What kinds of crayfish might you expect to find in the Ogeechee?

What kinds of crayfish might you expect to find in the Ogeechee?  With so much aquatic diversity in the basin, what you might see in the upper part of the basin can be completely different from what you might see near the coast. That’s because, even though the river is well connected from top to bottom, the habitats found in the upper part of the basin are completely different from the coastal habitats.

The headwaters of the Ogeechee form on the far extent of the Piedmont (the geographic region separating the coastal plain from the Appalachian mountains) making for clearer and swifter flowing water. But as the Ogeechee slowly snakes its way towards the coast, the water starts to move slower and slower, becoming much darker due to the leaching of tannins. Understandably, these stark differences result in differing crayfish fauna.

Procambarus pygmaeus

In the upper part of the basin, the Variable crayfish (Cambarus latimanus) and the Brushnose crayfish (Procambarus pubsecens) are two commonly found species that are strongly associated with this part of the basin, and are rarely if ever found downstream of Millen, Georgia. The Variable crayfish is one of only a couple of species within the genus Cambarus found within the Ogeechee basin, with the vast majority of other species belonging to the genus Procambarus. This is because, in general, Cambarus species are strongly associated with more rocky streams, like those found in the Piedmont. The Brushnose Crayfish is very similar to other Procambarus species found throughout the basin, with the namesake difference being dense hairs along the rostrum (nose area) of the crayfish.

Cambarus latimanus

Some species that can be found in both the upper and lower sections of the basin are the Ogeechee crayfish (Procambarus petersi), Blackwater crayfish (Procambarus litosternum) and Red Swamp crayfish (Procambarus troglodytes). The Ogeechee crayfish, though not common, can be found from the headwaters almost to Savannah. The Blackwater crayfish is incredibly common, and can be found in small streams all over. Chances are, if you’ve seen a small crayfish poking around in a stream in the basin, it was a Blackwater crayfish. The Red Swamp crayfish is one most people are familiar with – it is what people commonly catch for food, and they are easily distinguishable by their large, tubercle-covered red claws.

Procambarus troglodytes

Lastly, you might see as the Ogeechee is flowing into the ocean would be the Hummock crayfish (Procambarus lunzi), and the Christmas Tree crayfish (Procambarus pygmaeus). Both of these species are more associated with slower, stagnant water; but the Christmas Tree crayfish has one particularly interesting adaptation. The bright colors of the Christmas Tree crayfish are thought to be used as camouflage, as it is almost always found in dense mats of lush aquatic vegetation. 

Hopefully this brief introduction to some of the crayfish found within our basin encourages you to get out and explore some of the novelties that make this basin a special place!

(All photos courtesy of Chris Lukhaup and Chris Skelton)

Earth Month

We are calling on YOU to celebrate Earth Day with us the entire month of April! Come up with creative, fun and effective ways to better your environment and celebrate the Earth.

Here are some of the ways we are celebrating Earth Day :

  • Friday, April 8, you can find ORK at the Russell Union on GS Statesboro Campus as a part of Southern Sustainability week 
  • Saturday, April 16, ORK will be assisting with a private volunteer cleanup on the Vernon River with Asbury Memorial Church
  • Saturday, April 23, join our Earth Day community cleanup in the upper watershed
  • Monday, April 25, come join our public Don’t Litter Lotts Cleanup, in Statesboro
  • Saturday, April 30,  you can find us at Fire Festival at the Mary Kahrs Warnell Forest Education Center in Guyton
  • Saturday, April 30, we’ll be on the Canoochee River during our first members-only event of the year, alongside guides from Ft. Stewart, we’ll explore the Canoochee from kayaks and canoes.

If you visit us at any of these events, or celebrate Earth Month in some other way, send your photos to info@ogeecheeriverkeeper.org or tag us on social media by April 30.

Why should we care about freshwater organisms?

Why should we care about freshwater organisms? This is an incredibly common question directed towards freshwater ecologists like myself, and it’s completely valid. Why spend all the time and effort to study things that appear to have little to no impact on human welfare? While the ultimate answer to this question is nuanced, one of the most important reasons why we as scientists care about them is their use as bioindicators.

The concept of a bioindicator is fairly straightforward, generally referring to the use of a living thing (bio-) as an indicator for the health of the ecosystem it lives in. For example, let’s say that there’s a rare crayfish species that is known to only occur in pristine habitat with very clean water, and has no tolerance for pollution of any kind. Therefore, if that species is found, scientists can use it as evidence that the stream it was found in is very healthy. On the flip side, if the only species that are found in a specific stream are fairly common and can tolerate a large range of conditions, then these species might indicate that that stream has poor water quality.

Female Red Swamp Crayfish from 15 Mile Creek, with young on the abdomen. Image by Ray Chandler.

Beyond being good “tools” for humans to assess the health of our ecosystems, different freshwater organisms serve distinct purposes in the aquatic food web. This is especially true of crayfishes, which are commonly viewed as “keystone” species. A keystone species is one that performs such an important role in an ecosystem that without it, there would be a large-scale detrimental effect on the rest of the ecosystem.

The crayfish is a keystone species for a variety of reasons. Firstly, crayfish are omnivorous, eating all kinds of different things in stream ecosystems, from other smaller insects to plant matter. Secondly, crayfish are important food sources for larger predators, like sport fish and amphibians. This combination of  eating and being eaten by so many different things make crayfish an integral part of aquatic food webs. 

Thirdly, crayfish act as “ecosystem engineers” through the creation of burrows. Many of you may be familiar with crayfish burrows that you see on land (check out this article), but what many people don’t realize is that all crayfish burrow to some extent. In stream ecosystems, these underwater burrows act as key habitat for other freshwater organisms, and therefore harbor the diversity of life that is important for healthy streams.

A crayfish burrow found in the field in southern Georgia.

With spring already in full swing, I’m sure many of you will be seeing crayfish a lot more often, and I’m excited to write more about what you may see out in the watershed.

Define a watershed

Come up with your own definition of watershed using clear and descriptive words. The best definition of watershed will win some ORK swag!

The most commonly used definition is: “A watershed is a system of how water flows through an area moving sediment, water and dissolved materials into a common point.”

This concept can be confusing and many of us forget its meaning over time. We’re calling on *YOU* to come up with a creative and easy way to remember what a watershed is!

Submit your definition of a watershed to info@ogeecheeriverkeeper.org or tag us on social media.

Thanks to Connie at Savannah-Ogeechee Canal for the activity idea!

Additional Activity:

The Ogeechee Watershed (see map) has many types of ecosystems within it including freshwater from the Piedmont region, to blackwater rivers and swamps in the Coastal Plain region and runs all the way to the Georgia coast. Include ecological information about your watershed including but not limited to animals, soil types, plant life, human impacts and more.


Activity is open to all ages and meets the needs or can be combined with other activities for the Georgia Standards of Excellence in Science.

 

  • S3L1. Obtain, evaluate, and communicate information about the similarities and differences between plants, animals, and habitats found within geographic regions (Blue Ridge Mountains, Piedmont, Coastal Plains, Valley and Ridge, and Appalachian Plateau) of Georgia.
  • S3L2. Obtain, evaluate, and communicate information about the effects of pollution (air, land, and water) and humans on the environment.
  • S4E3. Obtain, evaluate, and communicate information to demonstrate the water cycle.
  • S6E3. Obtain, evaluate, and communicate information to recognize the significant role of water in Earth processes.

 

 

PRESS RELEASE: ORK, City of Savannah install litter traps to Protect the Vernon

OGEECHEE RIVERKEEPER, CITY OF SAVANNAH INSTALL LITTER TRAPS TO PROTECT THE VERNON
Effort is part of a long-term project to improve the health of the Vernon watershed 

Ogeechee Riverkeeper (ORK) and the City of Savannah are partnering to lead a long term project to protect the water quality and ecology of the Vernon River. Two litter booms were recently deployed in an effort to catch litter before it reaches the river or the ocean. The booms were installed in the Chippewa and Harmon Canals. These traps will be cleaned out regularly and the litter will be sorted, analyzed, cataloged and then recycled or disposed of responsibly. 

The booms were designed and installed by Osprey Initiative, and were paid for by a grant from the National Fish and Wildlife Foundation (NFWF). ORK received the 5 Star grant from NFWF for its comprehensive plan involving multiple stakeholders in the area. 

In 2021, ORK the City of Savannah, and other stakeholders set out to restore the waterways in the Vernon River basin to the point that it can be delisted as an impaired waterbody by GA EPD; and to reduce the amount of litter and plastic pollution entering the waterways. The canals and tributaries that feed the Vernon River are highly impacted by urban development.

“All of Savannah’s stormwater infrastructure flows into a public waterway,” says Laura Walker, Water Resources Environmental Manager for the City of Savannah. “These waterways are lifelines to Savannah’s environmental and economic health. We work hard every day to try and keep them fishable and swimmable. But we need everyone to treat the storm system with care. We need everyone to protect the storm drains, ditches, and creeks and keep them clean.” 

The Vernon River receives a significant amount of the stormwater leaving the City of Savannah, via Wilshire Canal, Harmon Canal, Casey Canal, and Hayners Creek, all part of the Ogeechee River watershed. The goal is to improve water quality, restore ecological habitat, and “Protect The Vernon” from current and future threats. 

“We are so grateful for the broad group of stakeholders working with us to minimize the threats that urban runoff, and litter and plastic pollution pose to this special waterbody,” says Damon Mullis, riverkeeper and executive director. “Local residents are encouraged to volunteer for litter cleanups, citizen science programs, educational events, and more in the coming months.”

Sign up to volunteer, view data, watch an installation video, and view the successes to date: https://www.ogeecheeriverkeeper.org/vernon

About Ogeechee Riverkeeper: Ogeechee Riverkeeper 501(c)(3) works to protect, preserve, and improve the water quality of the Ogeechee River basin, which includes all of the streams flowing out to Ossabaw Sound and St. Catherine’s Sound. The Canoochee River is about 108 miles long and the Ogeechee River itself is approximately 245 miles long. The Ogeechee River system drains more than 5,500 square miles across 22 counties in Georgia. More at ogeecheeriverkeeper.org.

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