Research Projects

Museum staff are involved with many different research projects of various scope.  All are directed at furthering our understanding of the diversity, range, and function of as well as the threats to native aquatic organisms.  If you have questions about any ongoing studies or would like to share ideas about future research, please contact the collection managers (Brian Helms, Dave Werneke) or any of the collaborators/students listed under each project.

• Alabama Mill Dam Inventory
• Stream crayfish
• Burrowing crayfish  
• Stream design and assessment tools

AL Mill Dam Inventory

(completed 2009)  Collaborators: Michael Gangloff, (PI) Appalachian State University.

Students: Emily Hartfield, DBS graduate student

Small dams are found in nearly every stream in Alabama.  Degraded or poorly constructed dams are a hazard not only to recreational activities but may also threaten survival of sensitive aquatic taxa.  The Alabama Mill Dam Inventory (AMDI) began in 2006 as a cooperative study between Auburn University and the Alabama Department of Conservation and Natural Resources to examine the effect of dams on local physical habitat conditions and biotic assemblages across ecoregions.  We quantified mollusk, crayfish, and fish assemblages and their habitat at 22 small dams, categorized as intact, breached, or relict. Our data revealed that breached dams may have a more substantial negative effect on a wide array of stream biota.  Most surprisingly, we found fewer fishes, mussels and crayfishes in streams with breached dams. Streams with intact or relict mill dams were much more likely to support abundant and diverse aquatic assemblages than were streams with breached dams.  This suggests that removal of more benign dam structures may pose significant risks to streambed stability and sensitive species persistence. When designing restorations in systems supporting at-risk freshwater biota, extensive case-by-case evaluations will be needed to weigh benefits and costs of dam breaching or removal projects.  See the full Final Report to the state here.

Breached dams showing the force of water being expelled,  suspected to have negative effects on certain aquatic biota.

Field crew sampling in the Paint Rock River.                A catch of Pimplebacks (Quadrula pustulosa).

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Stream crayfish: who is where and why?

Collaborators:  Brad Schneid, DBS graduate student; Sue Reithel, DBS graduate student.

These ongoing studies seek to explain the local distributions of stream-dwelling crayfish.  Although many streams have multiple crayfish species present, generally only 1 or 2 species are particularly abundant; however the mechanisms responsible for such distributions are often unclear.  We are using a series of lab-based trials to test inter- and intra-specific shelter competition as an explanation of distribution patterns of 2 abundant crayfish species in Sandy Creek, a tributary of the Tallapoosa River in Chambers Co., AL.  In multiple coastal watersheds of south Alabama (Baldwin Co.), we are using a correlative approach investigate the role of land use and environmental variability in explaining the population sizes of 2 common crayfish species.  Ongoing experiments are investigating the influence of fish predators and variations in life history traits of crayfish species as further factors explaining crayfish distributions.

          Field crew seining for crayfish                                          The Ambiguous crayfish (Cambarus striatus).

            Cambarus striatus                                Procambarus versutus                    Procambarus spiculifer

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Natural history and ecology of burrowing crayfish

Collaborators: Jim Stoeckel, Fisheries and Allied Aquacultures, AU; Chester Figiel, Warm Springs Fish Hatchery,USFWS

Students: Erin Cash, FAA undergraduate student

Nearly all crayfish species are capable of burrowing, and many species spend a considerable portion of their lives in terrestrial burrows.  In fact, some species only leave their burrows occasionally to feed and mate.  Many of these primary burrowing species are habitat specialists with narrowly restricted ranges, thus they are of high conservation concern.  However, due to their cryptic nature, much of the natural history and ecological relationships of burrowing crayfish are poorly known.  With support of the US Fish and Wildlife Service, we are using a combination of field observations and novel lab trials to learn more about the nature of these animals.  Preliminary studies are investigating the mechanics of burrowing and substrate preferences of multiple species, including the Piedmont blue burrower (Cambarus harti). 

                    Novel burrowing chamber used to test crayfish burrowing mechanics and behavior.                            

The Piedmont Blue Burrower (Cambarus harti) in its native habitat.  Photo: USFWS

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Eco-morphological stream design and assessment tools

Collaborators: Eve Brantley, Agronomy and Soils, AU; Greg Jennings, Biosystems Engineering, NC State;  Jim Stoeckel, Fisheries and Allied Aquacultures, AU; Joey Shaw, Agronomy and Soils, AU; Chris Anderson, Forestry and Wildlife Sciences, AU. 

Students:  Tyler Mosley, FAA graduate student

Regional curves are tools used by water resource managers and environmental engineers to predict stream bankfull channel dimensions according to watershed area.  These tools are particularly important as the underlying principles for restoration measures of impaired systems.  With support from the US EPA and in conjunction with researchers at Auburn and NC State, we are developing regional curves for 20 streams in the Alabama Piedmont, a region where curves currently do not exist.  Associated with these efforts is a full ecological assessment of aquatic and riparian conditions to be used as a further tool for future natural stream design.  Museum staff is quantifying the aquatic biota (invertebrates and fish) and their habitat in these streams to serve as biological endpoints where regional curves are to be employed.

Field crew collecting biota and habitat data.

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Crayfish/branchiobdellid symbiosis

Collaborators: Jim Stoeckel, Fisheries, AU; Bryan Brown, Forestry and Natural Resources, Clemson University; Robert Creed, Biology, Appalachian State University.

Students: 

A symbiosis is a close association between 2 species, a relationship that can be considered the outcome of reciprocal exploitation.  Depending on various biotic and abiotic factors, reciprocal exploitation can range from mutualism to commensalism to parasitism to predation.  Cleaning symbioses - a relationships involving a cleaner and a host - appear to lie on such an exploitation continuum.  However, the mechanisms that maintain these relationships as well as the environmental context and community/ecosystem consequences of these relationships are unclear.  With support from NSF, we are collaborating with researchers at Auburn, Clemson, and Appalachian State to determine the mechanisms, context dependency, and broad-scale effects of the symbiosis between native crayfishes (Cambarus chasmodactylus, C. bartonii, and C. striatus) and their respective associated branchiobdellid worms (Annelida), a cleaning ectosymbiont.

Branchiobdellid worms on the carapace and rostrum of the Slackwater crayfish (Cambarus halli).

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