Full Description

"A total of 1025 source level estimates averaged 165 dBRMS relative (re:) 1 uPa (standard deviation (SD) = 1.0)."

"Call energy was greatest in the fundamental frequency (94 Hz) followed by the second (188 Hz) and third harmonics (282 Hz)."

"Based on mean RMS source level, signal propagation, background levels, and hearing sensitivity, the communication range of black drum was estimated at 33–108 m and was limited by background levels not auditory sensitivity. This estimate assumed the source and receiver were at approximately 0.5 m above the bottom. Consecutive calls of an individual fish localized over 59 min demonstrated a mean calling period of 3.6 s (SD = 0.48), mean swimming speed of 0.5 body lengths/s, and a total distance swam of 1035 m."

"The call detection algorithm successfully identified 962 sequential calls produced by an individual fish over a 59 min period."

"A total of 1025 SL estimates were calculated from calls produced by six different fish over a 59 min period and ranged from 159 to 174 dBRMS re: 1 uPa and 171 to 185 dBpeak re: 1 uPa and averaged 165 dBRMS re: 1 uPa (SD = 1.1) and 175 dBpeak re: 1 uPa (SD = 0.7). Variability in SL estimates between individuals was low (Table I). Mean call duration was 600 ms (n= 50, SD= 22). RL based on the first 15 000 sample points of a call (or 340 ms) were on average 2 dB higher than RL based on the entire call (600 ms) and variability was quite low (n = 50, SD = 0.02)."

"Recorded black drum calls were tonal and contained multiple harmonics. Throughout the course of the call, durations of positive and negative peaks increased while cycle periods decreased and an additional drop in amplitude was evident at about 300 ms (Fig. 5). The majority of energy was concentrated in the fundamental frequency (94 Hz) and the following two harmonics at 188 and 282 Hz [Figs. 4(B) and Fig. 5]. The greatest concentration of acoustic energy was most often in the 94 Hz frequency bin, although this became somewhat more variable as distance from the source to the hydrophones increased. Energy levels of higher order harmonics were much lower regardless of distance from source to receiver."

"The 962 calls produced by an individual fish over 59 min had a mean calling period of 3.6 s (SD = 0.48). This calculation included a 28 s pause in calling that occurred after 39 min, 7 s of steady calling. The total distance swam over the 59 min period was estimated at 1035 m and occurred in an area approximately 20 x 40 m."

"We documented that an individual black drum was capable of producing a 600 ms call at 94 Hz, on average, every 3.6 s ( 16 times/min) for at least 59 min."

"Mok and Gilmore (1983) originally described three different black drum call types; the staccato, loud drum, and short grunt. We observed only the loud drum call type in our recordings but when handled in captivity the staccato, a disturbance call, was produced."

"However they described the loud drum call as being composed of two distinct parts, a shorter lower amplitude “boon” sound followed by a longer higher amplitude “bound” sound."

Observation Environment Quotes

"Recordings of black drum were made from a pier in a sea-walled estuarine canal system of Cape Coral, FL (263303.00“N 8159018.50”W) (Fig. 1) during March 2005, using a four-element linear array of High Tech Inc. 96-minseries hydrophones "

"We observed only the loud drum call type in our recordings but when handled in captivity the staccato, a disturbance call, was produced."

Behaviour Description Quotes

"This behavior is reminiscent of lekking but cannot be confirmed because there are no data on the territorial distribution of other males due to the constraints of the array."

"Tellechea et al. (2010) describe shorter duration advertisement calls by black drum in Uruguay compared to recordings of black drum in Florida. "

"Mok and Gilmore (1983) originally described three different black drum call types; the staccato, loud drum, and short grunt. We observed only the loud drum call type in our recordings but when handled in captivity the staccato, a disturbance call, was produced."

Sound Name Quotes

"Canal side residents of Cape Coral, FL have long complained of loud, low frequency “booming” sounds occurring in their homes after dark during winter months. Upon conducting an acoustic survey of the canal system it was confirmed that a population of vocalizing black drum inhabited the canals and was responsible for the disturbance experienced by some members of the community."

"Recorded black drum calls were tonal and contained multiple harmonics. "

"Mok and Gilmore (1983) originally described three different black drum call types; the staccato, loud drum, and short grunt. We observed only the loud drum call type in our recordings but when handled in captivity the staccato, a disturbance call, was produced."