactly how far they have gotten as spring progresses.  Journey North citizen scientists also monitor mammals, amphibians and birds.  To participate in their research or to see their observations go to https://journeynorth.org/.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com  and click on the yellow “donate” button.


Male Eastern Chipmunks Exploring Female Territories

Eastern Chipmunks breed twice a year, in March and in June.  If you’ve seen a chipmunk this spring, chances are it was a male, as males emerge several weeks before females.   When they first come above ground, males check out female territories.  When females appear they soon come into estrus, which lasts for roughly a week.  However, they are only receptive to males for about a seven-hour period during this week.  Outside of these seven hours, females will aggressively repel any advances.  When males sense that their timing is right, they indicate their interest and intention by waving their tail up and down.  This only occurs during the mating season – at all other times chipmunks only wave their tail horizontally back and forth!

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com  and click on the yellow “donate” button.


Snowy Owls Starting Their Return To The Arctic

Every year in North America some Snowy Owls migrate southward during Arctic winters while some remain in the Arctic.  (In some winters — not this one — we see large numbers, or irruptions, of young owls in the Northeast which is thought to be a result of food and weather conditions further north.)  Individuals that spend the winter in New England usually can be found near large, open terrain that resembles their Arctic breeding grounds. Agricultural fields, coastal dunes and airports provide them with an ample diet of small mammals and birds.  Overwintering Snowy Owls begin to head northward in March and April. Occasionally a few owls linger on wintering grounds well into spring and summer (records of Snowy Owls exist in May in Massachusetts and June in New Hampshire).

Much has been learned about the migratory flights of Snowy Owls due to satellite tracking. According to Birds of North America, in February 2012, a transmitter attached to a female at Logan Airport in Boston, MA tracked an owl to Nunavut, Canada. The owl migrated north along Hudson Bay’s eastern shore during spring migration and returned south along Hudson Bay’s western shore during the autumn migration. It eventually returned to Logan Airport the following November, having completed a 7,000 mile round trip.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com  and click on the yellow “donate” button.


American Basswood Fruits

American Basswood (Tilia americana) is known for the alluring scent and abundant nectar of its flowers, as well as its lightweight, odorless wood which lends itself to the production of food crates and boxes, musical instrument parts, yard sticks and cabinets.  Equally distinctive are the nutlets that are borne on a stem bearing a persistent bract, or modified leaf, that aids in the wind dispersal of the fruit.

Most of the nutlets are eaten in the fall by chipmunks, mice, squirrels, porcupines and rabbits, but some persist until winter winds detach them from the tree and they fall to the ground. Basswood trees are not as dependent on seed germination as many other species due to their ability to put out new shoots from their stump or roots if cut down or damaged (self-coppicing).

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com  and click on the yellow “donate” button.


Striped Skunks Mating

A very high percentage (96%) of female Striped Skunks become pregnant each breeding season.  Both males and females are covering a lot of ground this time of year (up to 2 ½ miles per night), visiting each other’s dens in search of a mate.  While male skunks are promiscuous, mating with as many females in their territory as they can, females mate once and fight off any further attempts from other males.

Unlike primates, who experience “spontaneous ovulation” and ovulate midway through their menstrual cycle, female Striped Skunks, along with cats, ferrets, and rabbits, are what is known as “induced ovulators” – the act of copulation stimulates ovulation, which doesn’t occur until copulation has taken place.

Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com  and click on the yellow “donate” button.