Table 2. Target strength of mesopelagic fishes at survey frequencies.
| Species/type | Taxonomy/group | Frequency (kHz) | Swimbladder | Length (cm) | Weight (g) | Avg TS (dB) | dB kg−1 | Acoustic model | Acoustic model source | Remark | L/W source |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Ceratoscopelus warmingii | Myctophidae | 38 | No | 6 | 2.0 | −73.8 | −46.8 | 49.4*log10(L)−112.2 | 56 | Ceratoscopelus maderensis | 59 |
| Diaphus chrysorhyncus | Myctophidae | 38 | No | 6 | 1.4 | −72.6 | −43.9 | 30.5*log10(L)−96.3 | 56 | Diaphus garmani | 60 |
| Diaphus garmani | Myctophidae | 38 | No | 6 | 1.4 | −71.5 | −42.9 | 54*log10(L)−113.5 | 56 | — | 60 |
| Myctophidae | 38 | No | 6 | 2.2 | −67.3 | −40.8 | 52.7*log10(L)−108.3 | 56 | Myctophum punctatum | 59 | |
| Notoscopelus japonicus | Myctophidae | — | No | 6 | 1.8 | −71.1 | −43.7 | 20*log10(L)−86.7 | 61 | Notoscopelus elongatus | 59 |
| Stenobrachius leucopsaurus | Myctophidae | 38 | No | 6 | 0.8 | −72.2 | −41.1 | 32.1*ln(log10(L))−64.1 | 62 | — | 63 |
| Symbolophorus californiensis | Myctophidae | — | No | 6 | 2.6 | −70.1 | −44.4 | 20*log10(L))−85.7 | 62 | Symbolophorus veranyi | 59 |
| Benthosema glaciale | Myctophidae | 38 | Yes | 6 | 3.0 | −58.0 | −32.8 | — | 64 | — | — |
| Ceratoscopelus warmingii | Myctophidae | 38 | Yes | 6 | 2.0 | −57.6 | −30.6 | 26.3*log10(L)−78.1 | 56 | Ceratoscopelus maderensis | 59 |
| Diaphus garmani | Myctophidae | 38 | Yes | 6 | 1.4 | −56.7 | −28.0 | 34.5*log10(L)−83.5 | 56 | — | 60 |
| Diaphus theta | Myctophidae | 70 | Yes | 5.55 | 2.6 | −55.7 | −29.8 | 20*log10(F23))−70.6 | 65 | — | 66 |
| Diaphus theta | Myctophidae | Yes | 6 | 3.3 | −54.3 | −29.5 | 11.8*log10(L)−63.5 | 61 | — | 66 | |
| Fish sb | — | 38 | Yes | <3 | −53.0 | −27.8 | — | 67 | W=3 g | — | |
| Fish sb | — | 38 | Yes | <3 | −52.0 | −26.8 | — | 67 | 67W=3 g | — | |
| Myctophid | Myctophidae | 38 | Yes | 5.8 | — | −55.0 | — | *reported modal value | 68 | — | — |
| Myctophum asperum | Myctophidae | 38 | Yes | 6 | 2.2 | −53.3 | −26.8 | 45.4*log10(L)−88.6 | 56 | Myctophum punctatum | 59 |
| Myctophid | Myctophidae | 38 | ? | NA | 3 | −56.2 | −31.0 | −31 dB kg−1 | 69 | — | — |
| Myctophid | Myctophidae | 38 | Yes | 6–10 | — | −53.0 | — | — | 70 | — | — |
| Myctophid | Myctophidae | 38 | Yes | 9 | −50 | −29.5 | *reported modal value | 68 | — | — | |
| Fish sb | 38 | Yes | — | 3–10 | −49.0 | −27.1 | — | 67 | W=6.5 g | — | |
| — | — | — | — | — | — | — | — | — | — | — | |
| Median without swimbladder | — | — | — | — | — | −71.5 | −43.7 | — | — | — | — |
| Median with swimbladder | — | — | — | — | — | −54.7 | −29.5 | — | — | — | — |
| Median all | — | — | — | — | — | −56.7 | −30.8 | — | — | — | — |
| Average all | — | — | — | — | — | −60.6 | −30.7* | — | — | — | — |
| 75% quartile all | — | — | — | — | — | −70.6 | −42.4 | — | — | — | — |
| 25% quartile all | — | — | — | — | — | −53.8 | −28.4 | — | — | — | — |
This table summarizes some recent target strength (TS) results for mesopelagic fishes. In cases where acoustic models exist, we have calculated TS at lengths close to 6 cm, and we have used published regressions for length and weight (L/W) relationships for the same or closely related species to estimate scattering from 1 kg biomass (dB kg−1).
*Average value computed on the linear domain.