# Presentation: 591919

## Assessment of the Potential for Zebra Mussel 

** **
**Assessment of the Potential for Zebra Mussel **
**Invasion of Waters in the Western United States **
**via Saltatory  Dispersal and Evolution**
** ****of Increased Thermal Tolerance**
**Dr. Robert F. McMahon**
**Professor of Biology and Dean of the Honors College**
**John A. Morse**
**Graduate Research Assistant **
**The University of Texas at Arlington**
**Box 19222**
**Arlington, Texas  76019**
**11 September 2007**

**UT Arlington**

## Research Objectives

**Compare the acute and chronic upper thermal limits of zebra mussel populations from a warm southwestern habitat and cooler northeastern habitat**
**Use data to assess development of physiologically resistant (thermally tolerant) races of zebra mussels in isolated southwestern populations**
**Comparing genetic fingerprints (Amplified Fragment Length Polymorphisms or AFLP)** **of isolated zebra mussel populations and comparing them with samples from potential source populations**
**Use data to examine how mussel dispersal patterns from one drainage system to another**

## Results

**Results**
**Chronic Thermal Tolerance**
**Mussel samples collected from Lake Oologah, Oklahoma (2206, 2007), and Saratoga Lake (2006) and Hedges Lake (2007)  in New York**** **
**Acclimated in the laboratory for over two weeks to 5°, 10°, 15°, 20°, 25° and 30°C**** **
**Subsamples held concurrently for up to 28 days at temperatures of 28°C, 29°, 30°, 31°, 32°, 33° and 34°C**
**Samples checked daily for mortality **
**Dead individuals removed**

## Mortality after 28 days at 29°C in zebra mussels acclimated to 25° and 30°C (2006) 

**0**

**10**

**20**

**30**

**40**

**50**

**60**

**70**

**80**

**90**

**100**

**25**

**°C**

**30**

**°C**

**Acclimation Temperature**

**% Mortality**

**Mortality after 28 days at 29°C in zebra mussels acclimated to 25° and 30°C (2006)**

## 28-Day Chronic Thermal Test Results 2007 

**Numbers above bars represents the time (in days) to achieve 100% mortality**

**14**

**16**

**6.5**

**26**

**4.5**

**19**

**3**

**5.5**

**2**

**1**

**1.5**

**0.5**

**0.5**

**0%**

**10%**

**20%**

**30%**

**40%**

**50%**

**60%**

**70%**

**80%**

**90%**

**100%**

**27°C**

**28°C**

**29°C**

**30°C**

**31°C**

**32°C**

**33°C**

**34°C**

**Test Temp**

**% Mortality**

## Oologah Lake Water Temperature

**0**

**5**

**10**

**15**

**20**

**25**

**30**

**35**

**Jul**

**Aug**

**Sep**

**Oct**

**Nov**

**Dec**

**Jan**

**Feb**

**Mar**

**Apr**

**May**

**Jun**

**Month**

**Oologah Lake Water Temperature**

**2006**

**2007**

## Mortality after 28 days at 29°C in Lake Oologah zebra mussels acclimated to 20°, 25° and 30°C in 2006 and 2007 

**Mortality after 28 days at 29°C in Lake Oologah zebra mussels acclimated to 20°, 25° and 30°C in 2006 and 2007**

## Lake Mead Quagga Mussel Research

**Lake Mead Quagga Mussel Research**

## Size Distributions of Quagga Mussels in Lake Mead 

**Size Distributions of Quagga Mussels in Lake Mead **

## 28 Day Mortality for Lake Mead Quagga Mussels Exposed to 20°C – 33°C

**Numbers above bars represent the approximate number **
**of days to reach 100% mortality.**

**0%**

**10%**

**20%**

**30%**

**40%**

**50%**

**60%**

**70%**

**80%**

**90%**

**100%**

**% Mortality**

**20d**

**5d**

**2d**

**1/2d**

**1/4d**

**20°C**

**21°C**

**22°C**

**23°C**

**24°C**

**25°C**

**26°C**

**27°C**

**28°C**

**29°C**

**30°C**

**31°C**

**32°C**

**33°C**

**Temperature (°C)**

## Lake Mead Temperature Profile at Sentinel Island

**Lake Mead Temperature Profile at Sentinel Island**

## Isolated Water Bodies Sampled

| ISOLATED WATERS |  |  |
| --- | --- | --- |
| Water Body | State | Comments |
| Oologah Lake (after Aug. 2006) | OK | Obtained |
| Oologah Lake (before Aug. 2006) | OK | Obtained |
| El Dorado | KS | Obtained |
| White River | AK | Collection planned |
| Ossawinnamakee Lake | MN | Possible collection |
| Saratoga Lake | NY | Obtained |
| Hedges Lake | NY | Obtained |
| Ballston Lake | NY | Obtained |
| Base Lake | NE | Collection planned |
| Lake of the Ozarks | MO | Obtained |
| Diamond Lake | MI | Obtained |
| Detroit River | MI | Obtained |
| Wolf Lake | IL | Obtained |
| Mosquito Creek Reservoir | OH | Obtained |
| Milbrook Quarry | VA | Obtained |
| Lake Mead* | NV | Obtained |

| NON-ISOLATED WATERS |  |  |
| --- | --- | --- |
| Water Body | State | Comments |
| Mohawk River | NY | Obtained |
| Lake Michigan**  | MI | Obtained |
| Lake Erie** | OH | Obtained |
| Lake Ontario* | NY | Obtained |
| St. Lawrence River* | NY | Collection planned |
| Upper Mississippi |  | Collection planned |
| Lower Mississippi | LA | Collection planned |

## Preliminary Conclusions

**Zebra mussels from Lake Oologah, Oklahoma are not more thermally tolerant than those from Saratoga or Hedges Lake in New York **
**No evidence for selection of elevated thermal limits**
**The incipient (long-term) upper thermal limit of zebra mussels Lake Mead qugga mussels appears to be ****≈**** 28°C regardless of latitude in North America**
**The Lake Oologah, Oklahoma, zebra mussel population experienced near 100% extirpation during August 2006 and 2007 when water temperature rose above 28°C**
**No evidence of selection for elevated thermal limits **
**Lakes exceeding a surface temperature of 28°C for extended periods in the summer are unlikely to harbor zebra or quagga mussels**
**Quagga mussels were first introduced to Lake Mead in 2003 or 2004**
**Temperature profiles can be use to estimate the susceptibility of southwestern water bodies to zebra mussel invasion**
**Lake Mead and the Lower Colorado River Lakes are susceptible to quagga and zebra mussel invasion**
**Molecular analysis of the origins of isolated zebra mussel introductions will be completed by December 2006**