Wednesday, November 6, 2013

Eastern Comma Butterfly

Today I had an encounter with another overwintering butterfly -- the Eastern Comma (Polygonia comma). After several cool days, this Eastern Comma is taking advantage of today's sunny 58 degree weather and warming itself on my back deck.  Like the Mourning Cloak, this butterfly will hide from the harsh winter elements under tree bark or in various cavities.  At the first hint of spring warmth, it will emerge to bask in the sunshine and lay its first brood.  These butterflies are quite feisty and are known to fly at other butterflies and insects that invade their territory.   Host plants for their caterpillars include nettles, American elm, and hops.

Overwintering Mourning Cloak

I turned over this chunk of wood while hiking recently, not expecting to find much of anything as the cold weather has already set in.  

Instead, I was pleasantly surprised to discover a mourning cloak butterfly (Nymphalis antiopa). 

It's so well camouflaged that the edges of its wings are barely noticeable against the wood.

While most butterflies migrate or overwinter as eggs, larva or pupae, adult mourning cloaks find a spot under tree bark, in a hollow or another suitable crevice such as eaves of a house, where they remain through the winter in a state of diapause.  Like other creatures that overwinter, mourning cloaks are able to keep from freezing by building up glycerol, an "anti-freeze" in their bodies while also lowering their metabolic rate. It's amazing that such a fragile looking creature can withstand the fury of winter.  By overwintering, mourning cloaks gain by being the first butterflies of spring.  They may be seen drinking tree sap.  The females will lay eggs on host trees - birches, poplars and elms.

Wednesday, April 3, 2013

Ring-necked ducks

Just recently, ring-necked ducks (Aythya collaris) arrived at Baker's Meadow.  There are about five male/female pairs swimming about in the deeper parts of the pond.  They've come from warmer southern wintering grounds.  They are just stopping over on their way north to breed.  Unlike the dabbling mallards, ring-necked ducks can be seen diving underwater.  There's plenty of food here for them - lots of insect larvae, freshwater clams, and aquatic vegetation.  From a distance, the males appear black with a white ring at the base and near the tip of their beak.  In reality, their heads are overlaid with irridescent purple. The females are brown with a white beak ring.  The "ring neck" in their name comes from a dark brown ring around the male's neck which is difficult to see from a distance.  Look closely and you can see the ring in the photo below.

Both have gold colored eyes, but the female also sports a white eye ring.

The ring-necked ducks must share the pond with quite a few bossy Canada geese.  Lucky for them, the mute swans seem to be absent.

Monday, February 4, 2013

Calvert Cliffs State Park, Maryland

The final destination in Maryland was Calvert Cliffs State Park in Lusby on the Chesapeake Bay. 

The 1.8 mile hike to the water was easy and scenic, with plenty of wildlife and varying habitat.
Can you spot the two fence lizards -- one gray and the other brown with a blue underside -- in the center of the photo?  They were having a territorial skirmish just outside the parking area.
A red-tailed hawk waited patiently for a meal to appear near the trail.
Turtles basked along logs in the marsh.

Too bad this boardwalk was closed for repairs.
Northern cricket frogs of varying colors bounced around the water's edge and along the sides of the trail.


A zebra swallowtail flitted from flower to flower.
This watersnake was weaving its way through the dense shrubs along the waterside edge of the trail. We met a ranger along the way who mentioned seeing a cottonmouth earlier that day.
A five lined skink zipped up, down and around a tree.
Finally, the trail opened up onto the beach and the fossil hunting began.
What we found:

A shell fragment of Chesapecten nefrens - an ancient scallop.
Snaggletooth shark teeth
Tiger shark tooth
Lemon shark teeth
Ray dental plates
A sand tiger shark tooth
A piece of a megalodon tooth
A gray (or requiem) shark tooth
A nearly complete megalodon tooth
Even on the way back to the hotel, we spotted this osprey near its nest on a platform near the side of the road.
A great day of hiking, nature watching and fossil hunting.


Fossils from Maryland (Miocene)

Next we drove to Brownies beach in Bayfront park on the Chesapeake Bay. There we found fossilized shark teeth, vertebra, and dental plates from the Miocene epoch.

A shark or other fish vertebra

Lemon shark teeth

Tiger shark teeth

Sand tiger shark teeth

Gray or Requiem shark tooth

Snaggletooth shark tooth

Ray dental plates

Staying on Chesapeake Bay, we headed to Matoaka cottages. We were hoping to get our hands on the elusive megalodon tooth, but it wasn't our lucky day. It was a disappointing hunt although there were a couple of new fossils we hadn't yet collected.

Astrhelia coral

Crab claw fragment
Marine mammal rib fragments

ray dental plate
Gray shark tooth
snaggletooth shark tooth
Turritella snail shell