A long reach...

Deep snow can make winter survival difficult for white-tailed deer.  Getting around is difficult and requires more energy.  Most of the food sources are inaccessible, especially if the snow is combined with a layer of ice that prevents deer from digging down to the ground.

Because foods such as grasses, forbs, and nuts are often unavailable, deer survive mostly on a diet of browse (buds, leaves, branch tips) during the winter months.  Where deer populations are heavy, all the food that is easy to reach is already gone by this time of winter.  Sometimes the only food left available in area is high overhead.  It is not unusual to see where deer have browsed as high as eight feet off the ground by standing on their hind legs.

I retrieved my trail cameras this afternoon and was lucky enough that one of the cameras had recorded this behavior.  The deer in this series of images is reaching up to eat needles from an Eastern Hemlock (Tsuga canadensis).

Normally I just change out the memory cards in my trail cameras and leave the cameras in the woods, but I decided to remove the cameras completely for now.  Even though its in a public park, the area that I place the cameras is quite secluded when the ground is not frozen - it's in the middle of a swamp.  However, right now its easy to access because everything is frozen over.  I also left a trail of footprints directly to the camera sites.  I also recorded a person on one of the cameras.  This is not the first time I have ever seen a person on one of the cameras, but it was the first time I could tell that they knew the camera was there.  Fortunately, they only smiled at the camera and left it in place.

If this you - Thank you for being an honest person!

Native Specie Profile - White-breasted Nuthatch

White-breasted Nuthatch

 
One of the most widespread birds in the United States is the White-breasted Nuthatch (Sitta carolinensis).  This species is found in portions of every state except Alaska and Hawaii.  It also ranges north into southern Canada and south through much of central Mexico.  Never found far from trees, the White-breasted Nuthatch prefers wooded habitats, especially deciduous forests.  It is also frequently found in parks, yards, and suburban areas with mature trees.  Three other Nuthatch species can be found in the United States, but of the three only the Red-breasted Nuthatch (S. canadensis) is also found in mid-Michigan.

The White-breasted Nuthatch is a small bird.  An adult White-breasted Nuthatch measures about 5 - 5.5 inches (13 - 14 cm) from beak to tail, with a an 8 - 10.5 inch (20 -27 cm) wingspan.  They weigh between 0.6 and 1.1 ounces (18 - 30 grams) or about as much as 3 to 5 quarters.

This species has a blue-grey back and wings, accented with black, and a white breast and belly.  The outer feathers of its tail are white, but only noticed when tail feathers are fanned.  Another interesting feature that you don't always notice is the patch chestnut colored feathers on its belly and flank.  Males and females can be identified by the color of their "cap".  Males have a black cap and females grey as seen in the photos below.  The nuthatch's beak is strong and straight or slightly upturned. 

Although White-breasted Nuthatches have a strong beak they rarely excavate their own nest holes.  Instead they will use abandoned woodpecker holes or natural cavities in trees.  This species will use artificial nest boxes; I have had a pair nest a few feet away from a window in a nest box that I had placed.  Their nest consists of a cup made of fine grasses, shredded bark, feathers, and other soft materials.

Female White-breasted Nuthatch - not grey cap and elongated rear toe (hallux)

White-breasted Nuthatches are omnivores.  They consume a composed mostly of insects, insect larvae, and other invertebrates such as spiders, but will also readily eat seeds and nuts.  They visit feeders readily and consume both seeds (especially sunflower seeds and peanuts) and suet.  In the wild, White-breasted Nuthatches often forage in mixed flocks with other nuthatches, chickadees, titmice, and small woodpeckers.

Female White-breasted Nuthatch - Its unique downward foraging method allows it to find food other birds overlook 

Nuthatches have a unique foraging strategy that is not employed by other birds in mid-Michigan; they can walk head down on a tree trunk.  Many birds such as woodpeckers and Brown Creepers (Certhia americana) forage by climbing up a trunk poking their bees into cracks and crevices in the bark.  It is thought that the nuthatches method allows them to find food that has been overlooked by these species.

Why can nuthatches climb face-down, but other birds can't?  It has to do with their toes.  Nuthatches have four toes on each foot; three face forward and one faces backwards.  This backward facing toe is known as the hallux.  On nuthatches the hallux is elongated and has a strong curved nail.  The three forward facing toes, although shorter, also have strong curved nails.  This combination allows the nuthatch to grip in such a way as to allow it to walk facedown on a tree trunk.  It is our only native bird that is capable of such motion.

Male White-breasted Nuthatch - note black cap.

White-breasted Nuthatches are usually found in pairs.  A male and female will remain together year-round and aggressively chase other nuthatches out of their territory.  The male and female shown in the two pictures directly above were photographed a few feet from each other on the same tree.

Basic Information

White-breasted Nuthatch

Sitta carolinensis

Size: 5.0 - 5.5" long

         8.0 - 10.5" wingspan

Habitat: woodlands, woodland edges, parks, suburban areas

Eats: insects, insect larvae, spiders, seeds, nuts

Nest: in natural cavities in trees, abandoned woodpecker nests; a cup made of grass, shredded bark, feathers, other soft materials; will nest in artificial nest boxes

Let's twist again...

I spent most of yesterday at the Little Salt River Park in Shepherd.  My reason for being at the park was to collect aquatic invertebrates with 5th grade students from Shepherd Elementary.  I worked with one class in the morning and a second class in the afternoon with a hour-long break for lunch.  While I was waiting for the second class to arrive I tried photographing some of the Barn Swallows that were swooping low over the river to catch flying insects.  Many of these insects were the adult form of insects that students were trying to catch in the water. 

Photographing individual swallows in flight is not impossible, but it is not easy.  Most photos that you see of flying swallows are probably taken either as the swallow slows down to approach a nest or shot using some sort of automatic trigger on a camera.  I was trying to follow the birds with my camera as they swooped low over the river.

My success rate was not very high. 

The photos could have been better if it had been a sunny day.  The photo with the clearest focus on the swallow was this one in which swallow has almost exited the frame of the photo - chopping off its head.

My favorite picture is this one.  The swallow is just an inch or two above the surface of the water, but that's not why I like this picture.

If you look closer you can see some of the incredible flexibility of the swallow as it executes a turn.  As you looked at the other photos above you might have noticed that the upper surfaces of a Barn Swallow's back and tail are a solid dark blue.  In this photo you can see the lower surface of the tail and the upper surface of the back and wings. 

Basically this bird has twisted at the hips/waist to change direction.  It's hips are rotated as much as 120 degrees- 1/3 of the way around.  It's this flexibility that allows swallows to change direction almost instantly while in flight.  It's pretty amazing adaptation that allows swallows to feed almost exclusively on flying insects.

Adaptations - Mobbing

Have you ever observed small birds harassing or diving after a much larger bird?

Then you have witnessed a behavioral adaptation known as mobbing.  Adaptations are physical traits or behaviors that helps an organism survive in its habitat.  Mobbing is a behavior that birds use to chase away predators.  When mobbing small birds will often gang up on their target.  The idea is that although a predator might be able to catch a single small bird diving after it, the predator will be overwhelmed by sheer numbers and leave to avoid further harassment. 

Why are small birds acting this way?  The answer depends.  Sometimes small birds become more aggressive (and territorial) during mating season and they will chase away any bird that flies over their territory.  Birds also use mobbing to protect themselves and their young from predators.  When young birds are still in the nest adult birds will often fly after any large bird that strays "too close" to the nest.  This "too close" distance is arbitrary and a bird may chase a predator hundreds of yards if feeling particularly feisty.  Mammals (including people) are also lumped into this danger category - walk too close to a Red-winged Blackbird nest and you are likely to be mobbed.

Small  birds don't discriminate.  Besides people, mobbing targets include hawks, eagles, owls, herons, and crows.  Crows themselves will often mob hawks and owls.  Did you ever wonder why owls are camouflaged?  You would be too if you had to avoid being mobbed all day when you just want to sleep!

The large poplar trees outside our office are the frequent perch of a pair of Red-tailed Hawks (Buteo jamaicensis).  I am often alerted to the presence of the hawks by the sounds of mobbing birds.  Last week it was a pair of Blue Jays (Cyanocitta cristata). 

 
The jays took turns diving on the hawk.  I don't think they ever made contact, but the hawk kept having to duck to avoid the jays.

After several minutes, the hawk had enough and flew away pursued by the jays.

A Sign of Spring? - American Robin

Every year, someone will call the local newspaper to declare that Spring has arrived - they have seen the first American Robin!

But, is the American Robin (Turdus migratorius) really a good indicator of the arrival of Spring?

The answer is maybe.  It depends on where you live.

Adaptations - Stratification

Wild Leek waiting out the winter months

A simple definition of the word adaptation is a physical trait or behavior that helps a living organism survive in its habitat.  Every living organism has adaptations.  Physical adaptations are easy to see - think the spots on a fawn or the thorns on a rosebush.  In animals behavioral adaptations can be easy to observe, such as hibernation during periods of extreme cold or heat.  Behavioral adaptations in plants are more difficult to recognize.

One behavioral adaptation that can be observed is stratification.  While some seeds of some plants are capable of germinating immediately upon maturation, for other species this would be less than ideal.  For instance, early germination might mean that a plant begins to grow at the wrong time of the year.  A plant that requires 90 days of warm weather to grow and develop flowers and seeds would not want to sprout and begin growing in September when it will be killed by cold within weeks.

Instead, many seeds experience a period of dormancy once they mature.  Stratification is an adaptation that allows the seeds to break that period of dormancy and then sprout.  Many seeds require a period of cold stratification.  This means that they must experience an extended period of cold temperatures before they will come out of dormancy.  One good example of a plant that goes through cold stratification is Common Milkweed.  I have planted milkweed seeds in spring that did not undergo stratification.  Rather than sprouting, they remained in the ground dormant all summer before finally sprouting the following spring (after a winter in the ground).  Many summer and fall wildflowers require this type of stratification.

Common Milkweed seeds need to undergo cold stratification before they can sprout.

Other wildflowers require a more complex hot-cold stratification, requiring a long period of warm weather followed by a period of cold weather.  Many spring wildflowers such as Bloodroot (Sanguinaria canadensis) fit in this category.  Other species such as Wild Leek (Allium tricoccum) require a multi-year hot-cold-hot-cold stratification process.  All of these different stratification requirements can be very frustrating when trying to start a wildflower garden from seed.

What's this bug? - Locust Borer

One of the common features of my job is that people are always asking me to identify things they have found in the wild.  If someone walks into the office carrying a jar, I can be assured that I am going to be asked to identify an insect.  I am not an professional entomologist (someone who studies insects), but I try to help if I can.  With that in mind, I am going to start a semi-regular feature of this blog on insect identification.

So... What's this bug?

Locust Borers exhibit a type of mimicry known as Batesian mimicry.  This means that they are harmless, but look like something dangerous (such as a wasp)

First of all, the animal pictured is a beetle not a "bug".  Both beetles and bugs are insects - animals with an exoskeleton, three body segments (head/thorax/abdomen), and six legs.  Bugs are a certain type of insect (shield shaped body, wings that cross over to form an x-shaped pattern while at rest, and a piercing mouth used for sucking juices), but the word "bug" is often used to mean any insect regardless of species.  Unlike bugs, beetles have a mouth designed for chewing.  Beetles have two pairs of wings, but the outer pair of wings have hardened into a protective covering for the soft inner pair.  This hard outer pair of wings is known as elytra (singular is elytron).

So we have established that this insect is a beetle, but which one?

Specifically, it is a Locust Borer (Megacyllene robiniae).

Locust Borer feeding on goldenrod pollen.

Locust Borers are named because their larvae bore (tunnel) into and through the wood of Black Locust (Robinia pseudoacacia) trees.  In small Black Locust trees this tunneling may actually kill the tree.  The adult can be found in the fall feeding on pollen, especially goldenrod pollen.

The tree and beetle are probably not native to Michigan.  The tree was introduced in the 1800s and often grown for use as fence posts due to its natural rot resistance.  The beetle was likely introduced at the same time.

With its yellow and black color scheme, the Locust Borer is easy to see.  This might seem like it would be a bad thing.  It's easy to see so birds and other predators should be able to pick it off.  Instead these colors act as a form of protection.  By mimicking the color pattern of bees and wasps, this harmless beetle is protected from animals that would be wary of a wasp's sting.  This type of mimicry is known as Batesian mimicry.

Nothing significant

Frost damage on Skunk Cabbage plants

 This picture shows how Skunk Cabbage (Symplocarpus foetidus) plants should look right now.
 

 

The next picture shows how they actually looked yesterday morning.

Several nights of heavy frost have badly damaged the leaves of the plants.  Hopefully they can recover.
 

It amazing to me that the plant's flowers can melt snow due to the metabolic heat that they generate,

but the leaves can be damaged by a few hours of freezing temperatures.

Spruce Pollen

When I arrived at work this morning I noticed an American Robin (Turdus migratorius) fly into one of the spruce trees that line our parking lot.  As the robin disappeared into the tree a cloud of dust appeared.

Was the robin a magician using smoke to distract its audience?

No.

The spruce tree was heavily laden with pollen and the impact of the robin caused a pollen release.

A close examination revealed that the lower branched of the spruce trees are covered with male cones.  Male cones produce pollen and then fall off the tree once their job is done.

These male cones release pollen in huge quantities any time they are disturbed.  That disturbance could be a bird, the wind, or someone (me) hitting the branches with a stick to trigger the release of pollen.

First up is a native White Spruce (Picea glauca).

And here is a non-native, but commonly planted, Norway Spruce (Picea abies)

For good measure, I took a number of still photographs of the pollen as it was released.  The first picture shows the exact instant the stick hits the branch (of a White Spruce) and the whole sequence took less than 1 second to photograph.

 

 

The goal of all of this pollen is to float through the air and find a female cone.  Usually spruce trees have their male cones on lower branches and their female cones near the top of the tree.  This is to avoid self-pollination.  Although spruce trees can self-pollinate.  It is preferable that they exchange genetic information with other trees.


With this much pollen flying around, it's no wonder that my allergies are bothering me.

Sedges are habitat forming...

In the lowland area at Mission Creek Woodland Park there is an area of northern hardwood swamp with a canopy of mostly Red Maple (Acer rubrum) trees.  The floor of this swamp is dominated in part by tussocks of sedge (Carex spp.).

I love photographing these tussocks- they are just so photogenic.

Besides their obvious photographic value, they do serve other functions.  Once these tussocks are established, they serve as a habitat for other plants.  If you look in the picture below, you should notice stalks projecting from many of the tussocks.  Most of these stalks belong to Rough-leaved Goldenrod plants.  The goldenrod plants would probably drown if they tried to grow directly in the water of the swamp, but the sedges have provided little micro-habitats that elevate the goldenrod above the water and allow them to grow.

Many of the Red Maple trees in this swamp also started their life on the tussocks.  Seeds that were lucky enough to land on a tussock found conditions just right for growth - rich soil, just enough moisture, and warmth (the green tussocks warm up in the sunlight and are warmer than the surrounding soil and water).  Eventually some of these trees may grow to adulthood.

Stand Back!

Sometimes it is okay to touch fuzzy things.

Common mullein leaves are soft and fuzzy

Sometimes it is not okay.

Hickory Tussock moth caterpillars look soft and fuzzy but are not!

The Hickory Tussock Moth caterpillar (Lophocampa caryae) is covered with both long and short hairs.  Be careful of both.  The short hairs are barbed and will break off in your skin, causing your skin to itch.  The long hairs (sometimes called lashes) are hollow and connected to poison glands.  If you touch one of these, the hollow hairs will pierce your skin and introduce the poison into your body!  It quickly causes an itch burning sensation that is similar to sting of a nettle.  Some people can have severe reactions that may require a visit to their doctor.  The black and white color scheme is there to warm predators including humans to stay away.  This use of warning colors is known as aposematic coloration. 

If you accidentally (or intentionally) touch a Hickory Tussock Moth caterpillar,  you will quickly learn to associate aposematic coloration with danger or pain and you are less likely to make the same mistake again.

Stinging caterpillars!  Isn't nature cool?!