Thursday, March 28, 2013

Galápagos Tortoises

Young captive Galápagos Tortoise, Geochelone elephantophus
The Galápagos Tortoises are the world's largest tortoises, and possibly one of the most endangered species. Of the estimated 15 subspecies since Darwin's first encounter, only 11 now remain. The main impact came from hunting between the 17th and 19th centuries. As a docile species with no predators, and an ability to go long without food or water, they became common sources of meat for sailors. These tortoises are now protected from hunting, but nonnative feral species pose equal threat to these tortoises and their eggs. Although still at high risk, the Ecuadorian government strictly regulates visits to the Galápagos National Park, and many facilities are trying to maintain a population either in captivity or for possibly future release.

Treats of apples and carrots, diet of grasses, cactus, leaves.
A commonly known characteristic of the Galápagos tortoises besides size is longevity. Turtles in general are a long-lived species with smaller turtles reaching an average of 50 years, and up to 80 years. The Galápagos tortoise easily reaches ages over 100, with current records showing one almost reaching 200 years. Due to the length of time, an exact average age is unavailable. The male of the larger subspecies can easily reach over 200 kg (450 lbs) and grow to just under 2 m (6 ft) in length. The shells are either classified as saddle-backed or dome-shaped. In areas with more ground vegetation, dome-shaped are common. In areas with less ground vegetation, the saddle-backed shape is common as it allows a higher neck extension. With more successful breeding programs such as at the Darwin Research Station, there is still a chance of saving some of these subspecies from extinction.

Tuesday, March 26, 2013

Texas Winter Weather

Snowing in North Texas (A Rare White Christmas)
Texas weather is notorious for its day to day variability. On average, the first freeze arrives November 22nd and the last freeze March 13th. While these past two days are abnormal for their past average last freeze date, it is not unheard of by any means. Of the past ten last freezes recorded in the Dallas-Fort Worth Metroplex, they have all occurred in the month of April, the latest occurring April 13th in 1957 and 1997, respectively. On the other hand, the earliest last freeze has occurred as early as February 5th in 2000.

In looking at records, there has never been a freeze the past two centuries to break the 1898 record of October 22 (keep in mind, records do not go before 1898). Also to note the variability of Texas weather, March has seen temperatures below freezing and temperatures above 37°F (100°F) in one year. While I cannot say where past records were taken, the recent records are recorded at the DFW Airport. For this year alone, surrounding areas have seen additional freezes, but they will not be added to the record.

Busy evening so I hope this post suffices. At the least, I was finally able to use the photograph I've been wanting to use for sometime. It was taken this past December during our rare white Christmas. I'm aiming to do more like it, but have not had time recently. Expect a nice, typical make up post on Thursday!

Thursday, March 21, 2013

Common Chickweed

Common Chickweed, Stellaria media
Common Chickweed, a cool season annual, is native to Europe, but has since spread throughout most of the North American continent. The name chickweed comes from its common use as food for chickens. This plant cannot tolerate high temperature well, resulting in a growth only during the fall and winter months. While regarded as a weed, chickweed has many other uses and purposes. The seeds are food for birds, the young leaves are edible to humans, and the plant has been used for a variety of folk remedies.

As someone one told me: "Nothing is a weed, but rather a plant growing in the wrong place."

Tuesday, March 19, 2013

Carolina Chickadee

Carolina Chickadee, Poecile carolinensis
A small, easily identifiable bird, the Carolina Chickadee is a very common sight and sound at feeders and around suburban areas. The Carolina chickadee can be found year round throughout the southeastern portion of the United States. This species is a common flocking bird, but will pair off during the spring. Depending on the population, either half or most will remain a pair for several years. While they will readily use nest boxes, as secondary cavity nesters, they will also use cavities created by woodpeckers or other animals. During incubation, the female chickadee will sometimes imitate a snake to ward off predators.

Thursday, March 14, 2013


Henbit, Lamium amplexicaule
A member of the mint family Lamiaceae, Henbit, or Dead-nettle, is a common forb throughout most of the United States, but is a native of Europe and the Mediterranean. This cool season annual can reach a height of 38 cm (15 in) and contains two types of leaves: stemmed and not stemmed. Henbit is covered with fine hairs and blooms small, dark pink pitcher-like flowers. As an edible herb, young leaves of henbit have been known to be used fresh, cooked, or seeped into a tea.

I'd advise more research before deciding to try and eat this plant, but perhaps you could add some of the now blooming Eastern Redbud flowers to the meal...

Tuesday, March 12, 2013


South American Sundew, Drosera
A carnivorous plant of the Drosera genus, Sundews can be found on all continents with the exception of Antarctica. Although a preference for wet habitats such as bogs, the sundew can also be found on sandy banks and other soils poor in nitrogen and phosphorus. After ensnaring prey, the sundew curls its prey to the spoon-shaped leaves. A few species may hurl insects into the sticky dew with additional tentacles. It can take at minimum four days to digest the prey, but collectively sundews can trap over six million insects within a 0.008 km² (2 acre) area.

While this dew plays an important role in capturing prey to obtain the nutrient otherwise lacking in the soil, it also plays a role in research. The sticky, biodegradable dew is a possible candidate in the field of  tissue engineering. With its highly elastic nature and high biocompatibility, it could also prove useful for other biomedical applications.

Thursday, March 7, 2013

Snow Goose

Snow Goose, Chen caerulescens
Often seen flocking together during the winter months within the United States, the Snow Goose is a common migrant species spotted along the major flyway routes.  Not only are snow geese strong fliers, but they are remarkable swimmers and walkers. They adapt very well to use agricultural fields which have allowed population stability, but as agriculture declines in certain areas, so does the population in those areas. As a species known for its philopatry, or the tendency for individuals to exhibit a long-term use of an area, a change in local population is easy to observe; however, this is not always bad news. Goslings reared away from traditional feeding areas have a higher survival rate. This may reflect that philopatry is possibly maladaptive for snow geese at this time.

Tuesday, March 5, 2013

American White Pelican

American White Pelican, Pelecanus erythrorhynchos
One of the largest birds in North America, the American White Pelican can be seen throughout a vast portion of the continent. With the exception of a few residential populations in the south, these birds migrate starting at two years of age. The American White Pelican nests up north in colonies on isolated islands miles from foraging areas. During both breeding season and wintering, this species favors shallow lakes, rivers, and marshes. Unlike the Brown Pelican, the white does not dive, but rather dips its head underwater to scoop up fish. A notable aspect of the American White Pelican is the cooperative foraging in flocks. By swimming in a circle and driving their prey, pelicans can concentrate the fish in the shallows together for easier foraging.