georgia nature

What lives in the bottom of lakes and streams in Cobb County Georgia- benthic organisms!

Benthic organisms are remarkably diverse and vary with habitat. They include protozoa (like amoebas), sponges, cnidarians, flatworms, nematodes, isopods, crayfish, amphipods, mollusks, gastropods, leaches and aquatic worms, pelecypods, insects, and fish. Benthic species I have observed in my area (Cobb County, Georgia) include the Asian Clam (Corbicula fluminea), larval brook salamanders (Eurycea sp.), common sunfishes (Lepomis sp.), the Chattahoochee Crayfish (Cambarus howardi), caddisfly larva (Order Trichoptera), damselflies and dragonflies larval (Order Megaloptera), mayfly larva (Order Ephemeroptera), dragonflies and damselfly larval (Order Odonata), aquatic worms (phylum Annelida), Eastern Dobsonfly larval (Corydalus cornutus), water snakes (Nerodia sp.), longjaw minnow (Ericymba amplamala), river Cooter (Pseudemys concinna), true bugs (Order Hemiptera), true flies larval (Order Diptera), beetles (Order Coleoptera) and stonefly larval (Order Plecoptera). It is worth noting some of these species may only occupy the benthos for a period.

Image of a Brook Salamander. Brook salamanders are a genus, Eurycea, image by Lauren Schramm

Image of a Brook Salamander. Brook salamanders are a genus, Eurycea, image by Lauren Schramm

In some streams, Asian clams, an invasive aquatic species, can be one of the largest components of the benthic invertebrate community (Poff et al.,1993), however this is not the case in all streams in Cobb County. Black et al. (2003) evaluated benthic macroinvertebrate populations of two local streams: Sope Creek and Rottenwood Creek. In Sope Creek they found Ephemeroptera and Diptera to be the dominant orders. In Rottenwood Creek they found Trichoptera and Diptera to be the dominant orders.

An Asian Clam (Corbicula fluminea). Image by Lauren Schramm.

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Water scarcity issues in Georgia/ Cobb County

Georgia experiences several droughts including one from 2005 to 2007 that made headlines as lake levels in Lake Lanier, which serves as a major water reservoir for Atlanta reached record lows. It was shown that this drought cost $2 billion dollars in loses, which included $87.6 million in recreation spending lost from visitors to lake Lanier as the lake levels were down 20.21 feet from full capacity. It was shown that this drought was caused by an increase in consumption rather than anthropogenic climate change. There have been other major droughts in 1954-1956, 1981, 1985- 1988, and 1998 – 2002, 2012 to 2013 and 2017. To lessen the effects of droughts in the future of Georgia, education, voting with our dollars as consumers, and a change in diet are key.

The county that I live in, Cobb County, has an excellent water stewardship program. They have a team of scientist that travel the county and regularly test the quality of streams and rivers. They also provide lots of programming with the public. They are home to the largest adopt-a-stream program in the country which is a great way to engage citizens in water quality issues. They often host workshops where you will make and take home a rain barrel. They also send out quarterly newsletters on water issues in the county and host stream clean ups in partnership with the Department of Natural Resources Rivers Alive program.

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Birds forced to raise kids that are not theirs- Brown-headed Cowbird (Molothrus ater)

The Brown Headed cowbird  (Molothrus ater) is a parasitic bird of North America. They used to follow the bison around and consume the insects associated with them. With the expansion of cattle in North American, the brown-headed cowbird populations have also expanded which has raised some interesting questions. Female cowbirds lay their eggs in the nests of other birds and allow those birds to raise their young. This type of parasitism is called brood parasitism. Because the cowbird is typically larger than these birds their young die in the process of raising the cowbird. Because the cowbird was not tied to a nest this allowed them to follow the bison which was a food rich source. It is unknown if they evolve this strategy to follow bison or were able to follow bison because of this strategy. They also are able to produce more eggs in a season than a typical bird, up to 3 dozen. Bird populations of the birds they parasitize have suffered as a result of this and efforts have been made to try to reduce this. Using feed designed for small birds, not spreading seed on the ground, and avoid feeding sunflower seeds, cracked corn, and millet will reduce the number of cowbirds in your area. It is important to note that the birds are covered by the Migratory Bird Act so it is illegal to remove their eggs from a nest or harm them in any other way without a permit. In some states, if they threaten an endangered species you can obtain a permit to trap the birds.

brown-headed_cowbird

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Coyotes in Georgia- here to stay

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.

coyote_tule_lake_ca

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IDing woody plants in winter- a how to guide

This past Sunday I had the joy of joining a group at a local park in Dunwoody, Georgia for an information session on how to identify woody plants in the winter time. Leaves 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 leaves or not, and items that are surrounding the plant on the ground. Some species of plants are inclined to hold onto their leaves 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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Blog goal

Hello!

My name is Lauren Schramm and ever since I can remember I have learned every bit about the natural world that I could. I graduated from college with a degree in biology and environmental studies. After living in Vermont, New York, and Texas I find myself in Georgia working as an environmental scientist and pursuing a Masters in Wildlife Biology and Fisheries.

DSCN6110.JPGI am trying to learn as much about the natural world as possible. This blog will serve as a place for me to document my learning. My interests are very varied so likely this blog will be as well but it will always be connected to the natural world and educational.