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Ecology and Management of Stream Corridors |
A
typical southeastern stream corridor is a wetland complex composed of
flowing-water aquatic habitats, adjacent riparian habitats, and periodically
flooded bottomland habitats. Also, any particular stream corridor is just a
segment of a drainage system with a sequence of corridor zones associated with
streams from headwaters to large rivers. Stream corridors are important sources
of renewable resources such as commercial and recreational fisheries,
aquatic-oriented wildlife, and terrestrial wildlife utilizing productive
bottomland areas. In addition, stream corridors are highly valued recreation
and aesthetic areas due to high biological productivity and landscape
diversity.
Stream
corridors have always been, and continue to be, the focus of many forms of
economic and land developments that exert some effect on these systems. Impacts
to stream and river systems basically stem from two general factors, altered
hydrologic conditions (i.e., water quality and quantity) and physical
alterations of streams and associated lands (e.g., agricultural plots,
backwater draining, navigation improvements). Both land and water changes tend
to influence the integrity of instream, riparian, and
bottomland communities since all these habitats are dependent on water/land
relationships. The natural flowing-water processes of erosion and deposition
impose a dynamic character to instream, riparian, and
bottomland habitats and their associated fish and wildlife communities. Human
modifications to stream corridors tend to intensify this dynamic character and
frequently require continual human intervention to maintain artificial stream
corridor conditions.
The
most pressing areas of research involving stream corridors concern the
interactions between fish and wildlife communities and the physical and
chemical processes of flowing waters. The Unit intends to develop research that
integrates fish and wildlife resource characteristics and functions with the
hydrologic processes that influence stream corridor habitats. Specific areas
for development include: renewable resource management, conservation of
species, preservation of communities, impact assessment and prediction of
effects, and mitigation and restoration.
Effects of surface mine reclamation on aquatic communities (completed)
Improved
detection of largemouth bass virus in infected fish (completed)
Funding Source (s): Alabama Division of wildlife and Freshwater Fisheries
Principal Investigator (s): Elise Irwin
Research Associate (s): Jeff Jolley
Student (s): Peter Sakaris (PhD)
Duration: October 2000 – September 2003
Striped bass and catfishes were collected by boat electrofishing from 6 March 2002 to 15 November 2002 and
from 6 March 2003 to 10 July 2003 for a total of 42 sampling days in the lower
Tallapoosa River near Tallassee and Ft. Toulouse, AL. Prepositioned
Area Electrofishers (PAEs)
were also used to assess catfish and bass recruitment at three tributary sites
(Uphapee, Line and Cubahatchee
creeks) and two sites in the main stem of the lower Tallapoosa River. Fish were
weighed, measured and aged using otoliths. We
determined that age of fish and mean fall discharge explained 92% of the
variation in growth of striped bass (r2=0.92, P<0.01). Negative linear
relations were found between year-1 striped bass growth and mean discharge, indicating
that young fish were probably more sensitive to increased discharge than
adults. Age accounted for 74% of the variation in growth of flathead catfish
(r2=0.74, P<0.01); the addition of hydrologic variables did not improve the
overall model. However, a transition from positive linear relations with
discharge at young ages to strong, negative linear relations in older ages was
evident. For channel catfish, age explained 84% of the variation in growth
(r2=0.84, P<0.01), and the addition of hydrologic variables did not improve
the overall model. However, channel catfish also exhibited a transition from
positive linear relations with discharge early in life to strong, negative
linear relations later in life. Age and mean fall flow accounted for 78% of the
variation in growth of blue catfish (r2=0.78, P<0.01). Blue catfish appeared
to respond negatively to increasing discharge throughout their lives.
Relationships between recruitment and discharge could not be quantified for
striped bass and catfishes, but it appeared that strong year classes of
flathead catfish formed in years with low spring and winter discharges. Prepositioned Area Electrofisher
sampling indicated juvenile channel catfish and flathead catfish were using
tributaries of the lower
Funding
Source (s):
Principal Investigator (s): Elise Irwin
Research Assistant (s): Kevin Kleiner
Student (s): Jeff Jolley (MS)
Duration: September 2000 – September 2003
Recently,
recreational anglers have petitioned the Alabama Division of Wildlife and
Freshwater Fisheries (ADWFF) to close commercial harvest on several
reallocated
to recreational harvest after the commercial fishing ban. Careful evaluation of
multiple-use fisheries is needed prior to implementation of drastic measures,
such as closure of fisheries. Although methods exist to measure population
parameters (i.e.; abundance, age and growth, recruitment) of wild catfish
stocks, assessment of
been
implemented. The objectives of this project are to assess the size and
age-class structure, movement, and recreational and commercial harvest rates of
channel catfish, blue catfish and flathead catfish at impounded and tailwater sites on the
Status – A total of 1,549 catfishes from 6 sites were collected, with 302 collected at the Mitchell tailrace, the most productive site. We had only 6 tag returns, but routinely collected tagged fish in our sampling efforts. Tag loss for flathead catfish was 34%; this rate was higher than other published accounts. Based on mark-recapture, movement of flathead catfish was minimal, though new insights into estimates of movement based on tagging studies cause concern for making assumptions. Reported angler harvest rates were low (blue catfish, 4%; 0.50, flathead catfish); however, non-reporting rates and tag loss rates were likely high. Participating anglers were difficult to recruit and no commercial operations were observed during the course of the study. In addition to project objectives, a fish health assessment and condition analysis was completed. The final report has been prepared and results indicate that tailwater areas support more abundant, larger catfishes, in higher condition than reservoir areas. In addition, inundated shoal habitat and deep water habitats were preferred by large flathead catfish and blue catfish. In tailwater areas blue catfish and channel catfish were larger and had higher growth rates, channel catfish were in better condition, and flathead catfish were more abundant and had a population structure that included a wide size range. Increased growth, abundance and condition appear related to physical habitat and/or diet diversity and quality. Whereas, fish prey was important for all three species in tailwater areas, and more prey types were consumed in tailwaters versus reservoir areas. The health assessment required few samples, minimal training, and provided a “snapshot” of the gross condition of the populations. A final report was submitted, one manuscript is in press and three additional papers are in preparation.
Redeye
bass population status and critical habitat delineation in the
Funding
Source:
Principal
Investigator: Elise Irwin
Research
Associate: Jeff Jolley
Research
Assistant: Daniel Neil, Allen Nicholls, Brad Hopkins
Student: John R.
Knight, Taconya Piper
Duration:
October 2002 – September 2004
Redeye bass (Micropterus coosae)
provide an abundant, yet rarely utilized fishery resource in piedmont streams
of
Status –Ninety-five redeye bass were aged with
spines and otoliths.
Sagittal otoliths
and spines (second and third dorsal) were extracted for aging. Fish up to age 7 were collected based on otoliths. Spines
tended to underage fish, the oldest fish was age 5. Ages estimated with the two structures were
within one year 94.7% of the time and were the same 66.3% of the time. Spines may be a viable option for non-lethal
ageing. A radio telemetry study to
assess habitat use and movement is in progress in Hillabee
Creek. Radio tag retention by redeye
bass was 100% (tags were retained 30 days with no infection). Ten fish were collected, and subsequently
tagged, in August 2003 within a large bedrock shoal on Hillabee
Creek. Fish were located 3-4 times weekly
and exhibited variable movement patterns.
Six fish appeared to be resident in nature and four fish moved
considerable distances downstream, and either returned (2 fish) or remained
downstream (2 fish). All Fish were
associated with instream and canopy cover. Fish were generally associated with large
substrata (e.g., from cobble to bedrock).
In summer 2004, 10 redeye bass were tagged in the main stem of the
Funding Source (s): Alabama Department of Environmental Management
Principal
Investigator (s): Elise Irwin, Wesley Wood (
Research Associate (s): Katie Mickett
Student
(s): Deirdre Black (MS)
Duration: February 2000 – December 2002
Extensive areas of abandoned mine lands and acid mine
drainage (AMD) severely impact water quality in the
Status – Possible stream sites were marked
at road crossings on 7.5-minute USGS topographic maps in the Warrior coalfield;
15 and 36 sites (18 known AMD streams and 33 streams of unknown impact) were
sampled in 2000 and 2001, respectively.
Invertebrates were sampled and identified to family. In-situ
water quality parameters included: conductivity, pH, temperature, DO, depth, flow, and stream width. Categorical analysis was used to build
classification trees to categorize streams based on level of impact (AMD,
neutral or mixing zone). The model
correctly predicted a class of “AMD” every time. Of 10 quantitative and one qualitative
parameter (s), alkalinity, pH, hardness, and Al concentration explained over
90% of the variation among categories.
The invertebrate model also classified all of the known AMD sites as “AMD.” The water quality model classified 67% of the
known acid impacted sites as “AMD” and 33% as “neutral.” The models were in agreement as to the stream
classification 54% of the time. Results
suggest that the invertebrate model is more robust for detection of AMD
impacts; however, the two models used together will increase ability to
classify other less impacted sites. Of
significance was the finding that 30% of sites (unknown) were classed as “AMD.”
Funding Source (s): Alabama Department of Industrial Relations
Principal Investigator(s): Elise Irwin
Research Associate(s): Katie Mickett
Research Assistant(s): Wendi Benson
Student(s): Deidre Black (MS)
Duration: February 1997 – March 2003
Expenditures for fishing in rivers and streams in
Status – Aquatic
macroinvertebrates were collected monthly June
1996-May 2002 to encompass the pre, during and post--reclamation periods. However, the site has not been fully
reclaimed and pH has not responded. Fish
were also collected in the first phase of the study; the fish community is not
diverse, even at unimpacted sites; differences in
species richness have been documented among sites. We used the water quality and invertebrate
data as training data to develop a biological and chemical rapid assessment
technique for a concurrent project (see above).
Invertebrate communities vary among sites with different pH and metal
and ion concentrations. The acid mine
drainage stream and associated mixing zone were characterized by low species
richness. Species richness was higher in
the pH neutral stream and downstream of the mixing zone. Water quality and biological recovery goals
have not been met.
Funding
Source(s):
Principal
Investigator(s): John Grizzle (
Student(s): Ilhan Altinok (Postdoctoral Fellow), Benjamin Beck (MS)
Research Associate(s): Andrew Noyes
Duration: September 2001 – September 2003
Largemouth bass (Micropterus salmoides) is a premier sport fish in
Status – This project has been completed. A polymerase chain reaction (PCR) was designed and evaluated for detection of largemouth bass virus (LMBV). This method was published in Diseases of Aquatic Organisms and has been adopted by several laboratories working with LMBV. This new method will be included in the next version of Standard Procedures for Aquatic Animal Health Inspections, jointly published by the U.S. Fish and Wildlife Service and American Fisheries Society–Fish Health Section.
Funding
Source:
Principal
Investigator: Elise Irwin
Research
Associate: Kathryn Mickett
Duration: October 2004 – September 2006
The
Status
- The final report for this project is complete. In 2005, we sampled 20 sites to collect
baseline data from seven proposed or operational combined-cycle plants
(formerly referred to as “co-generation” plants). In 2006, we concentrated sampling effort at
six sites around three combined-cycle plants with active permits. A total of 72 fish species were collected and
identified; occupancy rates (range: 0 to 1) and detection probabilities (range:
0 to 0.87) varied by sampling location and by species. Temperature was monitored and water samples
collected at the discharge for two plants operated by Tenaska
Energy in
Funding
Source:
Principal
Investigator: Elise Irwin
Research
Associate: Kathryn Kennedy
Duration: August 2007 – December 2008
Wheeler
National Wildlife Refuge (WNWR) located in North Alabama adjacent to Wheeler
Reservoir on the Tennessee River encompasses 35,000 acres, and includes several
satellite Refuges. During recent Biological Review of WNWR,
recommendations were made to complete an assessment of occupancy rates and
overall fish health in relation to water quality for nongamefishes on refuge lands. In addition to Wheeler
Reservoir, streams that drain to the reservoir are located on refuge lands and
current information is lacking regarding fish populations in these
systems. Refuge personnel are also concerned about overall health of the
aquatic systems on the Refuge and are interested in the incidence of disease or
other abnormalities expressed by fishes inhabiting aquatic systems on the
Refuge. It is hypothesized that water quality is compromised in several
water bodies on the Refuge, therefore warranting a quantitative assessment of
how water quality parameters
may be affecting both fish occupancy rates and overall fish health.
The
objective of this project is to estimate occupancy rates and health for fish
species inhabiting Wheeler Reservoir and streams located on refuge lands. Specifically, we will 1) provide Refuge staff
with probability of occurrence for each species in water bodies on the Refuge
2) conduct a fish health assessment for fishes encountered during the survey,
3) measure water quality parameters and other covariates that may affect
occupancy and fish health at each site, and 4) investigate relations between
physical and chemical characters of the streams and reservoir and fish
population characters.
Status
- We will begin sample collection of stream
and reservoir fishes in spring 2008. A
list of potential fishes will be developed from historic databases and expert
opinion. Potential survey sites will be
selected in a systematic random fashion and visited during a short temporal
period (5-7 days) for collection of fish species. Water and sediment samples will be collected
and analyzed; resulting parameters and other water characteristics collected in situ (e.g., temperature,
conductivity) will be used as covariates for occupancy estimation and model
selection. A modified fish health
assessment index (HAI) will be calculated for a subsample
of individuals of each fish species from each site. This health assessment considers gross
abnormalities, parasites, and condition of internal organs. The health index values will be analyzed
relative to water and sediment chemistry and other variables using categorical
regression trees.