Table 2.
Summary of fin whale song trends studies. For intra-annual IPI shifts, since trends are not linear, we report the difference between low IPI season and high IPI season (summer vs winter). Note that the inter-annual IPI shift of Morano et al.11 is reported between two consecutive years only, and the frequency shifts of Leroy et al.28 are for the 99 Hz pulse rather than the 20 Hz pulse.
| Study | Location | Inter-annual | Intra-annual | ||
|---|---|---|---|---|---|
| Frequency | IPI | Frequency | IPI | ||
| Weirathmueller et al.9 | N.E. Pacific | − 0.17 Hz/year | 0.5–0.9 s/year | – | – |
| Oleson et al.21 | N Pacific | – | – | – | + 7.5 s |
| Leroy et al.28 | Indian | − 0.21 Hz/year | - | − 0.1 Hz/mth | - |
| Helble et al.10 | N. Pacific | – | 0.6–1.3 s/year | – | – |
| Morano et al.11 | N.W. Atlantic | – | 0.5 s/year | – | + 5.5 s |
| Watkins et al.5 | N.W. Atlantic | – | – | – | + 6 s |
| Furumaki et al.46 | Chukchi Sea | – | 0.5 s/year | – | + 1 s |
| Širović et al.24 | Gulf of California | – | 1 s/year | – | + 8 s |
| Wood and Širović20 | W. Antarctic | − 0.2 Hz/year | 0.1 s/year | – | – |
| Ours | Mediterranean | – | 0.1 s/year | –0.1 Hz/month | – |