Sunday, March 31, 2013

Karner Blue Butterfly

Karner Blue Butterfly
The Karner blue butterfly is one of nine species of butterflies on the North American Endangered Species List. Lycaeides melissa samuelis is a subspecies of the Melissa blue butterfly. The Melissa blue is found in the western half of North America where the Karner subspecies is found in the Great Lakes Region. The reason why the Karner blue has decreased in population is because it is very specific in the larval host food. The Melissa blue caterpillar feeds on various plants in the pea family. The Karner blue caterpillar feeds only on lupine which because of habitat loss and fire prevention has been decreasing in the Karner blue's natural habitat. As the larval host plant declines there is less food for the Karner caterpillars and so their population declines too. Fortunately there are still some places where the Karners thrive. This photo was taken at the Necedah NWR in Wisconsin. Necedah has one of the highest known Karner populations around, including this pair that was doing their part to increase the species population.

Thursday, March 28, 2013

Hawaiin Beach

When we went to Hawaii back in 2002 I took quite a few beach shots that some how always make me think of Microsoft screen savers.

Wednesday, March 27, 2013

Great Horned Owl Chicks

This is the time of the year when great horned owl chicks are starting to leave the nest. Some of the early hatches may be fledging but most are just starting the branching stage. Prior to fledging the young owls will climb around on the tree branches around the nest. This is called branching. At The Raptor Center we see a lot of baby owls at this time of year as some of the branching owls end up on the ground. The best thing for the owls is to go back to the nest, so after a quick examination to make sure they are not injured they are returned home. 

Tuesday, March 26, 2013


 The kestrel is a small raptor in the falcon family. There are different species of kestrels found around the world. They include the common kestrel in Eurasia, Nankeen kestrel in Australia, grey kestrels in Africa, the American kestrel in the Americas, as well as several other species. Like other falcons the kestrel is designed for quick flight and maneuverability. Kestrels will eat small birds, like other falcons, but will also eat small rodents and large insects. They often hunt by hovering in place over a field while they search for prey.
Kestrels are in the small group of raptors where males and females can be distinguished by their coloration. Like most other raptors the female kestrel is larger then her male counterpart but her coloration is much more muted and earthy. This is a defense mechanism for when the female is on the nest incubating her eggs. since it is smaller then many other raptors the kestrel is often on the other side of the predator/prey relationship. Her brown striped pattern is camouflage that helps her blend in with the sticks around her nest. The male does not help with incubating the eggs and so it is not necessarily for him to be as inconspicuous. As you can see from the top photo the males are much more brightly colored.

Monday, March 25, 2013

Hanauma Bay

 Hanauma Bay is a park located east of Honolulu an the Hawaiian Island of O'ahu. The bay was formed when one side of an extinct volcano collapsed allowing sea water to flood in and fill the cone. The bay was purchased from a private estate back in the early 1900's. In the 1930's the road that leads past the bay was paved making it more accessible, however after the attack on Pearl Harbor in 1941 the bay was closed.
 After the war Hanauma Bay was reopened and became more popular then ever. In 1956 parts of the coral reef in the bay were cleared with dynamite to lay telephone cables linking Hawaii to the mainland. This and other changes in the 1970's opened up room for swimming. By the 1980's the number of people visiting the beach each year was in the millions. Visitors, who often did not know any better, were walking on the reef, trampling coral and algae, and littering. The water in the bay was filled suntan oil and other chemicals. This abuse destroyed the colorful coral of the bay and left behind a dead , blackened reef.
Fortunately thing have gotten better. Visitor numbers are limited to help prevent over crowding on the beach. The park is closed one day a week to give the wildlife a break from nosy tourists. A marine education center was erected in 2002 to help educate the public about the flora, fauna, and habitat.  New visitors are required to watch a short film about conservation of the bay. Tin order to reflect the change in priorities the name was changed from Hanauma Bay Beach Park to Hanauma Bay Nature Preserve. Sea life has returned and has begun to thrive again and new live coral has begun to grow, second photo.

Sunday, March 24, 2013

The Short Life of the Spiny-backed Orbweaver

Spiny-backed Orbweaver
 Gatteracantha cancriformis is a species of genus Gatteracanha, spiny-back orbweavers, found in North, Central and South America. It is found in wooded area in tropic and subtropic climates. In the U.S. it is found across the south from California to Florida. It is easy to identify through the crablike shape of the abdomen and the spines that line it. Though it may look like a crab it is not in the same family as crab spiders are. These are a part of the orbweaver family which are spiders that spin intricate orb spaped webs which they use to catch their prey.   
Spiny-backed Orbweaver
These spiders can come in several different color patterns. They are usually mainly white or yellow in color with black spots. The spines on the white variety can be either black, as the one above, or red. The yellow version always has black spines. The color pattern underneath is quite different as you can see in the second photo. This is a female spider. It is easy to tell because like most spiders the female is much larger then the male. as a female she will have a longer life then her male counter part. The male spider will die shortly after mating. This usually occurs only about 3 months after they hatch. The female does not live much longer. She will die after laying her eggs.

Saturday, March 23, 2013

Long-billed Thrasher

Long-billed Thrasher
The long-billed thrasher is a robin sized bird that is found in the dense scrub of southeastern Texas and eastern Mexico. It is usually seen foraging low in the scrub or on the ground where it tosses aside leaves and sticks looking for insects to eat. The long-billed thrasher looks similar to the more common brown thrasher, some of which winter in the same territory as the long-billed thrasher. The long-billed thrasher is slightly larger and has a beak that is a bit longer. An easier way to tell the difference between the two is to look at the undertail coverts if possible. The long-billed thrasher has streaks running down the undertail coverts where the brown thrashers are clear.

Friday, March 22, 2013


Symmetry comes from the Greek word symmetrein which roughly translates as "to measure together". One of the most basic forms of symmetry is mirror or line symmetry. In a two dimensional figure, like the photo above, there is a a line that forms an axis of symmetry. On each side of this line there are matching points which are the same distance from the line, or axis of symmetry. So with water the axis of symmetry is the surface of the water. The points of the reflection are the same distance from the surface of the water as the identical points on the log. This is not a perfect example of mirror symmetry though because the water, and the ripple running through it, slightly distort the image.

Thursday, March 21, 2013

Spring is Here?

 Yesterday was the first day of spring but if you were here in Minnesota you might not think so. We still have loads of snow and windchill temps that are going down below zero. While I am certainly ready for spring, and tired of shoveling snow a long winter is not all bad. When we have a late winter the trees will often not leaf out until the middle of May. Trees that do not have their leaves yet lead to much better warbler photographing when the warblers migrate through usually at the beginning of May. Long winter usually also lead to better photo opportunities in Yellowstone, where we will be traveling shortly. With the higher elevations still locked up in snow the animals usually head to the lower elevations which are closer to the roads. Both trips where we have seen wolf up close were years that we had a late winter. We also see many more grizzly and other animals.
 Now last year was quite different. I took this picture in a park last year on March 24th. There are no flowers or bugs around yet this year, at least not outside. What a difference!

Tuesday, March 19, 2013

Julia Butterfly

Julia Butterfly
The Julia butterfly, or Julia heliconian is a brushfoot butterfly that is found from Brazil to the southern parts of Texas and Florida. Like many tropical butterflies it is bright in color and feeds of the nectar of various flowers. I photographed this butterfly down in south Florida. The larval host plant of the Julia are various passion vines.

Red-shouldered Hawk

Red-shouldered Hawk
The red-shouldered hawk is a medium sized Buteo found primarily in the eastern half of the United States. There are several subspecies of red-shouldered that differ by coloration, size and geography. The norther red-shoulders that we see here in Minnesota are a bit larger and dark. They look similar to a red-taled hawk but they are not as stocky and their breast is usually pretty orange. This subspecies migrates to Mexico for the winter. The red-shouldered subspecies that is found in Florida, like the one above, is much lighter and color as well as a bit smaller. They are much more common down in south Florida. Every time we have visited we saw more red-shouldered then we did red-tailed hawk. They are much more uncommon here in Minnesota. There is also one subspecies that is found along the California coast far away from any of the other subspecies of red-shouldered hawk.

Monday, March 18, 2013

Heron Rookery

Heron Rookery
 St Patrick's Day was a reminder in the past that it was time to start watching for great blue herons at the rookery at the North Mississippi Regional Park. The herons typically began to arrive the a day or two after St Patrick's day. The males were usually the first to arrive. They would claim a nest and then wait for a female to arrive.
Great Blue Heron
If a female liked a male heron's nest then the mating ritual would begin. The male would grab sticks from the trees on the island or from trees along the shore and bring them back to the nest. At the nest there was a ritual that the birds would perform, an almost intertwining of their long necks, with the male up high passing the stick and the female below accepting it. Then he would fly off to find another gift while she would use the stick to remodel the nest to her liking. Eventually this ritual would often lead to copulation and if the birds were lucky eggs. Unfortunately the summer after I took these photos a tornado hit the rookery destroying all of the nests and knocking over half of the trees. Last year I checked and none of the herons returned to the island. Most had probably moved on to less photographer accessible rookeries. But I keep checking and hoping that one day they will return.

Sunday, March 17, 2013

Dragonfly Eyes

Cobra Clubtail Macro
Dragonflies have amazing eyesight. Their compound eyes are made up up to 30,000 different facets called ommatidia. Each ommatidia is made up of lenses that are attached to sensory cells. Since the facets are pointing in multiple directions the dragonfly has almost a 360 degree field of vision. Besides an expanded field of vision the dragonflies compound eyes can see into the ultraviolet spectrum, detect the plane of polarization of light with out sunglasses, and process movement faster then we can. I guess that when you are mostly devoid of other scenes your prevailing sense, in this case sight, evolves and becomes enhanced.  

Sandhill Cranes at Sunset

Sandhill Cranes at Sunset

Saturday, March 16, 2013

Bird Bathing

Yellow Warbler Bathing
 In some ways birds are just like people. Like most of us hygiene is important to the birds. During a typical day, dirt and other debris can collect up on the feathers of a bird. This can affect their ability to fly properly. So to rectify this issue birds frequently bathe. Besides cleaning the feathers of dirt bathing can also help eliminate excess preening oils and help control parasites. Usually the bird will spread out its feathers to allow the water to get underneath and wash off any dry skin underneath.
Yellow Warbler Bathing
There are a number of different ways that birds bathe. Birds with strong feet wade into the water, partially submerge themselves, spread their wings and roll back and forth. They will also submerge their head and through it back to help get water on to their back. That is how this yellow warbler bathes. Birds with weaker legs, like swallows, will just skim across the water, taking a shower as they fly. Most woodpeckers bathe by spreading their wings and feathers when it is lightly raining or misting. In areas where their is little water birds will take a dust bathe. They role around in a patch of dirt or sand. The fine dust that they bathe in collects the  larger dirt and oils from their feathers and makes it easier to remove through rigorous shaking. During the winter birds typically do not bathe as often, but it is still necessary for them to bathe when they can. Often times they will bathe in snow melt or they will sometimes bathe in the snow itself. They use the snow similarly to how they would use dirt in a dirt bathe. They dig, role and throw the snow on themselves. When the snow melts the liquid washes away all of the excess gunk and the bird is clean again.