Description:

Tri-colored Bat calls are difficult to separate from Myotis calls. Tri-colored pulses are usually more curved once they get around 40 kHz (i.e., the tail has a curve to it). Little Brown Myotis call pulses are more of a straight line, usually a rapidly descending line, then a slightly less rapidly descending line from about 50-40 kHz. One must also consider Eastern Red Bat calls. Little Brown Myotis calls typically maintain a constant characteristic frequency, while Eastern Red Bat calls will bounce around. In areas where both species occur, one generally cannot confidently classify a call with pulses at 40 kHz as Little Brown unless there were 10 pulses that were consistent (unless highly experienced or the presence of Little Brown has been verified by other means). Little Brown calls also tend to have more of a drop off at the end of the pulse, rather than a short upward curve like Eastern Red calls. Depending on location, there may be other Myotis species with calls around 40 kHz to consider as well. Great care is appropriate because there is a lot of overlap. (B. Neece, pers. comm.)

Records:

There are 75 records in the project database.

Links:

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Seasonality: