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Ship noise in Haro Strait 60% of time


I usually say that 20 ships per day transit Haro Strait, but this is the first time I’ve seen a sound budget estimate from Jeff Nystuen’s data. This article quotes him as saying that ships dominate the sound budget, making noise about 60% of the time his PALs were deployed. That’s pretty [...]

Killer whales call louder as vessel noise increases


This clipping from the NOAA/NWFSC Marine Mammal Program shows that southern residents are increasing the source level of their S1 calls by about 1dB for every decibel increase of the ambient noise level. Counts of vessels within 1km of the hydrophone correlate with the ambient noise levels.
While the ecological consequences of this behavioral change [...]