analyze the number of samples required with the commonly used small core sampler, to 

 meet statistical requirements it could also preclude their use in streams with low 

 salmonid runs. 



This method also has disadvantages that other methods do not. It requires the 

 stoppage of most of the surface flows. However, this should probably be done in all 

 freeze core sampling to prevent the bulbous samples that are often collected. The 

 time required to take a sample is longer than the other methods. The equipment is more 

 expensive (about $5,000 to construct) and more difficult to transport to the study site 

 (appendix B) . All the equipment is hand-portable but there is more of it and the equip- 

 ment takes more experience and expertise to operate. 



Regardless of these disadvantages, there may be times when this method may provide 

 the best results because it can reduce sample bias, it takes a more uniform sample, will 

 collect more sample per unit of CO2 used, the individual sample size can be varied to 

 meet analysis needs, and it offers an excellent opportunity to lift redds in their 

 natural condition. Thus, these redds could be taken to the laboratory or artificial 

 stream channel for additional study and analysis. The method can be reduced in complex- 

 ity and size to meet small sample needs. 



This method can help us better our understanding of the salmonid life cycle from the 

 egg to the emergent embryo. It is a unique experience and an education to be able to 

 dissect a redd egg pocket in its natural state. 



17 



