Forest Owlet- an endangered bird

Forest Owlet (Athene blewitti) is an endangered bird that is endemic to Central India. They are small and stocky, just 9 inches tall. For comparison, the barred owl (Strix varia) is 19 inches tall. Forest Owlets eat mostly lizards (60 percent of their diet) but will also eat rodents, birds, invertebrates, and frogs. They mate in between October and May in which they are most easily found as they respond to playback calls. Unlike most other owls they hunt during the day. This is likely because their main prey are lizards which come out during the day to bask in the sun which is when they would be most vulnerable to predation. The owlet is however only a morning person as they are not that active after 10 am. They have a few different calls including a hissing call. Their songs are short and mellow which is unlike other owls.

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The bird was first described in 1873 and then not see after 1884 but then rediscovered in 1997. Before rediscovery knowledge of the bird came from 4 collected specimens from very different areas of India. After its recovery, several populations were discovered and appeared to have significant populations, which causes the bird to go from critically endangered to just endangered. Populations are very fragmented and face pressure from shrinking forest sizes. It requires old growth forest, (according to one source and young forest according to another source) which are some of the forests that are most at risk for logging since they have the largest trees. It needs these forests because they contain tree cavities which it uses to nest in. In 2000 5,000 hectares of Forest Owlet habitat was cleared I order to house people who had been displaced by the creation of a dam. Illegal logging is also a problem as people use the area for agriculture. Overgrazing by cattle removes the ground vegetation which in term reduces the populations of the owl’s prey.

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Scientists think there might be 250 or fewer birds left but there is only solid evidence for there being 25 birds. In 2000 a survey using callback recordings found 25 birds including 3 pairs at Taloda Forest Range and 7 pairs at Toranmal Forest Range. In 2004 another survey found 12 adults and 7 fledglings in Toranmal but no birds in Taloda. In 2009 it was determined that one 2 of the original 7 territories. In 2003 it was discovered that the Satpura Range (Maharashtra) is also home to 9 birds, which is about 300 km away from the other known areas. Thankfully Melghat Tiger Reserve contains over 100 individuals. The owl has always occurred in low density, thus putting it at risk for extinction. In addition males will eat their own chicks. It is protected under Schedule I of the Wildlife (Protection) Act 1972 meaning hunting and trapping of the owl are illegal. It is also Included Appendix I of the Convention on International Trade in Endangered Species (CITES), which means that international trade of the bird is illegal.

 

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Forest Owlet (Athene blewitti) range map

 

Forest eco-systems of Belize

The following has been modified from my field notes from when I took tropical ecology and did a field session in Belize.

In the rainforest ecosystem, the number of symbiotic relationships between organisms is astounding. For example, the relationship between leafcutter ants and the fungus is highly observable in Belize. There is such a great number of these ants that paths are created by them. Leafcutter ant is a generic term for one of 47 species, in the orders  Atta and Acromyrmex. They take leafs from plants and chew them up, this plant material is then fed to a fungus, which they eat. In a sense they are farmers. Since the fungus receives a habitat and the ant receive food, this symbiotic relationship is mutualism. There is a dark side to this relationship though. If a plant is highly desirable by ants they will highly predate on said plant. Because of this, they are seen as pests by farmers, whose crops they can destroy.

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Leafcutter Ants. Captured by Lauren Schramm, Belize City, Belize

We saw a wide variety of epiphytes growing on a wide range of trees. Epiphytes are plants that live on the bark and the branches of other trees. This feature allows the plant to gain access to light with a limited energy investment. Most plant growth is limited by sunlight, water availability, and temperature. They are not parasitic but their weight can damage trees. This is an example of commensal as the trees are not harmed but the epiphyte benefits from the relationship. At the Mayan ruins, we saw one plant that has adapted to solve this issue by shedding its bark, so the epiphytes fall off with the bark. This worked fairly well for the tree but in one area a plant had managed to survive on the tree. The most commonly recognized epiphytes are pitcher plants, “air plants”, and mistletoe (Santalales).

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Class Amphibia

The class Amphibia contains amphibians which are some of my favorite animals. There are three major types which are frogs & toads (order Anura), salamanders (order Caudata), and caecilians (order Apoda). All these orders share certain characteristic including being endothermic, meaning they are unable to regulate their own body temperature. They have both lungs and gills, typically they have gills in the larvae stage but then develop lungs in the adult stage. Their eggs are anamniotic, meaning they are covered by a gelatinous mass that protects the eggs and prevents them from drying out. The warmer and moister an area the more likely it is that they will have more species of Amphibia.

The order Anura contains both frogs and toads, and over 3,400 species! They have longer hind legs than front legs which gives them the ability to hop. The tail is lost in the adult stage and adult males are typically the only ones that vocalize, and they do so to attract mates. Within the order, there are a few distinct families which include the tailed-frog (Ascaphidae),  spadefoot toads (Pelobatidae), narrow-toed toads (Leptodactylidae), true toads (Bufonidae), and true frogs (Ranidae). These are only 5 families. I will post later but this is a good start. If you learned the basic characteristic of each family it will greatly improve the speed and accuracy with which you can identify species.

  • tailed-frog (Ascaphidae)
    • this family only has one species (Ascaphus truei) that lives in the Pacific Northwest
    • ascaphus_truei_web
  • spadefoot toads (Pelobatidae)
    • mostly live underground and come out at night
    • have a horny digger on their hind feet and help them dig
    • breed in temporary pools, and therefore their eggs and larval can develop as quickly as 12 days
    • scaphiopus_couchii_anra
  • narrow-toed toads (Leptodactylidae)
    • most species are tropical and lay eggs on land
    • found in the Southern US to South America
    • there are over 800 species, so characteristics vary widely
    • eleutherodactylus_guttilatus
  • true toads (Bufonidae)
    • over 350 species, 17 species in the US
    • skins very warty with parotid glands behind the eyes
    • shorter legs than frogs as they are designed for hopping, not leaping
    • usually burrow during the day, hunt insects at night
    • a toad light can be set up for their observation See this link by Michigan DNR
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Red-Spotted Toad (Bufo punctatus), captured by Lauren Schramm, Lajitas, Texas
  • true frogs (Ranidae)
    • long legs and slim waist
    • have a very distinct eardrum
    • webbed feet, usually have distinct ridges down the back
    • aquatic larvae, aquatic and terrestrial adults

 

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Green frog (Rana clamitans)  Inlet, NY- captured by Lauren Schramm, photo credit- Peter Spawn

Going back to the salamanders, order Caudata, they are distinct by a long slender body, four limbs, and tail. There are 340 species worldwide. They almost call have smooth skin and glands that promote poison. Salamanders can be found in soil, leaf litter, or in water bodies. They have internal fertilization via spermatophores, which means that the male gives a packet of sperm to the female which she absorbs into her body to fertilize eggs. Breeding occurs in the early spring, often with the 1st warm rain. Salamanders start to migrate to the breeding location, in this process road present a huge barrier to them. Some states even have groups that go out during this time and act as crossing guards for the salamanders. If you are interested I found groups in New Hampshire and Vermont. Sexual dimorphism is common in salamanders meaning that the males and females have different physical characters. The 5 families I will talk about in this blog post are giant salamanders (Cryptobranchidae), mole salamanders (Ambystomatidae), Conger eels (Amphiumidae), lungless salamanders (Plethodontidae), and newts (Salamandridae).

  • giant salamanders (Cryptobranchidae)
    • largest living salamanders
    • fully aquatic
    • the largest species is the giant salamander (Cryptobranchus alleganiensis) which can be almost 6 feet long and lives in Japan
    • one species, the Hellbender (Cryptobranchus alleganiensis), lives in the US but is near threatened
    • 4739185259_6e3f628337_b
  • mole salamanders (Ambystomatidae)
    • characterized by their stout bodies
    • found in the US and Canada
    • there are 30 species of this burrowing salamander
    • named after the fact that they only emerge to breed

    eastern_tiger_salamander_28ambystoma_tigrinum29_282552238976229

  • Conger eels (Amphiumidae)
    • only 3 species
    • named the overall body shape
    • found in the southern US
    • named for the number of toes they have; One-toed amphiuma (Amphiuma pholeter), Two-toed amphiuma (Amphiuma means), Three-toed amphiuma (Amphiuma tridactylum)
  • 4625374379_f74148c602_b
  • lungless salamanders (Plethodontidae)
    • breathe through the skin and the mouth
    • there are over 250 species, making it the most diverse family of salamanders
    • most are found in the Americas but a few are found in Europe
    • 20180111_195853.jpg
      Red-backed salamander (Plethodon cinereus)- captured by Lauren Schramm, Norcross, GA
  • newts and salamanders (Salamandridae)
    • has the largest geographic distribution of any salamander family
    • has two subgroups that contain true salamanders (genera ChioglossaMertensiella, and Salamandra) and newts (other genera)
    • most adults are smaller and rarely longer than 20 cm
    • notophthalmus_viridescenspcca20040816-3983a

Finally, the last order, Apoda, contains caecilians, which are the lesser known group of amphibians and for good reasons. Caecilians is latin for blind onesThey are basically salamanders without legs, although some do have very tiny legs. They live underground and very little is known about them. There are 160 species. THeir eyes may be covered with bone or skin. They hunt prey underground using their head as a sensor. My old biology professor called them nightmare material. vivipary is common among them, meaning that the young develop inside the mother and then they are born. They are found in the tropics in of South and Central America, Africa, and southern Asia. Their skin contains calcite scales which led scientists to originally think they were related to Stegocephalia which is a salamander/ lizard-like creature that lived 350 million years ago.

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Stone Mountain- natural wonder of Georgia

Stone Mountain is metro Atlanta’s most popular hiking spots. It also happens to be one of the 7 natural wonders of Georgia joining the ranks of; Amicalola Falls, Warm Springs, Okefenokee Swamp, Providence Canyon, Radium Springs and Tallulah Gorge. Stone Mountain is a giant igneous monolith that has a circumference of 5 miles at the base above ground but extends further underground. While it is very large it is not the largest piece of granite in the world, and some of the mountains is not composed entirely of granite, composition ranges from quartz monzonite to granite and granodiorite according to the Georgia Geological Survey Bullet. It is unclear what the largest piece of granite in the world is; I’ve heard the same claim from the Polar Caves in New Hampshire and from a rock in Yellowstone. It was formed from an upwelling of magma, about the same time that the Blue Ridge Mountains were formed.

There are many interesting species to observe at Stone Mountain as well. During the rainy season in the pools clam shrimp (Laevicaudata) and fairy shrimp (Anostraca) can be observed. Both of these are orders of small bivalves and crustaceans. The fairy shrimp is most commonly known as the sea monkey. Clam shrimps are very similar but they have a protective shell around the shrimp. They are both able to enter a state called diapause, in this state the eggs basically dry out and remain that way until it rains again. The eggs can even survive being out in space! Centuries later the eggs are still able to hatch. The species are not mobile unless they are aided by wind, bird’s feet, or currents. Fairy shrimp can well found on every single continent, including Antarctica.

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Spotted Salamander (Ambystoma maculatum)

For the 1st species Sunday I am writing about the Spotted Salamander (Ambystoma maculatum).

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In high school, I actually raised some from eggs. I learned a lot about them and salamanders in general during that process and they are very interesting animals! They are found all over the Eastern U.S. and are considered to have stable populations. Adults live in a forest and they lay their eggs in vernal pools or water bodies that lack fish. A vernal pool is an area that only has water during the spring, usually due to melting snow, and they serve as important habitat for amphibians. Adults are between 6 and 10 inches long but are rarely seen because they live in leaf litter, under logs, or in tunnels. They are also active at night.

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Coyotes in Georgia

Today I attended a lecture by Dr. Christopher Mowry who teaches at Berry College and founded the Atlanta Coyote project. The presentation opened with an image of a coyote (Canis latrans) standing inside Piedmont Park, which was taken in 2016. Coyotes belong to the Genus Canis, which is also home to the gray wolf (Canis lupus), red wolf (Canis rufus), and domestic dog (Canis lupus familiaris). While the gray wolf and coyote are agreed to be clearly separate species by experts, the red wolf has a lot of coyote genes. Both the red wolf and coyote are endemic to North America, meaning they are native and only found in that region. Sadly, the red wolf is now only found in the wild inside Alligator River National Wildlife Refuge in North Carolina.

Historically coyotes were a great plains species. They moved westward for two reasons in particular. The gray wolf is a natural predator of the gray wolf as is the red wolf. Due to the elimination of these predators the coyote was able to expand into new territory. But historically there was a region in which the gray wolf and coyote did live together, known as an admixture zone, where possible hybridization occurred. Urbanization also created an ideal habitat for the coyote, as it creates more edge habitat which increases their food supply of small mammals. For these regions, the coyote can now be found in every state, except for Hawaii.

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IDing woody plants in winter

This past Sunday I had the joy of joining a group at a local park in Dunwoody, GA for an information session on how to identify woody plants in the winter time. Leafs typically are the easiest way to determine what plant you are observing but in the winter you have to rely on other clues. Clues you can use include leaf arrangement, overall plant shape, the bark if the plant has leafs or not, and items that are surrounding the plant on the ground. Some species of plants are inclined to hold onto their leafs while others will not. It is theorized that plants act like this to discourage deer grazing.

Before we dive into the different plants it is important to get some definitions straight. As with most of science, the general public tends to use terms that have very specific meanings and this can lead to confusions. It is also important to make sure that you are using live twigs to identify plants. Dead twigs will snap and can contain missing parts that will lead to misidentification.

  • A twig: the plant’s past year growth, general different in appearance on the plant
  • opposite leaf arrangement: the plant has twigs that are directly across from each other
    • there are fewer of these than alternate, so it’s a great clue when IDing plants
    • all Ashs, Maples, and Buckeyes have opposite leaf arrangement
  • alternate leaf arrangement: the plant has twigs that are staggered
  • lenticels: tiny dots or slops in the barks, helps the plant to bring more oxygen
  • leaf scar: the pattern that is made when the leaf falls off
    • helpful to have a macro lense to observe this

It is also important to note that plants have both flower and leaf buds. They are different and will look different from each other including the twigs which they are on. If the bark is shiny it generally means that it has a lack of hairs. Now time to divide into the different plants we observed, and how to determine that they are that plant.

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