““Ishmael” softwareIshmael” software

(by David Mellinger, NOAA (by David Mellinger, NOAA PMEL)PMEL)

•Spectrogram correlation Spectrogram correlation with synthetic callwith synthetic call

•Varied synthetic call Varied synthetic call parametersparameters

•Compared detector Compared detector performance to analyst performance to analyst (LMM)(LMM)

Analyzing the Date - Call Analyzing the Date - Call detectiondetection

Right whale and humpback Right whale and humpback callscalls

0 40 80 120

Time (s)

200

160

120

80

40

Fre

qu

en

cy (

Hz)

0 40 80 120

Time (s)

200

160

120

80

40

Sp

ect

rum

leve

l (d

B r

e c

ou

nts

2/H

z)

Right whale calls:

‘Up-call’ most common (> 80%)

Clustered into bouts

Humpback whale calls:

May appear similar to RW calls

Patterned, repeated phrases

Right whale seasonal occurrence

ResultsR

igh

t w

ha

le c

all

s/d

ay

2000-2005

J F M A M J J A S O N D

SEBS middle-shelf •Earliest yearly right whale detections in late May (2002, 2004)

•Latest in mid-December (2005)

•Highest calling rates in Aug., Sep. (2001, 2004, 2005) & Dec. (2005)

•Longest calling durations in Aug., Sep., Oct.

•Calling usually lasted 2-3 consecutive days, up to 6 d

•Intervals between calls 2-49 d (median = 7)

Daily Calling Patterns Daily Calling Patterns

•Hourly calling rates calculated for five periods of day

•Adjusted by overall calling rate for that day

•Calling rates were highest during dark period

75%

Median

Mean

25%

*

ConclusionsConclusions

• Right whale occurrence varied by Right whale occurrence varied by season and between yearsseason and between years

• Calls were detected for only a few Calls were detected for only a few days at a timedays at a time

• Calling rates were highest at nightCalling rates were highest at night• Right whales were in the Southeast Right whales were in the Southeast Bering Sea as early as May and as Bering Sea as early as May and as late as Decemberlate as December