Accessing files on external drive through USB
This is as close as I can get to an answer. 

It would appear the transfer rate for the bridge is 150 MBps (1.5 Gbps). This would indicate conformance to the SATA I standard. The drive has a transfer rate of 300 MBps (3 Gbps). This would indicate conformance to the SATA II standard. Even though the connectors appear to be the same, these two standards are incompatible.

Some drives have a jumper you can insert to force a SATA II drive to emulate the SATA I standard. The installation instructions for your drive do not indicate this to be true. You may want to examine the drive for possible jumpers or other instructions.

For other readers, I will mention that the SATA III standard of 600 MBps (6 Gbps) is compatible with the SATA II standard. The hardware will transfer data at the lesser of the two speeds. 

It also does not help that I can not find a web site that states the bridge is Mac compatible. All sites only mention Windows compatibility.