The most successful search so far on www.google.com was: whale hearing frequency. This website has some good info: here

This site says that reporting the frequency range for hearing in dogs and other species is not a straightforward task - the "how" of determining hearing frequency ranges must first be explained. Testing in animals differs from the method commonly used with humans of voluntarily reporting if a sound is heard. When determining the frequency range in animals, an investigator usually must first train the animal to respond to a presented sound stimulus by selecting between two actions using rewards. Often this response is to try to drink or eat from one of two dispensers when a sound is heard. The sounds are randomly presented from one side or the other, and the subject must select the right dispenser (on the same side as the stimulus) to get the reward; otherwise no food or drink is dispensed.

There's a graph of the results with 5 dogs - decibels vs frequency. It gives frequency ranges of 64-23,000 Hz for humans, 67-45,000 Hz for dogs, 1,000-123,000 Hz for beluga whale - a huge range!, but starting at a high lower frequency, compared with humans and dogs. (There were also a number of reports about whales hearing low frequencies with a google search on 'whale hearing.' You can look for those.) The table in the website also has data for a dozen or more other animals.

The graph for dogs shows them hearing sound in the range of 0 to -20 dB at their best frequency range, and needing sounds as loud as 50-70 dB to hear them at the high and low ends of their frequency ranges.